LIBRARY STATE PLANT BOARD June 1947 E-728 TOUTED STATES DEPARTMENT OF AGRICULTURE AGRICULTURAL RESEARCH ADMINISTRATION BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE A THIRD DIGEST OF THE LITERATURE ON DDT (January through June 1945) By R. C. Roark and N. E. Mclndoo Division of Insecticide Investigations >EP 2 9 1947 -2- CONTENTS Page Definitions ••••• 5 Chemistry •••••• ••••••••••••••••*••• 5 Effect of solvents for DOT on its toxicity to insects ••••••• 9 DDT formulations 10 Pharmacology •••••••••••••• ••••• 13 Effect of DDT on plants 17 Effect of DDT on fungi • 20 DOT spray residues ana their removal 20 Effect of DOT on wildlife , 23 Production 26 Allocation 26 Cost 29 Patents and trade-marks 29 DDT in aerosols 30 Use of DDT by pest control operators 31 Reviews and popular articles • 31 Insecticidal value • 52 Nematoda: Anguillulidae • 33 Thysanura: Lepismatidae • 33 Orthoptera: Acrididae 34 Blattidae 35 Gryllidae 37 Mantidae 38 Dermaptera: Forficulidae 38 Is opt era: Armadillididae • 38 Rhinotermitidae • •••• • 38 Mallophaga: Menoponidae • • • •••• 38 Trichodectidae • • • 39 Thysanoptera: Thripidae ••• •• 39 Hemiptera (Homoptera) : Aleyrodidae • • 44 Aphiidae • ••••.......... • 44 Cercopidae ..••• 51 Cicadellidae 52 Cocoidae .....•••• • • 58 Psyllidae 62 Hemiptera (Heteroptera) : Anthocoridae 62 Cimicidae • • 63 Coreidae 64 -3- CONTENTS (continued) Page Lygaeidae • ••• •• 65 Hiridae 66 Nabidae 72 Pentatomidae • • • 72 Triatonidae •••••••• ••••• 75 Anoplura Haematopinidae ••••••••••••. •••••• • 75 Pediculidae 76 Coleoptera: Anobiidae •••••••••••••••••.. • » • 77 Bostrichidae 77 Bruchidae •• •••••••••••• • 77 Byturidee 78 Cerambycidae ••• ••• 79 Chrysorcelidae • • 79 Coccinellidae 87 Cucujidae •• 88 Curculionidae • •••• •••••• • 88 Derrsestidae 92 Blateridae • • 93 Eumolpidae 94 Meloidae ...*•••..... • •• 94 Ostomidae •• 94 Scarabaeidae •• • 95 Scolytidae 98 Tenebrionidae ...*••. ••• •• •••••••••• 98 Nsuroptera: Chrysopidae 100 Lepidoptera Aegeriidae • ••••••••••••• 100 Arotiidae 101 Citheroniidae 101 Coleophoridae • • ••••••••••••••••••••••• 101 Crambidae 101 Gelechiidae 102 Geometridae • • 103 Glyphipt erygidae •••••••• ••••• 103 Hyponomeutidae ••••••• •••...•••••••.•...•......•» 103 Lasiocampidae •• ••••••••••••• 104 Lymantriidae •••••••••• ••••• 104 Notodontidae •••••• • ••••• 105 Olethreutidae • • 105 Phalaenidae •••••• •••• 110 Fhaloniidae • 115 Phycitidae 115 CONTENTS (continued) Page Pieridae 117 Plutellidae ••••• 118 Psychidae us Pyralidldae 118 Pyraustidae , 119 Sphingidae 121 Tineidae , 122 Tortricidae 122 Hymen opt era: Apidae 124 Formicidae 125 Sphecidae 127 Diprionidae o 127 TricnOfTrammatidas .......••••.••• • • •• 128 Vespidae • 128 Dipt era: Anthomyiidae 128 Calliphoridae 129 Chironomidae • .....•• 129 Culicidae 130 Itonididae •••• • 138 Muscidae ...••••••• •••••••• .••.....•• 138 Oestridae *.r .•••••••••••••• •••••• 145 Psilidae 145 Sep3idae ......•.»..•••.......... ••••• 146 Simuliidae • 146 Syrphidae • • • • • 146 Tabanidae 147 Tachinidae •••••••• • • 147 Trypetidae 148 Siphonaptera: Pulicidae • 149 Scorpionida • 150 Aran ei da 150 ^.carina: Eriophyidae • 151 Ixodidae 151 Ssrcoptidae 151 Tetranychidae 152 Trombiculidae 155 -5- This digest abstracts the articles included in the third list of publications on DDT (E-674) • The literature referred to in the first and second lists of publications on DDT has been reviewed in the first (E-631) and second (E-687) digests. Nearly 1,000 publications deal- ing with DDT which had appeared up to July 1, 1945, are covered in these three digests. DEFINITIONS M The term , DDT I refers to the tecnnical grade of 2,2-bis(parachloro- phenyl) 1,1,1-trichloroethane, which contains as impurities considerable amounts of isomers and much smaller amounts of other by-products formed in its manufacture. So far as we are now aware, the normal impurities in DDT are active ingredients within the meaning of the Insecticide Act of 1910. Therefore, its label is not required to bear an ingredient statement." — Reed (300 ). It is recommended that in the future the term ^p^'-DDD' 1 be used exclusively for reference to H 2,2-bis-(p-chlorophenyl)-l,l-diohloro- ethane. — Gunther (195). CHEMISTRY Synthesis The preparation of DDT in the laboratory is described in such a way that it can be performed as a regular experiment in the beginning course in organic cnemistry. 45 grams (0.2 mole) of monochlorobenzene and 34 grams (slightly over 0.1 mole) of chloral hydrate are added to 350 grams of 95-percent sulfuric acid and 50 grams of 20-percent oleum; the mix- ture is stirred for 90 minutes, during which time the temperature rises to 45°C. The reaction mixture is poured into 2 liters of ice water and the solid product washed on a funnel under suction with cold water. The crude product is then melted in 500 ml. of boiling water, allowed to solidify by cooling, and the wash water removed by decantation. This process is repeated two additional times, and sodium bicarbonate is add- ed to the last wash water to remove the last traces of acid. The product is then collected on a suction filter and dried. The yield of crude ma- terial (m.p. about 90°C») is about 70 percent of theoretical. It can be purified by re crystallization from ethyl or propyl alcohol.— Darling (126 ) . The laboratory preparation of DDT according to Zeidler's procedure, using chloral hydrate instead of chloral, is described. The mixture is heated under a reflux condenser to 122°C. for Z\ to 3 hours, or is stirred with heating (not to exceed 105°) for 8 to 10 hours. — Bailes (80). Physical properties A procedure for determining the setting point of TDT is described. -6- A mixture has the lowest containing 25 percent of jp^'-DDT and 75 percent of _o,p ! -l west setting point, namely 39.1°C. The setting point for DDT point for a mixture containing 70 percent of Pjj^-DDT is 86. 5-87. 2°, and for one containing 80 percent of pjp'-DDT 95.2°. A setting-point curve for mixtures of these two isomers is presented from which it is possible to ascertain the composition of any mixture from its setting point. The content of p.p'-DDT in technicel DDT as indicated by the setting point checks well with that obtained by recrystallization from alcohol. The solubility of pure _p,p*-DDT in alcohol at 30° is 1.6 gram per 100 ml. — Fleck and Preston ( 154 ) . This procedure was adopted by the U. S. War and Navy Departments (357 ) • DDT crystallizes in the orthorhombic system and has a density of approximately 1. The powder X-ray diffraction pattern was determined. —Clark and Cagle (113 ) • Composition of technical DDT Technical DDT, of setting point 88°C. as obtained in the Brothman continuous process, is* of the following approximate composition: jDjja'-Isomer (DDT) o,p*-l8omer •••••••••• o, o'-Isooer •••• • **0ily by-product" (unidentified) .... Peroent 70 18 6 Percent Unidentified solids... 2 Volatile material .... 1 Ash 1 A material of higher setting point would contain a greater percentage of actual DDT. — tiunther (195 )* Attention is directed to the various isomers of DDT which may be present in variable proportions in different batches of material, and to the erroneous hypothesis that when DDT is dissolved in petroleum oil its surface tension is reduced. --Calif • Agr. Expt. Sta. ( 101 ) . Reactions of DDT DTTT prepared according to Zeidler*s procedure was dehydrochlorir.nted by boiling in alcoholic potassium hydroxide; the resulting ethylene prod- uct (m.p. 86-87 c 0.)was oxidized with chromic acid in acetic acid to p,p'- dichlorobenzophenone, which establishes the position of the chlorines as p,p' in DDT. Several attempts to oxidize p,p f «LrT with chromic acid in acetic acid to p,p , -dichlorobenzophenone gave no identifiable products. l,l-Di(j)-chlorophenyl)-l,2,2,2-tetrachloroethane (m.p. 91-92°) is readily made by chlorination of the trich lor o ethane compound or the dichloro- othylene derivative.- Urummitt et aJL. (190). -7- Di-(p-chlorophenyl)acetio acid (m.p. 163-164 c C)was prepared by heating l,l-di(p-chlorophenyl)2,2-dichloroethylene with alcoholic potassium hydroxide in a sealed Carius tube at 150-160° for 20 hours, --Grummitt et al. (19 1). DDT is very sensitive to alkaline materials. It "dehydrohalogenates* upon heating slightly above its melting point. The technical grade, •which contains appreciable quantities of the heat-sensitive o,j3*-isomer, may begin to oleave hydrogen chloride at 50°C. At 80° a 90-"percent lose of insecticidal efficacy occurs within 24 hours. The heat-induced de- composition of DDT appears to be auto catalytic, the liberated hydrogen chloride initiating further decomposition. In the absence of excessive temperatures, the primary decomposition product, DDD ^meaning the ethylene derivative, also known as TDE - RCR] is more stable than the parent compound. Contrary to the early reports, under summer field con- ditions in southern California, where leaf temperatures may exceed 125°F. and fruit temperatures 135°, DDT was found to lose its residual effect very quickly. Usually 2 weeks was more than sufficient to eliminate toxic effects. Experiments performed under winter conditions, however, indicated little, if any, loss of toxicity over several months. These results, and similar reports from other investigators, suggest that ultra- violet energy, between 2875 and 3100 A. U., may be another catalyst for the dehydrohalogenation of DDT, although Garman and Towns end report that sun-lamp irradiation does not destroy the effectiveness of DDT as a dust. Light may break DDT down to j3,p , -dichlorobenzophenone.--Gunther (195 ) . Gesarol AK-20 spray proved to be entirely compatible with wettable* sulfur. — Conklin (116 ). DDT is a rather stable compound. Long periods of exposure to the air have caused no appreciable ohange. Irradiation of the solid materi- al, spread in a thin layer, for 35 hours with a 100-watt mercury-vapor lamp, lowered its melting point by only 2°C. Similarly, an alcoholic solution of pure DDT showed no change after exposure to sunlight for over a year. DDT in alcoholic solution is readily decomposed by alka- lies to 2 f 2-bis(p-chlorophenyl)l,l-dichloroethylene, m.p. 88-89° • DDT was decomposed wnen heated with an equal weight of the following materi- als for 1 hour at 115-120*: Kaolin, fuller's earth, iron rust, ferric chloride, nicotine, and certain samples of talc and pyrophyllite. DDT was not decomposed when heated with calcium oxide, hydrated lime, or commercial lime-sulfur; and was only slightly decomposed (4 to 7 percent) when heated with bordeaux mixture or sulfur. Commercial grades of sodi- um fluoride, sodium fluosilicate, cryolite, paris green, calcium arse- nate, and lead arsenate showed no catalytic activity in decomposing DDT. Likewise, pure rotenone and pyrethrum were found to be inactive. Dolo— mitic limestone was the only fertilizer tested which showed catalytic ectivity. Heating the mixture for 1 hour produced 0.89 mole of hydro- chloric acid. The catalytic action persisted after the limestone had -8- been slurried with water and then dried at 110°C. This treatment would destroy the oatalytic action if it were due to small traces of anhy- drous ferric, aluminum, or chromic chloride. Most solvents inhibit the catalytic decomposition of DDT by anhydrous ferric chloride, exceptions being nitrobenzene and chloroben2ene. With o-dichlorobenzene the cata- lytic action occurred even at room tejnperature«--Fleck and Ealler (163 ) ♦ Analytical methods A procedure for recovering organic chloride (DDT) spray deposits from apples consists in extracting 10 to 25 fruits with acetone or ben- zene and determining chlorine in the solution.-— Fahey (148 ) . DDT spray deposits on fruit or other material are removed with ben- zene, inorganic chlorides are removed from this solution by extraction with several portions of water, the benzene is removed by evaporation, and the DDT is decomposed by refluxing with 1 N alcoholic potassium hy- droxide for 30 minutes. The resulting potassium chloride is determined by titration. Recovery of known amounts of DDT by this method was 99.5 to 101 ^percent.— Gunther ( 194 ) • Instructions are given for the determination of labile chlorine, total chlorine, and DDT by the Schechter and Haller coiorimetric pro- cedure. The ratio of labile chlorine to total chlorine on seven samples of DDT-sprayed apples from experimental plots in the western, central, and eastern apple areas ranged from 0.192 to 0.216, which closely approximates the theoretical 0.200* Recovery experiments wherein DDT was added in amounts equivalent to 1-15 p.p.m. to benzene extracts of unsprayed apples indicate that the over-all error of ohlorine methods (exclusive of the errors of sampling and sample preparation) is approxi- mately ^ 0.1 p.p.m. The errors at these levels affected the ratio of labile to total chlorine to the extent of about - 0.01. If the devia- tion from theory is greater than this, the sample should be subjected to further investigation.— U. S. Food and Drug Administration (353 ) * A coiorimetric method for the microdetermination of DDT is presen- ted. The test is based on the discovery that, when DDT is heated in an anhydrous pyridine solution containing xanthydrol and solid potassium hydroxide, a red color develops, which under proper conditions is pro- portional to the amount of DDT present. The reaction is sensitive to as little as 10 micrograms of DDT. It will detect small differences in concentration within the range of 10 to 200 micrograms. — Stiff and Castillo (338 ). Solvents for DDT The addition of 15 percent of a special methylated naphthalene [Velsicol] to kerosene makes a solvent that holds DTYT in solution at -9- temperatures as low as -20°F. The War Departments specifications for DDT spray have been revised to require the inclusion of this substance. —Anon* ( 35 ) • The solubilities of pure DDT, m.p. 107-108*^ in nine organic sol- vents (acetone, benzene, carbon tetrachloride, chloroform, dioxane, ether, ethanol (95%), petroleum ether (30-60°), and pyridine) at 0°, 7,2°, 24 , 45 , and 48°C. were determined. At all temperatures except 0°C. the solubility is greatest in pyridine, and at that temperature it is greatest in acetone. Benzene is the most efficient stripping solvent for pure DDT at room temperature.— Gu nth er ( 193) . Methylene ohloride is an excellent solvent for DDT and can be used as an auxiliary solvent to make it more soluble in Freon-12 (dichlorodi- f lu or om ethane) • Dimethyl ether and methyl chloride are good solvents for DDT .—Goodhue et al. (181 ). The following solvents for DDT were used in tests upon houseflies and cockroaches: Deobase, acetone-Deobase, toluene, Deobase^mineral oil, and cyclohexanone.— Goddin and Swingle (179 ) . At room temperature the solubility of DDT in some of the common solvents is as follows: Solvent Grams per 100 ml . Solvent Grams per 100 ml . Cyclohexanone ••••• 100 to 120 Kerosene, crude .. 5 to 8 Xylene •••• 56 Kerosene, purified 2 to 4 Ether 29 Ethyl alcohol.... 1.5 Diesel oil No. 2... 10 Calif. Agr. Expt. Sta. (101 ). EFFECT OF SOLVENTS FOR DDT ON ITS TOXICITY TO INSECTS Laboratory tests conducted at Beltsville during the winter of 1944- 1945 indicate that the nature of the solvents used with TOT has an impor- tant bearing on its toxicity. Some solvents, such as kerosene, evaporate quickly (a matter of minutes), leaving needlelike crystals that are very durable, the toxic effects lasting from 3 to 6 months under outdoor weathering. These tiny crystals may penetrate the footpads of "the insects and possibly enter the pores in the 6clerites of the body. Velsicol AR-50 (a mixture of mono- and di-methylnaphthalene) produces similar crystals, but these require a day or more to form. Heavy solvents, such as Diesel oil, remain tacky for days and leave a deposit that is not so persistent as that resulting from kerosene. On the other hand, these tacky or viscous films kill several times as quickly.— Craighead and Brown (125) • -10- DDT FORMULATIONS Chemically pure DDT melts at 108.5°-109°C. Two grades of commercial product are available — technical DDT, specified to have a setting point not lower than 88° j and DDT, purified, specified to have a melting point of at least 103°. The former has found use in louse powders, mosquito larvicides, and in general agricultural experimentetion; the latter is intended for use in aerosol bombs. DDT has been used in water suspen- sions, solutions, emulsions, dusts, and aerosols. Water suspensions are divided into three classes (l) those resulting from the mixing of finely- ground DDT (ground either dry or wet) with water, (2) those resulting from the dilution with water of a solution of DDT in a water-mis cible orgpnic solvent, and (3) those obtained by mixing diluents impregnated or coated with DDT with water. The preparation of these formulations is discussed.— Chisholm (112 ) . G-esarol AKZ-40 Spray is a powder containing 40 percent of DDT which is easily wettable and stable in water suspension. It has been design- ed particularly for use with Gesafloc spreader (a liquid soap spreader preparation) in the control of codling moth.— Geigy Co. (167 ) . Gesarol AK-40 Spray is a powder containing 40 percent of DDT. It is easily wettable and stable in water suspension.— Geigy Co. (168 ) . Gesarol A-20 Spray is a finely ground powder containing 20 percent of DDT. It is easily wettable and stable in water suspension, and con- tains an amount of wetting agent and sticker necessary for the recommend- ed uses. Geserol A-20 spray is designed for use on such hard to wet crops as onions, corn, and certain ornamentals and shade trees where good wetting or penetration of leaf -axils is required.— Geigy Co. (173 ) . The composition of some Geigy products tested in California is as follows: GNB-A is "commercial pure" DDT A3 is a 3 percent DDT dust A-20 is 20 percent DDT witn wetting agent AK-20 is 20 percent DDT without wetting agent SH-5 is 5 percent DDT in emulsive oil base SH-20 is 20 percent DDT in emulsive oil base SHN-20 is 20 percent DDT in nonemulsive oil base .—Calif. Agr. Expt. Sta. (101). Neocid Spray Deodorized contains 5 peroesit by weight of DDT in a deodorized kerosene base. It should be used undiluted as a residual-type spray in the control of flies, mosquitoes, bedbugs, fleas, silverfish, clothes moths, carpet beetles, ticks infesting buildings, cockroaches, poultry mites, and fowl ticks ("bluebugs"). — Geigy Co. ( 172) . -11- Neocid Barn Spray is a finely ground wettable powder containing 20 percent of DDT and a suitable quantity of a spreading and sticking agent. It nay be used either as a residual-type spray against flies and adult mosquitoes or as a dip against cattle and goat lice and sheep ticks. -- Geigy Co. (171 ). Neocid A-10 Powder is a finely ground dusting powder containing 10 percent of DDT. It is designed for use without further dilution in the control of roaches, fleas, carpet beetles, bedbugs and other insects affecting man, poultry, and livestock.— Geigy Co. (170 ) . Gesarol Dust Concentrate contains 40 percent of DDT and is design- ed for dilution in ordinary dust-mixing equipment without additional grinding. Recommended diluents in the order of preference are (l) non- fibrous talcs of good dusting quality, (2) pyrophyllites of dusting grade, and (3) dusting clays, diatomaceous earths, oalcium carbonate or chalk, gypsum, and fibrous talcs. Do not use hydrated lime, bentonites, or fuller's earth as diluents in the preparation of Gesarol dusts, as they seriously reduce the efficiency of the product. Certain organic fillers, such as walnut-shell flour, have a similar, though less serious, effect and are therefore not recommended .--Geigy Co. (169) . Unmodified 13DT is not in suitable form for the consumer. The Array and Navy have about six products made to their specifications. DDT will be used in the form of dusts, solutions, aqueous suspensions, emulsions, and aerosols. For the conventional household fly spray, the recommenda- tion is the addition of 0.2 percent of DDT with whatever reduction in present aotive ingredient can be tolerated to provide knock-down, sinoe even this small quantity of DDT will give "kill.** IDT formulations, which may be of many compositions and strengths, must be tried and proved to establish proper claims.-- Jeneman (226 ) . Among the DDT insecticides authorized for supply by the U. S. War Department (25, 358 ) June 1945 were the following: Insecticide, aerosol, 1-pound dispenser (3 percent DDT, 2 percent pyrethrum extract containing 20 percent pyrethrins, 5 percent cyclohexanone, 5 percent hydrocarbon oil and 85 percent Freon-12) • The aerosol bombs are an olive-drab color affording easy differentiation from the black dispensers previously issued which contained pyrethrum, sesame oil, and Freon-12. Insecticide, DDT emulsion concentrate (25 percent DDT, 10 percent emulsifier, 65 percent xylene) . Stock mixture for making a 2-percent DDT emulsion to be used primarily in louseproofing clothing and to a limited extent for larvicidinp purposes. Insecticide, spray D7YT, residual effect (5 percent DDT, 15 percent solvent, and 80 percent kerosene) . For use in killing flies, mosquitoes, roaches, bedbugs, ants, and other insects that -12- rest or crawl on treated surfaces. Should be applied only by trainad personnel. May also be used to treat contents of pit latrines and to spray decomposing bodies and other organic material such as destroyed ration dumps* Insecticide, liquid, finished spray (l percent DDT, 2^- percent Thanite, in deodorized kerosene). For troop use spray di- rectly on the insects or into the air in which the insects are flying (mess halls, barracks, etc.). Has no residual effect. Insecticide, powder louse, 2-ounce ca n (10 percent DDT in pyrophyl- lite) * Issued to individuals for use in eradicating and pre- venting louse infestation by applying to inner surface of underclothing • Insecticide, powder, louse (10 percent DDT in pyrophyllite) . For use primarily in mass deleasing with power or hand dusters. May be used to control bedbugs, roaches, ants, and to treat habitats of fleas and mites • Insecticide, spray, de lousing (6 percent DDT, 68 percent benzyl, benzoate, 12 percent benzocaine, 14 percent Tween-80) • Must be diluted 1 to 5 with water just prior to use. Kills both adults and eggs of body, headland crab lice. Also an effec- tive scabicide. Larvicide, DDT, powder, dissolving (100 percent DOT, commercial grade) • For dissolving in oil or other approved solvents to form solutions up to 5 percent DDT, for use as larvioides, residual sprays, and airplane sprays* Larvicide, DDT, powder, dusting (10 percent DDT in talo) • For use as a mosquito larvicide after diluting to make a 2 percent DDT mixture. Also for use as fly larvicide and roach powder without dilution. May be applied to habitats of fleas and mites. The Crop Protection Institute during 1944 studied the relation of DDT to solvents and liquid carriers, and to various dry diluents. A large number of representative liquid carriers and more than 30 inert diluents for dust have been studied. From these investigations several formulations have been developed which are safe on plants and which permit DDT to perform to advantage.— 0' Kane ( 277 ) . DDT is not .in itself a complete insecticide, but is a toxicant which requires very careful compounding with other compatible substances to aot as diluents or carriers. — Anon. (9) • -13- Speolfications The U. S. War and Navy Departments (356 , 357 ) have issued joint Army-Navy specifications covering DDT, both technical and aerosol grades. PHARMACOLOGY DDT was administered "by mouth, subcutaneous injection, inhalation, and cutaneous application to mice, rats, guinea pigs, and rabbits. It was concluded that DDT insecticides should be considered as practically harmless to mammals, including man. — Domenjoz (135) • The use of an aerosol containing 1 to 5 percent of DDT, 10 percent of cyclohexanone,and 89 to 85 percent of Freon should offer no serious health hazards when used under conditions such as are required for its use as an insecticide* The use of DDT in concentrations up to 10 percent in inert powders for dusting clothes, as in the extermination of lice, appears to offer no serious hazards because of the relative insolubility of DDT and the large particle size of the dust* Therefore, it does not reach the alveolar spaces* A 1 peroent DDT-Deobase mixture was found to be nontoxic to rabbits exposed for 48 minutes daily over a period of 4 weeks* Its use as a fly spray, which involves only temporary and com- paratively moderate exposure to much lower concentrations, should be safe* However, owing to the fat-solvent properties of most petroleum distillates, irritation of the skin may follow heavy exposure. — Neal ( 273 ) ♦ Two aerosol mixtures, containing 3 and 2*5 percent of DDT, were test- ed on guinea pigs, rats, mice, monkeys, and dogs. Monkeys exposed for 45 minutes daily to a single, initial concentration of 33*3 mg. of DDT per liter for 22 weeks and longer showed neither definite nervous symptoms characteristic of DDT nor signs of an injurious effect on the liver. For entomological purposes the initial concentrator of DDT in air, when used as an aerosol, is about 100 to 200 mg. per 1,000 cubic feet, correspond- ing to about 0.004 to 0*007 mg. per liter. In the inhalation experiments reported above, the initial concentration ranged from 19 to 33 mg. per liter, or 3,000 to 4,500 times the desired entomological concentration* It is evident, therefore, that the desired entomological concentration offers no health hazard. The contamination of the skin from such residues as are produced by -the desired lnsecticidal concentration of DDT in air is so little that it will not injure humans. However, careless handling of DDT residues, as in the filling of the aerosol bombs, may result in such severe contamination of the skin, especially with repeated exposure, that toxic effeots might occur in humans*— Neal et al. (272 ) * Aerosol No. 305, containing 2 percent of pyrethrum extract (20 per- cent pyrethrins), 3 percent of DDT (aerosol grade), 12 peroent of APS-202 and 83 percent of Freon-12, was tested on mice, rats, and dogs* The -14- animals were placed in a hermetically sealed glass chamber of 409.7 liters capacity, a 1-pound aerosol cylinder was discharged into the closed chamber, and the animals were exposed to the resulting mist for 46 minutes daily, 6 days a week, for 1 montii. Under these con- ditions APS-202 is not a primary skin irritant and, unlike Vel6icol KH70, it is not photosensitive when applied to the skin. Aerosol No, 305 is no more toxic than No, 2730 (contains 3 percent of DDT), studied previously, and its use as an insecticide should not involve any hazards.— von Oettingen et al, (363), In solid form DDT applied topically to the skin is nonirritating, nonsensitizing, and not appreciably absorbed. In solution, either in oil or in organio solvent, it readily penetrates the skia and is mildly irri- tating and sensitizing. In single and multiple dose administration (acute and subacute) there are wide individual as well as wide speoies variations. In prolonged feeding experiments (chronic toxicity) rats have been fed diets containing 100, 200, 400, 800 ppn. of DDT for about 18 months. Guinea pigs, dogs, and monkeys have been studied for shorter periods* The pharmacological manifestations of effect from DDT are principally loss of appetite, mild to severe tremors of central nervous system origin, convulsions, and death. Tremors can be prevented or abolished by general anesthetics and narcotics* Histopathologic examination of tissues of animals which have received DDT shows damage which is neither striking nor characteristic for all speoies,— Calvery (103), DDT is cumulative in effect. "Whether this central nervous system effect is reversible we do not know. The tremors can be completely abolished by sedatives, and in my opinion if this is done that animal is recovered. But if it has gone on long enough to affect the internal or- gans, that may not be reversible. Except sedatives, there is no specific treatment for DDT poisoning ."—Calvery (104), Typical signs of 17DT poisoning «bserved on mammals under laboratory control were lessened appetite with corresponding weight loss, nervous- ness, tremors, and in the final stage convulsions. Tho liver and thyroid may be affected and, after repeated application to the skin, a slight dermatitis may occur. The exposure to large doses of undiluted DOT in powdered form produced no synptoms of poisoning in animals with either intact or abraded skin. However, solutions of DDT in a nonirritant sol- vent such as dimethyl phthalate caused severe poisoning. No irritation was noted from powdered DDT on the hands of operators who had almost daily contact with it during the past year, A number of commercial pre- parations containing up to 6 percent of DDT have proved safe for limited use. The inunction of doses as low as 0*5 ml, of a 30 peroent solution of BDT per kg, per day (150 mg, per kg. per day of DDT) to rabbits, rats, and guinea pigs may cause death in some cases after 30 days. Affected -15- animals became easy prey to secondary infections. The effects of DOT in experimental animals are cumulative! small single doses given re- peatedly lead to chronic poisoning* In a group of 10 rats eaoh weigh- ing about 80 grams, DDT fed at a level of 0*1 percent in the diet was uniformly fatal in from 18 to 80 days*. Generalized tremors were present throughout* At a level of 0*05 percent of DDT the animals survived 3 months, though there was some impairment of growth* In the study on rabbits a mild degree of anemia was evidenced by a reduction of the hemoglobin level* White blood cell counts however, failed to indicate significam; deviations from the normal* The safe level in human foods cannot be over 10 p*p*m* "I, myself, would not risk more than 70 milligrams, or 1 mg* per kilogram •"— Calvery (105 ) • Daily doses of oily solutions containing 10 percent of DDT were administered orally to dogs in the ratio of 100 mg* of the drug per kilogram of body weight until symptoms of intoxication appeared* In some cases slight symptoms were apparent after a few days, but the animals recovered promptly and spontaneously* It was only after new administrations of DDT that intense symptoms were observable* Spon- taneous recovery occurred 12 to 24 hours after treatment* From then on the susceptibility of the animals to the drug inoreased greatly* To verify the effect of calcium on the development of the symptoms of poisoning, these animals were given doses of 150 to 200 mg* of DDT per kilogram of body weight* Calcium gluconate (10 percent solution) was injected intravenously to investigate its curative and preventive effects* "The satisfactory results obtained by the use of calcium gluconate in prevention and treatment of dogs experimentally intoxicated by DDT suggest that the apparent neurologic symptoms observed are consequent to hypocalcemia, and not due to direct action of the DDT upon the central nervous system*" All but one of the six dogs used in these ex- periments was in apparently good physical condition a month after the experiments were ended*— Vaz et al* (361 ) * Beginning January 10, 1944, rats were kept on a diet containing 1 part of DDT in 10,000 parts of foodstuff. On March 11, just 2 months later, they began to have convulsions* Two days later half the rats were restored to normal food with near disappearance of convulsions* However, both the withdrawn rats and those remaining on the DDT diet died within the next 2 days* In May 1944, the Bureau of Entomology and Plant Quarantine fenced 3/4 acre of grassland containing grasshopper egg masses about 60 miles from San Diego, Calif* When the hoppers were emerging, the area was fairly effectively du3ted at the rate of 40 pounds per acre with a 10-percent DDT dust* After 48 hours the California State Bureau of Chemistry was permitted to put 3 ewe sheep in the field* After 72 hours the sheep showed extreme neurologic symptoms, reminding one of dogs suffering from rabies* Nervous disorder in the sheep was characterized by tremors and especially by motion in the hind legs simi- lar to stringhalt in horses* Iheir necks seemed to be affected, as they -16- would keep their noses to the ground but did not grate. The animals eventually recovered, probably due to removal of the DDT dust from the vegetation by wind, the tramping of the animals, and a slight rain. A month later the test was repeated. The animals behaved in the same manner as with the first treatment but again all recovered. One of the ewes was taken to the University of Southern California where the feed- ing experiment was continued. Beginning July 10, a dosage of 2 grams of DDT daily was administered orally by capsule for 11 days. No symptoms were notioeable and the dose was inoreased to 4 grams per day and con- tinued for 40 days* On August 30 still no symptoms were noticeable and the dose was further increased to 8 grams daily for 14 days and thai 16 grams daily; death ensued 17 days later. After the dosage was increased to 16 grams a day pronounced nervous symptoms in the form of tremors of the hind quarters and pawing with the forelegs were soon observable. These symptoms became more pronounced until the animal was unable to rise from the ground and stand on all four legs or manage itself. Upon au- topsy the kidneys and liver showed moderate degeneration.— Cox (121 ) • A 5-percent solution of DDT in olive oil was given by stomach tube to rabbits. Crystalline DDT was isolated from the urine and feces.— Stohlman (339 ) • The presence of TOT in rabbit urine could not be verified by X-ray diffraction analyses but the metabolite di(p-chlorophenyi) acetic acid was isolated.— White and Sweeney (372) . Organic chlorine can be demonstrated in the urine of rabbits, cats, and dogs receiving DDT long in advanoe of any recognizable symptoms of poisoning. Experiments on the circulatory and respiratory responses to some typical drugs and to nerve stimulation in advanced DDT poisoning in cats indicate little deviation from the normal except for a lowered irritability of the peripheral vagi. Studies on the aetion of a series of hypnotics and related compounds in acute DDT poisoning in rats indi- cate good antidotal effects from urethane and to a lesser degree from dilantin. — Smith and Stohlman (326 ) • The ethoxy analog of DDT appeared less toxic than DDT when fed to white rats.— Prill et al. (297 ) • DDT in a 1-percent solution in liquid paraffin or olive oil showed very little effeot against notoedric mange on rats. In a 2-percent so- lution, it led to the death of some of the experimental rats after the development of marked hyperesthesia and frequent clonic muscular spasms. — Taylor (343 ) • In a later report Taylor (344 ) stated: "One of the rats that had been dressed with 1 percent DDT in liquid paraffin developed symptoms of intoxioation within 24 hours and died. Two other rats were subsequently dressed with a 10-peroent -17- solution in the same way and developed the same symptoms, which took the form of a hyperesthesia increasing in intensity until any sudden noise or movement was sufficient to induoe general- ised clonic spasms, which became continuous in the later stages and led to the death of the rats*** The author ate two or three "bunches of sound grapes and peeled peaches that had been sprayed with IDT, with no bad effects in either case*— Brcoley (96) . EFFECT OF DDT ON PLANTS Tomatoes, potatoes, cabbage, turnips* onions, beans, peas, and to- baoco are tolerant to low strengths and reasonable dosages of DDT dusts, but some injury to squash or other cucurbits may be expected*-- ^Riite (573) » A 10-percent solution of DDT in cyclohexanone and light petroleum oil was sprayed in two areas at the rates of 6 and 4 pounds per acre. Neither 4osage caused any apparent injury on coniferous trees, but the foliage of deciduous trees showed injury which varied according to the speoies, as noted: Species E3M^£2^JS^EI. Speckled alder, Alnus incana Medium marginal, some spotting Aspen, jPopulus tremuloides Medium spotting Gray birch, Be tula populifolia Slight spotting White birch, Betula papyrifera do® Yellow birch, Betula lutea do Black cherry, 'Prun uT ^sTrotina Light marginal Chokecherry, Prunus virginiang Severe marginal Pin cherry, P runus peimsyl vaaloa Light to medium marginal Hazel, Corylus spo Slight spotting Mountain maple, Acer spicatum Medium marginal Red maple, Acer rubrum ~ Medium marginal and spotting Nannyberry, 'vffiurrann 'lent a go Light to medium marginal Serviceberry, Amelanc hi er canadensis do» Willow, Salix sp* d©« Bracken, raspberry, blueberry, strawberry, and wild honeysuckle suffered light to medium foliage injury.— Ross (306 ) #> Most of the trees and plants on which DDT was used have not shown evidence of injury* On some apple trees, however, there was some yellow- ing and dropping of foliage, but an increase in mite abundance was large- ly, if not wholly, responsible* In experiments with soil treatments for Japanese beetle grubs, 25 pounds of DDT per acre definitely retarded the growth of bush beans, lima beans, soybeans, hollyhock, onions, spinach, and tomatoes* Some of the bean leaves became yellow, and tomato plants -18- were somewhat distorted. Higher strengths caused some growth retarda- tion in beets, carrots, muskmelons, and potatoes. Tests are under way in which excessive quantities of DDT were applied to the soil under apple and peach trees, to simulate the accumulation that might occur over a period of years if DDT should oome into general use. Thus far no injury has become evident*— Baker and Porter (81). Radishes grown in soil containing 250 pounds of DDT per acre, thoroughly washed, and then fed to three-fourths grown larvae of the white fringed beetle (Pantomorus leucoloma Boh«) caused no mortality in 33 days. Germination of cotton, corn, peanut, oat, and cowpea seeds was not affected by treating tnem with a 50 percent DDT dust before plant- ing. Austrian winter peas, peanuts, rice, sweetpotato, white potato, cotton, corn, cowpea, soybean, radish, and blue lupine have been grown in soil treated with various dosages of DDT up to 100 pounds per acre, and in some cases up to 250 pounds per acre, without visible injury. On the other hand, injury to young rye plants, consisting of redden- ing of foliage, twisting of leaves, poor growth, and dying of some plants, occurred in pot and field-plot tests in which DDT in dust or emulsified form was used as a soil insecticide at rates of 10 to 250 pounds per acre. Emulsions caused very pronounced injury even at the 10-pound dosage. The injury caused by the dust treatments was slight at the 10-pound dosage but increased with the dosage.— Packard (285 ) . Eight applications of 5 percent DDT in light summer spray oil, average about -g- gallon per acre, made by hand atomizer from June 6 to August 1, did not injure strawberries, asparagus, muskmelons, mangels, onions, kale, broccoli, cabbage, eggplant, squash, cucumber, peas, let- tuce, turnips, tomatoes, carrots, beets, corn, beans, lima beans, or potatoes. On soybeans (Bansii) there was definite burn, which was probably due to the oil.— Gray (188 ). The germination of rioe seed was not materially affected by suspen- sions of 0.1 to 100 p.p.m. of DDT» Growth of microorganisms common to soil was not significantly affected by water suspension of 10 and 100 p. p.m. of DDT. Soil pretreated with a DDT-oil emulsion (5 percent DDT and 0.5 percent emulsifier in No. 2 Diesel fuel oil applied at the rate of 1 part to 20 million parts of water) supported growth of rice and barley comparable with that produced on similar untreated soil.— Broyer (97). A pple . A moderate amount of foliage spot-type burn followed the fourth" application of DDT in oil (2 oz. per 100 gal.) on Delicious, but not on Jonathan or Hubbardson. No similar injury was produced by lead or by oil-nicotine sprays on comparable trees in the same orchard.— Cleveland (114). -19- Gesarol AK-20 spray in repeated applications caused no perceptible injury to apple foliage or fruit.— Conklin (116 ) ♦ Aside from some browning of the foliage late in the fall, there wa6 no apparent injury from any of the WT sprays or dusts tested.- Anon. (17) • Citrus. In none of the field experiments made with DDT, either dissolved in oil or used in other ways, was the slightest indication found of injury to the trees* Pour navel orange and four lemon trees were sprayed seven times from March to December 1944 with each of the following treatments! (l) 1 3/4 percent of light medium oil, (2) 1 3/4 percent of light medium oil with 4 percent of DDT in the oil, (3) 3 per- cent of kerosene, (4) 3 percent of kerosene with 4 percent of DDT in the kerosene, and (5) Gesarol AK-20 at 10 pounds to 100 gallons of water* The repeated light medium oil sprays caused serious defoliation and dead wood on the 14-year old orange trees but little damage to the 5-year old lemon trees* In neither case, however, was the damage greater on the oil-DDT- sprayed trees than on the oil-sprayed trees* Neither the kerosene nor the kerosene-DDT caused any discernible in- jury to either the orange or the lemon trees* Likewise, no injury to the bark below the soil line was observed when the soil was removed and the trunks were scraped on February 8, 1945» The repeated treat- ments with Gesarol AK-20 also caused no deleterious effects*— Ebeling (142)* Corn . A 3-percent DDT dust interfered with growth of the corn.— N. J. Agr. Expt. Sta. (275 ). Grape . DDT-pyrophyllite (20-80) was used at the rate of 1 pound of DDT in 100 gallons of water plus J- pound of soybean flour. The spray was applied at the rate of 200 gallons per acre on July 15 and 27* The entire vineyard was treated with the DDT spray on August 9* Most of the spray was directed toward the upper surface of the leaves to avoid spraying the fruit. There was no injury from DDT sprays to foliage.— N* J* Agr. Expt. Sta. (275). Peach . Three applications of 2 pounds of Gesarol A-20 per 100 gallons caused no damage to peach foliage.— Underhi 11 (349 ) » Pear. Dormant misoible oil containing IDT, applied as a dormant spray to give 5.12 ounces of DDT per 100 gallons, caused no adverse effect on buds, bloom, foliage, yield, or fruit size.— Cleveland (114). Potato . No harmful effects on foliage were noted. In one test DDT-treated potato plants appeared more vigorous, larger, and darker green than those treated with other materials. Early blight lesions were not significantly reduced with DDT. — Tate et al. (342). -20- Squaflh . Heavy applications of 2-percent DDT dust at weakly inter- vals killed squash plants.— Underhill (349 ) ♦ Young squaoh and pumpkin plants were severely stunted and young cuoumber plants were stunted to some extent by a 3-percent DDT dust* The acorn squash was more susceptible than any of the other varieties. —Tate _et &!• (342 ) • A 10-percent DDT dust injured squash plants.— Haseman (203 ) • Wheat . Dosages as high as 0.2 percent by weight of technical DDT showed no injurious effects on the viability of seed wheat containing 12 percent of moisture. The treated samples of wheat were examined once a month for 4 months*— Cotton et al. (120) . Effect of DDT on Fungi DDT at 3/4 pound per 100 gallons of water was not effective as a fungicide for early blight of potatoes.— Heuberger (207 ) . DDT is not a fungioide.— Horsfall (214 ). DDT SPRAY RESIDUES AND THEIR REMOVAL DDT toleranoe on foods A formal toleranoe of 7 mg. per kilogram for fluorine on apples and pears has been announoed. An informal tolerance of 7 mg. per kilogram for lead on apples and pears has been recognized for several years. "In view of the agreement among the toxioologists concerning the quantitative relationship of the toxicity of DDT to that of lead and fluorine, this iFood and Drug] Administration has conoluded that during the ooming year it will not be its purpose to inaugurate regulatory action against commodities containing 7 mg./kg. or less of DDT."— Dunbar (140 ) [l p.p.m. r 0.007 gr./lb. and conversely, 0.01 gr./lb. = 1.42857 + p.p.m.] -RCR * Suggestions are presented on the use of DDT on various food crops so as to avoid a DDT residue of 7 p.p.m. or more.— Geigy Co. ( 174 ) . Residues on fruits and vegetables At Winchester, Va», Stayman Winesap apples that had received 5 applications of DDT at the rate of 1 pound per 100 gallons of water (4 pounds of 25 percent DDT in third to seventh covers) bore a resi- due of 0.042 grain of DDT per pound. Washing with 1.3 peroent of hydro- ohlorio acid reduced the residue to 0.037 grain per pound; washing with -21- sodium silioate 75 pounds and soap 1 pound per 100 gallons reduoed it to 0.027 grain per poundj washing with trisodium phosphate 10 pounds per 100 gallon?, reduoed it to 0.034 grain per poundj and brushing in a Trescott machine left the residue at 0.041 grain per pound.— Hough (217} . Preliminary tests at Vineennes, Ind., indicated that DDT residues on apples may be difficult to remove by either brush machines or flo- tation-type washers. Soaps, oils, wetting agents, and strong alkaline solutions had little effect, and none removed as much as half the resi- due. Similar tests at Yakima, Wash., confirmed these results. A maximum of approximately 60 percent of the DDT spray residue was re- moved by using 2 percent of oil in water followed by a wash in a wetting agent to remove the residual oil.— Baker and Porter (81). Two ounces of DDT per 100 gallons of oil, applied 4 times to July 17, produoed 0.0040 grain of DDT per pound on harvested Delicious apples, and 0.0045 grain per pound on Hubbardsons.~Cleveland (114). Washing tests indicate that it is difficult to remove DDT spray residues from apples and pears. Solvents commonly used for the removal of arsenical residues have no aotion on the DDT. Kerosene and heavier petroleum oils dissolve the DDT residue but redeposit it evenly in the oil film that remains on the fruit as it leaves the machine. Detergents appear to show greatest promise for removing DDT residues. In commercial washers the most effective results were obtained when apples or pears were processed in an overhead food machine, in which water (95°F.) con- taining a wetting agent such as Yatsol or Triton 720 was used. Residues of 0.111 grain of DDT per pound on apples were reduoed to 0.047 grain. Apples with 0.06 grain per pound were cleaned to 0.055 grain. Pears, however, that carried 0.042 grain per pound were cleaned only to 0.037 grain. When the wetting agents were added either to acid or to sodium silicate, similar results were obtained. Silicate may prove more effec- tive for cleaning apples after they become waxy in storage.— Chi Ids and Robinson (ill ) • DDT residues on apples from experimental plots were as follows: Two samples from the Pacific Northwest, 2 and 7 p.p.m.; three samples from the Middle West, 5 p.p.m. each; and two samples from the East 4.5 and 6 p.p.m.— U. S. Food and Drug Admin. (355) . DDT sticks to apples much tighter than does lead arsenate and is, therefore more difficult to remove. Apparently it goes into solution in the waxy covering of the apple. To remove the DDT it is almost necessary to take the wax off the apple. On the other hand, DDT does not build up so heavy a residue on apples as lead arsenate or the other insecticides used. Three cr four applications can be made without building up a serious residue.— Annand (74). -22- Analysea of pea pods and kernels from plots treated with DDT Indi- cated the presence of DDT on the pods, but its absence on the kernels* The amount of DDT present on the pods was proportional to the percent- age of DDT used,— Lange (241 ) . Eight applications of 5 percent DDT in light summer spray oil — average about -J- gallon per acre— were made to ■various vegetables (^ acre) by hand atomizer from June 6 to August 1. The kale was fed to chickens from June throughout the summer and all the vegetables were oonsumed by the family and others, with no ill effects. The DDT residue on the beans (Blue Lake) at the time they were canned was 0.029 grain per pound. No other residue analysis was made. --Gray (168) . DDT residue on fruits, vegetables, alfalfa, and olive foliage and fruit was determined by extracting with benzene and dehydrochlorinating with alcoholic sodium hydroxide. Alfalfa treated twice with 3-percent DDT dust at the rate of 28 pounds per acre-application bore a DDT resi- due of 29 p.p.m. (fresh weight). Bartlett pears sprayed with 5 pounds of A-20 per 100 gallons of water bore DDT residues of 0.5 to 3.7 p.p.m. On pears sprayed with 2% quarts of SH-20 per 100 gallons of water the DDT residues ranged from 1.7 to 6.1 p.p.m. The DDT residues on some products were as follows : On walnuts, 13 and 43 micrograms per square inoh of surface after 1 and 2 sprays containing 5 pounds of 20-percent wettable DDT powder per 100 gallons of wateri on small green tomatoes 8 p.p.m., and on ripe tomatoes, average weight 50 grams, not over 0.5 p.p«m. after 4 sprays containing 5 pounds of 20-percent wettable DDT powder plus 6 ounces of blood albumin per 100 gallons of water. Weathering of DDT residues Field tests conducted during the past summer have indicated that DDT deposits on plants do not have the residual aotion anticipated as a result of tests on household insects. Deposits have been reported effective over a period of months in indoor tests, but under outdoor conditions they generally have remained effective for not more than 14 to 18 days. This was found to be the oase in certain tests with the Japanese beetle on linden trees, with cabbage caterpillars on cabbage, and with the codling moth on apple. Apparently some factors in the outdoor environment decompose the DDT or remove it from the foliage. Moisture and sunlight are generally considered the two most important factors in outdoor weathering, but it is possible that heat may be a factor on the upper surface of foliage. Tests to determine the action of sunlight on the toxicity of DDT residues were not successful be- cause of extensive periods of cloudy weather. After a few preliminary trials it seemed more practical to expose sprayed glass plates to an ultraviolet lamp so that different exposure periods could be used. It was recognized, of course, that this type of radiation is only a frac- tion of the spectrum of sunlight, but it was felt that some preliminary information of value might be obtained. The ultraviolet source was a -23- 30-watt, germicidal lamp giving a wave length of 2,537 angstrom units, whioh is a wave length normally filtered out of sunlight by the earth *s atmosphere* Recrystallized DDT (s*p. 108°C*), as well as several samples of plant-run material (s*p* 84-90 C*), was deposited on glasa plates from acetone solutions and aqueous dispersions prepared by different methods* After exposure to ultraviolet light for various periods, each plate was introduced into a cage containing house flies in suoh a way that all flies could and did contact the plate* Treated plates that were unexposed to the light affected the flies in 10-15 minutes, but exposure to ultraviolet rays caused a loss in toxicity in proportion to the exposure* Residues of DDT deposited from solutions could be rendered nontoxic to flies by a 3-day exposure to this lamp* There seemed to be no difference in the three samples with regard to loss of toxicity, but there was some difference between the compositions used* The presence of the inert material in the dispersible composi- tions seemed to retard the rate of decomposition below that oocuring with residues from solutions, and, in general, the smaller the particle sise the more rapid was the rate of decomposition* This apparent de- composition of DDT as a result of exposure to light is of great interest and importance with regard to the residue problem* It is possible that weathered residues may have little or no toxioity to man and domestic animal s»~Goddin amd Swingle (179 )* EFFECT OF DDT ON YJILDLIFE The danger of DDT upsetting the balance. of nature is emphasized. — Teale (345) • An anonymous (31) writer called attention to Teale* s article aad deplored the idea of a world free of insects* DDT will prove a valuable boon in many ways but it can be an extremely dangerous boomerang un- less proper precautions are taken*— Conant (115 ) * An editorial quotes Teale and Pough on the dangers to beneficial insects and birds from the widespread and indiscriminate use of DDT— Anon* (66)* The 40-acre watershed of a small reservoir in Pittston, Pa», was treated at the rate of 5 pounds of DDT in 5 gallons of oil per aore* Three days later, after 0*75 inch of rain had fallen, an analysis of water samples from the reservoir indicated less than 1 part of DDT in 100 -24- million parts of water. In the same area limited observations were made on the effeot of 33DT on forest fauna in general* There was no evidenoe of mortality of bird life, but some of the fish and bull- frogs in the reservoir were killed* Most speoies of insects were greatly reduced in number, but 3 days after the spray had been applied enough specimens of most speoies remained to repopulate the area.—Dowden _et al . (136) j Craighead and Brown (126 ) • In Canada one 8-aore area was sprayed by autogiro with a solu- tion containing 10 percent of IDT in oyolohexanone and light petro- leum oil at the rate of 6 pounds of DDT per acre* Another area of the same size was similarly sprayed but at the rate of 4 pounds of DDT per aore. Very little significant difference of effects was notioed between the two areas* Along the lake shores and in quiet pools a few minnows were killed by contact with the oil film when they broke through the surface to feed upon insects brought down by the spray* In the stream the emulsified DDT solution became too diluted to be toxic to minnows or speckled trout* However, speckled trout seem to be more sensitive to DDT, as any that fed on poisoned insect larvae and adults falling into the stream were killed* Aquatic inseot lar- vae that remain submerged in quiet waters were not affected by the DDT spray. However, mosquito larvae and suoh surface forms as water stridors and whirligig beetles were readily killed. In the streams, where the solution becomes mixed with the running water, or lodges under partly submerged rocks, the larvae and nymphs of aquatic in- sects, such as the dragon fly, damsel fly, may fly, caddis fly, stone- fly, midge, cranefly, blackfly, beetle larvae (Dytisoidae, Psephenidae), and fishfly (Sialldae) nay be completely eliminated* Crayfish and tad- poles were readily killed by contaot with the spray or by ingesting contaminated food* As these are important sources of fish food, their destruction would no doubt have an unfavorable influence on fish sur- vival within the streams* Clams, snails, and leeches were not affect- ed by the sprays* The cyolohexanone and the oils used in the sprays were not in themselves toxie*— Ross (30 6) • In field experiments with DDT mosquito larvicides, BDT in con- centrations sufficiently high to kill subsurfaoe feeding larvae was toxic to the following three speoies of fish: Blaok Bass*— A spray of diluted kerosene emulsion containing 0*1 percent of DDT proved fatal within 3 day6 after application* Catfish*— In a pond sprayed with diluted oil emulsion containing 0*2 percent of DDT many catfish were dead 2 days after treatment* Salt-water minnows*— Dead fish were found in salt-iaarsh test holes 2 days after treatment with a oolloidal solution of 1 part DDT to 4,000,000 parts of water. -26- DDT was most toxic to goldfish -when in colloidal dispersion, less toxic as a surfaoe application in the form of an oil emulsion, and least toxic when applied as a dust. In each case, however, the toxici- ty was sufficiently high to warrant caution against th© use of DDT on mosquito breeding waters where fish that are worth preserving prevail. DDT also killed water snakes, turtles, toads, and many species of aquatic insects. Aquatic plants or land vegetation growing near the treated water areas showed no injury when they were sprayed or dusted with the DDT larvicides. — Ginsburg (178); N. J. Agr. Bxpt. Sta. (275) . In Connecticut a DDT spray applied to sweet grapes (New York Muscats) did not protect them against orioles and blue jays which con- sumed all the crop not protected by muslin.— Bromley (96) . In Maryland 117 acres of the Patuxent Wildlife Refuge were doused with DDT mixed in an oil solvent and sprayed from an airplane. Experts of the Bureau of Entomology and Plant Quarantine (Department of Agri- culture) and the Fish and Wildlife Service (Department of Interior) predicted that every insect in the area would be killed. But of more importance, they hoped to learn what quantity of the deadly DDT oould be used for pest control without upsetting the delicate balance of wildlife. Careless use of DDT on mosquitoes, for example, might elimi- nate ducks and geese. Preparations for the experiment started almost 2 years ago. The location of every bird's nest, anthill, and mouse hole in the area was noted. Trays were placed to catch the dead in- sects; small animals were trapped in boxes. Stretches of the Patuxent River were netted off and fish counted. The experiment will oontinue for another year before results are known. Surviving life in the treated area will then be compared with census figures for untreated control areas. Adding incentive to the experiment is the widely held belief that post-war air traffic will bring multitudes of foreign in- sect pests.— Anon. (57) and Birchfield (84). Fish and Wildlife Service observers will be present this summer at large-scale experiments in Pennsylvania and Maryland and in the Province of Ontario, Canada. Additional laboratory experiments as to the effect of DDT on various species of animals are underway at the wildlife researoh laboratory at Patuxent.— Anon. (55). n DDT has been found to be highly toxic to bees, both as a contact insecticide and as a stomach poison. If DDT ever comes into general use as an insecticide, it conceivably might upset the balance of natur- al conditions by destroying the pollinators that produce a majority of our food crops. Agricultural practices should be regulated to prevent the destruction of bees and other pollinators."— Anon. (43). -26- PRODUCTION United States The Pennsylvania Salt Manufacturing Co., Philadelphia, Pa,, announoed on February 14, 1945, that it nad completed installation of facilities for the manufacture of DDT on a commercial scale and that production had begun.— Anon. (21) • DDT was being made early this year by 13 producers and production must now [March, 1945J be close to 2,500,000 pounds monthly as compared with the starting output of 1,000 pounds in April 1943.— Stenerson (336). At present fApril 1945] United States is producing more than thirty million pounds of DDT per year, practically all of which is being used by the armed forces in one form or another. Unless wide insect control projects are developed in the postwar period, normal consumption of DDT for regular civilian uses is estimated to be a small fraction of this tonnage. -r-Peaker (291 ) . The DuPont Company first made DDT at an experimental plant at Cleveland, Ohio, and the first lot, 500 pounds, was shipped overseas shortly after American troops landed in Italy.—Anon. (38). Sweden In March 1945 commercial production of DDT was to be taken up by the a/B Mo och Domsjo at its Domsjo plant.— Anon. (37). DDT, introduced into Sweden in 1943 as Gesarol, has been used principally for plant protection, although experiments are under way to develop products for veterinary and human use. Between 60 and 80 tons were consumed in 1944, both of the Swiss type and the cheaper Swedish type.— Anon. (59). ALLOCATION The War Production Board relinquished all oontrol over DDT in September 1945 but it is of interest to review the sibiation during the time covered by this digest (January- June, 1945) • According to a stat~ ment issued January, 1945, by the U. S. Department of Agriculture, the armed services will need all available DDT. For many agricultural pests suitable inseotlcidal mixtures and dosag©6 have not yet been worked out and possible harmful effects of DDT insecticides on soils and plants are not fully known .--Anon. ( 12 ) • On February 12 the War Production Board announoed that a limited quantity of DDT* could be obtained directly from suppliers without direct e- -27- WPB authorisation. DDT producers have been instructed by the WPB, how- ever, in distributing the ohemioal to give consideration to work carried out under the supervision of experienced investigators, aimed at de- termining the suitability of DDT for agricultural and other oivilian uses.— Anon. (20) • In February 1945 WPB emphasized to the DDT Producers Industry Advisory Committee that DDT will be released exclusively for experi- mental and research purposes, and that placement of orders for other insecticides should not be based on the supposition that DDT will be available for commercial U3e in 1945. — Anon. (18 , 29) . DDT is scheduled for large-scale government tests and a limited amount will be available for civilian experiments this year. — Anon. (22 ) in February 1945. The War Production Board holds the view that the total production of DDT over the balance of the year will be required exclusively for military uses.— Anon. (28), in March 1945. Small amounts of DDT have been made available by WPB for experi- mental use in agriculture and other civilian fields. Production, which is increasing, is channeled for government use at present (March 1945) • — Anon. (34, 56). DDT civilian allocations, which will be limited to research and experimental work, now are controlled by War Production Board through Paragraph F, General Allocation Order M-300. To be eligible, experi- ments should be supervised by competently trained and experienced in- vestigators, WPB announces. Other eligibility factors are "the type of experimentation proposed and whether it will contribute to the knowledge and development of the use of DDT, including (a) chemical and physical characteristics, (b) pharmacology, (o) toxicology, (d) com- patibility with other materials, and (e) formulation of insecticides. 1 * Prospective experimenters will be allocated a stated amount of material. The producer then may go ahead and supply the DDT, but WPB emphasizes that "where a large quantity is requested, careful scrutiny should be exercised to see whether appropriate and adequate checks are to be main- tained. The results of these large-scale tests should be recorded and appraised by competently trained investigators •" The producers 1 alloca- tions are for material to be distributed between February 15 and May 15, 1945.— AIF Assoc. (67). On March 26, 1945, it was announced that release of DDT for general use in agriculture was unlikely in the near future. Tests with DDT against more than 170 different species of insects prove it to be defi- nitely more effective than other insecticides currently used for control of some 30 pests; against 18 other insects, DDT insecticides were about equal to those ordinarily used, and against 14 important destructive pests, including the boll weevil, they were found to have little or no -28- effeot. The performance of DDT inseoticides is outstanding against oertain pests, but is not a cure-all or panacea for all insect prob- lems*— OPD Washington Bureau (282 ) * War Production Board is reiterating ito warning that DDT released to civilians this year is solely for experimentation. Nevertheless, a WPB spokesman reveals "several instances where it would appear that efforts have been made to interpret the regulation to cover more than purely experimental programs*" He adds that *in our efforts to con- tinue to justify quantities of material for agricultural experiment (which must be taken from military supplies) we must have the assur- ance that the real intent of regulations is being observed. If DDT released frr experimental purposes is used otherwise, it is contrary to regulations and may require the attention of our Compliance Division, — AIF Assoc (68 ) • Additional small amounts of IDT, the war-developed insect killer, may be made available for agricultural and civilian experimentation during the last half of the year, the Chemicals Bureau of the War Produc tion Board stated. At the present time [April 1945] blanket quanti- ties of DDT are being released by produoers for distribution to per- sons, firms, or government agenoies engaged in research or experimenta- tion directed toward the eventual use of the insect killing chemical in commereial pest control. Only trained and experienced investigators are allowed supplies for suoh work, WPB emphasis *d, WPB warned the industry that if DDT leaks out for any but striotly experimental work, oomplete allocation oeotrol of the chemical may be neoessary, requir- ing considerably more paper work by both the government and industry* —Anon* (44 ) • The first approved commercial use of DDT was announced May 29 by Chemicals Bureau of WPB* Upon request of War Pood Administration a limited supply of teohnical grade DDT has been made available in Oregon only for use against the potato tuber flea beetle, Rotenone* ordinarily used for this purpose in combination with oaleium arsenate, is net available, and there are no other effeotive substitute materials for this purpose,— Anon, (68); also U* S, UPB (359 ) * At the December 1944 meeting ef the California USDA War Board Economio Poisons Advisory Committee, it was the unanimous opinion that requests for DDT for pest control purposes should be allotted through economic poisons' registrants who have adequate facilities to oarry on the difficult grinding and other procedures to prepare dusts and sprays, and who agree to use adequate safeguards. The Committee readily en- dorses the quantities needed to oontinue reputable experimental and pilot development work, and desires to encourage conservatism until ex- perimental work has been oompleted* -29- For those instances where it is accepted that there is not too great a hasard, ttere should be a backlog allotment of DDT for use L California in case other pest control materials are not available for specific purposes. Suggested backlog counts as ind^teTto be allocated for use as needed were estimated as follows: Pounds Grape leafhopper on grapes before blooming 100,000 Citrus thrips on citrus ••••••••••••••••••••••••• 20,000 Codling moth on walnuts ••••••••* •••• 10,000 Onion thrips on onions ••••••■ ••••••• 50,000 Cankenvorms on prunes ••••••••••• ••• 10,000 Worms on vegetable seed crops grown for seed (not including onions) • • 15,000 Thrips on dry beans ••••••• ••••• 15,000 Protection of animals from pests, including spraying dairy barns to reduce flies ••••••••• 25,000 Experimental purposes •••••• • •••• * 50,000 Pear thrips infestations are reported to have been extensive in 6 or 8 counties of California for the past 2 years and a backlog of at least an additional 110,000 pounds for this purpose would seem reason- able and desirable. Therefore, California agriculture could use approx- imately 400,000 pounds or more of DDT in 1945.~Cox (121 ). COST Early lots of DDT cost the government $1.60 a pound, later #1.00, and effective January 1, 1945 Du Pont announced a price of 60 cents.-- Peaker (289 ) j also Anon. (8) and Stenerson (335 ) . Transportation regulations The TJ. S. Interstate Commerce Commission in April 1945 issued list CFR 73 revising the transportation rule on DDT, classifying the material as poison B, applying sections 352 and 361 on exemptions and packing, re- quiring a poison label, and setting a 200-pound maximum for shipment by express. On June 29, 1945 the Commission issued an order in Dooket No. 3666 which removed DDT from the regulation, because as a result of an investigation by the U. S. Publio Health Service it has been determined that this material is not sufficiently poisonous to be considered a class B poison under the regulations.— U. S. Interstate Com. Commis. (555) . PATENTS AND TRADE-MARKS Patents On April 20, 1943 Canadian patenx 411,926 covering a devitalising composition was granted Paul Muller (267 ) • This patent is similar to LIBRARY erATE PLANT BOARD -30- U. 3. patent 2,329,074, covering DDT and analogous compounds granted September 7, 1943 to Ifciller and assigned to J. R. Geigy A. G., Basel, Switzerland* On August 25, 1942 Belgian patent 446,935 was granted E. Merok (255) • This patent oovers insecticides consisting of diphenylethanes oT'aiphenyl ethylenes of the general formula (RR»X)C-C-(X»Cl2), where R and R* are phenyl or substituted phenyl radicals, and X and X* are nydrogen or chlorine or are eliminated with formation of a double bond between the two aliphatic carbon atoms. In January 1946, it was reported that Geigy Company, Inc, New York, were negotiating agree- ments for licensing of inseotioide firms under U. S. Patent No. 2,329,074, which covers the sale of ODT-containing insecticides. The licenses are nonexclusive and nontransferable, and besides involving a royalty payment of 5 percent of the net sales price also provide that any improvements developed in the use and application of TOT in- secticides by the lioensor shall become the property of the Geigy C ompany • —Anon • ( 5) • Trade-Marks The Monsanto Chemical Company announced on March 20, 1945 that it would market DDT under the name "Santobane* and if formulations of DDT are produced the same term will be used and with it an identifying letter or number. At present Monsanto makes only the basic chemical. Volume production was begun September 1944.— Anon. (42). The following symbols and names have been used to designate DDT or compositions containing itt GNB, GNB-A, GNB-A-DDT, Anofex, DeDeTane, DeDiTox, Gesarol, Guesarol, Gesapon, Guesapon, Gesarex, Guesarex, Gyron, Ixodex, Neocid, and Neocidol. The composition of these is given.— Roark (302). Some of the preparations containing DDT used in Sweden are Alitox, Boxol, and Rotoxol.— Ahlberg and Mathlein (69) • DDT IN AEROSOLS At the Virginia Truck Experiment Station DDT gave excellent con- trol of the larvae of the diamondback moth on kale, collards, and broccoli when applied in a very fine mist in combination with methyl chloride and oil in a form oommonly referred to as an aerosol. — Walker (366 ) . Aerosols produced by heat Fog generators, invented to screen allied troops, ships, and mili- tary installations in World War II, are being used to disperse DDT over -31- fields, orchards, and vineyards. In 15 seoonds to 2 \ mixutes an acre is blanketed with an odorless, impalpable but opaque mist, harmless to man and all other warm-blooded animals, that destroys every injurious inseot. A complete kill of oitrus thrips, grape leafhoppers, flea beetles, oabbage loopers, and three or four other troublesome pests can be reported without reservation. Cattle and barns are freed of flies by this very fine fog. The oost is trifling and the applica- tion incredibly easy and swift. The fog is made by feeding DDT in oil solution into a current of steam. The maohine is made by the Todd Shipyards Corp. of New York City. A report of tests of a DDT-oil fog in the Salt River Valley, Ariz.— Anon. (49); also Vorhies and Wehrle (364). Toxicology of DDT aerosols Reports on this subject are given in the section en PHARMACOLOGY by Neal (272 , 275 ) , and von Oe-ctingen _et a_l. (363 ) . USE OF DDT BY PEST CONTROL OPERATORS Since the general public lacks special knowledge of insects and con- trol materials and procedures, it seems logical to expect that the pest control operator will be called upon to an increasing extent to under- take this work. Therefore he should endeavor to keep informed of de- velopments from research on DDT insecticides.— Twinn (347 ). Pest control operators should have no fear that DDT will put them out of business.— Anon. (27); (15). At the third annual Canadian Pest Control Operators 1 conference at the University of Montreal, February 20, 1945, a program of cooperative research on DDT by the Canadian Department of Agriculture and the Canadian Pest Control Operators* Association similar to that in operation in the United States was discussed.— Anon. (46). At the ninth annual Pest Control Operators* conference held at Purdue University, January 15-19, 1945, Maj. Franklin Sherman of the U. S. Army Sanitary Corps, reported on the decontamination of enemy territory before our troops set foot upon it. In the Philippine campaign the island of Leyte was covered with DDT before the invasion commenced.— Anon. (15). REVIEWS AND POPULAR ARTICLES Reviews of information on DDT have been published by: Anon. (13), Bishopp (86), Buxton ( 100 ), Cox (123 ), Heilbron (205 ) 9 Wasioky and Unti (367 ) and West and Campbell ( 369 ). -32- Some of the popular accounts of DDT are "by: Anon. (1, 32, J58, 39, 40, 45, 48); Anon. (51); AIF (j>3) ; Ananda "R"auTT2) ; Armagnac (76) ; Ayars (79) ;""B"aldwin Labs. (82); Bishopp (85J7 Callan (102 ); Cardoso (106 , 107); Chapman (109 ); Childs (lTO*); Cooper (TT7) ; Cox (121); Daviault (127); Dove (138 ) Es"sTg (143 , 144)"p?rey (l6lTT"Funk (163); George (177); Goodhue (180); HalTTl£7) ; Hambidge ( 198 , "199 ); Kirch er T23*5) ; Klumpp and Rioe (237 ) ; Knowlton (238 ); McClintock and Fisher (250 ); McNeill (2*517 J Mallis (252TT"Michelbacher (256); Morgan (265); Norris {Z76j; Peede (29TJ7 Pope (295 ); Pritchard (298); Reed (299); Rohlf ( 304 ;) Ross~T307) ; Sealy-Fisher (310 ); Severin (312) ; Simmons ( 317 , 318 ); Stafford (328); Stark (332); Tate (341); Twinn (347); Omhauer (348) ; White (371); Whitney (374); Wolman (380). Brief mention of DDT is made by: Anon. (7, 10, 14, 24, 52, 54), AIF (64); A uchter (77, 78); Borden T89JT (ftry TTl8j7 Davis (128); Degering (132); Kirk (236); Markwood (25557 Mel eney (7{>4*) ; OPD Obs erv"er"( 281) ; Patterson (288); "S*ch*if feres (309jTSmith (323); StagTT329). A chemist named Philippe Auerbach claims to be the inventor of DDT powder»~United Press (350 ) • Holland (213 ) has given a popular aooount of the aerosol bomb and the use of DDT in it» INSECTICIDAL VALUE The publications abstracted in this digest record the results of tests with DDT preparations on 325 identified speoies of insects and other arthropods belonging to 18 orders and sub-orders, 99 families, and 220 genera. There is no relationship apparent between the classi- fication of the insect and its susceptibility to DDT. Sometimes differ- ent speoies in the same genus, e.g. the pepper and boll weevils, react differently to the same formulation of DDT* As a matter of convenience in handling a large mass of data the generio names of the insects are arranged alphabetically under the family names whioh in turn are arranged alphabetically under the order or suborder. These larger groups are arranged aocording to increasing complexity of structure— Orthoptera, Coleoptera, Lepidoptera, Hymenoptera, etc* -33- NBHATODA Anguillulidae Anguilluline dipsaci s Dlpylenohua dipsaol filiplus (Kuhn) Filipjev, the ffigg wiww — A single application of 10 liters of water containing 2 percent of "Guesarol" and 0.2 percent of Tinopol oil per square meter is very effec- tive in sterilizing eelworm-infested soil. Guesarol is a powder contain- ing 5 percent of DDT.— Geigy Colour Co., T td. (166) . THYSANURA Lepismatidae Lepisma saccharina L., the silverfish Spraying with refined odorless kerosene containing 5 percent of DDT killed silverfish in a wheat-sample room and the first floor of a flour mill, and the residual effect of the spray caused the death of invading silverfish for many weeks after treatment. In another test, two 100-pound cotton hags, one treated by dipping in a 5-percent solution of DDT in carbon tetrachloride and the other untreated, were filled with flour and stored next to each other in a mill basement. In a few hours the untreat- ed bag was literally covered with silverfish, while not a single insect was observed on the treated bag.— Cotton et al. (120) • DDT residues in buildings sprayed with kerosene-benzene solutions containing 3, 4, or 5 percent of DDT killed silverfish.— Ross (306) . Tests on silverfish have not been satisfactory in experiments where conditions have not been well controlled.— N. J. Agr. Expt. Sta. (2 75 ). Silverfish succumbed to Gesarol A-3 dust when their runways and trails were dusted.— Parker (287 ) • Thermobia domestic v?ack., the firebrat Deobase sprays containing 0.2 percent of DDT, together with pyrethrum or other paralytic agent as used for houseflies, gave excellent control of -34- firebrats -when it was atomised into a Peet-^rady chamber. A talc dust depositing 20 mg» of EOT per square foot, or a Deobase-mineral oil spray leaving a residue of 80 mg. per square foot, gave complete con- trol of firebrats oonfined on treated surfaces for 24 hours. Residues (80 mg« per sq« ft») deposited from solutions in Deobase, cyclohexanone, or toluene, and those from aqueous suspensions, killed the insects, but more slowly than dusts.— Goddin and Swingle (179 ) . ORTHOPTERA Acrididae Camnula pelluoida (Scudd.), the clear-winged grasshopper DDT dusts and sprays gave good results. — Packard (285 ) . Melanoplus bivittatus (Say), the two-striped grasshopper See M. roexicanus .-Parker (286 ) ; Packard (285 ) • Melanoplus differentialis (Thos.), the differential grasshopper A 3-percent DDT dust (A-3) gave no indication of being toxic to differential grasshoppers when lightly dusted on them. The grasshoppers were swept from alfalfa and held in an insect net with alfalfa cuttings over night •--Smith (324 ) • A heavy infestation of grasshoppers in an alfalfa field treated with a 3-percent DDT dust at the rate of approximately 28 pounds per aore did not appear to be af fected.— Michelbacher et al. (257 ) • Melanoplus femur-rubrum (Deg.) , tiie red-legged grasshopper In dusts cevadine was more toxic than veratridine and both were more toxic than DDT,— ATP (66) . See M. m exi canu s .— Parker (286 ) j Packard (285 ) • M. m exi canu s (Sauss,), the lesser migratory grasshopper The dominant species of grasshoppers present in plots treated with DDT were Melanoplus mexicanus (Sauss.), M. bivittatus (Say), and M. femur - rubrum (Deg.) • No differences could be detected in their reaction to DDT dusts. The effects of DDT were apparent within half an hour after dusting. The grasshoppers became excited, descended from vegetation, and wandered aimlessly about manifesting distress. Many were down on their sides within 3 or 4 hours, but few were found dead the first day. In 48 -35- hours the great majority were either dead or moved only reebly w^ien dis- turbed. Grasshoppers were highly susceptible to DDT in dusts, sprays, and aerosols. Twenty pounds per aore of 15 percent of DDT in pyro- phyllite applied eithej? as a dust or spray reduced heavy infestations of grasshoppers to noneconomio numbers without injury to foliage. Un- less washed off by heavy rains, DDT applied as a spray continued to kill over a period of several weeks, and in this respeot was more effective than dust, which was removed by either wind or rain. Both sprays and dusts exhibited marked repellent effect. Sprayed or dusted plots of l/2 acre or more, on whioh grasshoppers had been reckiced to several per square yard, remained very lightly infested for several weeks although surrounded by infestations of 10 to 25 grasshoppers per square yard. No traoe of foliage injury from DDT was noted at any of the dosages used. Fair to good mortality of grasshoppers was obtained from a single application, at the rate of about 20 pounds per acre, of a bait mixture containing the following proportions t 3 pounds of powdered technical DDT, 100 pounds of wheat bran, 1 gallon of molasses, and 1-1/2 gallons of water.— Parker (286 ) 1 Packard (285) . DDT, at the rate of 16 ounces in acetone solution dispersed with soap per 100 imperial gallons of water, apparently had little effect either as a contact or a stomach poison in a test at Vernon, B. C — Ross (306 ) • Unidentified grasshoppers A 10 percent DDT-pyrophyllite dust reduced the population of grass- hoppers in an alfalfa field.— Li eberman (245 ). A 1 percent DDT-kaolin dust proved ineffective against grasshoppers. —Sen (311). Blattidae Blatta orien tali s L., the oriental cockroach DDT is a contact poison.«— Domenjoz (135). Blattella germanica (L.), the German cockroach DDT was tested in October and November, 1943, and found to give good results at dilutions of 10 and 25 percent. In 1944 two commercial mix- tures, Gesarol A3 with 3 percent of DDT and Gesarol A20, a spray material in powdered form, with 20 percent of DDT, were tested. The 20-percent mixture gave good results, whereas the 3-percent material was not satis- -36- factory. In all tests with this chemical the roaches were down in 12 hours or less, but in many instances were still actively kicking at the end of the tests (96 hours) • "When adult roaches were treated in a dust settling chamber witn the army louse powder (10 percent DDT) 100 per- oent of both males and females were killed in 96 hours. The survival time in hours was 5*2 for males and 17*5 for females. Lethane A-70 roach powder likewise killed 100 percent of both males and females but the survival times were shorter, namely 2*4 hours for males and 7.0 hours for females.— Gould ( 185 ) * Laboratory tests with 3, 10, and 25 percent DDT dusts were con- ducted against the German cockroach in a settling dust chamber. The 3- percent dust gave poor results on both sexes. The 10-percent dust gave a 93-percent kill of males in 30 hours and a 66-percent kill of females in 55 hours, while the 25-percent dust gave 100-percent kill of males and a 98-percent kill of females in the same lengths of time.-- Gould (184). Deobase sprays containing 0.2 percent of DDT, combined witn either pyrethrum, butyl carbitol thiocyanate, or bornyl tniocyanoacetate were found to be relatively ineffective when used in the Peet-Grady chamber against young nymphs of the German cockroach. When Deobase solutions of DDT were sprayed directly on the insects, dilutions down to 0.75 per- cent of DDT killed 100 percent of the roaches in 24 hours, but lower dilutions did not give oomplete oontrol* Certain types of surface de- posits of DDT were found to be very effective against roaohes walking aver then. Residues of from 4 to 40 sag* of DDT per square foot de- posited by the evaporation of toluene solutions caused no mortality within 24 hours, but a deposit of 20 mg* of DDT per square foot, de- posited as talo dust, killed 100 percent of the roaohes. An 80 mg. deposit of sodium fluoride was required to cause a mortality of 92 peroent* A deposit of 80 mg* of DDT laid down by the evaporation of a solution in Deoba3e-mineral oil gave oomplete oontrol of young roaches* Less effective residues were obtained using DDT solutions in Deobase, cyolohexanone, or toluene, and also from aqueous sprays of a water-dispersible powder* These results indicate that dust de- posits of DDT may be much more effective for controlling cockroaohes than residues deposited from solutions or suspensions.— Goddin and Swingle (179). An apartment adjacent to a store was infested with German roaches* Cockroaohes were completely eliminated from the apartment by blowing a 20 peroent EDT-talc dust into all cracks and crevices beneath the linoleum and between flooring wherever openings occurred* Other tests with 3 percent of DDT in kerosene against oockroaches were not satisfactory* — N* J. Agr. Expt* Sta* (275 ) * -37- Not affected by a deposit of DDT on filter paper during 6 days. — Vargas and Colorado Iris (360 ) • Periplaneta americana (L.), the American cockroach ■ ■■ ir ■ in ■ !■■■!- - and cauliflower •— Anon* (49)* Large thrips populations that existed in all plots of alfalfa at the time of dusting were practically eliminated with DDT used in the form of a 10-peroent dust in pyrophyllite*- Lieberman (245 ) • HEMIPTHIA (Suborder HOMOPTERA) Aleyrodidae Trialeurodes abutilonea (Haldeman) One application of a 3-peroent DDT dust (Gesarol A-3) on eggplant was made September 16 at a rate of 40 pounds per acre* One week later the number of nymphs on the underside of the basal leaves averaged 76 *8 per leaf on the dusted plots and 38 *6 on the undusted plots. It is be- lieved the DDT reduced the number of predaceous insects, especially larvae of Chrysopls sp* — Ewart (145 ) • Trialeurodes sp*, greenhouse whitefly A 3-percent DDT dust was effective in the gr ee nh ouse.— Haseaan (203 ) There was some indication that 1*2 percent of DDT in oil applied as a vapo-spray was effective against whiteflies on peas»- Lange (241) ♦ Aphiidae Anuraphi8 roseus Baker, the rosy apple aphid At Vincennes, Ind», early in April 1944, it was noted that trees sprayed with several formulations of IDT in 1943 had very low or no aphid populations, although adjacent trees were heavily infested* In 1944 DDT was slow in eliminating all three species of apple a phi da already pres- ent, but they disappeared by midseason* The apple grain aphid and the rosy apple aphid disappeared earlier from the trees treated with DDT than they did from the untreated trees*— Baker and Porter (81)* DDT has shown promise in the oontrol of apple aphids* — Steiner _et al. (334) . Dormant miscible oil, containing DDT in solution, applied to give 5*12 ounces of DDT per 100 gallons, was inferior to a conventional ovi- cidal tar-petroleum miscible oil in killing the eggs of the rosy apple aphid, but did reduce early bud infestation markedly as compared with untreated checks* DDT in oil permitted multiplication of the spring and early summer population of the aphids much more than the tar-petroleum spray*— Cleveland (114) • -46- Aphis gossypii Glov., the cotton aphid, the melem aphid DDT was not effective and seemed to cause about the sane in or ease in aphids as did calcium arsenate, under the conditions of light aphid infestations that prevailed in 1944 • In field experiments at Tallulah, La., and at Waoo and Bryan, Tex, the aphid populations in plots dusted 3 to 6 tines with DDT were about equal to those in the plots similarly- dusted with calcium arsenate. The addition of 2.5 peroent of DDT to the calcium arsenate used in en experiment at Tallulah caused a greater increase in aphids than undiluted calcium arsenate or 5 percent of DDT in pyrophyllite, but when 1 percent of nicotine was added to the DDT- calcium arsenate the aphids were held in check. In a large-scale ex- periment at Waco the adults and larvae of the lady beetle were reduced 67 peroent in the DDT plot and 70 percent in the oalcium arsenate plot. At Tallulah these predators were reduced 75 percent in field plots dusted with 5 percent DDT and 83 percent in the calcium arsenate plot. — Loftin (247) . The average number of aphids per 10 feet of rows on muskmelon plants dusted with 6 percent of Lethane, 5 percent of Thanite, 3 percent of nicotine sulfate, and 3 percent of DDT, was 329, 639, 586, and 803, as compared with 2,048 for the control treatment .--Wolf enbarger et al. (379 ) . A 3-peroent DDT dust and a spray containing 1 pound of actual DDT in 100 gallons of water were inferior to a nicotine-soap spray 1-800 against melon aphid»— N. J. Agr. Expt. Sta. (275 ). In greenhouse tests 1, 2, and 4 ounces of DDT in Velsicol emulsion per 100 imperial gallons of water gave aphid kills of 80.8 peroent, 95»6 percent, and 98.4 percent, whereas in powder suspension 4, 8, and 16 ounces of DDT per 100 imperial gallons .of water killed 69.9 peroent, 76.6 percent, and 80.3 percent.— Ross (306 ). Eighty hills of cantaloups received two early treatments of cryolite and five applications of either 3-percent DDT dust or 20 percent (Gesarol) spray. An infestation of melon lice developed on these plots and spread to the plots treated with cryolite.— Gould (184 ) • Small, lightly infested cotton plants were dusted with a 3-percent DDT dust (A-3) at the rate of 25 to 30 pounds per acre. There was no apparent control. —Smith (324) • In the experimental applications of DDT to cotton, aphids increased. DDT is the most effective material yet found against the pink bollworm but it causes an increase of aphids.— Annan d (74). Three applications of Gesarol A-3 dust to cantaloup at the rate of 30 pounds per acre were ineffective against aphids.— Ewart (145) • -46- Pyrophyllite diets containing 5 percent of DDT or 5 percent of DOT plus 5 percent of yellow copper oxide completely failed to control the melon aphid in commercial plantings of melons*— Granovsky (187). Aphis pomi Deg,, the apple aphid Gesarol AK-20 spray, 2 pounds with 6 2/3 pounds of wettable sulfur per 100 gallons of water, appeared to prevent heavy buildup of epnid populations on Red Delioious apples in New Hampshire during the 1944 season* Five applications were no better than three, and the Gesarol acted slowly.— Conklin (116 ) • See Bnpoasea maligna •—» Granovsky ( 187) • Aphis 8piraecola Patch, the spirea aphid Gesarol A-3 Dust (3 percent DDT) was applied to Vanhoutte 3pirea fairly heavily infested with aphids, and after 5 days there was little apparent control. One application of a nicotine dust eliminated the infestation within a few hours*— Ross (306) . Cylindrical wire cages were placed over sprigs of spirea infested with aphids and placed in bottles of water. The insides of the cages, the foliage p and the paper toweling on which the cages rested were spray- ed with Gesarol A-20, 0.8 pound in 100 gallons of water. The aphids were apparently uninjured by the DDT.— Fluke and Pond ( 157 ) • Bre v icoryne brassicae (L«), the cabbage aphid A higner population occurred in the plots treated with a dust con- taining 3 percent of DDT or with a spray of 2 pounds of Gesarol AK-20 per 100 gallons of water. At the time of harvest, parasites and predators appeared prevalent in all the plots, and it may be that aphid abundance in the DDT plots was due in part to possible migration of aphids caused by the more succulent and vigorous growing DDT-treated plants. --Allen and Brunn (71). See Trichoplusia nl «— S. J. Agr» Rxpt. Sta* (275 ) . Late cabbage and broccoli were treated with a 3-percent DDT dust and a 20-percent DDT spray. Lioe colonies were present on four plants in the DDT-treated plots, and on 2 in th6 dust- treated plots; there were none on the check.— Gould (184 ) • Chroroaphis juglandicola (Kltb.), the walnut aphid DOT was observed to kill the walnut aphid -when it was being used against the codling moth on walnuts at Linden, Calif. It al- so killed the predators and probably the parasites. Eventually, however. -47- serious infestations of the -pest developed. Apparently DDT remains effec- tive against the predators and parasites longer than against the aphid itself. Thus the aphid becomes established and builds up a large popula- tion before being subjected to its natural enemies. The results of this investigation indicate that more work is needed before any recommendations can be made for the use of DDT as an insecticide on walnuts,— Mi chelbacher £t al. (260) . Eriosoma lanigerum (Hausm.), the woolly apple aphid In the fall of 1944 at Vinoennes, Ind., aerial colonies of this species were common on trees treated with lead arsenate, but absent from trees treated with DDT or nicotine. At Yakima, Wash., it was noted that woolly aphids had become much more common in some apple trees spray- ed with DDT (1 part plus 2 parts of pyrophyllite) than in adjaoent trees sprayed with lead arsenate. Tests made on this species in October with DDT resulted in almost no control whatever. It was only by dissolving the DDT in a petroleum oil derivative, and using an emulsion of this so- lution with a wetting agent, that anything approaching satisfactory con- trol of this aphid was obtained. — Baker and Porter (81 ) • When DDT was used on a block of apple trees it gave sensationally good control of the apple worms but killed off the small parasitic wasps introduced 10 years ago to check the woolly aphid. As soon as these aphids are freed of their natural enemies they increase immediately to dangerous numbers.— Burtner (98). DDT failed to kill the woolly apple aphids, whereas it practically eliminated all the beneficial insects that act as predators or parasites of this plant louse, including at least two species of syrphid flies, lace wings, lady beetles and the very important internal parasite Aphellnus mail Hald. which, after its introduction into the Hood River area in"T928," so reduced the aphid population that this pest has been of minor importance sinoe that time* In the mid-Columbia apple-growing districts, a biological upset of this character is of major importance, sinoe the woolly apple aphid is associated with the spread of a serious canker disease known as perennial canker, Gleosporium perennans , which attacks both trees and fruit. Following the introduction of Aphelinus mall and its establishment throughout the district, aphid populations were so reduced that canker likewise became of minor importance. Any spray practice that would tend to build up the aphid population would likewise lead to a serious increase of canker disease with disastrous results.— Childs and Robinson (111 ) . Macrosiphonlella sanbornl (Gill.), the black chrysanthemum aphid DDT at 1 ounoe per 100 imperial gallons of water gave 100 percent control. The DDT was emulsified by adding to water a solution of 20 grams -48- of DDT in 10 ml* of Triton X-100 and sufficient Velsiool AR60 to make 100 ml.— Ross (306 ). Maorosiphum pi si (K2tb«), the pea aphid Under greenhouse oonditions at Madison, "Wis., a 10 percent DDT-py- rophyllite mixture killed all aphids after 1 day; a 5-peroent mixture after 2 days; and a 1-peroent mixture after 3 days. The mortalities were much higher at 63 -65°F. than at 51°-55°. In tests conducted on the residual effect of DDT "when dusted on pea plants, the residues of the 5-percent and 10-peroent dusts applied 1, 3, 5, 11, 14, and 21 days before exposure to aphids gave 84 percent mortality of the aphids in 1 day and 100 percent mortality in 3 days. In other tests the 1 percent and 0.5 percent strengths of DDT had greater residual effect than did mixtures containing 0.5 percent of rotenone. At Columbus, Ohio, the aphids were tested by use of a bell-jar duster. DDT was very effective and appeared to be more so than derris at comparable strengths. A 0.625-percent mixture killed all the aphids 3 days after dusting.— Dudley et al. ( JL39 ) • Both 5- and 10-percent DDT aerosols applied at 10 pounds of so- lution per acre (lj pound of actual DDT) gave 85 to 99 percent re- duction of pea aphid populations as compared with untreated plots* Ten pounds of aerosol solution oontaining 6 percent eaoh of DDT, cyclo- hexanone, and lubricating oil, 35 percent of acetone, and 50 percent of methyl chloride per acre has given excellent control of the pea aphid.— Ditman (133 ). A dust oontaining 3 percent of DDT gave oontrol as good as the oommonly used rot enone-1 ethane or rotenone-niootine dusts. However, none of these gave entirely satisfactory results and in one instance where the results were especially poor, the grower retreated the whole field with vaporized nicotine.— Walker (365 , 366 ). During August and September in California several mixtures contain- ing oil and DDT were applied to peas as vapo-sprays. From the standpoint of pea aphid control, DDT appears to be fairly effeotive in oil when applied by the vapo-spray machine; the kill is in direct proportion to the amount of DDT present. Combinations of 1.2 percent DDT and 0.05 or 0.25 peroent rotenone were superior to 1.2 percent DDT alone, and about the same as 2.4 peroent DDT.— Lange (241) • Tests were made on acre plots of Alaska peas. A spray of 1 pound of DDT and £ pound of Vatsol OS in 100 gallons of water was compared with a spray oontaining 3 pounds of cube powder (5 peroent rotenone) and £ pound of Vatsol OS. Sprays were applied at the rate of 180 gallons to the acre at 325 pounds' pressure. A 3-perosnt DDT dust was compared with a 0.75-peroent rotenone dust, a 2 percent free niootine-0.5 peroent -49- rotenone dust, and a 0.25 peroent rotenone-1 peroent IDT dust on dupli- cate half-acre plots. Applications were made with a motorized duster, with a 25-foot dusting curtain, at the rate of 45-50 pounds per acre* In sprayed plots initial control was about equal between the rotenone and DDT sprays but after a week the population on the DDT plot began to build up rapidly while the population on the rotenone plots remain- ed low. The 3-percent DDT dust was the poorest treatment and the rotenone-DDT dust next to the poorest. The other dusts gave excellent control. The DDT-sprayed plots gave 90 percent and the DDT-dusted plots 70 percent of normal yield based on the rotenone plots.— N. J. Agr. Expt. Sta. (275) . In laboratory tests in 1943 DDT shov«r a toxicity to the pea aphid comparable to that obtained with rotenone dust mixtures. Results of field experiments at Madison, Wis., did not substantiate these consist- ent laboratory results. For example, in one experiment the application of 5-percent DDT dust with a power duster at the rate of 35 pounds per aore, followed by heavy rains, resulted in 99 percent control after 7 days as compared with 88 peroent for a 0»5-percent rotenone dust contain- ing 2 peroent of a light mineral oil. In this experiment the average yields of shelled peas per aore in five quart er-aore plots were 1,517, 859, and 495 pounds, for the DDT, the rotenone, and the check treatments* In a second experiment, also followed by rains, a 5-peroent DDT dust gave less outstanding results than those obtained with several dosages and strengths of rotenone dust mixtures. In a third experiment, under wet conditions but accompanied by very little precipitation, both the 5- and 10-peroent strengths of DDT were less effective than a dust con- taining 0*75 percent of rotenone and 2 percent of a light mineral oil. —White (373). Field experiments in 1944 indicated that DDT was highly toxic to the pea aphid, but for best results the amount would need to be increas- ed from 3 percent to 4 or 5 percent.— Wilson (376 ) • Careful examination of the ground under hairy vetch at Oregon City, Oreg., disclosed that 5-peroent DDT dust had killed insects of several species. Pea aphids were present in large numbers on some of the plots, but only a few appeared to have been killed by DDT.— Rockwood and Reeher (303 ) . ' Macro slphum solanlfolii (Ashm.), the potato aphid In field experiments tomato plants (7 replications) were sprayed five times with tribasic copper sulfate, flour, DDT (4-2-1-100) or calolum arsenate, lime (4-8-100) • The applications were made with a knapsack sprayer at 10-day intervals starting July 13. Both treatments were about equal against the potato aphid. The general appearance and vigor of the DDT-treated plots was definitely inferior to that of the -60- calcium ar senate-treated plots. The DDT plots yielded 19 tons per acre whereas the caloium arsenate plots yielded 22 tons.— H. J. Agr. Expt. Sta. (275 ) . See Hellothls armigera .-- Tfolf enbarger et al . (379) • Mjyzus perslcae (Sul*.), the green peach aphid In -western Nebraska potato fields the aphid populations on DDT- treated plots remained at a level equal to or lower than that of the check plots. In contrast, the increases on plants treated with sine arsenite were highly significant. In repeated test6 under greenhouse conditions, heavy populations of Myzus persicae were eradicated with- in 48 hours with a 3-percent DDT dust. This species was unable to reestablish itself on suoh plants for some time afterwards. — Tate _et aj. (342) . Aphid populations on potato plants in plots treated with DDT dust or spray remained at a very low level in oontrast to narked increases on plants sprayed witti tine arsenite.— Hill (209) • Khopalosiphum prunlfoliae (Fitch) , the apple-grain aphid Sane as for Anuraphls roseus •— Baker and Porter (81) • Rhopaloslphum pseudobrassioae (Davis), the turnip aphid 8ee Triohoplusia nl .~ H. J. Agr. Bxpt. Sta. (276 ) . Rhopaloslphum rufomacu latum Wilson, the green chrysanthemum aphid Acetone suspensions and Velsicol emulsions of DDT at 2 to 4 ounces of DDT per 100 imperial gallons of water gave 100 percent mortality, but powder suspensions killed only two-thirds of the aphids at 8 ounces of DDT per 100 imperial gallons*— Ross (306) * Sipha flava (Forbes), the yellow sugarcane aphid The aphid infestation was noticeably greater in DDT-treated plots than in plots receiving any other treatments or untreated.- Ingram jrt al . (222) | also Paokard (285) . Unidentified aphids A DDT-oil fog used to oontrol grape leafhoppers in Arisona did not kill aphids.— Vorhies and Wehrle (364) • -51- In an orchard in Buena Park, Calif,, citrus aphids became serious pests after DDT was used, whereas they were of no commeroial ixnportanoe in plots where oil only was used.— Ebeling (142) * Aphids on cole crops and heans were not controlled by eight appli- cations of 5 peroent DDT in light summer spray oil— average about l/2 gallon per acre— made by hand atomizer from June 6 to August 1*— Gray (188) . One peroent of DDT in kaolin was dusted on sheets of paper on 'anion inseots were separately plaoed and covered with a beaker* This dust proved ineffective against aphids.— Sen (311 ) . Large aphid populations that existed in all alfalfa plots dusted witii 10 peroent of DDT in pyrophyllite were practically eliminated. Most of the ooamon alfalfa-field inseots observed in the DDT-treated plots probably were immigrants.— Li eb ©roan (245) . Ceroopidae Aphrophora saratogensis (Fitch), the Saratoga spittle bug At Milwaukee, Wis*, oil emulsions containing from 0*1 to 1 percent of DDT were tested* Sprayed pine trees showed no sign of tip kill at the end of the season* The material appeared to have a distinct repellent effect, but nhen the inseots were caged on sprayed branches complete mor- tality usually resulted in 24 hours*— Craighead and Brown (125 ) ♦ Unidentified spittle bugs A DDT aerosol produced exoellent kills of spittle bugs on peas.— Ditaan (135 )* Philaenus leuoophthalmus (L.), froghopper Greenhouse and inseotary tests t DDT, 4 ounces in peerder suspension per 100 imperial gallons of water, applied as a residual poison on foliage gave oomplete control of froghoppers* The same spray applied only to insects killed 98 percent; at 8 ounces 100 percent were killed* Tfihen used in a Velsiool emulsion 1 ounoe of DDT per 100 imperial gallons of water killed 88 percent of the insects and 4 ounces killed 94 percent* Gesarol A-5 dust applied to spittle had no apparent effect on nymphs.— Ross (306 ) * -62- Cicadellidae Aoeratagallla uhleri (Van D*), the western clover leafhopper la Nebraska 3-perc«nt DDT dust reduced the population to an in- aigaifioant 1 evel •— Tate et al. (342 ) ■ A 5-peroent DDT dust and a apray containing 4 pounda of 10-peroent DDT in pyrophyllite per 100 gallons of water greatly reduoed the numbers of adults and nymphs on potato plants in western Hebra ska. — Hill (209 ) • Dikraneura cooker ellii Gillette Sajse as for Brythraaeura variabilis * — Anon* (49), Vorhies and Wehrle (364 ) Bnpoasoa. abrupta DeL*, the western potato leafhopper In small field test8 a 3-peroent DDT dust, or a 1-peroent DDT dust with sulfur, reduoed the leafBopper-oymph population about 96 percent for at least 19 days. Dueti&g s3sX£e? alone reduoed the number of nymphs by about 50 percent*— J eppson and Borden (229) • aapoaaoa fabae (Barr*) , the potato leafaopper The potato leafhopper is controlled best by the higher (5 percent) concentration of DDT dust» The residues conapiououaly gave uore eatis- faotory kill of the young nymphs than the adult leafhoppers*— Granovaky At Beltaville, lid*, a great reduction in numbera of the potato leaf- hoppor on alfalfa and peanuta was obtained by two applicatiana 9 daya apart of a dust containing 2 percent of DDT in pyrophyllite, or of a apray conaiating of a mixture of 0*66 percent of DDT in duat form with water, with a 8preader added. Material increaae in yield and quality of hay waa obtained in the treated alfalfa plota* Two applioation8 16 daya apart of -the 8ame apray and duat to peanut8 resulted in great re- duotion of the leafhopper population but mo increase in yield because of severe leaf spot infection on both treated and untreated plots late in the season*— Paokard (285 ) • Although the knook-down of leafhoppers right after treataaat with DDT is less conspicuous than with pyrethrun, DDT gave better long-run results and almost complete oontrol of the leafhopper nymphs for a long time after eaoh application*-- Granovsky (186) * Potato leafhoppers were kept down by three applications of a 6- peroent DDT duat per season*— Granovsky (18 6 )* -53- A wettable powder containing 25 percent of DDT (4 pounds per 100 gallons of -water), applied at the rate of 125 gallons per acre, was more effeotive in controlling inseots and increasing yield than Bordeaux 8-12-100* The addition of 4 pounds of Fermate or Grass elli CAC still further eohanoed the yield.— Gui (192) ♦ Significant reductions an potatoes in Nebraska were obtained with a 3-peroent DDT dust and a 10-peroant DDT 8 pray 4 pounds per 100 gallons of water* In another experiment replicated plots of potatoes whioh were heavily infested with potato leafhoppers were treated three times with a 1 percent DDT dust at approximately 2-week intervals* Within 12 hours after the first treatment leafhopper populations were reduced to a relatively insignificant level and this oondition was maintained for 2 weeks even in the presenoe of frequent heavy rains. Foliage on the treat* ed plants remained green and the plants matured at the normal time, where- as foliage on the untreated plants was almost all dead 2 weeks earlier* An inorease in yield of approximately 265 peroent was obtained* Field plots of beans heavily infested with potato leafhoppers were treated on June 19 with 1 or 3 peroent DDT dusts. Nymphal population records were taken four times during the next 17 days. After 12 hours leafhopper nymphs were reduced to a very low and apparently insignificant level by both the 1 peroent and 3 percent dusts. Although the difference between the two dusts was not statistically significant, apparently the 3 per- cent dust was slightly better*— Tate et ^al* (342 ) » In small-plot experiments, 3-percent DDT dust gave good control of the nymphs and yielded 115 bushels of potatoes per acre, while 4-4-50 bordeaux plus 2 pounds of calcium arsenate yielded 98 bushels.— Apple (75). In a field test an beans 8 ounces of TOT per 100 imperial gallons of water gave complete control as a powder suspension and in Velsiool ♦Mulsion. Apparently newly hatched nymphs were killed as well as tha older nymphs and adults*— Ross (306) * At Jefferson, N* C*, plots treated with a 3-peroent DDT dust for the control of flea beetles and leafhoppers yielded more potatoes than did any of five other differently treated plots*— Kiilash (240 ) » Laboratory tests with a 3-peroent DDT dust gave 96 peroent oontrol in 3 hours*— Okla* Agr* Expt* Sta* (IT8 )* A 5-peroent DDT dust gave exoellent oontrol of the potato leafhopper on potatoes .—Hut son (220 ) • DDT furnishes one of the best examples of the need of proper spac- ing between plots when spraying or dusting and the influenoe of drift- ing materials on adjacent plots* The drift of small amounts of DDT into plots during applications and the carry-over of the same material on the -54- inside walls of spray equipment to contaminate the next-used formula, are sufficient to reduoe materially leafhopper populations and, thus, to increase the yields of sprayed potatoes. The drift effeot was distinguishable for a distance of about 8 feet on eaoh side of rows treated with DDT»— Wilson and Sleesman (577) • In a planting of early potatoes where the potato leafhopper became very abundant, four chemical treatments —DDT spray (Gesarol A-20) 4 pounds per 100 gallons of water (0,8 pounds of actual~"DDT) ; DDT dust (Gesarol A-3) 3 per cent j calcium arsenate 4 pounds, with fixed oopper (dompound A) 3 pounds per 100 gallons of water j and bordeaux mixture 5-4-50 -— gave results as follows: Leafhoppers per 16 leaves, 4, 5, 17, and 19; European corn borers per 10 potato stalks, 0, 2, 11, and 24; yields, bushels per aore, 179, 167, 146, and 116* The averages an the controls were 81 leafhoppers, 23 European corn borers, and 110 bushels per aore yield*— Wolfenbarger et al* (379 ) • Materials tested were 4-percent DDT dust containing 21 percent of Miorogel with a 30-70 copper-lime dust, and a Micro gel- calcium arsenate- talc (21-30-49) dust* Pour applications were made during the growing season at the rate of 30 pounds per aore-applioation (4 replications)* Yield of potatoes was 257 bushels on the TDT-Microgel plot as compared with 231 on the Miorogel-oalolum arsenate-talo plot* Excellent oontrol of this leafhopper was obtained. The control of potato flea beetles and Colorado potato beetle with the DDT dust was about equal to that of the calcium arsenate dust*— V* J* Agr* Expt. Sta. (275 ) * A wettable powder containing 25 percent DDT, 4 pounds per 100 gallons of water, applied at the rate of 200 gallons per acre at 10-day intervals killed all nymphs and increased the yield of potatoes more than any other treatment*— Sleesman (321) * In experiments conducted in southern Wisconsin a 2*5-peroent DDT dust reduced infestations of the potato leafhopper on potatoes and bean6 78 to 99 percent* These figures were obtained from counts of leafhopper nymphs 1 to 3 weeks after application. The DDT dust gave a greater re- duction in leafhopper populations than did a dust mixture containing 1 percent of dinitro-o-oyolohexylphenol and 50 percent of sulfur* In similar experiments in the Columbus, Ohio, area DDT sprays and DDT-sulfur dusts gave better results than did the dinitro mixture or a pyrethrum-sulfur mixture containing 0*025 peroent of pyrethrins and 50 peroent of sulfur. The DDT sprays contained up to 0*08 percent of DDT in a kerosene emulsion, and the dust mixtures consisted of 1*4 peroent of DDT, 60 peroent of sulfur, and the remainder pyrophyllite*-- *hite (373). -55- A knapsack sprayer was used in making five applications of 20 per- cent DDT spray on early potatoes and three applications on late potatoes. Potato leafhopper oounts with the different treatments varied consider- ably, but the population was definitely lower on the DDT plots than on the check.— Gould (184) » La the laboratory Gesarol A-3 dust killed 96 percent of the adult leafhoppers at the end of 3 hours*— Hamilton ( 200 ) « DDT at 0.75 pound per 100 gallons of water was not effective as a fungioide for early blight of potatoes, but controlled leafhoppers well. — -Heuberger (207 ) * A 3-percent DDT dust and a spray containing 1 pound of DDT in 100 gallons of water were tested against standard treatments. The DDT spray and the dust gave control of potato leafhopper on snap and lima beans superior to "that obtained with pyrethrum dust. Snap beans were stunted for a short period after they were treated with DDT.— N. J. Agr. Expt. Sta. (276). A dust containing 5 percent of DDT and copper applied twice at the rate of 20 pounds per acre per application gave the highest mortality of insects, including the potato leafhopper, of any material tested (arsenical, Dithane, DH dust plus copper, sabadilla plus copper, and copper-lime dust) •— Munro and Redman (270) • Bmpoasca maligna (Walsh), the apple leafhopper Apple nursery stock was dusted with a 5-percent DDT dust twice dur- ing the season at 1-^jonth intervals. The effectiveness of this treatment was compared with that of 4-4-50 bordeaux mixture applied 6 times between June 21 and August 12, 1944. The last three bordeaux sprays were mixed with 3/4 pint of nicotine sulfate per 100 gallons. Both treatments con- trolled the leafhoppers about equally well. Meotine sulfate took fair- ly good care of Aphis poroi Deg. in the bordeaux blook and the aphid popula- tion in the DDT block dldTnot increase. This shows that some of them were controlled with the DOT. Since the average annual growth in the DDT blook measured 17*23 inches, in the bordeaux block 15*55 inches, and in the oontrol blook 16*05 inches, it is evident that frequent bordeaux application reduces, whereas dusting with DDT slightly increases the annual growth of young apple nursery stock.— Granovsky (18 7)* Apple leafhoppers were controlled with a spray of 4 pounds of 20 percent DDT per 100 gallons of water.— Has eman (203 ) • DDT is very effective against apple leafhoppers.— Steiner et al. (334) . -56- DDT at 1 or 2 pounda per 100 gallons of water eliminated this species and also the rose leafhopper (Typhlooyba rosae (L*), both of which were rather abundant in an apple orohard in Hood River, Oreg*— Childs and Robinson (ill ) • Brythroneura oomes (Say), a grape leafhopper DDT-pyrophyllite (20-80) was used at the rate of 1 pound of DDT in 100 gallons of water plus 1/2 pound of soybean flour* The spray was compared with a lead arsenate-bordeaux mixture* Applications were made at the rate of 200 gallons per acre on July 16 and 27* The entire Tine- yard wes treated with the DDT spray on August 9* Most of the spray was directed toward the upper surface of the leaves to avoid spraying Hxm fruit* 3h the plot receiving three DDT sprays the infestation disappeared after the seoond application* In the plot receiving one spray of DDT following two lead arsenate-bordeaux sprays, the leafhopper infestation was under control for about 10 days* There was no injury from DDT sprays to foliage.— K. J* Agr* Expt* Sta. (275) * The grape leafhopper was controlled by 3 sprayings with 1 pound of DDT per 100 gallons of water* — Hutson (220 ) . Brythroneura elegantula Osb*, a grape leafhopper DDT was tested against this important pest of grapes in the San Joaquin Valley, Calif* In these trials, DDT applied either as a vapo-spray or as a dry dust mixed with sulfur appeared to be effective against adults and nymphs of the grape leafhopper* Toxicity to nymphs persisted at least 22 days* The effect of treatment was noticed 4 months after application* The vapo-sprays contained 0*6 or 1*2 peroent of DDT in a mixture of 10 percent light summer oil (60 viscosity) and 90 peroent of kerosene* The dusts contained 50 percent of sulfur, sufficient A-K 20 to make 1, 5, or 5 percent DDT, and the remainder Frianite.— Fraaier and Stafford (169 ) • Brythroneura variabilis Beamer A 5 percent DDT-oil fog made by feeding a DCT-oil solution into a current of steam proved effeotive in the Salt River Valley, Aril* First trial was on a 10-acre block of Bumstead grapes where leafhoppers averaged 70 to the vine* A pick-up truok, carrying a generator, ran along two sides of the block for 7 minutes* In that time 14 gallons of orohard spray oil containing 5 percent of DDT was turned into a fog that was carried over into the vines by a light breeze . The population ]£ days later was 1 leafhopper per vine* In the next few days 100 acres were "fogged," with the same result. The leafhoppers were wiped out*— Anon* (49) , Vorhies and Wehrle (364) • -67- Erythroneura spp., grape leafhoppers A spray of 1 pound of DDT per 100 gallons of water used against Po ol Ilia ^aponlca Newm. gave excellent control of leafhoppers on grapes. — Hadley and Fleming (196) • A 3-percmt DDT dust was effective against leafhoppers on grape.— Baseman (203) • Promising results in the oontrol of the grape leafhopper were obtained in preliminary tests in Ohio with 1.6 pounds of DDT (dissolved in a mix- ture of benzene and kerosene whioh was then emulsified) per 100 gallons, and in New Jersey with the same formula as used in tests against adults of the Japanese beetle.— Baker and Porter (81) • One application of DDT, 8 ounoes per 100 imperial gallons of water, on July 15 gave complete control of nymphs and prevented breeding for the remainder of the season* In a large-soale field test two applications of DDT, 16 ounces, at 10-day intervals, gave apparently 100 percent con- trol.— Ross (306) . Butettix tenellus (Bak.), the beet leafhopper In 11 replications of a field experiment with the beet leafhopper on sugar beets at Twin Falls, Idaho, 116 pounds per acre of a 5-percent DDT dust resulted in an average reduotion in populations of 95 percent after 3 days and 89 percent after 10 days. A spray containing 4 pounds of 10- percent DDT applied at 200 gallons per acre did not give so great a re- duction.— White (373 ). Macrosteles divisus (Uhl.), the six-spotted leafhopper A large carrot field was divided into plots with an area of 1.335 acres for each of six treatments, two of whioh contained DDT at 20 and 25 pounds per acre in three applications per season. DDT, 5 percent in pyrophyllite, and also 5 percent plus 5 percent of yellow copper oxide in pyrophyllite, gave very satisfactory results in controlling this in- sect, and a greater percentage of disease-free carrots as oompared with other plots.— Gran ovsky (185 , 186 , 187) . A 3-peroent DDT dust was oompared with a 1 percent rotenone-25 per- cent sulfur dust and an untreated check. Dusts were applied to a com- mercial planting of Big Boston lettuoe with a self-propelled 6-row power duster using two nozzles per row. Five applications were made at week- ly intervals, the first one when the leaves were about 1 inch in diameter. The dusts were applied at the rate of 25-30 pounds per acre. A rotenone- sulfur dust was substituted for the DDT at the fifth application. Leaf- hopper counts 3 days after the third application were as follows: DDT 0.20 -68- per plant; rotenone 0.09 per plant, check 3.36 per plant* Lettuce yellows counts at harvest were: DDT 8.3 percent, rotenone 4.4 percent, check 31.8 percent.— N. J. Agr. Expt» Sta. (275 ) . Typhlocyba pomari a McAtee, the white apple leafhopper The results of preliminary experiments indioate that DDT may effec- tively control some species of leafhoppers. At Yakima, Wash, and at Vinoennes, Ind», the DDT formulas used for control of the codling moth (1 pound DDT per 100 gallons of water) also appeared to control apple leafhoppers (chiefly Typhlocyba spp.).— Baker and Porter (81). Injury was practically absent from codling moth plots receiving DDT, but noticeable on adjacent lead arsenate-oil plots.— Ross (306 ) . Typhlocyba rosae (L.), the rose leafhopper See ISnpoasca maligna *— Chi Ids and Robinson (111) . Unidentified leafhoppers One application of a DDT aerosol caused 100 percent reduction of aster leafhoppers on lettuce.-- Ditman (133). The bean leafhopper was completely eliminated with one application of DDT. [Presumably a 3-percent dust] Apparently the DDT did not act as an ovicide.— Russell (308 ) . Cocoidae Aonidiella aurant ii (Mask*), the California red goal© The addition of 4 grams of DDT to 100 ml. of light medium spray oil increases tne effectiveness of the oil, based on counts made to ascertain the degree of infestation on trees 3 to 14 months after treatment. Only 2 out of 5 treatments applied during November, 1943, produced a marked improvement in red scale oontrol due to the addition of the DOT. However, in experiments made during the spring and summer months the DDT always in- creased the effectiveness of the oil. Three percent kerosene contain- ing 4 percent of DDT was never so effeotive as the 1 3/4 percent light medium or heavy medium spray oil with which it was compared, but in- creasing the amount of DDT in the kerosene by means of solvents or spraying twice a year with the 3 percent kerosene-DDT solution gave promising results and will warrant further investigation, especially since kerosene does not accentuate water spot of navel oranges as does regular oil spray. -59- Gesarol AK-20, e proprietary powder containing 20 percent of DDT, was • es a spr'ay (without any oil) at 10 pounds to 100 gallons of water, but even in double applications it was not so effective as 1 3/4 per- cent light-medium or heavy-medium oil spray. A 5-percent DDT dust, using li pounds per tree in two applications, one in July and one in August, resulted in no improved red scale control when compared with thfuntreated check plot. In the past year's field work, cube root added to kerosene-DDT spray decreased the longterm effectiveness of the spray 5 times in the 6 trials in which the comparison was made. This is a highly paradoxical situation since cube root increases many- fold the ability of kerosene to kill red scale. It cannot be argued in this instance ihat the insecticidal effect of the cube root against the relatively unimportant predators and parasites of the red seal® ouWghed its effect in increasing the initial kill of , the red scale, for the DDT appears to be even more effective against predators and parasites and this material was present in all the kerosene sprays.- Ebeling (142). The addition of IDT to oil sprays produced little or no immediate effect, but the residual value against the crawlers was considerable in cool weather as compared with that in hot weather.— Baker and Porter (81). The value of DDT for citrus insect oontrol is yet to be determine*. Although the material is promising for the control of citrus thrips and scale insects much more work on a large scale is needed.— Boyoe (95). Aspidlotu8 perniclo8U8 Comst., the San Jose soale A spray of 4 pounds of 20-peroent DDT per 100 gallons of water applied to apple trees did not oontrol this scale on the fruit.— Baseman (203 ). Chrysomphalus acnidum (L.), the Florida red soale No benefit appeared to result from the addition of DDT to oil sprays. —Baker and Porter (81). Chrysomphalus dictyospermi (Morg.), the dictyospermum soale An emulsion containing about 0.2 percent of DDT, applied four times within 5 months, proved highly effective against these scales on about 50 speoies of orchids. The emulsion was prepared by adding a solution of 20 parts by weight of TOT in 60 parts of xylene and 20 parts of Triton X-100 to water. Young scales or orawlers are unable to live on any por- tion of the plant that has been coated with the spray. All mature soales will not be killed by a single application but repetitions of the sprays at 3- or 4- week intervals should ultimately eliminate all scales, both young and old. Ho injury to the plants occurred.— Cory (119) • -eo- Coooua hesperldum L. # the soft scale Coocua psoudohesperidum (Ckll.) Diaspis bolsduvalil Sign. Same as for Chrysomphalus diotyospermi (Morg.) .— Cory (119 ) . Lepidosaphes floifoliae (Berlese), a fig scale Field tests with DDT residual spray to control crawlers were un- suooessful in all but one doubtful case where a talc powder containing 20 percent of DDT was applied at 4 pounds per 100 gallons of water plus 1/4 percent heavy-medium soluble oil on July 17. It is not known what control a 1-percent heavy-medium oil spray would give if it were applied along in July,— Stafford (327) • Lepidosaphes fious (Sign.), the fig scale Same as for Chrysomphalus aonldum .— Baker and Porter (81). Lepidosaphes tuber cu la tus (Sign.) Same as for Chrysomphalus dictyosperroi (Morg.) .--Cory (119 ) • Lepidosaphes ulni (L«), the oystershell soale DDT is not effeotive against the adult scales, but is effective against the orawlers or migrating young.— Annand (74). Par la tor ia chin ens is Marlatt i « ■ ■ i ■» i - . -m m The addition of DDT to oil sprays improved the immediate kill but had no residual effect on tne crawlers.— Baker and Porter (81) . Parlatoria oleae (Colvee), the olive scale Tests were conducted in the laboratory and in the field with a hand sprayer and a power-driven sprayer using a 20 percent DDT wet table powder and DDT dissolved in oils. In none of the tests conducted were the results satisfactory for commeroial practice. Control of olive soale always increased with viscosity and concentration of oil regardless of concentration of DDT. Even fresh deposits of DDT did not prevent many orawlers from settling and reaching the second instar. The use of DDT seems, therefore, to offer no solution to the problem of controlling olive scales that settle under their mothers 1 shells.— Stafford (327). -61- Parlatoria proteus Curt* Same as for Chrysomphalus dictyoaperni (Morg.) •— Cory (119) ♦ Pseudocooous citri (Risso), the citrus mealybug In one small-scale test in a greenhouse there was no appreciable kill from one application of a spray containing 24 ounces of DDT in powder form per 100 imperial gallons of -water.— Ross (506) . Pseudococcu8 comstocki (Kuw.), the Corns to ok mealybug In laboratory and orohard tests DDT at the rate of 1.5 pounds per 100 gallons has been found promising for control of this mealybug. Lab- oratory tests indioate that the spray affects the young mealybugs but not the mature females. The spray deposit is ooasiderably more toxio after a few hours than after 12 to 13 days.— Hough (217) . Results obtained with DDT on the newly hatched crawlers were promis- ing enough to warrant further tests.— Baker and Porter (81). Pseudooocous maritirous (Ehrh.), the grape mealybug Results with DDT on plants were unsatisfactory. Three weeks after spraying 70 percent of the plants showed infestation by Pseudoooocus maritirous , whereas plots sprayed with Loro were only 11 peroent infested. The DDT formula consisted of 10 pounds of 10 percent DDT in pyrophyllite (1 pound of DDT) in 100 gallons, with 3 fluid ounces of Du Pont spreader- sticker added. Applications were made with a power sprayer, 500- to 600- pounds pressure, with two large disc noazles.— Houser and Neiswander (219 ) Pseudoparlatoria perlatorioides (Comst.) Sai8setia hemisphaerica (Targ.), the hemispherical scale Same as for Chrysomphalus dlctyospermi (Morg.) .—Cory (119 ) • Saissetia oleae (Bern.), the black scale Two field tests were made against this pest on olives. An oil-DDT spray (2 gallons of a light medium soluble oil containing 5 peroent of DDT per 100 gallons of water) and an oil-derris spray (0.5 pound of derris containing 5 peroent of rotenone per gallon of heavy medium oil) gave about equal control of adult females, but apparently the crawlers were more efficiently controlled with DDT than with derris. Before recom- mendations are made for the use of DDT, further evidenoe of control should be obtained.— Stafford (327). -62- Psyllldae Paratriosa cockerelll (Sulc), the potato psyllid Gesarol A-3 dust gave better results than sulfur- calcium arsenate or sulfur-basic copper arsenate dusts in tests at Las Vegas, N« Mex.^ in 1944. —Eyer (147). In a large field test in Nebraska a 3-percent DDT dust and a spray of 4 pounds of 10 peroent DDT per 100 gallons of water were equally as effective as the sulfur compounds*— Tate et al. (342 ) . Five applications of a 3-percent DDT pyrophyllite dust applied at the rate of about 35 pounds per acre per application or five applications of a spray containing 4 pounds of 10-percent EOT in pyrophyllite per 100 gallons of water applied at the rate of about 125 gallons per aore per application greatly reduced the number of both adults and nymphs on po- tato plants in western Nebraska. DDT remained effective against potato psyllids under field conditions for a relatively long period of time»— Hill (209). One application of Gesarol A-3 dust gave an average control of 78.5 peroent in two tests.— Hibbs (208) . Psylla buxl (L.), the boxwood psyllid A dust containing 0.8 peroent of BDT (A-20 in sulfur) applied on adult boxwood psyllids in two insectary cage tests in July killed 62 and 69 percent of the insects in 38 hours and 81 and 97 percent in 50 hours. There was no revival noted at the end of 72 hours.— Underhill ( 349 ) . Psylla pyricola Foerst., the pear psylla In one orchard dormant miscible oil, containing DDT in solution, applied to give 5.12 ounces of DDT per 100 gallons, showed no advantage over the same oil containing no DDT in control of egg deposition or de- velopment of first-brood infestation. In test orchard No. 2, spraying was more timely, no egg laying having occurred prior to application. The DDT formulation reduoed egg laying and first-brood nymphs as compared with oil alone. There was no adverse effect on buds, bloom, foliage, yield, or fruit site or condition from DDT in this formulation.—Cleveland (1U). HEMIPTERA (Suborder Heteroptera) Anthocoridae Orius insidiosus (Say) -65- Orius triaticolor (nhite) DDT signifioantly reduoed the number of flower bugs on potatoes in western Nebraska*— Tate et al. ( 542) ■ DDT was applied as a 5-percent dust in pyrophyllite and as a spray containing 4 pounds of 10 percent DDT in pyrophyllite per 100 gallons of water in field tests in Nebraska during 1944* Populations of certain beneficial inseots, suoh as Orlus spp. were found to be significantly reduced by the DDT dust or Spray. The adverse ef feot of DDT on predatory species seems to be minimised by the fact that this material also con- trols the major potato pests found in this state. DDT had no injurious eff eot on potato plants at the strengths used.— Hill (209 ) • Cimicidae Cimex lectularius L., the bedbug A kerosene spray containing 5 percent of DDT is remarkably effec- tive against bedbugs. Mattresses, pillows, springs, and bedframes should be lightly sprayed so that the surface is barely moistened. The advan- tage of this treatment over fumigation is that reinfestations are elimi- nated for several months, whereas fumigation kills only the bugs present at the moment.— Freeborn (160) . A severe and long-standing infestation of bedbugs in the animal rooms of a biologioal res ear oh institution in Toronto was reported elimi- nated by dipping the cages in a 5-peroent solution of DDT in refined kero- sene, using benzene as an auxiliary solvent •-•Ross (306) . At the ninth annual Pest Control Operator's conference held at Purdue University January 16-19, 1945, the results of a demonstration of DDT on bedbugs were tabulated and a 100 percent kill observed.— Anon. (2, 15) • The le-ttial dose of pure DDT for Cimex was about 10 mg. per square centimeter.— Buxton (100) . A 20-percent IDT dust and 3 percent of DDT in kerosene spray gave excellent control.— N. J. Agr. Expt. Sta. (2 75 ) . DDT is a contact poison.— Domenjoz ( 13 5 ) . A bedbug exposed to filter paper bearing a deposit of DDT was found dead the next day.— Vargas et al. (360 ) . Kaolin containing 1 percent of DDT was dusted on sheets of paper on which the inseots were separately placed and covered with a beaker. The time to total paralysis was 340-380 minutes and to death 940-980 minutes. — Sen (311). -64- Coreidae Anasa tristis (Deg.), the squash bug Adults and nymphs were very effectively controlled in replicated plots established in heavily infested commercial plantings by 5 peroent of DOT alone and in combination with 6 peroent of yellow oopper oxide •— Granovsky ( 187 ) . A 3-percent DDT dust was effective up to about half-grown bugs; a 10-percent dust controlled adults but injured the plants.— Has em an (205 ) . Not controlled by a D 1 ^ aerosol.— Ditman (133) * In small field tests in California, only 12 adult squash bugs sur- vived 13 days after the last of two applications of a 10-percent DDT dust mixture. In comparable untreated plots the survivors included 221 adults, 20 eggs, and 7 nymphs .-^White (373) • In a small-soale test in a greenhouse 4 ounces of DDT in powder suspension per 100 imperial gallons of water was only moderately effec- tive, killing 55 percent of the nymphs within 4 days*— Ross ( 306 ) • A 3-peroent DDT dust that had no value as an ovioide killed 32 per- oent of the young nymphs in 2 days but oaused no knookdown of adults in cage tests*— Janes ( 22 6) . Laboratory tests with a 3-peroent dust gave 68 peroent control in 48 hours. Nymphs are more susoeptible than adults. — Okla. Agr. Expt. Sta. (278), This bug was kept completely under control when Gesarol A-3 dust was applied at 3- to 5-week intervals. This dust increased the growth of yellow summer crook neck, scallop or pattie pan, and zuohini squashes. —Parker (287) . A test was conducted in the field on mature squash plants already severely damaged by a heavy infestation of half-grown and older nymphs and adults; hence the number present was not known. Dasts containing 1, 2, and 3 percent of DDT and a sprey containing 1 pound of DDT in 100 gallons of water were applied. At the end of 24 hours both adults and nymphs were still active in all treatments. After 48 hours very few bugs were seen; careful examination 72 hours after the application show- ed large numbers killed by each treatment, but a few nymphs and adults survived each one, the largest number of each stage being in the cage reoeiving the spray*— Lyle (24 9) • Applications of 3-percent DDT dust to heavily infested squash plants caused nymphs of ali sites to emerge from under leaves. These nymphs -66- were than heaTily dusted. Observations at 24, 48, and 72 hours reveal- ed no dead bugs* This treatment was repeated four tines with similar results* Other areas were treated with a 20-percent DDT spray material, but no adults or nymphs were killed* The end of a vine was heavily dusted and 15 adults, 16 last-instar nymphs, and 25 young nymphs were placed on the vine in a cage. At the end of 48 hours only 1 newly emerged adult had died, while nymphs hatohing from an egg mass were aotive*— Gould (184 ). A 3-percent DDT dust and a spray containing 1 pound of DDT in 100 gallons of water were tested in preliminary small-plot field experiments on cucurbit crops* DDT spray and dust gave fair control of early-instar nymphs of the squash bug* DDT treatments caused severe plant injury to young acorn squash, cantaloups, and cucumbers. The yield of Hubbard squash was reduoed by application of DDT. — H. J* Agr* Expt. Sta* (275) • DDT applied as a dust, or as a spray, either in the form of a suspen- sion or an emulsion proved unsatisfactory against adult squash bugs* The zylane-Triton emulsion of DDT (20 parts DDT, 60 parts xylene, and 20 parts Triton X-100) caused marked terminal and marginal injury of squash plants for all concentrations of DDT above 1 per cent ♦— Ha vi land (204) • Leptocoris trlvtttatus (Say), the boxelder bug Spraying the sides of a heavily infested house with 1 pound of DDT (20 percent DDT-80 percent talc) in 100 gallons of water eliminated the pest for about 1 week*— H* J* Agr* Expt* Sta* (275 ) • Leptoglossus phyllopus (L*), the leaf -footed bug This bug occurs in thousands on oowpeas in Mississippi in late sum- mer. Tests were made in which cowpea plants were placed in screened cages, together with 25 adult insects* All the insects died within 4 days when both plant and bugs were dusted with 3 percent DDT, and 24 died within 9 days when the plant only was dusted or sprayed (l pound DDT in 100 gallons of water) with DDT* In other tests a 2 percent dust applied directly to the adults killed 70 percent in 24 hours and 85 per- cent in 48 hours*— Lyle (249) , Lygaeidae Blissus leucopterus ( Say) , the chinch bug Fifty chinch bugs were placed in a cage with a film of 3-peroent DDT dust on the bottom* After 2 hours the oust caused a mortality of 42 percent, after 4 hours 69 percent, after 5 hours 89 percent, and in 6 hours 100 peroent*— Hibba (208)* Li laboratory tests an the chlnoh bug the peroentage of mortality inoroased with the amount of DDT used* Adults were more susoeptible than nymphs* Under unusually heavy dust applications for field con- ditions, control was only 14*9 percent of the nymphs and 81*1 percent of the adults •--Hamilton (200). The results of laboratory and field tests seem to show that al- though DDT is toxic, the aotion is slow and not comparable to dinitro-o- cresol* A mortality of 100 percent was obtained 1 hour after colleot-*" ing adult and fifth-instar bugs that had walked through a 1 percent di- nitro-o-cresol dust barrier* Only a 33-percent mortality was obtained 24 hours after collecting bugs that had walked through a 6-peroent DDT oust barrier* A 10-peroent DDT dust applied direotly to adult chinoh bugs killed 90 percent in 24 hours*— Decker (131) * In field test 8 in Indiana barrier lines of dust containing 5 per- cent or more of DDT in pyrophylllte, applied at the rate of about 1 pound per rod, gave excellent protection of corn from immature chinch bugs migrating to it on foot from adjaoent wheat* The dust did not act as a repellent or prevent some of the bugs from reaching the oorn, but it killed "tii em before they were able to injure the corn materially. Heavy applications of dusts containing 1 to 5 percent of DDT in pyrophylllte directly to the infested portions of the corn plants and the surface of the soil close to them gave excellent control of the bugs without discernible injury to the plants*— Packard (285 ) * A 3-peroent DDT dust was ineffective.— Has eman (203). Laboratory tests gave good control only when 3-peroent dusts were applied heavily* Adults are more susceptible than nymphs.— Okla. Agr* Bxpt. Sta. (278)* Oncopeltus fasciatua (Dall.), the large milkweed bug Same as for Melanoplus f erour-rubrum .— AIF (66) • Mirldae Adelphooori8 lineolatus (Goese) See Lygus oblineatus *— Oranovsky (187 ) • Adelphooorls rapidus (Say), the rapid plant bug See Lygus oblineatus *— Granovaky (187 ) j Loft in (247 ) • -67- Adelphocoris superbus (Uhler) In tesxs on caged cotton plants, 2*5, 5, and 10 percent DDT gave excellent kill.— Loftin (247) « Calocoris norvegicus (Gmelin) In a field test on strawberries almost 100 percent control was se- cured with DDT in aoetone suspension with Tergltol Penetrant 7 at both 8 and 16 ounoes per 100 imperial gallons of water.— Ross (306) * Chlamydatus associatus (Uhl.) Same as for Aceratagallia uhleri (Van D*) •—Tate &t jil* (342) • A 3-peroent DDT dust and a DDT spray (4 pounds of 10 percent DDT in pyrophyllite per 100 gallons of water) greatly reduced -the numbers of adults and nymphs on potato plants in western Nebraska*— Hill (209) • Creontiades femoral! s Van Dutee See Adelphocoris superbus >— Loftin (247) • See Chloroohroa sayi ,— Phthirus pubis (L*), the crab louse DDT is a contact poison.— Domenjot (135) • COLEOPTBRA Anobiidae Lasio derma serricorne (F»), the cigarette beetle See Bphestia elutolla *— ^flhite (373 ) • Bostrichida® Rhizopertha dominioa (F*), *h® lesser grain borer The addition of 0*005 peroent of teohnical DDT to seed wheat (12- peroent moisture content) killed all introduced adults at the end of the first week* In another test the addition of suffioient 3 peroent DDT- pyrophyllite dust to give a concentration of 16 p*p»m* of DDT in the wheat caused 100 percent mortality in 1 week*— Cotton et al* (120 )* Bruohidae Bruohus braohlalis Fahraeus, the vetch bruohid DDT is the only oontrol yet found effective.— Burtner (98) . -78- Qn hairy vetoh in Oregon two applications of a 6-percent DDT dust at rates of 22 to 25 pounds of the dust per acre as the pods began to set and 15 days later gave excellent control of the vetoh bruohid with- out risible injury to tiie plants, and were eignifioantly better than two applications of a dust containing 1 peroent of rotenone at approximate- ly the same rates per acre.— Packard (28 5) * Bruchus plsorum (L«), the pea weeril In laboratory experiments at Moscow, Idaho, in 1943, relatively low mortalities of the pea weevil were obtained with a 10-«peroent DDT dust when the weevils were transferred from treated cages to clean cages 5 minutes after treatment* Later tests showed that the mortality could be increased by retaining the insects in the treated cages for a longer time* In 1944 field experiments were oonduoted on plots 24 feet wide and located end to end around the edges of large fields of peas grown for seed* In 21 replicates a 5-peroent DDF dust reduoed the adult pea weevil infestation 99 peroent in 2 days, whereas a 0*75-peroent rotenone dust reduced the infestation 98 peroent in a like period* In these tests the insecticides were applied with a power duster at the rate of 30 pounds of the DDT dust mixture and 20 pounds of the rotenone dust mixture per acre* In 7 replioates 2*0 peroent of the dried peas in the DDT plots were weevily as compared with 2*7 peroent in plots where rotenone dust was used*— *!hite (375- )* The pea weevil was controlled by eight applications of 5-percent DDT in light summer cpray oil, average about l/2 gallon per aore, with a hand atomiier from June 6 to August 1*— Gray (188 ) * Byturidae Byturus tomentosus F*, the raspberry fruitworm In England a laboratory preparation of DDT (75 peroent p-p f compound) oontaining 0*05 percent of Agral 2 and 0*025 peroent of sulfite-lye, and two proprietary preparations were tested* The proprietary preparations were not exactly alike* In 1945 a product of Swiss origin was used* This contained 5 peroent of 3DT on a base consisting of chalk and bentanite, together with a wetter of the Hekal type (an alkyl naphthalene sulfonate) • It settled out from suspension so rapidly that its use in this trial was possible only beoause of the very efficient agitation available in the spraying machine* In 1944 a British product was used which also oontained 5 peroent of DDT (77 percent p-p» oompound). However, the DDT in this product was on a base of china clay with some bentonite, together with alkyl naphthalene sulfonate and a dinaphthylm ethane sulfonate as auxiliaries* DDT at 0*025 peroent or at 0*05 pereent gave as good oontrol as a Lonohooarpus spray oontaining approximately 0*011 peroent of rotenone. -79- Although the difference between treated and control plots was highly significant, there was no significant difference in the results ob- tained with either concentration* In 1945 a single spraying with eaoh one of the materials was only moderately effective against a fairly heavy infestation, whereas in 1944 double spraying gave ex- cellent control of a lighter infestation irrespective of the spray used* In no case was there any evidence of phytotoxieity* The proprietary material^, which formed a better suspension, left a deposit on the fruit that made the earliest pickings unsalable*— Shaw (313 ) » Cerambyoidae Aoanthoolnus spp», wood borers Monoohaarus spp*, wood borers Preliminary work with TOT at Beltsville, Md*, Saucier, Miss., and Berkeley, Calif*, indicates that it may be an effective insecticide for use on valuable logs to prevent the attack of bark beetles, ambrosia beetles, and wood borers* Protection lasting 2 months was obtained with 2- to 10-percent solutions in Diesel oil or kerosene* Wood borers such as Monoohamu s and Acanthooinus were more easily killed or repelled than bark beetles, and particularly ambrosia beetles* The latter require concentrations of at least 5 percent* The tests in Mississippi were less effective than those at Beltsville, the great difference in rainfall probably being an important factor*— Craighead and Brown (125 ) • Megacyllene robiniae (Forst*), the locust borer Adults were killed when DDT was applied as an emulsion either to the goldenrod on whioh the beetles feed or to the stems of looust trees prior to oviposition.— Craighead and Brown (125 ) • Chrysomelidae Cerotoma trlfuroata (Forst*), the bean leaf beetle Controlled on green and yellow string beans with one application of Gesarol A-3 dust.— Parker (287 )* In a small patoh of beans grown in a victory garden this beetle was controlled by 5 percent of DDT in pyrophyllite*— Granovsky (187 )* Chaetocnema pulicaria Mel eh., the corn flea beetle Good protection of young sweet corn from the corn flea beetle and considerable reduction in the bacterial wilt which it transmits were ob- tained in experimental plots of a wilt-susceptible and a wilt-resistant variety at Beltsville, lid. Following 5 applications of 0*66 percent DDT -80- spray, obtained by adding 10 peroent DDT dust to -water containing a small percentage of spreader, at Intervals of 3 to 6 days, only 2 beetles were found on a treated row of corn as oompared with 128 on an untreat- ed row* In the susceptible variety a muoh better stand was maintained in the treated rows than in the untreated rows*— Packard (285) • Crioceris asparagl (L.), the common asparagus beetle C. duodecimpunotata (L«), the spotted asparagus beetle In greenhouse experiments from 16 to 32 times as muoh DDT was re- quired to kill adults of the spotted asparagus beetle as the common asparagus beetle. This difference seemed to hold for both stomach and contaot sprays* The stomach-poison sprays were made with DDT-talc-Orvus and were applied to the plant only, whereas the contaot sprays were made with DDT, Triton X 100 and Velsicol AR-60, and were appMed to the beetles only.— Ross (306) • Diabrotioa duodeelnpunctata (F.), the spotted cucumber beetle Both 3-peroent DDT dust and 35-percent cryolite dust gave equally satisfactory control of cucumber beetles. Young squash plants and pump- kin plants were severely stunted by EOT, the acorn squash being most susceptible. Young cucumber plants were stunted to some extent.— Tate et al. (342). A 3-peroent DDT dust was effective.— Has eman (203 ) . In greenhouse tests DDT applied as a stomach poison, 4 ounoes in powder suspension per 100 imperial gallons of water, gave exoellent con- trol of adults.— Ross (306 ) ♦ Indications are that DDT may be effective against the 12-spotted cucumber beetle.— Burtner (98, 99). Same as for Anasa tristis .— Granovsky (187 ) . During the second week of growth 30 hills of early cucumbers re- ceived 7 applications of 3-percent DDT dust. Cucumber beetles were kept under control, but some injury was caused to the plants. The margins of older leaves turned yellow and remained that way all summer. Harvest on these plants was delayed somewhat as compared with the remainder of the patch which was treated with cryolite. An infestation of lioe de- veloped on the DDT-treated plants first. After 6 applications of cryo- lite, 60 hills of late cucumbers (about 12 inches high) were divided in- to 2 plots, 1 receiving 3-percent DDT dust and the other 20-percent Gesarol spray. A total of 5 applications was made. Vo injury occurred -81- on the sprayed plots and yellowing was only faintly notioeable on the dieted plots* Melon lice started on these plants before harvest and hardly a oueunber was picked. The beetles were not troublesome. Two early treatments of cryolite and five applications of either 3-peroent DOT dust or 20-peroent Gesarol spray on 80 hills of cantaloups caused no vine injury and no beetle trouble. An infestation of melon lioe de- veloped on these plants* On 15 hills of squash the 3-percent dust caused rather severe yellowing of the foliage. No trouble from beetles, but a severe louse infestation developed on all plots.-- Gould (184 ). A. 3-peroent DDT dust and a spray containing 1 pound of DDT in 100 gallons of water were tested in preliminary small-plot field experi- ments on cuourbit crops. The DDT spray and dust gave outstanding con- trol of striped and 12-spotted cucumber b*"*tles, fair control of early- instar nymphs of squash bug, and control ec sparable to 1-peroent rote- none dust on squash borer. They were both inferior to a It 800 nicotine- soap spray against melon aphid. DDT treatments caused severe plant in- jury to young acorn squash, cantaloups, and cucumbers, and the yield of Hubbard squash was reduced.— N. J« Agr. Hxpt. Sta. (276) . Diabrotioa 11-punotata Mann., the 11-spotted beetle In laboratory tests adult beetles were very sensitive to DDT in any form. In most cases, the time required for a 100 percent kill was the same whether the insects were directly treated or were plaoed on treat- ed foliage. The beetles reacted to DDT within an hour, but several days were usually required for a final kill* There was no consistent difference between the percentages of DDT in -the oils for the range 0*3 to 5*6 per- cent. The 3~percent dust was superior to the 1-peroent dust*— Lange (242) * Controlled by eight applications of 6-peroent DOT in light summer spray oil, average about 1/2 gallon per acre, made by hand atomiser from June 6 to August 1.— Gray (188) * A 3-percent DDT dust and atomised oil containing 5 percent of DDT were effective. A bait spray containing 1 percent of DDT and 10 percent of brown sugar waB more effective than one containing 10 percent of barium fluosilicate and the same amount of brown sugar.— Gray and Schuh (189 )* Pour specimens swept from alfalfa were lightly dusted with 3-percent DDT dust (A-3) and held in an inseot net wiih alfalfa cuttings over night; all were killed.— Smith (324) ♦ Diabrotioa longicornis (Say) , the corn rootwora A 3-percent DDT dust was effective against the adults*— Hasemm (203 ). Diabrotioa vittata (P*), the striped cucumber beetle This beetle was completely controlled with Gesarol £-3 dust* The vines produoed until late summer, an unheard-of condition previously*— Parker (287). UBRARY .to pi.aNT BOARD -82- The cucumber beetle was susoeptible to DDT (Gesarol A-20) under laboratory conditions. The DDT was added to water at the rate of 0,8 pound in 100 gallons*— Fluke and Pond (157 ) > Same as for jtaasa tr i 6 1 i $ .— Or anovsky (187) • Sane as for Diabrotioa du o decimpunotata. — Tate et al. (542); Haseman (203)l Gould (184); N. J* Agr. Expt. Sta. (276). In greenhouse tests powder suspensions as a stomach poison gave 100 percent kill at DDT 4 ounces and over 75 peroent kill at 1 ounce per 100 imperial gallons of water.— Ross (506) • Epitrlx oucumeris (Harr*), the potato flea beetle At Jefferson, N* C*, plots treated with a 5-percent DDT dust yield- ed more potatoes than did any of five other differently treated plots, but the tuber yield in the 1-peroent DDT dust plot was "the lowest* Ho injury to potato foliage was observed* The seasonal average of flea beetle holes of leaf surface was lowest in the 5-percent and highest in the 1- percent DDT dust Dlots*— Kulash (240) * Extensive tests made by the Oregon Agricultural Experiment Station are conclusive enough to warrant recomnendation of DDT for oontrol of the potato flea beetle*— Burtner (98)* A DDT spray (A-20), used at the rate of 2 pounds to 50 gallons of water, reduced feeding soars about as well as calcium arsenate and oryo- lite when used at the same dosage, but was not so good as a 2-4-6-50 oal- oium arsenate-bordeaux spray* However, the DDT-sprayed plots produoed as high a yield as did those sprayed with the bordeaux*— Anderson (75) • Same as Macro siphum solanifolii (Ashm*).— N* J* Agr* Expt* Sta* (275 ) DDT is being recommended for its control in Oregon*— Childs (110 , p. 68)* DDT was released in June 1945 for the control of the potato flea beetle in Oregon*— Jenkins (227 ) • A DDT aerosol produoed exoellent kills*— Ditaan ( 155) » The pest is effectively controlled by a concentration as low as 1 peroent of DDT, especially when -the dust actually hits the inseots. Within 24 hours a nearly oomplete mortality is obtained*— Granovsky (185 , 186 , 187). -83- A knapsack sprayer was used in making 5 applications of 20-percent DDT spray on early potatoes and 3 applications on late potatoes* Po- tato leafhopper counts on the treated plants varied considerably, but the population was definitely lower on DDT plots than on the check* Potato flea beetles, Colorado potato beetles, blister beetles, and tarn- ished plant bugs were not serious*-- Gould (184) * Pour pounds of a wettable powder containing 25 percent of DDT per 100 gallons of water, applied at the rate of 125 gallons per acre, was more effective than bordeaux (8-12-100) in reducing flea beetles and the number of liieir feeding holes*-- Gui (192 ). Although DDT was responsible for an average reduction of about 80 percent in flea beetle feeding, there was no apparent effect on the num- ber of flea beetles on the plots adjacent to those treated with DDT.— Wilson and Sleesman (377 )* Although a 3-percent DDT dust was not so effective as a 2-5-6-50 calcium ar6enate-bordeaux spray in keeping flea beetles from feeding on potato foliage, bordeaux- DDT merits further testing .--Walker (365) • Epitrix fuscula Crotch, the eggplant flea beetle This insect was controlled when Gesarol A-3 dust was applied at 3- to 5-week intervals to eggplants •— Parker (287) * Six applications of 3-percent DDT dust made between June 14 and July 28 gavo very effective oontrolj "the dust was slightly superior to 35 percent cryolite.— Tate _et al. (342 ) • Same as for E. cu cum er i s .— Gui (192) . Epitrix hirtipennis (Melsh.), the tobacco flea beetle In a field experiment at Oxford, N. C, a 6-peroent DDT dust gave 66 percent oontrol based on a comparison of the number of beetles sur- viving on treated and untreated plots following the first application, and 59 percent following -the second application. Three 60-percent cryolite dusts, each in a different diluent, gave control ranging from 39 to 54 percent.— *hite (373 ) . Same as f or B. fuscula .— Tate et al. (342). E. parvula (F.) Same as for E. cu cum er 1 s . —Gui (192). -84- E. 8ubcrinlta (Leo.), the western potato flea beetle Same as for E. tub erls >— White (573 ) . Epltrix tuberls Gentner, the tuber flea beetle DDT dust was placed in soil around potato plants at a depth of about 2 inches for controlling tuber flea beetles* Harked reductions in larval injury to tubers was obtained with both a 3-peroent and a 10- percent dust applied at the rate of 200 pounds per acre. Some control was indicated by applications of 100 pounds per acre, but no improvement was shown by 50-pound applications* In the laboratory a 3-peroent DDT dust gave 81 percent mortality of adult beetles as oompared with 41 per- cent with cryolite-sulfur dust, which is the dust now being used for flea beetle oontrol in western Nebraska.— »Tate et al. (342) • A 3-peroent TOT dust is recommended in Oregon for the control of this beetle on potatoes. Atomized oil containing 5 percent of DDT is also effective. — Gray and Schuh (189 ) • Experiments comparing cryolite, calcium arsenate, and DDT dust mixtures against the tuber flea beetle and the western potato flea beetle were conducted in the Yakima Valley, Wash. The tuber flea beetle, form- erly designated as the western form of E. cucumeris (Earr.), was the predominant species. Four applicati an s~bf~a~TC— percent DDT dust at the rate of 17 pounds compared with a 70-percent cryolite dust mixture applied at 10 pounds per acre-application yielded the following results: DDT plots 42 percent damaged tubers; cryolite plots 54 percent damaged tubers. The total yield of marketable potatoes was about the same for both treat- ments.— ^Ifhite (373 ) . Epitrix spp. Same as for Bruohus pis orun . —Gray (186) • A 3-peroent DDT dust was effective against flea beetles an eggplant. — Haseman (203 ) . Eggplants in late August had a heavy population of flea beetles. One treatment of 20-percent DDT spray applied with a knapsack sprayer appeared to have no effect on the population, as observations 24 and 48 hours later revealed the beetles still feeding on the residue-covered plants.— Gould (184 ) • Fidla viticida Walsh, the grape rootworn In preliminary tests with DDT favorable results were obtained in the control of this insect. --Baker and Porter (81) . -85- Leptlnotarsa decemlineata (Say), the Colorado potato beetle In a small-scale test 100 percent mortality resulted when late- instar larvae were lightly and evenly coated with Gesarol A-3 dust (3 percent DDT), and no feeding was done after the dust was applied. In other laboratory tests potato foliage was treated in a bell-jar settling chamber and adult potato beetles were added. The treated foliage was changed dully. Mortality after 96 hours was 36 percent for Neocid No. 10 dust, 34 percent for Gesarol A-3 dust, and zero for the check. In a field test on lightly infested potatoes one application of Gesarol A-3 dust left «n average of 42 living larvae per 46 plants 1 week after application whereas a bordeaux-calcium ars«iate spray left an average of 3 larvae per plant.— Ross (306 ). A 3-percent DDT dust was effective.— Ha seman (203 ) ♦ In the laboratory a 2-percent DDT aqueous spray killed 74 percent of adults and larvae in 24 hours.— Hamilton (200). Laboratory tests with a 3-percent oust gave 74 percent: oontrol in 24 hour6»— Okla. Agr. Expt. Sta. (278) . Thia insect was controlled when Gesarol A-3 dust was applied at 3- to 5-week intervals to potatoes.— Parker (287) . A 3-percent DOT dust was very effective in controlling larvae and adults, and a 1-percent dust, although less effective, was superior to other materials. Gesarol Oil Spray SH-5 applied at the rate of 1:200 was ineffective. No injury to potato foliage was observed.— Kulash (240 ) . The tops of tj^oato seedlings were dipped in suspensions containing 1 pound of UDT and 4 pounds of lead arsenate per 100 gallons. In one series of tests 1 pound of sovbean flour and in another "Orthol K" medium summer oil emulsion (1/4 percaot actual oil) per 100 gallons were used as a sticker. Both treatments were equal in preventing feeding by the potato flea beetle and the Colorado potato beetle. The DDT-soybean flour treatment caused moderate yellowing and stunting of plants, whereas the DDT-oil treatment caused severe yellowing and stunting. The growth of DDT-treated plants was retarded 10 to 14 days when compared with lead arsenate-treated plants and untreated check plants. The DDT-treated plots yielded 19 tons per acre whereas the calcium arsenate plots yield- ed 22 tons.— N. J. Agr. Expt. Sta. (275). -86- A dust containing 5 peroent of DDT and copper applied twice at the rate of 20 pounds per acre-application gave the highest yield of potatoes and caused the highest mortality of insects, inoluding the Colorado po- tato beetle, of any material tested (arsenical, Dithane, DN dust plus copper, sabadilla plus oopper, and copper-lime dust) •— liunro and Redman (270). A knapsack sprayer was used to apply a 20-percent DDT spray five times on early potatoes and three times on late potatoes* Potato leaf- hopper counts varied considerably, but the population was definitely lower on the DDT-treated plots than on the check* Potato fleabeetles, Colorado potato beetles, blister beetles, and tarnished plant bugs were not serious •— Gould ( 184 ) * In laboratory tests DDT spray killed adults and young larvae after 24 to 36 hours* The DDT (Gesarol A-20) was added to water at the rate of 0.8 pound in 100 gallons*— Fluke and Pond (157 ) » Gesarol A-S dust gave complete oontrol of adults and larvae*— Fletcher (155). This pest was killed with remarkable ease in the adult and larval stages within 24 or 36 hours after dusting with a 5-percent DDT dust. From 2 years of experiments, it is evident that while DDT has a consider- able residual value on foliage under field conditions, it does not possess very long residual properties outdoors as compared with indoors* The combination of DDT with 5 peroent of yellow oopper oxide gave some- what better oontrol of most of the potato insects than the same concen- trations of DDT alone.— Granovsky (187) * A DDT aerosol produced excellent kills*— Ditman (133 ) • Pari a canella (F.) , -the strawberry rootworn In greenhouse tests, 8 ounces of 1SDT per 100 imperial gallons of water gave 100 peroent kill of adults both by stomaoh poisoning and by contact.— Ross (306 ) ♦ In the laboratory a water suspension of 4 pounds of 20-percent DDT powder with wetting agent (A-20) per 100 gallons of water was poured on a glass plate and allowed to dry* A white film was visible on the plate when the spray dried* After 291 days strawberry rootwonas were oaged with the plates and clean strawberry leaves* After 4 days all the insects were on their backs; after 5 days, all were dead* In a similar test a 3-percent dust (A-3) was also applied as a thin deposit on a glass plate, and insects were caged immediately with the plate and clean strawberry leaves. All the insects were dead at the end of '5 days, the speed of killing being no greater than that of the aged spray deposit described above*— Smith (325)* -87- Phyllotreta spp. Controlled by eight applications of 5-percent DDT in light summer spray oil, average about 1/2 gallon per acre, made with hand atomizer from June 6 to August 1*— Gray (188) • Adults were placed on foliage which had been treated in a bell jar settling chamber* The treated foliage was changed daily. Mortality after 48 hours was 99 percent for Gesarol A-3 dust, 91 percent for Neo- cid A-10, and 16 percent for the check*— Ross (306) • One application of Gesarol A-3 dust to turnips removed an infesta- tion of striped flea beetle in 2 days.— Janes (225 ) ♦ Cocoinellidae Adalia bipunctata (L*), the two-spotted lady beetle Under laboratory conditions adults are quite readily killed by walk- ing over surfaces sprayed with a water suspension of 13DT. The DDT (Gesarol A-20) was added to water at the rate of 0.8 pound in 100 gallons of water* —Fluke and Pond (157)* Epilachna varivestis Iftils*, the Mexican bean beetle Not controlled by a DDT aerosol*— Ditman (133) • In cage tests in New Mexioo a pyrophyllite dust containing 3 percent of DDT killed 93*8 percent of the larvae in 72 hours* In field tests this dust gave results as favorable as those of a 0*5 percent rotenone-talo dust*— Eyer (147) • Four applications of 3-percent DDT dust with sulfur added were made with a hand duster to bean plants infested with a few Mexican bean beetles and many potato leafhoppers* Dry weather eliminated the Mexioan bean beetle population and reduoed the yield from the plots* The yield varied considerably and that of the DDT-treated plots was below that of the un- treated area* The DDT dust had no harmful effect on the plants* — Gould (184). A 3-percent DDT dust and a spray containing 1 pound of DDT in 100 gallons of water were tested against standard treatments. The DDT treat- ments were inferior to a .4-percent rotenone dust in the control of the Mexican bean beetle.— N. J. Agr. Expt. Sta. (275 ). As in 1943, experiments in 1944 showed that DDT applied as a dust or as a spray suspension had little toxio effect on the Mexican bean beetle. In field experiments oonducted in North Carolina, the control from a 10-percent DDT dust, applied with hand dusters in two of the ex- -88- periments and with a power duster in another ranged from 41 to 49 per- cent; a duet containing 0.5 peroent of rotenone gave from 96 to 100 peroent oontrol. In field experiments at Columbus, Ohio, spray suspen- sions containing as high as 100 pounds of the 10-peroent DDT dust per 100 gallons of water did not control the Mexioan bean beetle.- Wh ite (373). Stethorus punotum (Leo.) Entirely absent from codling moth plots receiving DDT but common on adjacent plots treated with lead arsenate and oil*— Ross (506 ) » Unidentified Cocoinellldae No ooooinelid or ohrysopid eggs were observed on the fruit or foliage of a Bartlett pear orchard in the Sacramento River area, California, whioh has been sprayed with DDT •—Borden and Jeppson (91) • DDT significantly reduoed the number of lady beetles on potatoes in western Nebraska*— Tate e£ al. (542) • A pyrophyllite dust containing 10 peroent of DDT reduoed the popu- lation of ladybirds on alfalfa.— Lieberman (246 ). Oryzaephllus surinamensls (L.), the saw-toothed grain beetle In preliminary tests with DDT in California saw-toothed beetles in stored raisins were controlled.— Baker and Porter (81) • The addition of 60 p.p.m. of DDT to seed wheat (12-peroent moisture oontent) killed all introduced adults at the end of 1 week. The addition of sufficient 3-peroent DDT dust to give a oanoeutration of 16 p.p.m. of DDT killed all adults after 2 weeks.— Cotton at al. (120 ) • Cuoujida© Laemophloeus ferruginous (Staph.), the ruat-red grain beetle Almioide dust containing 2.6 peroent of DDT when mixed with wheat 1:40,000 killed 100 peroent of these beetles within 6 days.— Ross (506 ). DDT combined with an inert mineral dust and mixed with wheat was completely effective against rust-red grain beetles in mixtures as low as 1 part of the dust in 40,000 parts of wheat.— Smallman (522) . Curoulionidae Anthonomus eu genii Cano, the pepper weevil In a field experiment at San Clemente, Calif*, against the pepper weevil on bell peppers, DDT dusts at 10, 5, and 2.5 percent yielded high- -89- er mortalities than did a 70-percent cryolite mixture. The mixtures were applied with rotary hand dusters at 7-day intervals, at rates of 15 to 25 pounds per acre. In another experiment in which the 10- and 5-porcent strengths of IDT were applied at 14-day intervals the kill of weevils was greater than when the cryolite mixture was applied at 7-day intervals*— White (373) . Anthonoiaus grandis Boh., the boll weevil In cage and plot tests DDT dust was not so effective as calcium arsenate. In tests on caged plants the percent mortalities at Tallulah, La», were 75 from 10-peroent DDT and 84 from calcium arsenate, and at Waco, Tex., 16 from 10-percent DDT (16 pounds per acre), and 78 from cal- oium arsenate (8 pounds per acre) • In plots at Tallulah five applica- tions of 5-percent DDT dust failed to reduce the weevil infestation be- low that of the checks. In another experiment the addition of 2.5 per- cent DDT to calcium arsenate did not increase the effectiveness or pro- duce so much cotton as the calcium arsenate treatment. In other field tests in which DDT in pyrophyllite or mixtures of pyrophyllite and sul- fur were used for other insects, the boll weevil infestation was extreme- ly low but was not appreciably reduced by the DDT.— Loftin (247 ) . Anthonomus signatus Say, the strawberry weevil Gesarol A-3 dust (3 percent DDT) gave promising results in the pre- vention of bud cutting by this weevil and appeared to be more effective than a gypsum-cryolite (70-30) dust. The Gesarol was not available in time to apply it before bud cutting was well under way, so its full possibilities were not determined.— Ttoss (306 ) . Ceutorhynchus assimills (Payk.), the cabbage seedpod weevil In laboratory tests at Sumner, Wash., 10-percent 13DT dust showed no toxicity to the cabbage seedpod weevil. A bait spray containing 6 pounds of the 10 percent DDT-pyrophyllite mixture and 45 pounds of sugar in 100 gallons of water was also ineffective •«TOiite (373) • Conotrachelus nenuphar (Hbst.), the plum oaroulio DDT appears muoh less effective than lead arsenate. Tests at Belts- ville, Md«, with DDT-pyrophyllite (1:1), applied with various fungicides at the rate of 1 1/2 pounds of DDT per 100 gallons, indicated little con- trol of curculio on apple and peach. At Fort Valley, Ga., 4 pounds of DDT (with wetting agent) per 100 gallons seemed to be about equal to the standard 2 pounds of lead arsenate for control of this pest on peach.— Baker and Porter (81). Gesarol AK-20 at 2 pounds per 100 gallons was inferior to lead arse- nate at 3 pounds per 100 gallons in tests in New Hampshire apple orchards during 1944.— Conklin (116). -90- Ten peach trees were sprayed three times with 2 pounds of 20 per- cent DDT in 100 gallons of water to control the plum curculio. Owing to the low temperature of March 30 these trees held very little fruit, and comparable records of curculio infestation were not possible. There was no burning of foliage.— Fletcher (155 ) . DDT, 1 pound per 100 imperial gallons of water, was less effective than 5 pounds of acid lead arsenate, both used with either wettable sul- fur or oopper oxychloride.— Ross (306 ) • DDT failed to control curculio.— N. J. Agr. Expt. Sta. ( 275 ). Three applications of a spray containing 2 pounds of A-20 per 100 gallons of water caused no damage to foliage of peaches and no reduction in injury by curculio,— Dnderhill (349 ) . Peaches sprayed with 4 pounds of a wettable powder containing 25 percent of UDT yielded 49.6 larvae per 100 drop fruits. In the same ex- periment identical applications of standard lead arsenate, 2 pounds to 100 gallons, averaged 32.3 larvae per 100 fruits.— Neiswander (274). Curculio caryae (Horn), the pecan weevil Curculio rectus (Say), the chestnut weevil In preliminarv tests DDT gave favorable results.— Baker and Porter (81). C ylas fortaicariu8 elegantulus (Summers), the swoetpotato weevil In laboratory tests at Opelousas, La., DDT was toxic to the sweet- potato weevil but not so toxic as potassium fluosilioate. The 10-peroent DDT gave mortalities ranging from 82 to 98 peroent, as compared with 98 to 100 percent with undiluted potassium fluosilicate and 80 peroent with undiluted oalcium arsenate.— White ( 373 ) . Cylindr q c opturus eatoni Buchanan, the reproduction weevil A 1-percent DDT emulsion was effective in Calif ornia.— Craighead and Brown (125 ) * Listroderes obllquus Klug, the vegetable weevil In laboratory tests vapo-sprays and a 3-percent DDT dust were applied directly to the larvae or to l/4-inch carrot sections on which the larvae were later placed. The vapo-sprays containing 1.2 or 2.4 percent of DDT required 3 days to cause 100 percent mortality. The dusts containing 1 percent of DDT killed all weevils in 6 to 9 days.— Lange ( 242 ) . -91- Pantomorus godmani (Crotch), the Fuller rose beetle Same as for Paria can el la .—Smith (525 ) • Pantomorus leucoloma (Boh.), white fringed beetle Then used as a stomach poison, DDT in dust form was 69 to 74 times as toxio as sodium f luoaluminate, and a spray containing 1/8 pound of DDT per 100 gallons of water was about as effective as a spray contain- ing 8 pounds of synthetic cryolite (85.4 percent sodium fluoaluminate)© The quantity of DDT applied per acre is the important factor affecting mortality and not the percentage of H)T contained in the dust. As a contact poison dilute sprays containing 1/8 pound or more of DDT per 100 gallons applied directly to beetles produced net mortalities in ex- oess of 60 percent. Adults can accumulate a lethal dose of DDT from contact with surfaces treated with sprays or dusts* Fish oil, when used in a spray, increased the adhesion of DDT on surfaces exposed to outside weathering* The foliage of peanut plants grown in soil containing DDT was not toxic to the beetles. In field-cage tests under different weather conditions a concentrated spray remained effective longer than a dilute spray, and the dilute spray was effective longer than a dust. Applications of 50 and 100 pounds of DDT per acre in the upper 3 inches of soil gave appreciable mortality of beetles caged on the treated soil. No foliage injury was observed on cotton, peanuts, corn, and velvetbeans in field plots that received repeated applications of IDT as a 2.5-per- cent dust, a dilute spray, and a concentrated spray 9 — Young (381 ) ; also Packard (285 ) • Pi8sode3 s t rob i (Peck) , the white pine weevil Preliminary tests indicate that a 1-peroent DDT emulsion controls this insect by killing the adult beetles coming to sprayed trees.— Craighead and Brown (125 ) • Sitophilus granarius (L.) , the granary weevil A complete kill of adults in wheat was obtained at the end of the first week with a 0.05 percent dosage of DDT. A 3 percent DDT-pyrophyllite dust was highly effective after the third week at 15 p.p.ra. of DDT.— Cotton _et al. (120 ) • DDT (5 and 10 percent in pyrophyllite) when mixed with grain at the rate of 1 ounce per bushel gave 100 percent control of grain- infesting insects in dry wheat and corn. One-percent DDT at twice this dosage gave 99.5 percent control in wheat and 95.4 percent control in corn. Two hogs were fed corn treated with 10-percent DDT at 1 ounce per bushel. On a basis of 100 pounds body weight, each animal consumed about 283 mg. of -92- ri^rr per day. The hogs remained normal in behavior and pained 31.5 pounds of weight each over a 30-day period.— Farrar ( 150 ) . The granary weevil, which is the most injurious grain insect, has teen almost entirely eliminated from granaries with DDT (applied 1 to 5 times) both in larval or full grown stage.—Ahlberg and Mathlein (69). A DDT-dust mixed with wheat (1:20,000) was effective against the granary weevil.-- Smallman (322) . Almioide dust containing 8.9 percent of DDT idien mixed with wheat 1:20,000 killed 100 percent of granary weevils within 9 days.— Ross (306 ) . Sitophilus oryz a. (L.), the rice weevil In a test with seed wheat (12 percent moisture content), 0.05, 0.025, and 0.005 peroent by weight of technical DDT was added to 500-gram samples. The samples were put in glass jars with adult weevils. At the end of the first week all three dosages gave a complete kill. In a similar test a 3 percent DDT-pyrophyllite dust was highly effective at 15 p. p.m. of DDT after the first week. Samples of wheat of 14 and 16 percent moisture content were treated with DDT at the rates of 0.05, 0.1, and 0.2 peroent by weight, iiach sample was artificially infested with 100 adult weevils, and 10 days later all insects were dead.— Cotton et al. (120 ) ; also Packard (285) . Gesarol dust (3 percent DTVr) when mixed with rice 1-1,000 killed all weevils in 30 hours; at 1-2,000 it killed all in 48 hours; at 1-10,000 the insecticide had practically no effect after 6 hours and 48 hours elapsed before nearly all the weevils acquired a toxic dose; at 1-50,000 practical- ly all weevils were destroyed after 72 hours.— J. (224 ) . Two lots of seed corn, with 300 rioe weevils added to each lot, were treated with a 3-percent DDT dust at 2 ounces per bushel on April 14 and stored in barns at Clemson and at Summerville, S. C. They were insect fr©« on November 14. DDT gave complete protection and germination was not affected. Untreated lots of corn were badly eaten and heavily damaged by the rioe weevil, Angoumois grain moths, the cadelle, and other stored grain insects. — Cartwright (108) . Dermestidae At ta genu s piceus (Oliv.), the black carpet beetle Larvae of this insect were reedily killed when confined on a surface deposit of 20 mg. of DDT per square foot, applied as a talc dust. Resi- dues from sprays containing W in Deobase or other solvent were less effective, but did give control at higher concentrations of DDT.— Goddin and Swingle ( 179) . -93- Dermestes lardarius L., larder beetle In laboratory tests 1 percent of DDT in kerosene gave 100 percent kill within 8 hours by direct contact, and complete, but much slower, kill (after more than 3 days in some oases) when used as a residual poison on filter paper*— Ross (306 ) • Dermestes vulpinus F«, the hide beetle A spray containing 0.1 percent of DDT in acetone-Deobase (90-10), applied direotly on adult beetles, paralyzed them within 1 hour, but all recovered in 6 hours,-- Goddin and Swingle (179). Elateridae Agriotes lineatus (L«) Agriotes obscurus (L.) By watering endive seedlings with a 2-percent suspension of Gesarol (5 percent DDT) at the rate of 100 cc. per plant almost complete protec- tion against wireworms can be achieved .--Goigy Colour Co. (166) • Limonius agonus (Say), the eastern field wireworm In one plot of an early planting of cabbage seriously damaged by this wireworm, rows were opened and a 1-percent "DDT dust v/as applied in open furrows at the rate of 10 pounds of DDT per acre. The dust was thoroughly mixed with the soil in a band about 6 inches wide, rows were remade, and new plants set. In another plot roots and stems of cabbage plants were dipped in a suspension of 1 pound of 20 percent DDT in 1 gallon of water and transplanted* In other tests DDT added to dichloro- ethyl ether was applied at the rate of 1/8 gram per plant in comparison with dichloroethyl ether alone. In the first two treatments wireworms were not affected. The treatment affected growth and the plants eventual- ly died. The DDT-dichloro ethyl ether treatment was equivalent to the same dosage of dichloroethyl ether alone.— N. J. Agr. Bxpt. Sta. (275) • L i monius californicus Mann., the sugar-beet wireworm Limonius oanus Leo«, the Pacific Coast wireworm At Walla Walla, Wash., where the sugar-beet wireworm and the Pacific Coast wireworm were used in laboratory tests, the indications are that long periods are required to kill wireworms with DDT and that this ma- terial does not act as a repellent. The wireworms killed by DDT appear to be desiccated, as though affected by a strong alkali or exposed to drying, whereas those killed by fumigants are usually stiff and bloated. -94- In one series of experiments begun in May and repeated in July and August 1944, DDT was thoroughly mixed with tha top 9 inches of garden soil and wireworms were caged within the treated soil. The mortalities at the end of 6 weeks' to dosages of 16, 32, 48, and 320 pounds of DDT per acre were 63, 69, 85, and 98 percent, respectively, as compared with 27 percent in untreated soil. The surviving wireworms, many of which were inactive, were placed on moist blotting paper in salve tins and ob- served for an additional 6 weeks. The mortality at the end of the 10 weeks was 99 percent for the 16-pound dosage and 100 percent for the others.— White (373) . Limonius spp. Dusts containing 5 or 10 percent of DDT were used at the rate of 1 pound per 100 pounds of potato seed pieces. Treatments were made and potatoes planted on April 19 in experiments on two fprms. Wireworm lar- vae were first noted feeding on the seed pieces on May 7. Treatments had no effect on wireworms and did not affect the growth of the potatoes. — N. J. Agr. Expt. Sta. (276) . Eumolpidae Glyptoscelis squamulata Crotch, the grape bud beetle In preliminary tests DDT gave favorable results .--Baker and Porter (81). Meloidae Rplcauta lemniscata (F.), three-lined blister beetle Macrobasls fabricii (Lee), the ash-gray blister beetle Tests with a 3-percent DDT dust gave complete control in 18 hours. — Okla. Agr. Expt. Sta. (278 ); Hamilton (200 ) . Epicauta spp», blister beetle A 3-percent DDT dust was effective in Missouri.-- Has eman ( 203) . A knapsack sprayer was used in making 5 applications of 20-percent DDT spray on early potatoes and 3 applications on late potatoes. Blister beetles were not serious .--Gould ( 184 ) * Ostomidae Tenebroides mauritanicus (L.), the cadelle In the first test as described under Sitophilus oryza , at the end of 5 weeks, 20, 48, and 76 percent of the lari^ae were still alive in the -95- jsrs treated with the 0.05, 0.025, and 0.005 percent of DDT. In the second test a 3-percent DDT rfust killed all the larvae after the fifth week at 30 p.p.m. of DDT. The use of a DDT-oil spray may be the best means yet discovered for destroying infestations persisting in wood- work. In a third test, the interior walls of some bins were sprayed with a refined odorless kerosene containing 6 percent of DDT. A few days later the floors of the bins were littered with large numbers of dead adults and larvae. In one bin 8,000 dead cadelles were swept from the floor at the base of 10 feet of sprayed wall, and the killing action persisted for some time.— Cotton et ctl* (120 ) . See Sitophilus oryza .— Cartwrlght (108 ) . Scarabaeidae Autos erica castanea (Arrow), the Asiatic garden beetle A single spray of 1 pound of DDT in 100 gallons of water plus % pound of Areskap was applied to chrysanthemum plants with a knapsack sprayer. The day after spraying, 60 beetles were caged over the treated plants. After 2 days a 91 peroent kill of beetles resulted. No further injury occurred on the sprayed plants.— II. J. Agr. Expt. Sta. (275). When DDT was appliea at rates of 20, 30, and 50 pounds per acre to infested soil in a nursery the 20-pound-per-scre treatment caused a reduction of 99 percent and the heavier dosages 100 percent in larval population.— Ha dley and Fleming (196 ) . In preliminary tests DDT gave favorable results in the control of the grubs.— Baker and Porter (81). Cyclooephala boreal is Arrow, an annual white grub Same as for ftrfcoserica castanea .—Baker and Porter (81) ♦ Macro dactylus subspinosus (F.), the rose chafer Grape foliage and clusters were sprayed with DDT (1.5 pounds in benzene-kerosene anulsion per 100 gallons of water) on June 5, and 25 beetles were put in each of 2 cages on June 5, 8, 13, and 17. All the beetles were knocked down in less than 24 hours and were dead in less than 48 hours.— Baker and Porter (81). In the insectary 3-percent DDT dust gave 100 percent control with- in 18 hours of beetles placed on dusted foliage up to 4 days after treatment. In field tests dusted roses remained free of beetle attack but untreated blossoms were destroyed.— Ross (306) . -96- A spray of 1 pound of DPT in 100 gallons of water, together with a conditioner, gives excellent protection against the rose chafer. A 10-percent DDT dust controls the rose chafer •--Huts on (220). Phyllophaga spp., white grubs In a few preliminary tests Gesapon No. 18, at a dilution of approximately 8 ounces of DDT per 100 imperial gallons of water had no apparent effect on eggs, and little or none on 6econd-instar grubs when the emulsion was either poured or injected into the soil.— Ross (306 ) . In a single test at Lafayette, Ind», a dust containing 5 peroent of DDT applied to the soil in a cage at the rate equivalent to 242 pounds of DDT per acre and washed in with a copious sprinkling of water had no effect on the white grubs that had been placed in the soil. Young corn plants about 8 inches tall were visibly affected. This was a very pre- liminary experiment, however, and cannot be considered conclusive.— Packard (285) • Popillia japonica Newnu, the Japanese beetle Preliminary tests with J3DT in 1943 indicated that this material was the best protective agent ever used against the adults and that it appeared very toxic to the larvae in the soil. The tests were continued in 1S44 on a much larger scale. Laboratory tests indicated that the duration of effectiveness of DDT may be reduced when it is used with bordeaux mixture, wettable sulfur, lime-sulfur, or tank-mix copper phosphate, but Fennate did not seem to modify its effectiveness. In field tests one application of a spray containing DDT 1 lb., pyrophyllite 1 lb. (micronized together), fish glue solution 1 pt. (l lb. of liquid glue per gallon^ summer oil emulsion 1 quart, and water to make 100 gallons at the rate of 1 pound per 100 gallons, at or just prior to the beginning of the beetle season, gave satisfactory protection to the fruit and foliage of early ripening peaches and apples, blueberries, and miscellaneous ornamental and shade trees and shrubs. As many a6 three applications were necessary to give satisfactory control on grapes on account of the development of new growth during the beetle season. Flowering plants and ornamentals producing blooms and new growth while the beetles are flying also required up to three applications. In other field tests, turf and nursery plots were treated with DDT applied as a spray or dust* "When applied as a spray, the 50-peroent micronized DDT- pyrophyllite mixture was U3ed at 2 pounds to 100 gallons of water. The best dust mixture consisted of DDT 10, pyrophyllite 10 (micronized to- gether), talc 78, and tricalcium phosphate 2 percent. The results in- dicate that this material is more toxic than lead arsenate and that a dosage of 25 pounds per acre, applied either as a dust or as a spray, will practically eliminate the larval population.— Kadley and Fleming (196). -97- Effective control of Japanese "beetles attacking silking; corn ear tips was obtained with dusts containing 4 percent of DDT or 4 percent of a DDT byproduct (primarily a mixture of dichlorodiphenyltri- chloroethane, dichlorodiphenyldichloroethane, and the o,j>-isomer of DDT). The counts, in beetles per ear, were 0.11 and 0.04, respectively, for the treatments, and 6.10 for the control. Corn dusted with these ma- terials contained 1*0 and 1*2 European corn borers per stalk, with 2.8 as the average for the control. In another test the 4 percent DDT dust and a spray containing 0.8 pound of DDT per 100 gallons reduced the av- erage borer population to 0.6 and 0.8, per stalk as compared with 2«6 in the control.— ITolfenbarger et al. (3 79 ) . "DDT is promising. It is a very effeotive soil poison. We can get as good initial control of this beetle in the soil with 15 pounds of this roarerial per acre as with 500 pounds of lead arsenate per acre. Probably the most important development in respect to the Japanese beetle has been the use of DDT, which has proven very effective on the larvae in the soil and apparently is more toxic than any other material. We have obtained very excellent control of the adults by using one-six- teenth of a pound to 100 gallons of water. With one application of stronger concentrations we have been able to get protection on peaches from these beetles for the full season. The result this year with DDT alone is the most promising thing we have obtained yet, but the results on control with milky disease are. very good."— Annand (74). In laboratory tests as little as 1/16 pound of DDT in 100 gallons of water was as efficient as 6 pounds of le*ad arsenate. In combination with most fungicides it was slightly less effective. In field tests one to three sprays of DDT (micronized with equal parts of pyrophyllite, and with glue as a wetting agent), applied at the rate of 1 pound per 100 gallons, gave almost complete control of the beetles on peaches, early apples, grapes, blueberries, ornamental and shade trees, and shrubs. Applications after the first spray were necessary largely to protect new growth. DDT applied in spray or in dust form was also very effective in soil treatments against the grubs. In tests with 28 different soils 25 pounds of DDT per acre was more effective against third-instar larvae than 1,000 pounds of lead arsenate, and the effectiveness of the DDT in the soil was not ohanged during the period of the tests*— Baker and Porter (81) . A DDT aerosol gave excellent kills.— Ditman (133 ) . Three sprays of DDT (same treatment as for grape leafhopper) gave very good control of Japanese beetle on grapes.~N. J. Agr. Sept. Sta. (275). After an application of a DDT spray to sweet grapes (New York Muscats) wasps, bees, and Japanese beetles disappeared.— Bromley (96) • -98- DDT was applied aa dusts (3 and 5 percent) and as a spray (4 pounds of a wettable powder containing 25 percent of BDT per 100 gallons) on grapes. Fewer specimens were found on the treated plants than on un- treated plants but no dead beetles were found beneath or near the treat- ed plants. Smaller leaf areas were consumed on the plants treated with DDT than with any of the other materials tested.- Polivka ( 294 ) . Scolytidae Dendroctonus engelmarmi Hopk., the Engelmann spruoe beetle Preliminary results indicate that these beetles were prevented from attacking green logs in the laboratory by the application of DDT in an oil emulsion, and finally all wero killed.— Craighead and Brown (125 ) . Scolytus multistriatus (Marsham) , 1he smaller European elm bark beetle In extensive experiments conducted at korristown, N. J., solutions and emulsions containing 2 to 5 percent of DDT prevented crotch feeding in living elm trees by adult beetles for more than 110 days. Lower concentrations of DDT were effective for shorter periods. Similar sprays containing as little as 0.25 percent of DET prevented beetles from enter- ing the bark of sprayed logs for over 69 days, and sprays containing 2 percent of DDT gave protection for more than 160 days. An emulsion con- taining 0.5 percent of "DOT, when applied to elm wood infested with larval broods, permitted some emergence of adults, but affected tne emerging beetles to the extent that none were able to attack suitable material caged with them. Solutions of as little as 0.25 percent of DDT, when applied to similar infested material, prevented all em erg enoe.— Craighead and Brown (125 ) • Scolytus rugulosu8 (Ratz.), the shot-hole borer In California three almond trees were treated with a DDT spray but the effect on the borers was not determined. —Swans on and Michelbacher (340). Ambrosia beetles Bark beetles See under Cerambycidae .— Craighead and Brown (125 ) • Tenebrionidae Blapstinus auripilis Horn, a darkling beetle In a cage test 100 percent kill of this insect was obtained in 67 hours with 2 percent DDT. — Loftin (247). -99- Tribolium castaneum (Hbst.), the red flour beetle Same as the first test of Sitophilus oryza .— Cotton et al. ( 120 ) . Trlbolium oonfustnri Duv., the confused flour beetle Same as the first and s eoond tests of Sitophilus oryza . In a third test, garden seeds in paper envelopes were treated with 0.65 percent of DDT, repackaged, and placed with untreated lots in a special cabinet. After 2 months the treated seeds were undamaged while the untreated seeds were heavily infested. In a fourth test, spraying with odorless kerosene containing 5 peroent of DDT cleaned up an infestation in a wallboard partition of a flour-storage room. In a fifth test, kraft bags were treat- ed in three ways— by dipping in a 10-percent solution of DDT in acetone, by painting one side with varnish containing 10 percent of DDT, and by coating one side with a clay coating liquor containing 10 percent of DDT. The bags were filled with flour, tightly sealed and exposed to a heavy infestation of flour beetles. All the treated bags resisted penetration by these insects for many months, whereas bags made of untreated kraft paper were usually penetrated within a few days. In a sixth test, ordi- nary ootton flour bags and No. 5 kraft paper bags were treated with 5 percent of DDT in carbon tetrachloride. Considerable resistance to beetle attack was imparted to both types of bags by impregnation with DDT. --Cotton et _al. (120 ) . A DDT dust mixed with wheat 1 to 15,000 was effective.— Smallman (522). Within 5 minutes after 100 adults in a box about 18 inches square were sprayed with a 5-percent UPT solution all were dead or incapacitated. Another 100 adults put in the same sprayed box 24 hours later were soon killed by the residue. In a similar box sprayed and allowed to stand for 30 days before 100 beetles were introduced, 24 hours were required before the insects succumbed. In other tests the beetles were killed only in the adult stage and DDT was not effective against the eggs, lar- vae, and pupae .--Davis (129 , 130 ) . Almicide dust containing 18 percent of DDT when mixed with wheat 1:15,000 killed 90 peroent of confused flour beetles within 10 days.— Ross (306 ). Miscellaneous Coleoptera . Examination of the ground under hairy vetch at Oregon City, Oreg., disclosed that 5-percent DDT dust had killed insects of several species, including many beetles (nitidulids, carabids, silphids, elaterids, cocoinellids, and Diabrotica 11 -punctata Mann.), flea beetles, weevils (Sitona sp. and Brachyrhinu3 sp.), and pea weevils. Coccinellid larvae, which were abundant, appeared to be unaffeoted. Some of these insects. -100- especially coccinellid beetles, were also found dead on the rotenone dust and bait-spray plots. There were no ill effects on the operators, who found DDT to be much less irritating than the rotenone dust.-- Rockwood and Reecher (303 ) • NEUROPTERA Chry6opidae No chrysopid eggs were observed on the fruit or foliage of a Bartlett pear orohard in the Sacramento River area, California, which had been sprayed with DDT.~ Borden and Jeppson (91) • LEPIDOPTERA Aegeriidae Bembecia marginata (Harr.), the raspberry root borer The following materials were applied one, two, and three times to separate plots: A spray of 5 pounds of DDT in pyrophyllite (20-80) plus l/2 pound of soybean flour in 100 gallons; a 3-peroent DDT dust applied with an ordinary hand crank duster at the rate of 40 pounds to the acrej and a DDT- di chl or o ethyl ether emulsion which contained 1 pound of DDT to 100 gallons. Only the DDT- pyrophyllite spray treat- ment gave any marked reduction of borers over the check and the single spray was nearly as good as two and three applications. In 1943 tests the emulsion treatment gave a marked reduction over the check.— N. J. Agr. Expt. Sta. (275 ). Melittia satyr iniformis Hbn., the squash borer This insect was controlled with Gesarol A-3 dust as described for Anasa tristis .—Parker (287 ) • A 3-percent DDT dust and a spray containing 1 pound of actual DDT in 100 gallons of water gave control comparable to a 1-percent rotenone dust on squash borer.— N. J. Agr. Expt. Sta. (275 ) . In plots treated with 3-percent DDT dust 86 percent of the plants were uninfested as compared with 58 percent for plots treated with 35 percent cryolite and 20 percent for untreated plots.— Tate et aJN ( 342 ) . Synanthedon pictipes (G. and R.), lesser peach borer A solution of 150 grains of DT7T in 500 cc. of ethylene dichloride was emulsified with an equal part of water and painted on infested cankers on peach trees in May. Results taken in November showed an av- erage of 4 feeding borers in each treated canker and 5.5 in each check. — Ross (306) • -101- Arctiidae Hyphantria cunea ( Dr ury), the fall webworm This inseot was readily controlled with emulsions containing 0.1 to 1 percent of DDT.— Craighead and Brown (125 ) . Fall webworm nests were destroyed by a 3-percent DET dust, all the larvae dropping out and falling to the ground within 24 hours.— Fluke and Pond ( 157) . Cither oniidae Anisota rubicunda (F»), the green-striped ^aple worm In a Vermont maple-sugar orchard an aerial application of DDT (5 pounds of DDT in 5 gallons of solvent per acre) used against the gypsy moth gave complete control of this maple worm*— Craighead and Brown ( 125 ) • In treatments applied from an airplane against the green-striped maple worm, the spray was mixed at the rate of DDT 1 pound, cyclohexanone 1 pint, and a horticultural spray base heavy oil about 7 pints (enough to equal 1 gallon of mixed spray) .— Dowden et al. (156 ) • Coleophoridae Coleophora malivorella Riley, the pistol casebearer In preliminary tests with DDT favorable results were obtained in the control of this insect on apple.— Baker and Porter (81). Crambidae Crambus topiariu3 Zeller, the cranberry girdler DDT was applied to cranberries in New Jersey as a dust before bloom and as a spray to wet the chaff after bloom. It appeared that between 2,500 and 5,000 gallons of water per acre might be needed to spray the chaff with any degree of effectiveness* The length of girdler wounds, as percentage of total length of chaff-oovered stems, was 5»8 in an un- treated bog, 5.2 and 1.6 in areas treated with sprays containing 12^ and 25 pounds of DDT per acre, and 2*4 in an area dusted with 50 pounds of DDT per aore«— Doehlert (134) • Diatraea sacoharalls (F.), the sagarcane borer A pyrophyllite dust containing 10 percent of DDT, applied four times at weekly intervals at the rate of about 8 pounds per aore-application. -102- was inferior to oryolite against both first- and seoond-generation borers • A TOT spray (20 pounds of 10 peroent DDT-pyrophyllite plus 7 1/2 ounces of a sticker per 100 gallons) applied at the rate of 50 gallons per acre four times at weekly intervals gave 29 percent oontrol as oompared with 85 percent when synthetio cryolite dust was used* The inorease in borers in the DDT plots in the first experiment may have been due to its effect on Trichograrproa and other natural enemies of the borer under oonditions of a heavy infestation, when Triohogranma is usually more abundant.— Ingram et al. (222.) • DDT is not effective.— Annand (74). Geleohiidae Anarsla lineatella Zell., the peach twig borer One application of Gesarol A-20, at the rate of 2 pounds per 100 gallons of water, to an aprioot tree when the aprioots were 1/2 inch in diameter resulted in a crop of wormfree fruit.— Jones (252 ) . Gnorimosohema operoulella (Zell.), the potato tuber worm In laboratory tests larvae displayed a violent reaotion to DDT ma- terials applied direotly to them. They reacted faster to vapo-sprays than to 3-peroent EDT dust. Adult moths dusted or sprayed with the DDT combinations immediately lost power of locomotion, and died within 24 hours.— Lang e (242 ) . Thoroughly dusting seed potatoes with a 2 -percent DDT dust prevented them from becoming infested with newly hatched tuber worms.— Walker (365 , 566) . Kelferia lycoper3icella (Busck), the tomato pinworm DDT dust (5 peroent) and spray (4 pounds of a 25-percent wettable powder per 100 gallons) were more effective than oryolite dust or rote- none spray.— Neiswander (274 ) • Pectinophora gossypiella (Saund.), the pink bollworm DDT is the most effective material yet found against this pest but it causes an increase of aphids. In preliminary tests a combination of DDT with an arsenical was very good.— Annand (74). DDT is the most promising material that has been tested against this insect. At Presidio, Tex., DDT, cryolite, and mixtures of the two were compared -anisyl-l, 1, 1- tri oh lor o ethane 2 , 2-Di-p-t olyl-1, 1, 1- triohloro ethane 2 , 2-B i s (ja-ac etoxyph eny 1 ) - 1, 1 1 1-trichl oro ethane 2,2-Diphenyl-l,l, 1-trichloro- ethan© 2,2-Bis(D-chlorophenyl)-l,l- dichloroethylene 2,2-Bis(j>-bromophenyl)-l,l- dichloroethylene Lead arsenate Check (no treatment) (C 6 H 4 C1) 2 CHCC1 3 (C 6 H 4 Br) 2 CHCCl 3 23 (C 6 H40CH3) 2 CHCCl3 3 (CgB^CHj^CHCClj 7 (CEsCCOCgH^CHCC^ 99 (C 6 H 5 ) 2 CHCCl3 47 (C 6 H 4 C1) 2 C:CC1 2 85 (C 6 H 4 Br) 2 C»CCl 2 86 40 95 17 4 7 Siegler and Gertler (316)* Grapholitha moles ta (Busok), the oriental fruit moth Injury to peaches was reduced considerably in field plots sprayed with IDT, 1 pound per 100 gallons. Two applications, one eaoh ju3t be- fore the appearance of second- «nd third-brood larrae, were more effec- tive than one application made prior to appearance of the second brood. The H)T sprays reduced the aotivity of the parasite Maorocentrue ancylivorus Roh. t but did not eliminate it. At Moorestown, N. J», DDf sprays were much more toxic to the adults of the parasite than of the fruit moth, and the residues were toxic to them for a much longer period.— Baker and Porter tnt\ -109- One pound of IDT (Gesarol AK-20) per 100 imperial gallons of water was 87 percent efficient against a very light infestation.— Ross (306) • Two sprays of 1/2 pound of IDT in 100 gallons plus a sulfur fungi- cide brought about 85 percent reduction of oriental fruit moths in blocks of Elberta and Hale Haven peaches.— Hut son (220 ) . Polychrosis viteana (Clem.), the grape berry moth In small-soale tests at Sandusky, Chio, 1*5 pounds of DOT (emulsified with bensene-keroaene) per 100 gallons did not kill the eggs on grape berries, but was about 50 percent effective 20 days after application against larvae trying to enter the berries. In one field test this treatment was more effective when used in three or four applications than lead arsenate in four applications, but in another field test, one appli- cation of DDT did not hold up so well as one application of lead arsenate. In a field test with DDT, 1 pound per 100 gallons, on Niagara grapes in New Jersey, 16.6 percent of the berries were injured in the DDT plot, and 41*7 percent in the lead arsenate plot, but on Jersey Muscat grapes DDT was no more effective than the standard lead arsenate treatment .--Baker and Porter (j*l)« A DDT spray used against Popillia japonioa gave fair oontrol of this moth.— Hadley and Fleming (196 ). The efficiency of three spray sohedules as compared with an unsprayed check (efficiency lero) was as follows: Three sprays of lead arsenate and nicotine sulfate 75 percent, three sprays of lead arsenate and summer oil 81 percent, and one spray of lead arsenate with nicotine sulfate followed by two sprays of DDT, 1 pound per 100 imperial gallons, 73 per- cent.— Ross (306 ) . The grape berry moth was controlled by three sprays of DDT, 1 pound per 100 gallons.— Hutson (220 ). Laspeyresia caryana (Pitch) , the hickory shuckworm In preliminary tests DOT gave favorable results.— Baker and Porter (81). Melissopus latlferreanus (Wlsm.), the filbert worm In July DDT, Gesarol A-3 dust and A-20, 2 pounds in 100 gallons of spray, was applied with power maohines to 70 to 96 trees in three filbert orchards in the Willamette Valley at the rate of 65 pounds per acre— 10 to 12 gallons per tree. Results were favorable, but slightly less effective than with lead arsenate. Infestation in nuts was slightly more in the DDT-treated orohards than in the lead arsenate check.— Thompson (346) -110- Spllonota ooellana (D. and S.), eye-spotted budmoth Tn Nova Scotia one summer application of DDT 1 pound (powder suspen- sion) per 100 imperial gallons of water gave much poorer control than Black Leaf 155 and appeared to be no better than lead arsenate* At Simcoe, Ontario, a similar spray reduced the injury from 38#4 peroent in the check to 24«0 peroent when only the undersides of the leaves were covered, and to 21.8 percent where both surfaces were sprayed,— Ross (306 ) « Fhalaenidae Ceramioa plcta (Harr«), zebra caterpillar Gesarol A-3 duet (3 percent DDT) applied to one-third to one-half grown oaterpillars on oabbage plants caused all larvae to leave the plants and killed at least part of them within 22 hours, both when the dust was applied to the larvae on the leaves and to the leaves only. Dusting with talc alone caused very few larvae to leave*— Ross (306). Feltia subterranea (F.), the granulate cutworm See Diaphania nitidalis ♦— Cartwright (108 ) • Alabama argillacea (Hbn.), the cotton leafworm DDT was of no practical value for oontrol. At the Waco, Tex., laboratory, the median lethal dosage of a DDT suspension applied to the dorsa of fifth-instar leafworms was 61.5 mg. per gram of body weight, or 206 times as great as that for the bollworm. In field tests 3 or more applications of approximately 16 pounds per acre of 1, 2, 4, and 8 per- cent DDT dust applied with hand dusters at '"Faco, and 4 percent DDT dust applied by airplanes at Bryan, Tex», failed to prevent defoliation of plants. Field plots at Tallulah, La«, were defoliated following 5 appli- cations of 5-peroent DDT dust. At Presidio, Tex., where 8 to 10 heavy dust applications were made for the pink bollworm, DDT gave considerable control of the leafworm. At Waco cotton plants sprayed six times with DDT suspension at the rate of # 64 pound of DDT per acre-application caused a greater reduction of leafworms than plants dusted with the same dosage, but neither treatment prevented almost complete defoliation.- Loftin (247)* DDT is not so effective as the arsenioals. We may be able to over- come the leafworm with a combination of DDT with an arsenical.— Annand <££>. Autograph a sp. # a looper There was some indication that DDT in oil applied as a vapo-spray was effective at high concentrations.— Lange (241) . -111- Anagrapha faloifera (Kirby), the oelery looper This insect was completely controlled with one application of DDT, and reinfestation did not oocur for 5 weeks.— Russell (308 ) * Caenurgina sp» Examination of the ground under hairy vetch at Oregon City, Oreg., disclosed that a 5-percent DDT dust had killed insects of this species. — Rookwood and Reeher (305 ) • Heliothls armigera (Hbn.), the corn earworm, the tomato fruitworm, the Dollworm DDT was the only insectioide whioh proteoted the corn until harvest- tins* DDT in mineral oil gave almost complete control of the corn earworm in both the green and the maturing stages of the corn ears* Pyrethrum, styrene dibromide, and dichloroethyl ether were all less effective* Two highly refined mineral oils were used, Bayol (80-90 sec* Saybolt) and Superla No* 13 (120-125 sec* Saybolt)* £aoh inseotioide was tested in both oils, in the following concentrations : DDT 2, pyrethrum extraot (0*2 percent pyrethrins), dichloroethyl ether 2, and styrere dibromide 1 percent* They were applied at two dosages, 0*6 and 1*2 ml* of solution per ear*— Blanchard and Satterthwait (88)* "When silks of sweet corn were dusted heavily with Gesarol A-3, the reductions in wormy ears were 50, 40, and 30 percent in three tests*— Bwart (145)* In testing six methods of ear treatment the DDT- dusted plot had 3*56 of percent infested ears as against 7*26 peroent in the oheok and only 0*99 percent in the oil treatment*— Granovsky ( 187 ) • A 3-peroent DDT dust applied to the silks was effective.— Haseman (£03). Three applications of Gesarol A-3 dust to cotton showed only 8.3 peroent repellency against ovipositing moths.— Fletcher and Thomas (156 ) ♦ Dusting the silks of sweet corn with a 3 percent DDT dust materially reduced earworm infestation. Of 59 treated ears 32.2 percent were in- jured, whereas 86.2 peroent of 65 untreated ears were injured.— Cartwright (108) . DDT in the form of an aqueous suspension (0.5 pound) or an emulsion (1 pound per 100 gallons of water) gave perfect control of tomato fruit worms*— Owens (284)* -112- Comparative tests with DDT dust mixtures, calcium arsenate, and cryolite were made in southern California against the tomato frultvorm. Three applications were made at intervals of 2 weeks, at an average rate of 30 pounds per acre-application. The results, based upon the relative number of damaged tomatoes at harvesttlme, showed that a 10- percent DDT dust mixture gave 92 percent control, a 5-percent DDT mix- ture 77 percent, and a 2.5-percent DDT mixture 81 percent. By com- parison an undiluted calcism arsenate gave SI percent control, and a 70 percent cryolite mi xtur e 60 percent control. In another heavily infested experimental field 10-, 5? *&& 2.5-P»rcent DDT dust mixtures gave 97, gU, and 79 percent control, whereas the undiluted calcium arsenate gave 65 percent and the 70 percent cryolite 53 percent con- trol. At Norfolk, Ya., a 5~P«rcent DDT duet was as effective as undi- luted cryolite (90 percent) against this insect on Pordhook lima Deans. —White (373) > On caged cotton plants DDT dusts tested gave the following per- cent mortalities: Bk from h percent DDT, and 73 from 1:1 basic copper arsenate-eulfur, both applied at l6 pounds per acre, as compared with 62 from calcium arsenate, 65 from lead arsenate, and. 66 from cryolite (gg percent Ha-^Aiyg), each at 8 pounds per acre. A spray application of 0.6U poumd of DDT per acre did not kill so quickly as the same amount applied as a dust. Water. sprays at the rate of 1,28 pounds of DDT per acre caused 100 percent mortality of third-instar bollworms, at 0.6^ pound of DDT 89 percent, at 0.32 pound 66 percent, and at 0.l6 pound ^5 percent. In a field test two effective dust applications of DDT at l6 pounds per acre-application resulted in the following gains, In pounds of seed cotton per acre: 1^8 from 1 percent DDT, 15^ from 2 percent, 238 from U percent, and 230 pounds from 8 percent. Calcium arsenate at the same rate gave a gain of 273 pounds per acre. In a large-plot test four applications of a k percent DDT-pyrophyllite dust at 16 pounds per acre-application gave a gain of 73^ pounds of seed cotton per acre in comparison with 688 pounds from calcium arsenate at 15 pounds. —Loft in (2^7). One application of Gesarol A-3 dust to green silk of sweet corn gave approximately 75 percent control. The constriction method by twine applied at the same time gave nearly 100 percent control.— Parker (287). After treatments of tomatoes with cryolite-talc (1:1), cryolite- corn meal (1:10), calcium arsenate-lime (1:1), DDT 3 percent (Oesarol A-3) 1 and the untreated control the following percentages of fruits were injured by frultworms, 0, 1.7. 1.8, 0, and 2.4. — Wolfenbarger et al. (379) > A 3~P« r cent DDT dust was applied a day or two after the corn silks appeared, so that the young worm would be killed after emerging from -113- the egg and "before penetrating the silk. The method controlled the ear worm and the kernels developed full to the tip. —Russell ( 308 ) . In experiments in southern California corn fields heavily infes- ted with the corn earvorm, injection of white mineral oil containing 1 percent or more of DDT into the silks produced 85 *° 99 percent of wormfree ears. In Illinois 91 to 100 percent of wormfree ears were ob- tained by either injection or atomization of 2 percent of DDT in undi- luted white mineral oil.-- Packard ( 285 ). Hellothls virescens (P.), the tobacco budworm In a field experiment at Florence, S. C, a 10-percent DDT dust mixture applied in the buds of tobacco plants by different methods gave from 88 to 100 percent kill of the tobacco budworm in k days.— White (2D). Laphygma exlgua (Hbn. ), the beet armyworm In tests on caged cotton plants 2 percent DDT gave excellent re- sults. —Loft in (2^7). Prodenla praeflca Grote, the yellow-striped armyworm Insects swept from alfalfa were lightly dusted with a 3-p«rcent DDT dust (A-3) and held in an Insect net with alfalfa cuttings over night, About 50 percent of the armyworms were shriveled; when these were placed on fresh alfalfa cuttings and observed for 2U hours none of them fed.— Smith (32U). Trichoplusla nl (Hbn.), the cabbage looper A series of experiments on cabbage caterpillars was conducted in field plots in southern California, at Charleston, S. C, and at Baton Houge, La., against mixed populations, principally of the cabbage looper, the imported cabbage worm, the larva of the diamondback moth, and the cabbage webworm. Several species of Agrotlnae and Heliothls armigera (Hbn.) were also present. In the Charleston area DDT appeared to be more toxic to the cabbage looper than to either the imported cabbage worm or the larva of the diamondback moth, and also more toxic than either rote- none or pyrethrum to the cabbage looper. The results of these experi- ments seem to warrant the tentative conclusion that heavy infestations of these three species of caterpillars may be controlled effectively by a 1-percent DDT dust applied at 10-day intervals, the first application being made as soon as feeding injury is apparent. This conclusion is drawn without consideration or regard for the residue factor. In one ex- periment on plots of cabbage, collards, and broccoli, a 1-percent DDT dust mixture applied at 10-day intervals from the time the first true -llH- leaves appeared on the plants effectively controlled the cabbage looper, imported cabbage worm, and several species of Agrotinae. The same mix- ture was not effective against the cabbage webworm, but when the strength was increased to 2.5 percent adequate protection was obtained. — White (111). ?our applications of a 3-percent DDT dust gave good control; better than a 0.75-P ercent rotenone dust. Dusts containing 1 percent of DDT deposited from acetone or Velslcol AR-60 solutions gave even better con- trol. In other tests the leaf -damage rating of 1-percent DDT dust was practically the same as that of 0.5 percent rotenone, — Apple (75) » Greenhouse tests with this species gave results almost identical with those for Pierls rapae L. Gesarol A spray 10 pounds (DDT 8 ounces) was much more effective than 5 pounds of lead arsenate.— Boss ( 306 )« Cabbage plants were treated with DDT dusts (l/2 to 3 percent), applied at 28 to 30 pounds per acre. Sprays containing as little as l/2 pound of DDT in 100 gallons of water were applied at 125 *° 150 gallons per acre. In one test against thrips, DDT was dissolved in dichloroethyl ether (2U grams in 100 ml. total), emulsified, and applied at the rate of 1 pound in 100 gallons of water. These sprays and dusts gave outstand- ing control of the cabbage looper, the imported cabbage worm, and the diamondback caterpillar. None of the treatments compared favorably with nicotine sprays and dusts against cabbage aphid and turnip aphid. Re- sults with DDT sprays and dusts on Thrips tabaci Lind. and others were erratic. However, the DDT-dichloroethyl ether treatment gave 99«2 per- cent control of thrips in a heavy infestation. — N. J. Agr. Expt. Sta. (211). An application of Gesarol A-3 dust caused a complete clean-up 36 hours later. The larvae varied in size from half- to full-grown.— Janes (225). Cabbage worms and loopers were controlled with a 3~P e rcent DDT dust applied 5 times with a rotary hand duster to 70 plants of early cabbage. No larvae or damage were ever observed on the treated plants , whereas the checks were severely damaged. About a month after the last applica- tion of dustf larvae were found on the treated plants* Late cabbage and broccoli were treated with a 3-peroent DDT dust and a 20-percent DDT spray. Counts made after the fourth application showed neither worms nor loopers on the treated plants but 116 worms and 64 loopers on the untreated plants* Lice colonies were present on 4 plants in the sprayed plots, and on 2 plants in the dusted plots; there were none on the check. No injury to the plants. The spray did not adhere well to the plants. —Gould (184), -115- In 1944 cabbage in the Kenosha, Wise*, area was treated with dusts containing 3 percent of DOT, 0.5 percent rotenone, or 20 percent of oaloium arsenate. The DOT dust gave the best control and the average weight of the cabbage heads was greatest in the DOT- dusted plots. A spray containing 2 pounds of DOT (Gesarol AK-20) per 100 gallons of water gave better control than a cube spray or a lead arsenate spray each containing 4 pounds per 100 gallons.— Allen and Brunn (j[l) • See Pieris rapae .— Granovsky (187) . See thrips on beets (p. 43) .—Anon. (49) • Phaloniidae Anticargla gemnatilia (Hbn.), * ne velvetbean caterpillar Excellent control of this caterpillar on peanuts and soybeans was ob- tained with a single application of 3"P«rcent DDT dust or a DDT spray.- Packard (285). Phycitidae Acrobasis caryae Grote, the pecan nut casebearer A 0.20-percent DDT spray reduced infestation by about one-third.- Hamilton (200). Gesarol SH-5 a t 1/2 gallon per 100 gallons of water, and Gesarol A-20 at 2 pounds, reduced the infestation to Uh and Uo percent, as compared with 60 percent in the checks. Timing the sprays with hatching is very important. — Okla. Agr. Expt. Sta. (278). Hesults obtained with DDT were promising enough to warrant further tests.— Baker and Porter (81) . Ephestia elutella (Hbn.), the tobacco moth In laboratory experiments at Hichmond, 7a. , undiluted DDT was used in an acetone-oil solution. The solution was atomized into a modified Peet- Grady chamber. The test Insects were adults of the tobacco moth and the cigarette beetle. A 5 percent DDT-oil solution, used at the rate of 100 cc. per 1,000 cubic feet, resulted in 97 percenv kill of the tobacco moth in 3 days and 71 percent kill of the cigarette beetle in 5 clays, a 15-percent solution killed 98 and 90 percent of the moths and beetles, whereas pyreth* rum-oil spray (0.2 percent of pyrethrins) gave mortalities of 100 and U6 per- cent of the moth and beetle, respectively. A 10-percent DDT dust mixture, prepared by mixing pyrophyllite with an oil solution of DDT and then blown into the dust chamber at the rate of 3 ounces per 1,000 cubic feet, killed Us percent of the tobacco moths and 93 percent of the cigarette beetles. A -116- 15-percent solution of DDT in oil sprayed on packages of cigarettes did not prevent them from becoming infested during an exposure of 30 days.— White (373) . Itiella zlnckenella (Treit.), the lima bean pod borer Three applications of 3-percent dust (Gesarol A-3) were made May 21, 25 t and 26 on lima beans at the rate of 30 pounds per acre. Rains within 2U hours after the second and third applications washed off the dust. An average of 1+3.8 percent wormy pods occurred in the dusted plots and 36.2 percent in the checks.— Swart ( IU5 ). Mlneola vaccinii (Riley), the cranberry fruit worm Two applications of each of three dust mixtures were compared in a cran- berry bog in New Brunswick. The percentage of berries injured with the different mixtures were as follows: Gesarol A-3 dust (3 percent DDT) 3^»7i Lethane B71 35*^; gypsum-cryolite (70:30) ^2.U; check 75«5« I n tv0 other tests the Gesarol gave approximately the same results as the gypsum-cryolite dust. — Ross ( 306 ) . Plod la Interpunctella (Ebn.), the Indian meal moth In tests in grain-elevator bins pyrethrum applied either as a spray or an aerosol gave much better control of both adults and larvae of the Indian meal moth than did a DDT aerosol. The pyrethrum aerosol contained pyrethrum extract 5 percent (pyrethrins 1 percent), either oleic acid or oil of sesame 2 percent, and Freon 93 percent; the pyrethrum spray contained pyrethrum extract 10 percent (pyrethrins 0.^ percent) in a high-grade oil such as Deobase, Pensolene, or Imperial No. 9» aad. the DDT aerosol consisted of DDT 5 percent, cyclohexanone 10 percent, and Freon 85 percent. Adults were more susceptible than the larvae to DDT aerosol. In another test c kerosene spray containing 5 percent of DDT was applied to larvae on the ceiling of a grain store room. Only a few of the larvae dropped to the floor and 2k hours later there was no significant de- crease in the numbers of larvae on the sprayed areas. Test insects were exposed on wheat treated with small amounts of DDT combined with Almicide, a chemically inert mineral dust which has the property of promoting ex- cessive water loss from insects. Although the Almicide alone caused no mortality at the dosage applied (maximum rate 1 part dust in 15,000 parts wheat), it appeared to exercise a marked influence on the insects when combined with DDT, e.g. after 5 days' exposure, at a dosage of 1:28,000, undiluted DDT was not significantly more effective than the DDT-Almicide dust containing only 26.6 percent of DDT. ISheat mixed with IDT-Almicide dust (containing 18 percent of DDT) in the ratio 16,000:1 killed 15 percent of the larvae of the Indian meal moth after 10 days' exposure. —Ross (306). To 500-gram samples of wheat, 0.05, 0.025 and 0.005 percent of technicel DDT was added. The samples were placed in glass jars together with larvae of the Indian-meal moth. At the end of the first week all three dosages of DDT -117^ gave a complete kill. Seeds of watermelon, corn, tomato, and lettuce treat- ed with 0.05 percent of DDT were protected against infestation for 2 months, whereas untreated seed was heavily infested.— Cotton at al. ( 120 ). The larvae in a dairy building were apparently killed by a DDT residual spray.— Boss ( 306 ). Larvae appear to be resistant to DDT dust. ^Applied as an aerosol and as an oil-base spray under precautions, DDT was not so effective as pyreth- rum similarly applied. — Smallman ( 322 ). Pleridae CollaB eurytheme Boieduval, the alfalfa caterpillar f In laboratory tests a 3-percent DDT dust gave complete control in 18 hours. — Okla. Agr. Expt. Sta. (2JS). In laboratory tests Gesarol A-3 dust killed 100 percent of full-grown caterpillars. — Hamilton ( 200 ). Pieris rapae (L.), the imported cabbage worm In greenhouse tests on larvae collected in the field, this species was very susceptible to DDT with kills approaching 100 percent by sprays contain- ing as little as 2 to k ounces of DDT per 100 imperial gallons. A 15-day-olt spray deposit of DDT, which had been kept dry, was just as effective as a fresh deposit. Although DDT appeared to have no direct repellent action in the sense that larvae avoided the sprayed surfaces, it caused most of the larvae to leave the plant soon after they had done a very small amount of feeding on treated foliage, or after the insects themselves had been sprayed and placed on unsprayed plants.— Boss Q06). The imported cabbage worm, the cabbage looper, and the diamondback moth were completely controlled by a 5-psreent DDT dust in combination with 5 per- cent of yellow copper oxide in pyrophyllite dusted lightly five times during the season. The plants in the check plots were so badly riddled that not a single edible head was formed. The DDT dust was by far the most effective of several insecticides tried. The cabbage plants treated with a DDT com- bination were absolutely free from holes and assumed a healthier and con- spicuously greener appearance in comparison with all other plots. — Granovsky (1§I>- Same as for Trichoplusla nl (Hbn.). — Allen and Brunn (71); Apple (75). A trial dusting of cabbage with a 3-P«rcent DDT dust gave perfect con- trol of cabbage worms, whereas an adjacent row, untreated, was badly riddled by worms.— Cartwright (108). -118- The cabbage worm, cabbage looper, and diamondback moth were controlled completely "by applications of Gesarol A-3 (3-P© r cent DDT) dust to cabbage every 5 weeks from May 15 until harvest, July 15. This dust apparently in- creased growth slightly and prevented head splitting at maturity when re- newed growth started due to rain.— Parker (2 8J ) . See Trlchoplusla nl.— White (373) ; H. J. Igr. Expt. Sta. (275). The treatments used were as follows: 1, 2, and 3 percent DDT dusts (talc base), l/2, 1, and 2 percent DDT sprays, an emulsible liquid spray, 1 ounce of the active ingredient in 100 gallons of spray, and a paris green spray. The 1-percent dusts and l/2-percent sprays gave as good control as did the higher concentrations when applied every 2 weeks. An emulsible DDT liquid spray gave perfect protection against all the cabbage worms for 2-3 weeks when applied at a rate that gave only 1 ounce of the active in- gredient in 100 gallons of spray. At one time 5 weeks elapsed between treat- ments on the plots dusted with a 3-p«rcent DDT dust. At the end of this period only 3 percent of the plants were infested with worms as compared with 50 percent on the paris green plots, which had "been sprayed every 2 weeks. The untreated plots showed an 80 percent infestation.— Russell ( ^08 ). Plutellidae Plutella maculipennis (Curt.), the diamondback moth A dust containing as little as 0.5 percent of DDT gave good control of this insect. An aerosol containing 3 percent of DDT also gave excellent control of this pest on large broccoli plants.— Walker Q65 » 366 )» Psych idae Thyrldopteryx ephemeraeformls (Haw.), the hagworm Actively feeding bagworms were removed from a badly infested sycamore tree and placed on uninjured foliage from a nearby tree. In the laboratory, a single spray of DDT, at the rate of 1 pound of DDT in 100 gallons of water plus l/^ pound of Areekap, was applied to branches containing bagworms. The infested tree was also sprayed. In the laboratory test 28 percent of •the bagworms "were dead 2k hours after treatment. The tree was half defoliat- ed and heavily infested when treated. Defoliation was completed after spray- ing. — N. J. Agr. Expt. Sta. (275). This Insect was readily controlled with DDT (0.1 to 1 percent) applied as an emulsion in small-scale tests. — Craighead and Brown ( 125 ). Pyralididae Dlatraea sac cha raits (P.), the sugarcane borer A 10-percent DDT dust was less effective than undiluted cryolite. — Packard (285). -119- Pyraustidae Diapftania h yalinata (L.), the raelonworm D. nitidalla (Stoll), the pickleworm In tests oonducted for the control of these insects on cantaloups, a dust containing 3 percent of DDT gave very promising results •— Walker (366 , 366) . Three applications of Gesarol A-3 dust at the rate of 30 pounds per acre reduced cantaloups infested with the melonworm to 2*6 percent* No burning of plants resulted*- Ewart (145 ) • A 3-peroent DDT dust was effective against pickleworms on squash and cucumber* Untreated cantaloup plots produced 359 cantaloups, 12 of which were damaged by the pickleworm and 165 by the granulate outworn. Feltia subterrane a (F«) • Plots dusted four times with DDT produced 358 cantaloups, only 1 of which was danaged by the piokleworm*— Cartwright (108), A 3-peroent DDT dust was about equal to a 33-peroent cryolite dust against piokleworas in field tests in North Carolina* A 1-peroent DDT dust gave considerable control*— Pulton (162) * An acre ef oantaloups infested with piokleworas was divided into 60 plots, dusted*, and each treatment replioated 10 times* Dusting be- gan at blooming and was continued at weekly intervals until 10 days before harvest* Pour applications were made at concentrations rang- ing from 15-20 pounds per acre to 25-30 pounds per aore. The average percentage of infested melons at harvest was as follows: 1-peroent DDT 5*5, 2-percent DDT 4*4, 3-percent DDT 4*4, l/2-percent rotenone 8.9, 30-percent eryolite 7*3, and cheok 11.2*— Lyle (249 ) . Hellula undali s (F*) , the cabbage webworm Same as for Triohopluala ni.— White (373) • Loxostege aimilalis (Guen.) , the garden webworm A DDT aerosol gave excellent kills of garden webworm on spinach.— Ditman (133) • Pachyzanola phaeopt oralis (Guen.) , a grass webworm A 10-peroent DDT dust applied to a lawn at the rate of 10 pounds per aore killed more than 90 peroent of these larvae. The principal grass in this lawn was oarpetgrass (Axonopus oompressua ( Swart*.) Beauv.).- Ingran jat al • (222) • -120- Phlyctaenia rublgalia (Guen*), the greenhouse leaf tier Greenhouse tests shoved that this species had about the sase degree of susceptibility to DDT as the diamondbaok moth*— Boss (506) • Pyraueta nubllalis (Hbn*), the European corn borer In 1944 -ttiree applications of DDT with ground-sprayer equipment near Toledo, Ohio, at 5-day intervals to early-market sweet oorn gave excellent borer control. A 10,8 percent DDT-pyrophyllite dust gave 97.9 percent reduction of borers in the plant and 99.2 percent reduction in the ears, when applied with a wheelbarrow sprayer run by a gasoline engine and applied with a hand nozzle that produoed a solid cone of spray* Four applications of dusts containing 0*75, 1.5, 5, and 6 peroent of DDT in pyrophyllite were made 5 to 7 days apart with a ground machine to sweet oorn. in dosages of 0*5, 0.6, 1*2, and 2*4 pounds per acre-applioation* Borer reduction increased with each increase in the dosage, and at the highest rate provided 95 percent reduction of corn borer larvae infest- ing the ears, even though the applications were begun too late for best results against newly hatched larvae. The yield resulting from treat- ments applied at a rate of 2*4 pounds of DDT per acre-application was graded 89*9 percent salable and 86*1 peroent No* 1 and borer-free • On the variety Evergreen four airplane applications 5 to 5 days apart of a concentrated spray containing 8*9 peroent of DDT in white oil, at the rate of about 2*25 gallons per acre, provided borer reductions in plants of 98 peroent, with all ears salable size and borer-free in the center rows of -the treated swath* DDT in dust form applied by airplane to the same variety was somewhat less effective tbju* the oonoentrated spray* Aerial dust treatments resulted in 82*5 percent reduction of borers in -the ears, and a yield in which 85*6 percent of the ears were Ho* 1 and borer-free* All treatments resulted in an inorease in the number of salable ears per plot* Tests were also made with Gesarol spray insecti- cide (.5 peroent DDT)* Areskap was added to all sprays at the rate of l/S pound per 100 gallons of water* The oonoentrated spray contained the following ingredients i DDT, technical (GHB-A-DDT) 0.67 j Solvent, petroleum distillate 1*54; white-oil vehicle, Superla grade (125 seconds Saybolt) 5*36; and emulsifying agent (Triton X-100. an aralkyl polyether alcohol)' 0*16 pound per gallon.— Batohelder and Questel (S3) ; also Paokard (285) * A spray containing 4 pounds of cube (5*5 percent of rotenone) and 6 ounces of Areskap per 100 gallons of water, applied on four dates, gave a oontrol of 80 percent, whereas a spray containing 0*026 peroent of DDT gave a oontrol of 77 peroent* A 5-peroent DDT dust gave a con- trol of 67*5 peroent. With a 0.026-percent DDT spray, applied 4 times with a power sprayer and a three-row boom carried over the corn the control was 96*2 percent, iihereas, a 0*024-peroent rotenone spray gave 96.1 percent control.— Apple (75). -121- DDT Is promising for this insect.— ^Annand (7*0* DDT is being tested against the European corn borer, and the results have been very encouraging, particularly in sweet com, — Aamodt (60). A Byania insecticide gave better results than 3 percent DDT against the corn borer in Sew Jersey, but the percentage of salable ears of corn produced were about the same with both treatments. — AIF (6)5). Five applications of a 3-P«rcent Gesarol dust were applied with a rotary hand duster June 7» H» l6, 20, and 25, 19^ « to two 15-stalk rows of Golden Cross Bantam sweet corn as a plot replicated six times. Most larvae had left the stalks by harvest time, July 26 and 27. Dissections of stalks showed that 9 percent of the treated plants and 62 percent of the untreated plants had been infested. There was no Injury from the treatment. Plants treated with a cube spray (k pounds of a 5-porcent rote- none material in 100 gallons) had l.U. percent of the stalks infested. More research is needed before recommendation.— -Gould ( lffi ). A 3-porcent DDT dust gave a greater reduction in both the first and second generation borer population than a 1-percent rotenone or a ^-per- cent nicotine dust. The DDT interfered with growth of the corn.-— B. J. Agr. Ixpt. Sta. ( 275) » gee Bapoasca fabae ; also Popilia japonica .— tfolfenbarger et al . ( 379 ) * Sphingldae Ceratomia catalpae (Bdv.), the catalpa sphinx The larvae were readily controlled with DDT (0.1 to 1 percent) applied as an emulsion In small-scale teste*— Craighead and Brown ( 125 ). Protoparce quinquemaculata (Haw. ) , the tomato hornworm A small number of full-grown larvae dusted with Gesarol A- 3 immediate- ly showed signs of severe Irritation by violently swinging the anterior half of the body from side to side, together with defecation and excessive exudation of moisture. Later the larvae fell from the plant and all died after shrinking greatly. In a field test at Chatham, Ontario, tobacco plants were sprayed with DDT at l6, g, and k since* per 100 imperial gallons of water and in each case 100 percent control resulted. — Ross (306). A DBT aerosol gave excellent kills of hornworms on tomatoes. — Ditman (133). Same as Macrosiphum solanifolil (Ashm.). — H. J. Agr. Kxpt. Sta. ( 275 ) • -122- P. eecta (Johan.), the tobacco hornworm In field experiments at Florence, S. C. , and Oxford, H. C, neither a 5- o r a 10-percent DOT mixture gave a satisfactory reduction of the to- bacco hornworm. In laboratory tests at Oxford fifth-instar tobacco horn- verms were not affected by the 10-percent mixture, but the same instar of the tomato hornworm succumbed readily. In comparable tests with third ins tars 100 percent mortality of the tomato hornworm was obtained in 2k hours in each of seven replicates, whereas the mortality of the tobacco hornworm averaged 12 percent in 2^ hours and 35 percent in 196 hours. There was yery little feeding of either species on the treated foliage. — White (22); Stahl et al. (£1). Some caged tomato plants were dusted with 3 percent DDT and worms put on them, while others were dusted with the worms in place. More worms died when they were present to receive the dust. The percentage of kill was variable in the different tests, with about 50-P e rcent mortality. The tobacco hornwcrms were less affected than the tomato hornworms on the same plant.— Gould (IgU). Tineidae (Clothos moths ) Garments impregnated with DDT are mothproof and remain so for a very long time,— Buxton ( 100 ). Tortricidae Ar chip s argyrosplla (Wlk.) the fruit tree leaf roller Apple trees infested with nearly mature larvae were treated with a spray containing 2,5 quarts of 20 percent DDT in oil, with emulsifier (SH-20), per 100 gallons of water. Within a short interval after spraying, the larvae left the foliage and were hanging by their silken threads. Many dropped to the ground; none were found on the trees 4S hours after spray- ing, whereas unsprayed trees remained infested. The spray caused a spotted leaf injury.— Borden and Jeppson (j)0). Archips fumlferana (Clem.), the spruce bud worm Tests with high-powered ground equipment, conducted at Tort Collins, Colo., demonstrated that the spruce budworm can be controlled with dosages as low as 2.5 pounds of DOT per acre, applied as an emulsion in linseed oil or as a finely divided alcohol-water suspension. Some of the sprays were applied prior to larval activity in the spring; others were used when the larvae were one-half to full grown. There were indications that the early applications, which killed the young larvae as they began feeding, were partially effective in killing the moths several weeks later; therefore, -123- one treatment may result in control of two generate is ^f some species of insects.— Craighead and Broun (125) . In Canada a DDT insecticide distributed from a helicopter was ef festive.— Anosi. ^S) • Cyelohaxanoae-eil sprays containing 5 or 10 percent of DDT were applied with a hand atomiser and also by airplane at the rate of 6, 3 or 2 pounds of Biff per acre* The sprays killed apparently all adults at the time of application and the plots remained practically free of moths for the remainder of the season* in spite of their abundance in the areas adjoining the plots* Meths eat ©ring the plots and those emerging from pupae appeared to have been killed in considerable num- bers by -the DDT residue on tbe foliage. The sprays were not effective however, against the pupae, eggs, or hatohing larvae* Observations over a 6-week period showed only 10 percent mortality of the young larvae seeking, or in, their winter quarters*— -Ross (306) . It may be possible to control two generations of the spruoe bud- worm with one application of BDT» It is also probable that fairly good coverage at the beginning of an outbreak would prevent subsequent build-up of infestation, and satisfactory control might be obtained with only one application.— Sheals and Craighead (514 ) • At chips rosaceana (Harr.), the oblique-banded leaf roller DDT applied both as a dust and as a spray gave practically 100 percent control on 2 SO acres of raspberries and saved the crop* The deadly effect of the insecticide remained on the foliage for at least a month. The DDT was not unpleasant to handle and contrary to some fear, it apparently was not harmful to bees, even though the applica- tion had to be delayed until the full-bloom stage because of the late arrival of Hie material •— Burtner (99) • DDT is being recommended for the control of this insect in Oregon. — Childs (110) . Experiments carried on in the laboratory at Corvallis, Oreg., in the winter of 1943-44 proved that the DDT applied to the raspberry foliage would kill oblique-banded leaf roller worms that orawled over it •— Burtner (98). At Gresham, Oreg., various DDT inseotioides applied on small plots and fields involving some 250 acres of raspberries gave practically 99 percent control of oblique-banded leaf roller with no apparent ctrsrs to bees or other beneficial insects. Insecticides tested were as follows: (1) If percent DDT dust, one application 2 weeks before blossoming period; (2) Gesarol A-20, 2 pounds per 100 gallons, one -124- application 2 weeks before blossoming period* (3) 5 percent DDT in oil, 2 quarts per 100 gallons, one application 2 weeks before blossoming period.— Gray and Sohuh (189) . Argyrotaenla mar i ana (Fern.), the gray-banded leaf roller In a field teat 16 ounoes of DDT per 100 imperial gallons of water gave control approximately equal to that obtained with 5 pounds of lead arsenate •—Ross (306 ) • Cnephasia longana (Haw.), the strawberry fruitworm Gesarol A-5 dust, applied in May with a hand duster to 120 newly planted filbert trees (l£ acres) in the Willamette Valley, gave prac- tically 100 percent control •—Thompson (346 ) • Unidentified Lepidoptera Lejjidopterous caterpillars in an alfalfa field treated with a 3- percent DDT dust at the rate of approximately 28 pounds per aore appear- ed to have been killed,— Mi ohelbacher et al • (257). HYMENOPTERA Apidae Apis mellifera L«, the honeybee DDT has been found to be highly toxic to bees, both as a contact insecticide and as a stomach poison. If !JDT ever comes into general use as an insecticide, it conceivably might upset the balance of natural con- ditions by destroying the pollinators that produce many of our food orops. —Anon. (43) . See Arohips rosaoeana (Harr.) •— Burtner (99) • after an application of a DDT spray to sweet grapes (New York Muscats), wasps, bees, and Japanese beetles disappeared as if by magic —Bromley (96). Small cottkn plants were dusted with 3-peroent DDT dust (A-3) at the rate of 26 to 30 pounds per acre. Honeybees usually flew directly to freshly opened flowers and therefore usually did not alight on dust- ed surfaces; the feir bees that did orawl over the braots and corolla into the flower showed little or no apparent effeot of the inseotioide. —Smith (324). -125- « Unwanted honeybee colonies were eradicated slowly by 20 percent DDT (Gesarol A-20) ♦ Three percent DDT was ineffective when it was blown into oolony entrances*— TTolfenbarger et al. (379 ) • To avoid killing bees, open blossoms should not be sprayed with Gesarol, although its contact action against tees is less than against flies, beetles, and other pests.— Kobel (259) . Bees were abundant in an alfalfa field treated with a 3-percent DDT dust at the rate of approximately 28 pounds per acre and were not perceptibly injured.— Mi chelbaoher et al. (257) . Careful examination of the gound under hairy vetch at Oregon City, Oreg., disclosed that 5-percent DDT dust had killed insects of several species. Ho dead bees were found and no decrease was noted in the number of honeybees that were swept from hairy vetch dusted with DDT. — Rockwood and Reeher (303) • Individual honeybees placed on sheets of paper dusted with 1 per- cent of DDT in kaolin and covered with a beaker were totally paralyzed in 19 minutes and killed in 110 to 130 minutes.— Sen (311). It is not yet known just how serious a menace DDT spray residues on fruit trees and cover crops in orchards will be to honeybees, but experiments during 1944 showed that, although the bees were readily killed when confined in cages with sprayed material, the effect of visiting sprayed blossoms in the field may not be so serious as at first feared.— Ross (306) • DDT was applied to raspberries while in full bloom. Bees that worked the sprayed flowers were caged and compared with those taken far away from the area. The bees from ifoe sprayed areas appeared to live just as long as those from the unsprayed sections. In other experi- ments DDT was toxic to bees confined in quarters sprayed with the in- sect! oide»— Burtner (98). See Unidentified thrips.— Anon. (49). Formicidae Atta cephalotes (!••)» the couahi ant In a laboratory experiment in British Guiana 7 specimens of the soldier caste of Atta cephalotes were placed in a glass container the floor of which had been dusted with DDT. Alongside them was placed a suitable control experiment consisting of soldier ants from the same nest. Two hours later all the ants in contact with the insecticide were obviously affected, the usual tremulous movements in the limbs and their lack of coordination in locomotion being evident; 6 hours later the -126- affeoted ants were in a moribund condition, being on their baoks and in- capable of loo emotion although movements of the legs, antennae, and mouth parts oocurred occasionally; and after 24 hours all the ants were dead* The ants in the control remained unaffected throughout the test period*— J. (225). Camponotus hercuieanus pennsylvanicus (Deg*), the black carpenter ant Carpenter ants in poroh columns and in the hollow center of maple trees were eliminated with 5-peroent DDT dust*— H* J* Agr* Expt* Sta* (276). Camponotus spp*, carpenter ant In the Superior National Forest in Minnesota 17 log cabins were sprayed with 1- and 5- percent solutions of DDT in kerosene* Satis- factory control was obtained with a 5-peroent solution*— Craighead and Brown (125)* Irldomyrmex humilis Mayr, the Argentine ant A kerosene spray containing 5 peroent of DDT is extremely toxio to Argentine ants and has been successfully used around the casings of doors and windows of masonry buildings* The ordinary frame house, however, provides many entrances for this insect; under these conditions, stan- dard Argentine ant poisons plaoed around the outside of the house are far more effective than an attempt to treat all the interior*— Freeborn (160)* Lasius nlger alienus americanus Bnery, the cornfield ant Three applications at 4- to 8-day intervals of a 5-percent DDT dust (a small pinch per nest) failed to give complete control, although the number of nests was reduced by about four-fifths*— Ross (506 ) * Monomorium pharaonis (L*) , the Pharaoh ant A field test with 1 peroent of DDT in kerosene was disappointing* A further trial in which the concentration was 5 peroent and the walls were sprayed to leave about 100 mg* of DDT per square foot aohieved a very great reduction in infestation*— Buxton (100 ) . Solenopsis molesta (Say), the thief ant An ant (presumably the thief ant) attacking beets was killed and driven away by one treatment of Gesarol A-3 dust*— Parker (287 ) • -127- Thief ants in a bakery were eliminated "by the use of a 3-peroent DDT dust.— N. J. Agr. Expt. Sta. (275) . Tet ram prima caespitum (L.) , the pavement ant A S -percent IDT dust was ef fective.— Baseman (203) • Pavement ants attacking insulation of houses were destroyed by painting sills and surrounding structures with 3 percent of DDT in kero- sene.— F« J* Agr. Expt. Sta. (275) * Wasmannia auropunotata (Soger) , the little fire ant In preliminary tests with DDT favorable results were obtained in the control of the little fire ant on citrus trees in Florida.— Baker and Porter (81) • Unidentified species A very heavy infestation of ants (Formica sp.) was tunneling in the soil of some flats in a greenhouse and bringing tomato seed to the sur- face. Three percent of DDT in talc was applied to the flats and beneath the bench on which they were placed. No live ants were found 18 hours later. A few dead ants were found by digging in the flats.— Fletcher ( 155) r DDT is a contact poison to Formicides .— Domenjos (135 ) . Examination of the ground under hairy vetch at Oregon City, Or eg., disclosed that 5-percent DDT dust had killed ants.— Rockwood and Reeher (303). Sphecldae Mud-dauber wasps were quickly killed when they walked over wi. 3 screens treated with water suspensions of DDT in the form of Gesarol A-20 (0.8 pound in 100 gallons) .—Fluke and Pond (157) • Diprionidae Diprion frutetorum (F.) , an imported pine sawf ly Heodiprion leoontei (Fitch), the red-headed pine sawfly Complete control of both species was obtained with 2 pounds of DDT in 2 gallons of oil per acre. In treatments applied from an airplane against the red-headed pine sawfly, the spray was mixed at the rate of DDT 1 pound, oyclohexanene 1 pint, and a horticultural spray base heavy oil about 7 pints (enough to equal 1 gallon of mixed spray) • Against -128- the imported pine sawfly 1 l/2 pints of xylene were substituted for the 1 pint of cyclohexanone and the solution seemed perfectly satisfactory* — Dowden _et al • (136) • Complete control of the red-headed pine sawfly in a red pine plan- tation in northern Hew York was obtained by applying 2 1/2 pounds of DDT per acre. On the fringes of this sprayed area, where the spray drifted, complete control was obtained with a dosage believed to be not more than 1 pound of DDT in 1 gallon of liquid per acre*-- Craighead and Brown ( 125 ) • Trichogrammatldae Tricho gramma ep. See Diatraea saccharalis .— - Ingram et al* ( 222 ) . Vespidae Vespula arenaria F* A small quantity of Gesarol A-3 dust (3 percent DDT) was applied with an insecticide puffer to the exit holes of two active wasps' nests under the eaves of two neighboring garages at Westboro, Ont* No wasps were seen around the nest the next day and none issued from the nests when disturbed* The nests were cut down on the second day and found to oontain numerous living larvae and pupae and a few adults which were unable to fly* The wasps had apparently got the dust on their bodies while passing in and out of the nests and most of them after leaving had been unable to return.— Ross (306) • Unidentified wasps See Apli mell if era .— Bromley (96). DIPTERA inthomyiidae Fannla oanioularls (L*), the little housefly Same as for Musca domestics . ■— Ross ( 306 ) • Hylemya antiqua (Mg.), the onion maggot Gesapon No. 18, 1 gallon (approx. 8 oz. of DDT) per 100 imperial gallons of water was applied to seedling onions at the rate of 1 gallon per 120 feet of row. One series of plots vras treated on May 30, and a seoond series on May 30 and June 2. Results to June 30 were as follows: One application, 21 seedlings dead, 251 living, seedling mortality 8.3 percent; two applications, 46 dead, 290 living, mortality 15.3 percent; -129- oheck, 166 dead, 468 living, mortality 35.4 percent.— Ross (306 ) . Hylemya brassicae (Bouohe), the eabbage maggot These flies are controlled by watering each plant with 100 cc. of 1 percent Guesapon at the time they are set out*-- Geigy Colour Co. (166 ) . The cabbage maggot was not controlled by eight applications of 5 peroent DDT in light summer spray oil, average about l/2 gallon per acre, made by hand atomizer from June 6 to August 1.— Gray ( 188 ) . Dusts were applied from shaker cans at the rate of 20 pounds per acre. Applications were made before egg deposition by adults, and 11 days later the DDT dusts (2 and 4 percent) gave only slightly better re- sults than the checks. Calomel (4 percent) gave 96.4 percent reduction of the maggot population.— N. J. Agr. Erpt. Sta. (275 ). Hylemya floralis , radish fly Same as for H. brassieae.— Geigy Colour Co. (166) • Calliphoridae Calliphora vomitoria (L.) ■ ■ ■ ■ ■ ■ ii it. DDT is a contact poison.— Domenjo z (135 ) . Luoilla (« Phaenioia ) sericata (Meig.), greenbottle fly Laboratory tests showed than an emulsion containing 0.5 percent of DDT was toxic to laboratory-bred flies dipped in it. Welsh mountain sheep dipped in a bath containing C 3786 peroent of DDT remained free from strike for 42 days. The effectiveness of the dip lies in its direct action on the blowfly. Tests in which gravid females of L. sericata were kept in contact with the fleece of a DDT-dipped sheep showed €hat even 5 weeks after dipping 30-60 seconds' contact was sufficient to have a toxic effeot on the flies.— Cragg ( 124 ) . Luoilia caesar (L«) Same as for Masoa domestioa .- Ross (306 ) • Chironomida© Fhlebotomus spp., sand flies In Panama two tests were made in whioh houses were sprayed inside -130- and out -with a 2«5-percent solution of DDT in kerosene, but in both cases the tests were interrupted after a short time. In one house no sand flies were seen or reported 4 and 8 days after the spraying; in the other house, no sand flies were seen or no bites reoeived for 4 or 5 days.— Gorgas Memorial Laboratory (182 ) « Culicidae Aedes aegypti (L.), the yellow-fever mosquito Pieces of filter paper were treated with a range of doses of pure DDT, in a volatile solvent, so that the surface presented to test insects was dry; all insects were exposed at the same temperature and for the same period. The lethal dose for Aedes aegypti was 0,001 rng. of pure DDT per square centimeter,— Buxton (10*0") T~ DDT is promising for mosquitoes.— Annand (74), Gammexane £benzene hexachloride] scattered at the rate of 1/2 pound per acre killed 97 percent of the larvae in 2 days and 100 peroent in 3 days, as compared with kills of 43 percent in 2 days and 97 percent in 3 days with the same amount of DDT.— Anon. (52), Aedes sollioitans (Wlk.), the salt-marsh mosquito Under laboratory conditions colloidal solutions of DDT show very high toxioity to larvae of A. sollioitans and Culex pipiens L. but low toxicity to pupae of the same species. The toxicity to pupae can be materially increased by incorporating DDT into a mosquito oil emulsion. In dust form DDT proved ineffective against pupae and of considerably lower toxioity to larvae of subsurface-feeding species than it did in either an oil emulsion or colloidal solution. Toxicity to larvae can be increased by the use of certain solvents for incorporating the DDT into the dust. Under field conditions DDT dusts were practically ineffective against pupae, only of moderate toxicity to larvae of sub surf ace- feeding species, but highly toxic to larvae of surface-feeding species. As an oil emulsion, DDT gave effective control of both larvae and pupae in certain breeding places and poor control in other places, especially where pollution was present,— Ginsburg (178). Dilutions of 1 part DDT to 50,000,000 parts of water were very toxic to larvae of Aedes soliicitans and Culex pipiens in the labora- tory. Toxicity to pupae of 1 the same species was low. In the field, DDT preparations usually did not last any longer than mosquito oil applied under similar conditions, and were even less effective against pupae than in the laboratory. However, DDT preparations were more effec- tive against anopheline larvae than against subsurface-feeding larvae. Baulsion 50-D, applied at the rate of 50 to 70 gallons per aore, gave 100 peroent kill of anopheline larvae and lasted for 8 days. In general. -131- on subsurface-feeding larvae it appeared that DDT -was most toxic "when applied in colloidal dispersion, less toxic when applied in oil emul- sions, and least toxic when applied as dusts*— N* J. Agr. Expt. Sta. (276). Aedes vexans (Mg.) An emulsion of DDT (64 percent kerosene containing 2 percent of DDT, 34 percent water, and 0.5 percent sodium lauryl sulfate) applied at the rate of 7 gallons per acre [equivalent to 1*16 pounds DDT] to a woodland pool gave 90-95 percent control and the effectiveness last- ed 4 weeks.— Ginsburg (178 ) . Anopheles albiroanus Wied* In Panama over 200 tests with heavy dosages of DDT applied either as floatable dusts or in oils on the main types of mosquito breeding areas were effective for 2 to 6 weeks in heavy growths of Jussiaea , but only from 2 to 4 weeks in the more open Naias * Long lasting effects depend upon the protection of ihe floating dust or oil film* Under river margin conditions, DDT remained effective for a maximum of only 6 weeks under the most favorable conditions* Dosages of as little as 0*02 pound of DDT per acre in dust and 0*01 pound per acre in oils or emulsion gave perfeot to near perfeot kills of anopheline larvae in 24 hours* In the use of oils, it was found most satisfactory to use only enough oil to cover the area to be treated* Thus 0*05 to 0*025 pound of DDT in 1 to 4 pints of used crankcase oil per acre gave better kill- ing results than the same amounts of DDT in larger quantities of oil* An emulsion concentrate, when mixed with water and applied at the rate to give about 0*02 pound of 13DT per acre, gave perfect to near perfeot 24-hour kills of both anopheline and culicine larvae. This concentrate is more difficult to apply and, in concentrations as high as 200 ml. per acre, is quite lethal to fish* Comparative tests of paris green-talc and DDT-fcalo dusts indicated that the flDT dust was 5 to 10 times as toxic to anopheline larvae as the paris green dust. DDT dusts or oils, unless used in very heavy doses, were ineffective in controlling culi- cine larvae. DDT in emulsion was equally effective against culicines and anophelines* Other tests to control adult mosquitoes were also con- ducted. DDT in oil was applied by hand sprayers to the ground in jungle areas* All mosquitoes disappeared for 1 to 2 days in the quarter- to half-acre treated plots. Tests in an open orchard killed mosquitoes but infiltration was so rapid that biting rates soon returned to normal* Five liters of a 5-percent DDT solution in kerosene, applied with a knapsack sprayer, gave nearly complete kill of mosquitoes on a 1-aore plot in an open cacao plantation. Checks 48 hours later showed oomplete returns to normal mosquito populations.— Gorgas Memorial Laboratory (182) « -132- Anopheles crucians Wied* Same as for Aedes sollicitans. — Ginsburg ( 178 ) ■ Anopheles funestus Giles A dosage of only 0.10 cc. per square yard of a Diesel oil solu- tion containing 5 percent of pure DDT killed all larvae, and continued to kill for 4 days. This dose is extremely small, corresponds to 24 grams or 0.8 ounce per acre, a figure well below the conventional 2 to 4 ounces, even allowing for the fact that pure p,p f -DDT was used. Even more remarkable, a tenth of this dose (0*01 cc. per square yard, or 0.08 ounce per acre) killed all larvae but had no lasting effect.— Buxton (100) • Anopheles maculipennis Mg« Even extremely low doses of DDT, 50 mg* per square meter (10.8 sq* ft*), have some effect on mosquitoes although this is very temporary. With doses of 200 mg* per square meter or more the treated surface re- mains lethal to the maculipennis group for 10 weeks* Higher doses give a slightly prolonged effect which is not in direct proportion to the amount applied* In practioe a dose of 500 mg* per square meter should be aimed at and it should be considered to be effective for 8 weeks*— Buxton (100 ) • Anopheles quadrimaoulatus Say, the common malaria mosquito Up to 200 adults were found resting in 7 by 9 foot wall tents in a summer oamp near Marcellus, N. J* Additional adults were continually emerging from a large breeding area in a nearby lake. Groups of tents were treated with the following; 3, 1, or 0*5 percent of DDT in kero- sene, DDT emulsion diluted 1 to 4, DDT emulsion diluted 1 to 9*3, DDT dust (talc), N. J. Pyrethrum Larvicide diluted 1 to 10, and kerosene. The DDT emulsion contained 66 percent of kerosene, 2 peroent of DDT, and 0*5 peroent of sodium lauryl sulfate. A single thorough application was made with a knapsack sprayer or hand duster* Some tents were spray- ed with a small power sprayer* DDT-sprayed tents were almost entire- ly free of resting adults for the 3 l/2-week test period, as compared with 2 days* protection with N. J* Pyrethrum Larvicide. DDT dust showed little effectiveness* Kerosene apparently had some repellent effect* — Hansens (201) * Two formulas for DDT emulsion concentrates and detailed instruc- tions for spraying houses for the control of malaria mosquitoes are given. The summer formula contains 35 peroent of DDT in xylene and Triton X-100 and the winter formula 20 peroent of DDT* For use these concentrates are mixed with water in the ratio of 1:13 and 1:7, re- spectively, to give a spray containing 25 mg* of DDT per milliliter. -133- An application of 4 ml. of this spray per square foot remains effec- tive for 3 to 5 months.— U. S. Publio Health Service (354). A 3-percent DDT dust had little effect against adults hut as little as 0.6 percent of DDT in kerosene kept tents free of adult6 for the 3 l/2-week test period. DDT-oil emulsion destroyed the orig- inal mosquito population in the treated area, but mosquitoes coming into the area were able to bite. Therefore, DDT is not efficient foi temporary outdoor protection. Field and laboratory tests were made against larvae of Culex pipiens , Aedes sollioitans , and Anopheles quadrimaculatus with dusts, emulsions, alcoholic colloidal dispersions, and kerosene solutions. The dust diluents used were talc and pyro- phyllite. The most used emulsion (50-D) contained 66 percent of kero- sene, 2 percent of DDT, 0.6 percent of sodium lauryl sulfate, and the rest water, and was diluted 1 to 10 with water for field application. — N. J. Agr. Bxpt. Sta. (275) . A new device for mosquito extermination oonsists of a bottle con- taining a small amount of TJOT in oil, which is partly buried in the soil where hatching is likely. The bottle has an opening just above ground level. When the flood water arises to this opening, the oil floats out and spreads a thin, deadly film to kill newly hatched mosquitoes as they come to the surface.— St ener son (337 ). Tests against adults were made in a Peet-Grady chamber using 6 ml. of spray and a 2 l/2-minute exposure. The laboratory tests showed that 1 percent of DDT in deodorised kerosene gave only a 57 percent knock- down but a 24-hour mortality of 100 percent. A 1-percent Pyrethrol 20 spray gave excellent knock-down (97 percent) and kill (94 percent). One percent of a 20*peroent DDT and 80-percent Thanite combination gave re- sults which compared closely with the pyrethrum, namely, 92 percent knock-down and 96 percent kill; whereas the corresponding results for a spray made up of 1 percent of a 40-pereent DDT and 60-percent Thanite combination were 86 peroent knock-down and 99 percent kill. The poor knock-down produced by DDT alone in -fee laboratory led the investigators to restrict field tests to combinations of DDT and Thanite, using py- rethrum as a standard spray for comparison. The results obtained from nine replications were as follows! 1.5 percent Pyrethrol 20, 88 peroent knook-down and 73 percent kill; 1«5 peroent of the 20-peroent IDT and 80-peroent Thanite combination, 86 peroent knock-down and 94 peroent kill; 1.5 peroent of ttie 40-percent DDT and 60-percent Thanite combi- nation, 84 percent knock-down and 98 percent kill. Both the DDT-Thanite •prays gave good results, but the 20-80 combination appears to be particularly promising.— Rioe et al. (301) • -134- The early history of DDT as a mosquito control agent has been sketched by Stage (330 ) . In laboratory tests a dosage equivalent to only 1 pound of DDT to 250 acres of water surface was completely effec- tive against full-grown larvae of Anopheles quadrimaculatus Say. DDT was toxic as a dust to 62 percent of these larvae when applied at the rate of 0.0001 pound per acre. As a suspension at 0.01 p.p.m., it gave practically 100 percent mortality in 48 hours, being more than 100 times as toxic as phenothiazine. In the field a spectacular kill of mosquito larvae was observed when a mist spray containing 9.5 quarts of 5 percent DDT in fuel oil was dispersed from a decontamination cylinder over nearly 2 aores of Pontederia swamp. This application, at the rate of 0.15 pound of DDT per acre, gave perfect control over the entire swamp area} i»e., for a distance of 600 feet from the point of application. Although DDT is stable and long-lasting, certain fao- tor3 limit the duration of its residual action when it is applied in dusts to water surfaces. Research conducted in unprotected breeding areas showed that wave action, wind, and water movements cause shift- ing of surface films of DDT dust, wito. a consequent loss in effect shortly after application* In quiet pools where the vegetation is dense, effective control of anophellne breeding has been obtained for a period of 4 to 8 weeks when DDT dusts have been applied at the rate of 1 to 2 pounds of DDT per acre. Very little progress has been made in determining the action of dusts. Because of its extreme toxicity when taken internally and because of the feeding habits of the larvae, it is presumed that DDT in a dust kills primarily as a stomach poison. Tests with petroleum oil solutions at remarkably low dosages have demonstrated satisfactory control of Anopheles larvae. The effective amount of DDT in petroleum oils is essentially the same as when applied in dust form. As little as 1 quart of oil per aore of water surfaoe gives high kills when reinforced with 5 percent of DDT. In fact, the size of the dosage is limited greatly when. DDT is applied with exist- ing spray equipment because of the difficulty of spreading the email volume of larvicide evenly over the water. Flowing water has been successfully treated with DDT by means of drip cans. The usefulness of DDT as a larvicide is not limited to anophelines. It is also very effective against culicine mosquitoes. In suspensions, dosages of 1 p.p.ro., or higher, show residual toxicity to species breeding in rain barrels. In field applications suspensions and emulsions of DDT were more generally effective against the fresh-*water and salt-marsh culi- oines than was DDT as a surface application in dusts or oil solution. Dosages as low as 0.05 p.p.nu were effective against Aedes ta eni orhynohu s Wied., A. sollicitans (Walk.), A. aegypti (L»), Psorophora confinnis L. Arr., P. ciliata F., and Cul"ex quinquefasciatus Say. 0*n the basis of this work, Busman and Longcoy in 1943 designed spray equipment for light planes which dispersed a 5- to 10-percent solution of DDT in fuel -135- oil at the rate of 2 quarts per aore. Exoellent control of adult Aedes taeniorhynchus in densely wooded areas was obtained by this means. Sucoess was also attained in 1943 by the use of a 20-percent DDT solu- tion from exhaust equipment installed on a Cub plane* A* W. Lindquist aided in additional tests conducted by the Army in the Panama Canal Zone in April, 1944, and demonstrated a 98 to 100 percent oontrol of Anopheles alb Im ams Wied., and Mansonia fasoiolata L. Arr., "rtien 2 quarts of a 10-percent DDT solution were applied by a Eusman-Longcoy spray unit installed on a Piper Cub plane* Some details of operational planning for the application of Wtt residual spray to the interiors of 375,000 houses in 110 endemio malarious counties of 13 southern States this year have been presented. Procedures followed and formula, ma- terial, and equipment being used in current operations are preliminary and subject to further refinement and basic alteration as a result of experience gained from routine project operation and field experimental work. The concentrate solution, whioh is carried by the hand sprayer crew in an Army-type 5-gallon gasoline can, is composed of 35 percent DDT in xylene, plus a small quantity of emulsifier. This solution is readily miscible in water. The emulsion has a breaking time of 30 minutes but this does not occur while the sprayer is agitated as in normal usage. Other comparative advantages of an aqueous emulsion are freedom from fire hazard and reduced solvent action and spotting on interior finishes, clothing, and other fabrics. An emulsion applica- tion rate of 4 ml. per square foot will be used. "While lower quanti- ties can be applied on experimental activities, experience indicates that most laborers apply at least 4 ml. per square foot to obtain visible wetting of the surface. Under these conditions, a DDT applica- tion rate of 100 mg» per square foot dictates the selection of a 2^- percent emulsion strength.— Henderson (206) . DDT insecticides are so muph more effective than previous weapons against malaria mosquitoes that for the first time iiiere is a practical hope for eradicating that disease from this country • "For the control of mosquito larvae DDT as a dust is no more use- ful than paris green. At present, with a price differential of well over 50 cents a pound, it would seem inadvisable even to experiment with DDT as a dust larvioide. The chief value of the spray is that extremely small quantities may be as effective as the application of large amounts of fuel oil. A 5 percent dilution in kerosene or diesel oil is excellent. The ideal treatment recommended for this dilution is 1 to 2 quarts per acre, as contrasted with 18 to 20 gallons of fuel- oil dispersal. These figures give some idea of the minute quantity that should be used." -136- "Contrary to reports from some of the earlier experiments however, rflTT has no magic power of spreading itself over water surfaces. In dispersing the small amount of material required, one must make sure that it is introduced over the entire surface, particularly if rafts and booms of floatage will cut its access to the sheltered areas where breeding may be intense. In dispersing the 5-percent kerosene mixture, one may well apply the material from the windward side and allow it to drift over the breeding area* In order to increase the coverage and to cut do-wn the care which is necessary in applying minute amounts with kerosene as a carrier, considerable work has been done with emulsions. By using a quick-breaking emulsion, such as is made with phthalic glyceryl alkyd resin, one can apply the material on the acre basis, figuring at the rate of about l/lO pound of DDT per acre. If, however, a tight emulsion is produced, as with polyethylene emulsifier, the dosage should be figured roughly on a voluroetrio basis so that the DDT will not exceed 1 part in 10 million. Any greater concentration will certainly be detri- mental to fish. The addition of DDT to irrigation water at its source has proved particularly disappointing." A residual spray applied at the rate of 100 to 200 milligrams per square foot will effectively kill all adult mosquitoes that come to rest on the treated walls for a period of at least 3 months and possibly longer.— Freeborn (160) • Same as Aedes sollicitans .— Ginsburg ( 178 ) * DDT is more toxic to mosquito larvae than any agent heretofore known. Consequently, it can be used in small amounts with resultant saving in time and effort. Sprayed on interior surfaces IDT remains as a residue which will kill insects lighting on the treated areas for several months. Thus, by spraying the habitations of native carriers, a long-lasting means is provided to destroy infected mosquitoes which might convey malarial parasites to troops. DDT, just recently available in quantity for mosquito control, is a revolutionary new weapon in the fight against malaria.— Simmons (519 ) • Anopheles triannulatus (N. and P.) Same as for Anopheles albimanus .— Gorgas Memorial Laboratory (182 ) • Anopheles spp. For the control of adults with residual sprays a dosage of 100 mg. of DDT per square foot should be aimed at. Another promising use of the film effect is the impregnation of wide-meshed bed nets, which would probably make them effective barriers against small species of Anopheles, and also against such little pests as Fhlebotomus. -137- For the control of mosquito larvae a standard dosage for many types of water is 1 to 2 imperial quarts per acre of a 5-percent (w/v) solution of DDT in an oil of good spreading power. It is often very difficult to put down so small a volume on an aore, even using a fine nozzle and low pressure on the sprayer: it may be preferable to double or treble the volume of oil, using the same amount of DDT.— Buxton ( 100) • DDT is a contact poison to Anopheles .- Domenjoz (135 ). The methoxy and the ethoxy analogs of DDT were found about equally effective against mosquito larvae (Culex guinquefasciatus ) ; concentra- tions of 0.03 to 0.04 p.p.m. in tap water killed half of the larvae in 20 hours. The n-propoxy analog at 0.4 p.p.m. gave about a 50 percent kill while the n-butoxy analog at 4 p.p.ro. gave a negligible kill.— Prill _et al. (297 ) . Culex pipiens L., the northern house mosquito Same as for Aedes s o 1 1 i o i t ans . — N • J. Agr. Expt. Sta. (275 ) j Ginsburg ( 178 ). Culex salinarius Coq. Culex territans Walk, (s restuans Theob.) Sane as Aedes sollici tans .—Ginsburg (178 )» also N. J. Agr. Expt. Sta. (275) . Unidentified moBqultoes The abundance of unidentified mosquitoes was noticeably reduced in a number of plots sprayed with IDT.— Craighead and Brown (125 ) . Adult mosquitoes and houseflies were killed by applying a 5-peroent DDT solution in kerosene to walls, doors, and screens of buildings by means of power paint sprayers, hand spray guns, and paint brushes. The men wore protective masks. The insectioide did not give immediate re- sults but after several days medical officers were convinced of its effectiveness. Areas have to be resprayed about every month or 6 weeks. — Farr (149); Anon. (19). A joint statement of policy by the U. S. Army and the U. S. Publio Health Service, adopted March 31, 1945, called for the distribution of DDT from airoraft for large-scale area control of mosquitoes in mili- tary and adjacent areas in the United States to be limited to projects conducted with due regard to its possible effects on beneficial insects and all forms of plant and animal life, and in accordance with safeguards -138- established by the Surgeons General of the two services.— U. S. Army and U. S. P. H. S. (351). The use of DDT by troops during an invasion to control mosquitoes, flies, and other insect vectors of diseases is discussed • — Logue and O'Connell (248). Kaolin containing 1 percent of DDT was dusted on sheets of paper on which mosquitoes were separately placed and covered with a beaker. The time, in minutes, to partial paralysis was 20, to total paralysis 60 to 70, and to death 170-190. Tflhen 1 percent of DDT in kerosene-tung oil mixture was spread on water it killed mosquito larvae in 40 to 50 minutes*— Sen (311 ) ♦ Itonididae ftphidoletes sp* Cucumbers heavily infested with aphids were sprayed with 16 ounces of DDT per 100 imperial gallons of water, both in powder suspension and in Velsicol emulsion, and counts showed no apparent reduction in tie large numbers of Aphidoletes larvae present*— Ross (506 ) • Diarthronomyia hypogaea (Loew) , the chrysanthemum gall midge Several hundred cuttings of 15 to 20 varieties and small plots of 2 varieties were sprayed* Cuttings were sprayed twice at 10-day inter- vals and plants were sprayed four times at 5- to 7-day intervals. The spray contained 5 pounds of a 20 percent DDT-pyrophyllite dust plus 0.5 peroent Vatsol OS in 100 gallons. On cuttings after treatment, 0.64 new gall per plant appeared as oompared with 24.2 galls on untreated plants. Larvae and pupae in galls were not affected and newly emerged adults lived long enough to lay eggs. On newly set plants excellent control was obtained and no plant injury was apparent after 10 weeks. — N. J. Agr. Expt. Sta. (275 ). Monarthropalpus buxi (Lab.), the boxwood leaf miner This pest was readily controlled with DDT (0.1 to 1 peroent) applied as an emulsion in small-scale tests.— Craighead and Brown ( 125 ) • ltaseidae Glossina spp. Glossina spp. are readily killed by traces of DDT on oloth. This operas up great possibilities of control, by treating bait animals with -139- DDT emulsions, or by impregnating clothing or sacking soreens*- Buxton (100), Musoa domeatloa L*, the housefly A 2-peroent solution of DDT in deodorised kerosene sprayed on the walls and ceiling of a poultry killing room gave 100-percent mortality of flies in the room up to a month after treatment. Over a 6-week period only 8 percent as many flies were observed within a poultry lay- ing house, the walls and ceiling of which had been sprayed with a 3- percent solution of DDT in deodorised kerosene, as were seen in an un- sprayed house.— Wolf enbarger _et al . (379 ) • See also under Themira putris *—-ffolf enbarger et al * (379 ) • See Anopheles spp*— Farr (149) ; Anon* (19) • In one test a 0*01-percent solution of Gammexane killed 73 percent of a known number of flies, whereas a 0*02-percent DDT solution killed only 51 percent*-- Anon* (52)* DDT may be sprayed over wide areas from the air* In Sweden farm and grain areas have been treated, this way throughout the year at inter- vals of several months and dairy farms have been practically fly-free during the entire summer. Increase in milk production was noted. In the future there may be derived an effective insecticide from the com- bination of pyrethrum (or derris) and DDT, in which the pyrethrum will have the rapid and the DDT the lethal action*— Ahlb erg and Mathlein (69). Unpublished figures by Parkin and Green of the Department of Scientific and Industrial Research [Great Britain] show that 0.05 per- cent of DDT plus 0.02 percent of pyrethrins is barely satisfactory against flies. A mixture containing 0.10 percent of DDT and 0.03 percent of pyrethrins, applied with hand sprayers at the rate of 26 co. per 1,000 cubio feet in rooms and army huts at about 24 C. gave a high knock-down and killed all the flies. These workers have also shown that mixtures of DDT and pyrethrum in kerosene can be stored under suitable conditions for at least 17 months at 27.5°C. without marked deterioration. The present British official recommendation for a general spray for killing adult flies and mosquitoes is 0.07 percent pyrethrins (or more if available) j or 0.05 percent pyrethrins + 0.3 percent DDT; or 0.03 percent pyrethrins +0.5 percent DDT. The per- centage of DDT refers to the pure para-para-prime substance. The dosage is 10 cc. per 1,000 cubic feet (l fluid ounce per 3,000 cubic feet), subject to considerable latitude, if used in rather open huts. —Buxton (100) • -140- We can anticipate the use of DDT sprays on -walls and screens for gradual reductions of fly populations. If some formulations of such sprays are used on animals, they may be found rather slow in killing stable flies, horse flies, and deer flies. These kinds of flies may bite and fill with blood before they die from the effects of the sprays. For these important kinds of flies there would seem to be an oppor- tunity for inoluding in the new sprays a repellent that would drive away the flies during milking or for longer periods of time. Again, this involves more research if we are to get the correct answer. If repellents are used in spray mixtures, will they drive away the inseots during the period when tiie fly toxioant is most effective, thereby re- ducing the efficiency of a spray as a killer of horn flies and other flies on oattlo?~Dove (137) . Aocording to the U« 3, Army Medioal Department the DDT insecti- cides suitable for use in fly control are* (l) Insecticide, spray, DDT residual effect (5 percent DDT in kerosene), Quartermaster Stook No. 51-1-505} (2) inaeotioide, powder, louse (10 peroent DDT in pyro- phyllite), Quartermaster Stock No. 51-1-180 j (3) larvioide, DDT, powder, dusting (10 percent DDT in tale), Quartermaster Stook No. 61-L- 122» Use idie DDT insectioides as follows in pit latrines: Apply the spray at the rate of 1 quart for approximately 250 square feet to the walls of the pit, inside and outside the latrine box, and to all the walls, window screens, and screen doors of the enclosure. One application usually is sufficient for several months. Apply DDT resi- dual spray at the rate of 2 ounces per latrine box hole, or 10-percent DDT powder at the rate of 1 ounoe per hole %o the pit contents. Apply twice weekly until experience reveals how often application need be repeated. Residual spray may also have a plaoe in the field for treating ration dumps and dead bodies to control fly breeding. As little as 0.025 peroent of DDT in oil has been found effective in kill- ing maggots breeding in meat. The residual spray should kill both adult flies and larvae. Since the odor at times may be offensive, work is under way to find a satisfactory deodorant to incorporate in spray for this purpose.— Anon. (26) • For the oontrol of houseflies and stableflies apply DDT exaotly as for residual spraying for mosquitoes. The spraying of manure piles, the walls behind them, and the most obvious gathering plaoes in the stables will destroy numerous flies before they leave the breeding grounds. Fer household oontrol treat especially screens, door and window frames, shelves, the edges of pillars, and other areas that fly "spooks* indioate as habitual resting places.— Freeborn (160) . -141- When tested by the method described under Rhodnius sp. the lethal dose of pure DDT to adult Musca domestlca was 1.0 mg. per square centi- meter of surface.— Buxton ( lOO ) > When DDT was sprayed in barns of the Idaho Agricultural Experi- ment Station in September, the air was full of flies* In October when flies should have been their worst, the barns were as fly-free as they usually are in midwinter. The DDT was applied as a light spray, of about 1 percent strength, to walls, ceilings, doors, and windows.— Idaho Univ. Col. Agr. (221) . The methoxy, ethoxy, n-propoxy, and n-butoxy analogs of DDT were toxic to houseflies in dimTnishing degree"~in the order named. The methoxy analog exoels DDT in knook-down but does not equal it in kill* —Prill et al. (297) . DDT percentages evidently are not being increased in the aerosol, and Army authorities continued to depend on pyrethrum as the knock-down ingredient in fly and mosquito repellents, with sesame oil as the synergist and Freon-12 gas as the carrier. Yet DDT has been shown to increase the effectiveness of the formula considerably.— Stenerson (336 ) » In kerosene solution, varatridine was more toxic than cevadine to houseflies, and both these constituents of sabadilla were more toxic than DDT.— AIF (66) . Two days after the initial assault in Iwo Jima in the Pacific the island was sprayed with a DDT solution by airplane. In spite of the thousands of American dead and Japanese corpses on the island, the fly problem which was so great in former Pacific amphibious operations was pj-»otically nil. — Peaker (291) . A report of tests of a DDT-oil fog in the Salt River Valley, Ariz. The oil solution of DDT is not burned but made into a fog by feeding into a current of steam. Some of the oattle were driven through a oan- vas-oovered ohute, with the generator blowing fog over them. Some were simply enveloped in fog as they stood in an open corral. A blast was also turned into the barn. Almost at onoe lifeless hornflies and house- flies began to roll off the backs of the oattle. Flies rained down upon the floor of the barn and oontinued to fall for two days. For 2 days, also, the "fogged* cattle remained free of flies. Dr. Dietz said that from his experiments the residual effeot of DDT lasts for 14 days in the open air when application is by spray. Apparently the time is less when application is by fog, probably because the amount deposited is so much less.— Anon. (49). A water suspension of DDT gave excellent oontrol of flies in a dairy barn. One of the mixtures tested was, DDT (AK-20, containing 20 percent DDT) 10 pounds, blood albumin 6 ounoes, water 100 gallons.— Uiohelbaoher et al. (268). -142- A water suspension of DDT (1 pound per 100 gallons) is preferred for the control of flies in dairy barns because of the danger of the operator becoming thoroughly wet with a kerosene solution and hence poisoned when it is necessary to spray overhead .--Michelbacher ( 256 ) • A 10 percent DDT-pyrophyllite dust was applied in a dairy barn about 3 p.m. on July 25 by means of a hand duster; this was directly after the cattle had been brought in from out-of-doors. Immediately prior to application the floors were swept clean and most of the windows dosed. Within 15 to 20 minutes the flies were observed dropping to the floor, and by 4 p.m., which was milking time, no fly spray was needed before the cows could be milked. Approximately 3 to 4 flies per square foot of floor surface were killed the first day after the dusting, but the number rapidly diminished thereafter. On the third day the herdsman found it necessary to resume the applica- tion of a fly spray. A spray made by adding a 25 percent DOT self- emulsifying conoentrate to water (1:160) plus 1.4 pounds of blue vitriol per 100 gallons greatly reduced the number of flies in a hog barn.— Munro j3t _al. (271 ) • A small unscreened compartment containing a bull was sprayed with 3 percent IDT in kerosene. One hour after spraying all flies were dead or affected and for 9 days thereafter fly annoyance was at a minimum. A small unscreened stable was sprayed several times with 1.5 to 3 percent DDT in kerosene. A manure pile adjacent to the stable served as a constant source of reinf estation. Flies were eliminated from the stable for 1 day after treatment. They were present there- after in about the same numbers as before spraying. Three percent DDT in kerosene gave control of flies in chicken coops for about 3 weeks. In other tests 3 percent IDT in kerosene sprayed on the outside of the kitchen at the Merchant Marine rest home failed to give relief. Spray- ing the inside of a dairy barn feed house where flies congregated with 3 percent DDT in kerosene gave unsatisfactory control.— N. J. Agr. Sxpt • Sta . (275 ) . Two methods were used to control flies in barns in Minnesota. In one test all the screens were painted with 5 percent of DDT in kerosene. In the other tests water suspensions of Neocid A-5 or Neooid A-20 were sprayed on the walls and ceiling. Painting the screens killed large numbers of houseflies and stableflies, but the amount of surface treat- ed was too small to give satisfactory control. It was estimated that the population was reduced by 30-40 percent after the screens were treated. A water suspension of 2 percent of Neooid A-5 gave fair con- trol for about 1 month when applied to walls and ceiling as a coarse spray. Both a 1-percent and a 2-percent suspension of Neocid A-20 gave much better control, with the latter giving good results for 6-8 weeks. One barn with about 5,000 square feet of sprayed surface was kept free -143- of f lies all summer with two applications of 18 gall cms each of a 2-per- cant suspension of Neooid A-20#— Hodson (212 ) » Adult houseflies of both sexes, 5 days old, were sprayed under regular Peet-Grady test conditions with 0.2 percent of DDT in Deobase. DDT caused slight dissolution of fiber tracts and degeneration of nuclei both in the brain and in the fused thoracic ganglia, but in spite of its pronounced neurologic symptoms histological changes were relatively slight.— Hartzell (202) . Five percent of DDT in kerosene painted on a fly screen killed flies for more than 6 weeks. Where the sun shines on the screen it will last for 2 or 3 weeks. — Hutson ( 220 ) . DDT is a contact poison to Fu s ca domestica . — Domenjoz ( 135 ) • Preliminary tests were made of DDT in a solvent composed of 90 percent acetone and 10 percent Deobase by applying the spray directly to screen cages containing the flies. From the dosage-mortality curve so obtained, it was found that dilutions as low as 0.025 percent were quite effective against flies with regard to kill but were slow in knockdown. Sprays ranging from 5 percent to 0.2 percent of DDT gave complete knockdown in from 11 to 15 minutes. It was clear that DDT was slow in knockdown and that its knockdown could not be increased ma- terially by an increase in concentration of the DDT. On the basis of these results, three Deobase sprays were made up containing 0.2 percent of DDT to give a safe margin for practical use. Each spray contained a different paralytic agent to evaluate three common agent3 now on the market. Butyl carbitol thiooyanate was used at 0.75, bornyl thio- cyanoacetate at 1.2, and pyrethrins at 0.05 g. per 100 ml. of spray. These sprays were evaluated in the Peet-Grady chamber and in labora- tory rooms in which 300-500 flies had been liberated. The sprays were found to be almost equally effective, killing all the flies overnight. In the practical tests in rooms, knockdown required about 30 minutes, probably because of the high ceiling in the rooms used. Knockdown in the Peet-Grady chamber was very satisfactory in each case. A Deobase spray containing 0.2 percent of DDT was atomised into a Peet-Grady chamber at the rate of a fluid ounce per 1,000 cubic feet. Sheets of cellophane and cotton towels were placed on the floor of the chamber to catch the falling residue, and, after all the spray had settled out, the oellophane towels were removed and placed in glass cages containing about 100 flies each. The residue from a single spraying on oellophane (0.33 mg. per sq. ft.) killed 74 percent of the flies confined with it for 24 hours. Sheets held for 7 days before exposure to flies killed only 1 percent of the insects. Tie residue from three sprayings (l mg. per sq. ft.) killed 100 percent and 88 percent of the LIBRARY STATE PLANT BOARD -144- flies in the 1- and 7-day intervals after spraying. Six spray applica- tions (2 mg. per sq. ft.) produced a residue killing ail flies even after the 7-day interval. From these results it is quite evident that fly sprays containing 0.2 percent of DDT will leave a toxic residue when they settle out on nonabsorbent surfaces near or on the floor of a room. Spray residues on cotton towels were much less effective against flies. Six spray applications (2 mg. per sq. ft.) killed only 46 per- cent of the flies confined on the towels within the first day after spraying. Eighteen application (6 mg. per sq. ft.) killed 92 percent of the flies on immediate exposure and 89 percent 7 days after the spray was applied. These figures show that several applications of a fly spray containing DDT in a room will leave a toxic residue on nonporous surfaces on which it settles, but that toxic residues will not be built up on porous materials such as carpets, bedspreads, etc Several different types of DDT formulations were applied to nonabsorbent sur- faces to check the type of residue likely to be most effective against houseflies. In order of their effectiveneas, these compositions were a DDT solution in a nondrying oil, a 5-peroent dust (talc), an aqueous suspension of a wettable powder, a solution in acetone, and a 5-peroent solution in paste wax. The results seem to indicate that residues are effective in proportion to their ease of removal or low adhesivity to surfaces.-- Goddin and Swingle (179 ) . One percent of DDT in kaolin was dusted on sheets of paper on which insects were placed separately and covered with a beaker. The time in minutes, to partial paralysis was 6, to total paralysis 20, and to death 150-160.— Sen (311). The effect of a residual deposit of DDT on flies was investigated under practical conditions at the Central Experimental Farm, Ottawa, from September 7 to November 14, 1944. GNB-A-DDT (commercially pure DDT) was dissolved in a small quantity of benzene and diluted to 5, 4 and 3 percent with deodorized kero. ^ne. Walls and ceilings were spray- ed in (a) a milk room with 5 percent spray, (b) a dairy building with 4 percent, (c) a calf barn with 3 percent, and (d) a piggery with 3 percent. Control during the period of almost 10 weeks averaged 99 per- cent in the dairy, 96 percent in the piggery, 92 percent in the milk room, and 88 percent in the calf barn. The daily kill at one time reached approximately 30,000 in the piggery. The tests were terminat- ed by cold weather. Flies killed included Musca domestica L», St om oxys calcitrans L., Fannia canicularis L., Lu cilia caesar L., Vuscina stabulans Fall., and" a few other species in small numbers.— Ross (306 ) . Musoina stabulans (Fall.), the false stablefly Same as for Musoa domesti ca.— Ross (306 ) • bxphona irritans (L.), the hornfly See Musca domestica.— Anon. (49); Munro et al. (271) . -145- Storaoxys calcitrans (L.) , the stablefly An open milk shed, including the floor, was dusted thoroughly with a 3- percent DDT dust on September 18 and again 3 days later. Before dusting the flies were so numerous it was almost impossible to milk the cows as both cows and milkers were severely attacked. Three days after the second application only an occasional fly was observed. The legs of the cows were also Ousted with the 3-percent dust without any observable harmful effect. — Ewart ( 145 ) • See Mjsca domestica . — Dove (137 ); Freeborn ( 160) ; Munro et al. (271); N. J. Agr. Expt. Sta. (275); Ross"T|06) . Stomoxys spp. An extraordinary reduction of Stomoxys , in West Africa, followed the spraying of one cow out of a small herd of a dozen animals whioh were suffering very greatly.— Buxton (100 ) • Oestridae Hypoderma bovis (Dog.), the northern cattle grub Gesarol A spray 7.8 pounds (DDT 0.4 pound) per 100 imperial gallons of water sprayed on animals at 400 pounds pressure had little effect on warbles, killing only 5.5 percent as compared with 73.9 percent by a 5-percent rotenone mix at 250 pounds' pressure. — Ross (306). DDT is a contact poison. — Domenjoz (135). H. lineatum (De Vill.), the common cattle grub Same as for H. bovis .— Ross (306 ) . Psilidae Psila rosae (F.), the carrot rust fly In Switzerland the injury caused by the first generation of the carrot fly can be controlled by watering the carrot crop in mid-May with a 0.5 to 1.0 percent Guesapon emulsion at 4 liters per square meter. The control of the more serious second-generation injury can be achiev- ed by watering the crop with 2 percent Guesapon at 4 liters per square meter in mid-July.— Geigy Colour Co. (166). Gesarol A-3 (3 percent DDT) was dusted on the crowns of the plants at the rate of 1/2 pound per 100 feet of row. Three applications on July 13, 21, and 28, were made and the orop was lifted September 1. Little or no control resulted, the infestation being 29 percent in the -146- oheck and 24 percent for the Geaarol A-3 dust.— Ross (306) • One application of Gesarol A-3 dust at the rate of 0.5 pound per 100-foot row reduced the percentage of wormy carrots from 55 (in the cheok) to 12.— Morrison (266). Sepsidae Themira putris (L.) Samples containing l/l4 cubic foot of maggot-infested poultry droppings treated with 1-peroant solutions or suspensions of phenothia- *ine, TOT (Gesarol A-20), thiourea, and borax, yielded, respectively, 26, 28, 83, and 89 adult flies, whereas the corresponding number for the cheok was 238. Solutions or suspensions containing 0.3, 1.0, and 5.0 percent of the toxicants were used to treat similar samples of droppings. The average numbers of flies which emerged per sample from droppings treated with these three concentrations were as follows: Phenothiazine 23/ 5, and 5j DDT oil solution. 9, 3, 0; DDT water suspen- sion, 3, 30, and 19* Areas under turkey sun porches were treated with phenothiazine diluted It 5 with lime, and 1-peroent spray solutions or suspensions of borax, DDT (Gesarol A-20), and thiourea^ The average numbers of flies emerging per sample were 21, 18, 21, and 37, whereas 87 emerged from the control*— Wolfenbarger et al« (379 ) . Simuliidae Simullum spp., blaok flies The abundance of blaok flies was notioeably reduced in plots sprayed with IDT •—Craighead and Brown (126 ) • Syrphidae Sphaerophoria oylindrioa (Say) In laboratory tests there were no survivors in any DDT-treated cages after 24 hours* The DDT (Gesarol A-20) was added to water at the rate of 0*8 pound in 100 gallons. The test plant was plum foliage infested with aphids*- Fluke and Pond (167 ). Unidentified species Syrphid flies, eggs, and larvae were extremely abundant and active on rosy apple aphid colonies on opening buds in an untreated plot but were not apparent in a DDT-treated plot.— Cleveland (114) • -147- There appeared to be no appreciable mortality of syrphid larvae on aphid-infested cucumbers thoroughly sprayed with 16 ounces of DDT per 100 imperial gallons of water in powder suspension or Velsicol emulsion.— Ross (306 ) . Tabanidae Chrysops flavida Wied. Same as for Tab anus abactor • •— Okl a • Agr. Expt. Sta. ( 278 ) • Chrysops spp., deer flies The abundance of deer flies was noticeably reduced in a number of plots sprayed with DDT •--Craighead and Brown (125 ) . See Misoa domestica .— Dove (137 ) • Pangonla inolsa Wied. (g Esenbeckia incisuralis (Say)) Seme as for Tabanus abactor *— Okla. Agr. Expt. Sta. (278) • Tabanus abactor Philip JT. equal is Hine Aqueous sprays containing 5 percent of DDT applied to cattle gave repellency while wet. The flies began to die in 12 to 18 hours after feeding but much of the spray* a effectiveness was lost after 24 hours. Definite conclusions were not made due to high mortality in the checks. — Okla. Agr. Expt. Sta. (278 ) . See Musca domestioa .— Dove (137) • Tachinidae Spilographa electa (g Zonosemata electa (Say)), pepper maggot A 3-percent DDT dust and a spray containing 1 pound of DDT in 100 gallons of water were applied to peppers four times at weekly intervals after the first egg punotures were noted. The spray gave a reduction of 45 peroent in infested peppers and the dust gave 25 percent reduction. Adult 8 were noted walking over the insecticide deposit, but no dead flies were found in the plots.— N. J. Agr. Expt. Sta. (275). -148- Trypetidae Rhagoletis cerasl (L.), the cherry fruitfly Field experiments carried out in Switzerland in 1943, showed that it i6 possible by correct, biologically based spraying of cherry trees with 1 percent of Gesarol to combat this insect successfully even in highly infested areas. The spraying of the cherry trees should begin during the first days of June. A seoond treatment applied 14 to 16 days after the first will last until harvest. No separate treatment of the ground is neoessary.— - Wiesmann and Fenjves (575) . Rhagoletis cingulata (Loew), the cherry fruitfly Rhagoletis fausta (O.S.), the blaok cherry fruitfly Results obtained with DDT against the cherry fruitfly were promis- ing enough to warrant further tests.— Baker and Porter (81). Results of tests with DDT in Oregon in 1944 for the oontrol of the cherry fruitfly were far from favorable.— Childs (110 ) . Dusts containing 2 or 3 percent of DDT with sulfur, talc, and diatomaceous earth at 40 pounds per acre failed to give satisfactory control of the cherry fruitfly.— Childs and Robinson (ill) . In the laboratory the action of several DDT preparations on flies was slow, although some of the flies showed typical DDT symptoms within an hour after they were put in the cages. It required 80 or more hours to kill 50 percent of them. Two field plots reoeived one application of 2 percent and 3 percent dust respectively, combined with 50 percent sulfur and talc. One application of these dusts at 40 pounds per acre was not effective.— Jones (230 , 232 ). Rhagoletis pomonella (Walsh), the apple maggot, the blueberry maggot Results obtained with DDT were promising enough to warrant further tests.— Baker and Porter (81). Four applications of emulsive summer oil containing DDT, used to give about 2 ounoes of DDT per 100 gallons of spray, and timed to cover the period of first-brood attack, gave a considerable degree of oontrol and a long lasting residual effect against second-brood infestation.— Cleveland (114). In test6 made in New Hamphsire apple orchards during 1944 Gesarol AK-20 spray was superior to lead arsenate.— Conklin (116 ) • -149- In laboratory tests DDT (in acetone suspension) at 1 pound per 100 imperial gallons of -water gave poor results as a residual poison on fruit. No flies were killed within 24 hours, and some were still liv- ing after 14 days. Two sprays of calcium arsenate in bordeaux ( 10-10-100) gave better control than two applications of Gesarol A-3 dust (3 percent DDT) in a field test on blueberries in New Brunswick.— Ross (306) . A plot of 43 trees in an old apple orchard was dusted three times with Gesarol A-3 dust (3 percent DDT). At harvesttime, 97 percent of the dusted apples and 100 percent of the check apples were stung. There were 8.68 stings per dusted apple and 25»92 stings per oheok apple, a reduction of 86 .5 percent on the dusted plot*— Lathrop ( 244) ♦ Miscellaneous Diptera Examination of "the ground under hairy vetch at Oregon City, 0reg», diaeXosred that 5-percent DDT dust had killed agromyzids and scatophagids. Syrphid larvae, whioh were abundant, appeared to be unaffected •— Rookwood and Reeher (503) ♦ Solutions of 1.2 and 2.4 percent of DDT in oil seemed to have an effect in reducing populations of a predaceous fly Thamat om yia glabra (lleigen), and parasites of the genus Solenotus (parasites on larvae of the pea leaf miner), all on peas. No apparent effect was obtained on chalcid parasites of the pea leaf miner.— Lange (241). SIPH0NAPTEBA Pulioidae Ctenocephalides canis (Curt.), the dog flea Fleas on short- and long-haired dogs were controlled with Neocid A-5 and A-10.— Parker (287 ) • DDT is a contact poison.— Domenjoz (135 ) • A 10-percent DDT dust controlled fleas on dogs.— Haseman (205 ) . Ctenocephalides felis (Bouche), the oat flea Cat and dog fleas in the basements of houses have been destroyed wi"th 3 percent DDT in pyrophyllite applied at 2 ounces per 100 square feet»— N. J« Agr. Expt. Sta, (275) . Pulex irritan8 L», the human flea DDT is a contact poison.— Domenjoz (135) . -160- Xencpsylla cheopls (Rotsch.), the oriental rat flea Chicken houses which were in bad condition and contained much litter were heavily infested with rat fleas. The rami was heavily infested with rats. One- fourth pound of 3 percent DOT in pyrophyllite per 100 square feet failed to give results. Repeat tests using 5-percent DDT dust gave satisfactory results. A heavy infestation of fleas in a build- ing in good oondition was treated with 1/4 pound of 5 percent DDT in talc per 100 square feet. There were very few rats present. Control of fleas was excellent.--N. J. Agr. Expt. Sta. (275 ) . Unidentified fleas A 10-percent DDT dust rubbed into the fur of pets constitutes a satis* factory primary souroe of control* A 5-percent kerosene spray applied to floors, chicken houses and yards, dog kennels, and stable floors is ex- tremely effective. Persons have gained relief from flea bites by treat- ing the underolothes with a 10-percent TOT dust in talc— Freeborn ( 160 ) . At Clemson*, S. C, two basements heavily infested with fleas which were spreading up into the house were dusted with a 3-peroent DDT dust and complete relief was obtained by the following day.~Cartwright (108). A 1-percent DDT-kaolin powder was dusted on sheets of paper on which fleas were separately placed and covered with a beaker. Fleas were par- tially paralyzed in 11 minutes, totally paralyzed in 40 to 50 minutes, and killed in 700 to 740 minutes. —Sen (311 ). SCORPIONIDA Centruroides liropidus limpidus Karsch Young scorpions just after the first molt are easily killed in 24 hours by a 10-percent DDT powder, and also by a film of DDT on an ordinary filter paper. The adults of the same species are dead before 72 hours in technical DDT. Khea exposed to treated filter paper, most of the adults die about the tenth day.- Vargas and Colorado Iri6 (560) • ARANEIDA Latrodectus mactans (F.), the black widow spider Not affected during 6 days by a deposit of DDT on filter paper.— Vargas and Colorado Iris (360) . Unidentified spiders Examination of the ground under hairy vetch at Oregon City, Oreg., disclosed that 5-percent DDT dust had killed spiders. — Rookwood and Reeher (303). -151- ACARINA Eriophyidae The pear bud mite Six large trees in a Cornice pear orchard heavily infested with pear bud mites were sprayed with a mixture of 5 pounds of AK-20 (20 percent DDT) and 4 ounces of sodium oleyl sulfate in 100 gallons of water. A population count made a week later showed no apparent kill of the mites*— Borden and Jeppson (92). Ixodida® Derroaoentor and ersonl Stiles, spotted-fever tick In preliminary tests DDT was of little value in controlling this speoies of tiok. A yearling beef sprayed along -ttie back with Gesarol A spray 50 pounds (DDT 2.5 pounds) per 100 gallons of water did not appear to be resistant to ticks plaoed on the animal 1 week later* Similar results were obtained on rabbits infested 3 days after treatment with Gesarol A dust, or a spray of Heooid No. 15.— Ross (306 ) • Ornithodoros nicolloi Mooser Ornithodoros turlcata (Duges) A low percentage of DDT on filter paper killed adults within 2 weeks* By the eighth day they were unable to bite a guinea pig.— Vargas and Colorado Iris (560 ). Khipicephalus sanguineus (Latr.), the brown dog tick DDT is superior to anything yet found for the oontrol of the brown dog tick*— Anon. (15 ). A looal veterinarian reported that all tioks dusted with TDDT died within 48 hours, whereas ticks which dropped from tine dog when treated with a pyrethrum dip recovered and lived as long as 42 days.— Cartwright (108). This tiok proved difficult to control with Neooid A-5 and A-10. Approximately 50 peroent of these tioks on the dogs and about the premi- ses of the dog owners were destroyed.— Parker (287 ) • Sarooptidae Khefflidokopt e s gallinae (Raill.), the depluming mite Chickens badly infested wiiii this mite and the hen house were dust- ed with a 5-percent DDT dust. After 2 weeks the treated ohickens were -152- almost completely free from the mites and began to put on new feathers. The second application completely rid the birds of -the pest.—Granovsky (187). SarcopteB scablel (Deg.) Against human scabies DDT is surprisingly inefficient. A saturated solution in oil, or an emulsion in water applied to the skin, kills less than 50 percent of the Sarcoptes in 24 hours, whereas benzyl benxoate emulsion or sulfur ointment will kill well over 99 percent. DDT is cer- tainly not to be reoammended for the treatment of scabies .--Buxton ( 100) • SaroopteB suis Gerlaoh DDT in aqueous suspension did not control sarcoptio mange on pigs. —Shu 11 et al. (315 ) . Notoedres muris (Megnin), notoedric mange on rats A 1-peroent solution of DDT in liquid paraffin or olive oil had very little effeot. A 2-peroent solution led to the death of some of the experimental rats after the development of marked hyperaesthesia and frequent clonio muscular spasms.— Taylor (343, 544 ) . Tetranyohidae Paratetranyohu3 oitri (McG.), the citrus red mite DDT apparently is not toxic to this mite at the dosages required for codling moth control.— Baker and Porter (81). In all orchards in which DDT was used there was an inorease in the citrus red mite population, and in an orchard in Buena Park, Calif., the citrus aphid3, as well as the oitrus red mites, became serious pests, whereas neither were of any commercial importance in plots where oil only was used. "Where DDT was used with kerosene, or as an aqueous sus- pension of powdered solids, or in dust form there was a greater increase in the mite population than where it was used in regular spray oil.— Ebeling (142). Paratetranyohus pilosus (C. and F.), the European red mite Destructive increases in mite population at Vinoennes, Ind., did not ooour in plots in whioh low dosages of DDT (4 ounces per 100 gallons) were used, but they did oocur in most plots in whioh higher ones were used. At the dosages required for oodling moth control, DDT seems not to be toxic to this species. The use of DDT has in several cases caused an inorease in mite population, apparently by eliminating or reduoing the numbers of natural enemies of mites.— Baker and Porter (81). -153- DDT had little or no direct effeot on this mite, but by its drastic action on the mite's enemies, it encouraged outbreaks of this mite in the plots sprayed with DDT for codling moth control. --Ross (306). Dormant miscible oil containing 5.12 ounces of DDT per 100 gallons controlled the hatching and development of this mite to some degree as compared with untreated checks, but was definitely inferior to a tar-petroleum blend miscible oil. Applied as a summer spray, 2 ounces of DDT per 100 gallons when used with emulsive summer oil at 3 quarts per 100, did not appear to permit build up of initially strong mite infestation, as DDT seems to have done when used without oil. The effectiveness of summer oil did not seem to be notioeably impaired by DDT.— Cleveland ( 114 ). In the 1944 season in New Hampshire complete control of the European red mite on apples was obtained with a delayed dormant application of 1 gallon of Niagara No. 6 dormant oil plus 2 pounds of Gesarol AK-20 to each 100 gallons* of spray. This compared favorably with the recommend- ed spray of 3 gallons of oil to 100 gallons. However, sinoe none of the plots reoeived an application of 1-peroent oil alone, one cannot oonolude that the DDT was actually responsible for the degree of control obtained. — Conklin (116). Development of mites was oonspicuous on the foliage of all trees sprayed with DDT in oodling moth experiments. Bronzing of leaves was much in evidenoe.— Hough (217 , 218) . DDT was absolutely no good*— Hutson (220 ) • At certain dosages in the range required for effective codling moth oontrol DDT is very toxic to important predators of the European red mite and common red spider. Under favorable weather conditions mite populations have built up in record breaking time in DDT-sprayed plots to extremely destructive levels.— Steiner et al. (534) . Tetranychus atlanticus McG., a red spider There was no apparent control on small cotton plants lightly in- fested and dusted with a 3-peroent DDT dust (A-3) at the rate of 25 to 30 pounds per acre.— Smith (324) . Tetranychus bimaculatus Harvey, the two-spotted mite Two-spotted mites increased in numbers when treated with eight applications of 5 percent DDT in light summer spray oil— •average about l/2 gallon per acre— made by hand atomizer from June 6 to August 1.- Gray (188). -154- A heavy infestation of mites (the brown almond mite and the two- spotted mite) built up in three almond trees that were sprayed with 1 pound of DDT per 100 gallons of water, which soon evidenced severe injury. As the season progressed, the trees immediately adjacent to the DDT-treated trees showed an inorease in the mite population — un- questionably because of migration from the three sprayed trees. The sprayed trees finally suffered complete defoliation, whereas those in the main portion of the orchard retained their leaves. —Swans on and Michelbacher (340 ). Tetranychus pacificus McG., the Pacific mite At the dosages required for codling moth control, DDT apparently is not toxic— Baker and Porter (81). Tetranyohus sohoenei McG. Same as Par at et rany ohus pilosus .— Hough (217 , 218 ) • Tetranychus wi Harnett el (McGregor) , the Willamette mite At Hood River , Oreg», during September, a notioeable inorease of mites occurred on DDT-sprayed trees. The infestation caused notioeable yellowing of leaves, particularly on the lower inside areas of the trees .—Childa and Robinson (ill )* Tetranyohus spp«, common red spiders A 3-peroent DDT dust was ineffective .--Haseraan (203 ). Greenhouse tests » DDT applied at rates of 1 pound per 100 imperial gallons of water and higher, both powder suspensions and in Velsicol emulsion, has shown no apparent effect on this mite.— Ross (306). Red spider seriously damaged bean plots treated with a 3 percent DDT dust or a spray containing 1 pound of DDT in 100 gallons of water. —N. J. Agr. Bxpt. Sta. (275) . In a Bartlett pear orchard in the Sacramento River area of California red spider injury appeared earlier and was more severe in DDT-treated plots than in the remainder of the orchard receiving the regular program of lead arsenate and dinitro.— Borden and Jeppson (91). A heavy application of Gesarol A-3 dust to oantaloup in a greenhouse wa3 ineffective against red spiders and severely burned the leaves.— Ewart (145). In tests on eggplant in Nebraska red spider mites began to show up on the DDT-treated plots late in the season and they soon increased to -155- such an extent that the plants turned yellow and died prematurely. Only slight and insignificant populations developed on the cryolite-treated plants and still fewer on the untreated plots* Before the mite popula- tion "began to develop, however, DDT-treated plants appeared to have a healthier, greener color than the other plants*— Tate et al* (342) * A 3-peroent DDT dust was not effective in controlling red spiders on strawberries.— talker (366 )* Mites on guayule were readily controlled with emulsions containing 0*15 to 0*3 percent of DDT •—Craighead and Brown (125) • Bartlett pear trees developed a rather heavy infestation of spider mite with considerable foliage injury showing at -the time of the fifth oover spray* The injury appeared just as severe in the DDT plots as in the lead arsenate plots* An application of DN-111 was made the day following the fifth cover* Good oontrol of the mites resulted and no injury followed*— Childs and Robinson (111) * On apple and peach trees sprayed with DDT for control of the codling moth and the oriental fruit moth there was a tendency toward a build-up of red mites, and in some cases it was serious enough to require special sprays*— N* J* Agr* i&cpt* Sta* (275 ) > In plots at Tallulah, La*, and Brownsville, Tex*, dusted with DDT red spiders were increased somewhat by the treatment but did not become sufficiently abundant to cause damage*— Loft in (24 7) * Trombioulidae According to unpublished information from McCullooh working on DDT against trombiculid larvae in New Guinea, freshly impregnated gar- ments protect man from attack, but after these garments are washed some larval mites succeed in attaching themselves and bite after the third wash* Larvae allowed to run on oloth freshly impregnated with 1*5 per- cent of DDT were paralyzed in about 30 minutes* After the oloth had been washed twice in cold water the time was 120 minutes*— Buxton (100 )* DDT is of no use as an acarioide*— Simpson (320) « -156- INDEX OF COMMON AND SCIENTIFIC NAMES OF INSECTS Acanthoclnus spp., 79 Aoeratagallia uhlerl f 52, 67, 68 Acheta— (r Gryllus ) assimills , 37 domesticus , 37 Acrobasie caryae , 115 Acrosternuir. hilsre , 72 Adalla bipunctata , 87 Adelphocoris — llneolatus , 66 rapidus , 66 super bus , 67, 73, 74 Aedes — aegypti, 130, 133, 134 sollicitans , 130, 132, 134, 136, 137 taaniorhynchus , 134, 135 ▼e'xana , 131 Agrlotes— llneatus , 93 obscurus , 93 Alabama argillacea , 110 Alfalfa caterpillar, 117 Alsophila pometaria , 103 Ambrosia beetle, §8 Anagrapha falcif era , 111 Anarsia lineatelia , 102 Anasa tristis , 64, 60, 62, 100 Ancylis coup tana fragariae , 105 Angoumois grain moth, 103 Anguilluline dipsaci — e Dipylenchus dipseci filipius , 33 Anisota rubicunda, 101 Anopheles — albimanus, 131, 135, crucians, 132 136 funestus , 132 maculip'ennis , 132 quadrima'culatus , 132, 133, 134 triannulatus , 136 spp., 136, 139 Ants- Argentine, 126 black carpenter, 126 carpenter, 126 cornfield, 126 coushi, 125 pavement, 127 Pharaoh, 126 thief, 126 unidentified, 127 Anth onerous— eugenll , 88 grandls , 89 signatus , 89 Ant i cars ia gemnatllis , 115 Anuraphis roseus , 44, 50 AonidleJTa aurantii , 58 Aphelinus mall, 47 ijiiTls] — See under speoific kind. Aphidoletes ■«., 138 Aphis— "" gossypll , 45 pomi , 46 spl'raecola , 46 Apis cell if era , 124, 128 Aphrophora saratogensis , 61 Apple-- aphid, 46 grain aphid, 50 leafhopper, 55 maggot, 148 Archips — argyrospila , 122, 104 fumiferanaT 122 rosaceana , 123, 124 Argyrotaenie irariane , 123 Arroadill'id'ium'^vulgare , 38 Armyworm— yellow^striped, 115 beet, 113 Ash-gray blister beetle, 94 Asiatic garden beetle, 95 Asparagus beetle-- common, 80 spotted, 80 Aspldiotus perniciosus , 59 -157- Atta cephalotes , 125 Attagenus plceus, 92 Autographa — brassicae , 42 sp., 110 Autoserica castanea, Tie 95 Bagworm, Banded greenhouse thrips, 40 Bark beetles, 98 Bean— • thrips, 40 leaf beetle, 79 Mexican beetle, 87 Bedbug, 65 Beet— armyworm, 115 leafhopper, 57 Beetle. See under specific kind* Bembecia marglnata , 100 Black carpet beetle, 92 Black chrysanthemum aphid, 47 Blackfly, 146 Black scale, 61 Blapstinus auripilis , 98 Blatta or! entails , '35 Blattella germaiiica , 56 Blissus Teucopterus , 66 Blueberry maggot, 148 Boll weevil, 89 Bollworm, 111 pink, 102 Bovicola bovis , 39 Boxelder bug, 66 Boxwood- leaf miner, 138 psyllid, 62 Brevlcoryne brassicae , 46 Brown cotton bug, 73 Bruchus — brachialis , 77 pisorom ,~T8, 84 Budworui"" 1 spruce, 122 tobacco, 115 Bupalus piniarius , 103 Byturus tomentosus , 78 Cabbage- aphid, 46 imported worm, 117 looper, 113 maggot, 129 seed pod weevil, 89 webworm, 119 Cadelle, 94 Caenurgina sp., Ill Calliphora vomitoria , 129 CalocorJT~norvegicus , 67 Camnula " "p"elluoida , 34 Camponotua herculeanus — pennsylvanious , 126 spp., 126 Cankerworm, fall, 103 Carpocapsa pomonella , 105 Carrot rust fly, 145 Cat- flea, 149 Catalpa sphinx , 121 Cattle biting louse, 39 Centruroides limpidue— limpidue , 150 Ceraroica piota , 110 Ceratomia catslpae , 121 Cerotoma"tr ifur cata , 79 Ceutorhynchus assimilis , 89 Chaetocnema pulicaria , 79 Cherry fruitfly, black, 148 Chestnut weevil, 90 Chicken body louse, 38 Chinch bug, 65 Chlaroydatua associatus , 67 Chlorochroa — ligata, 72 sayl , 72, 67, 68, 74 Chromaphis juglandicola , 46 Chry s anth emun— gall midge, 138 thrips, 41 Chry somphalu a— aonidum , 59 dictyospermi , 59, 60, 61 Chrygopa— flavida, 14T -158- spp», 147 Cigarette beetle, 77 Clmex leotularius , 63 Citrus— mealybug, 61 red nite, 152 thrips, 40 Clothes moth, 122 Cnepha8ia longama , 124 Coccus— hesperidum , 60 pseudohesperidum , 60 Cockroach (es) American, 37 German, 35 oriental, 35 unidentified, sp., 37 Codling moth, 105 Coleophora roalivorella , 101 Colias eurytheroe , lli" Colorado potato beetle, 85 Common oattle grub, 145 Comstook mealybug, 61 Conchuela, 72 Confused flour beetle, 99 Conotrachelus nenuphar , 89 Com— - borer, European, 120 earworm, 111 fleabeetle, 79 rootworm, 81 Corythucha cydoniae , 74 Cotton— aphid, 45 fleahopper, 71 leafVorm, 110 Crambu8 topiarius , 101 Cranberry girdler, 101 Creontiades femoralie , 67 Cricket- field, 37 house, 37 Crioceris — • asparagi , 80 duoriecimpunctata , 80 Ctenocephalides — canis , 149~ felis, 149 Culex— pipiens , 130, 133, 137 quinquefasciatus , 134, 137 salinarius , 157 terr itan8, 137 CurcuTTJ caryae , 90 rectus , 90 Cylas forcicarius— elegantulus , 90 Cyclocephala borealis , 95 Cylindrocopturus — eatoni , 90 Darkling beetle, 98 Da tana integerriroa , 105 Deer flies, 147 Dendroctonus engelrranni , 98 Depluming mite, 15"i Derma cent or andersoni, 151 Dermestes — lardariue , 95 ■gulplnusT 93 Diabrotica— duodecimpunotata , 80, 82 longicornis , 81 11-punctata , 81 Tittata , 81 Diamdndback moth, 103, 118 Diaphanla— hyalinata , 119 nltidalis , 110, 119 Diarthronomyia hypogaea x 138 tiiaspis boisdu-yalii j 60 Diatraea saccharaTTs , 101, 118, 128 Dictyoepermum scale, 59 Dikraneura cockerellli , 52 Dlprion f'rutetorum , 127 Dog- flea, 149 Earwig, European, 38 Eastern tent caterpillar, 104 Eelworm, onion, 33 Eggplant flea beetle, 83 lleven-spotted beetle, 81 Ijtopoasca— abrupta , 52 fabae , 52, 121 maligna, 46, 55, 58 -169- Engelaaxm spruce beetle , 98 Bom ena cant hus straminens , 58 Ephestla elutella , 115, "77 Bpicauty -' ieanlscata , 94 spp», 94 Epllaohna Tarivestis , 87 Bpltrix— " cucumeris , 82, 88 fuecula , 83 hirtlpennl s, 83 parvula , 85 subcrinita , 84 tuberis, 84 spp., 84 ErlQ8oma lanlgerum , 47 Brythroneura — coroes , 66 elegantula , 56 variabilis , 52, 66 spp», 57 Etiella tinckenella , 116 European elm bark beetle, smaller, 98 Buschistus— » Impictiventrls , 75 servus, 75*"" Butettlx tenellus , 57 Bye-spotted budmoth, 11© Fannla canicularis , 128, 144 Feltla "subterraneeT , 110, 119 Ha'ia viticida , 84 Fig scale, 60 Filbert worm, 109 Fire ant, little, 127 Firebrat, 33 Flea- cat, 149 dog, 149 human, 149 oriental rat, 150 unidentified, 150 Flea beetles* See under specific kind* Fleahopper, 67 Florida red scale, 69 Flower thrips, 39 Forficula auricular la, 38 Formica sp., 127 Franklini ella— fuaca , 59, 41 helianthi , 59 ooci dental is , 40 Froghopper, 51 Fruitfly* See under specifio kind# Fruit moth, oriental, 108 Fruit tree leaf roller, 122 Fruitworm— cranberry, 116 raspberry, 78 strawberry, 124 tomato, 111 Fuller rose beetle, 91 Garden— fleahopper, 67 webworm, 119 Gladiolus thrips, 41 Gleosporium perennans , 47 Glossina spp«, 158 Glyptoscelis squamulata , 94 Gnorimos chema" * "bper cu 1 ella , 102 Grain beetle, saw-toothed, 88 Grain borer, lesser, 77 Granary weevil, 91 Granulate cutworm, 110, 119 Grape- bud beetle, 94 leafhopper, 66, 67 mealybug, 61 rootworm, 84 Grape berry moth, 109 Graph olitha molesta , 108 Grass webworm, 118 Grasshopper— olear-winged, 54 differential, 34 lesser migratory, 34 red-legged, 34 two-striped, 34 unidentified, 35 Gray-banded leaf roller, 123 Green chrysanthemum aphid, 50 Green peaoh aphid, 50 Greenbottle fly, 129 Greenhouse- leaf tier, 120 -180- whitefly, 44 Gypsy moth, 104 Haematopinus— asinl, 75 eurysternue , 75 pillferus , 76 suis , 7^ unidentified sp., 76 Halticus bracteatus , 67 Harlequin bug, 73 Heliothis-- araigera , 50, 111 virescens , 113 Hellula undalis , 119 Hemerocampa vetusta , 104 Hemispherical scale, 61 Hsrcinothrips — » femoralX? , 40 fascistus , 40 Hickory sfauckworn, 109 Hide beetle, 93 Hog louse, 76 Horoadaula albisslae , 103 Honeybee, 12*4 Hornfly, 144 Hornworn—*» tobacoo, 122 tomato, 121 Horse suoking-louse, 76 Housefly, 159 little, 128 Hyleaya— antiqua , 128 brassioae , 129 floralis , 129 Hyphantria ounea , 101 Hypo derma — bovis , 146 lineatmo , 146 Indian meal moth, 116 Iridomyrmex humilis , 126 Japanese beetle, 96 Keiferia lycopersicella , 102 ftnemidok"opTe8 gallinae7 151 Lacebug, 7*4 Lady beetle, two-spotted, 87 Laemophloeus ferruginous , 88 Laphygroa exigua , 115 Larder beetle, 93 Lasioderaa serricorae , 77 Lasius nlger allenus amerioanus , 126 Laspeyresia caryana, 109 Latrodectus mac tans , 150 Leaf -footed bug, 65 Leaf roller. See under speoific kind. Lepidosaphes — flcifollae , 60 fious , 60 tuberculatus , 60 ulmi , 60 Lepisma saccharina , 33 Leptinotarsa decemlineata , 85 Leptocori8 trivittatug , 65 Le'ptoglossus phyllopus , 65 Lima bean pod borer, 116 Limonlus— agonus , 95 eallfornicus , 95 canus , 93 spp., 94 Llstroderes obliquus , 90 Locust borer, 79 Looper, 110 oelery, 111 Louse (lioe) — body, 76 crab, 77 head, 76 unidentified sp., 75 (see also under specific kind)* Loxostege similalis, 119 Lucilia- (,« Phaenicia ) sericata , 129 caesar , 129, 144 Lyjjus-- ellsus , 67, 68, 69 hesperus , 68 ob lines tus , 66, 69, 70 spp., 70, 73 Macrobasis fabricii , 94 Macrooentrus ancylivorus , 108 Macrodactylus subspinosus , 95 Macrosteles divisus, 57 Macrosipnum solanifolii , 82, 121 >sipho niel la— >isl, 48 icroi -161- sanborni, 47 solanifolii , 49 Maggot (.See under specific kind). Malaco&oma americana , 104 MansoniaHFasciolata , 136 Mantis- praying, 38 Maple worm, green-striped, 101 Mealybug- citrus, 61 Comstoek, 61 grape, 61 Megacyllene robiniae , 79 Meianoplus — bivittatus , 34 differentialis , 34 *?emur-rubru3> , 34 mexicanus , 34 Melissop us iatiferreanus , 109 Melittiasatyr inif ormis , 100 Melon aphid, 4$ Melonworra, 119 Milkweed bug, large, 66 Mimosa webworm, 103 Mineola vaocinii, 116 Miscellaneous— doleoptera , 99 Di pt era , 149 Mite ^See under specific kind). Monartfar opa lpu s buxi , 138 Monochamus' sppT, i$ Monoroor£um pharaonls , 126 Mosquito— common malaria, 132 northern house, 137 salt-mar ah, 130 yellow-fever, 130 Murgantia histrionics , 73 Musca domestica , 129, 139, 141, 143, 144, 145, 147 Muscina stabulans , 144 Mytua persioae , 50 Kabis — alternatus , 72 ferus, 72 Neodiprion lecontei, 127 Horthern cattle grub, 145 Nojtoedres rnuris, 152 Notoedric mange on rats, 152 Oblique-banded leaf roller, 123 Olive scale, SO Onoopeltus fasciatus , 66 Onion— eelworm, 33 maggot, 128 thrips, 41 Oriental fruit moth, 108 Orius— " Tnsidiosus , 62 tristicolor , 63 Ornithodoros— " ntcollei , 151 turicata , 151 Oryzaephilus Surinam ens is , 88 Oystershell scale, §0 Pachygariola phaeopteralis , 119 Pacific Coast wireworm,"9"3 Pacific mite, 154 Pangonia inclsa— {- Esenbeokia inoisuralis ) , 147 Pantomorns— ;odmani , 91 Leucoloma , 18, 91 Parasite, internal, 47, 108 Parat etra ny chu s— ciffil , pilosus , 152, 154 Paratrloea cockerelll , 62 Paria oanella , 86 Parlatoria — ""ohinensis, 60 proteus , 61 Pea- weevil, 78 aphid, 48 Peach borer, lesser, 100 Peach twig borer, 102 Pear— psylla, 62 thrips, 40 Pear bud mite, 151 Pecan nut oasebearer, 115 Pecan weevil, 90 Pectinophora gossypiella , 102 Pedi cuius— -162- humanus corporis , 76 humanus humanus , 76 Pepper- maggot, 147 weevil, 88 Perennial canker, 47 Periplaneta americana , 37 Philaenus leucophthalrous , 51 Phlebotomus spp., 129, 136 Phlyctaenia rubigalis , 120 Phthirus pubia, 77 Phyllophaga spp., 96 Phyllotreta spp«, 87 Pickleworm, 119 Pieris ran ae, 104, 114, 115, 117 Pine sawf ly— importea, 127 red-headed, 127 Pinworm, tomato, 102 Pissodeg strobi, 91 Pistol casebearer, 101 Plant bug— onion seed, 71 rapid, 66 tarnished, 69 western, 68 Plodia inter p unctella , 116 fium curculi'o, 89 Plutella maculipennis , 103, 118 Polychrosis viteana, 109 Poplllla japonica , 57, 96, 109, 121 Porth stria diapar , 104 Potato- aphid, 49 flea beetle, 82 leafhopper, 52 psyllid, 62 tuber worm, 102 western flea beetle, 84 Prodenia praefica , 113 Protoparce — qu inqu ema cu lata , 121 "secta , 12% Psallu'e— anoorifer , 71 serlatus7 71 Pseudococous— citri, 61 com stock! , 61 maritimus , 61 Pseudoparlatoria perlatorioides , 61 P3ila rosae , 145 Psorophora — ciliata, 134 conflnnis , 134 Psylla — buxi , 62 pyricola , 62 Pulex irritans , 149 Pyrausta nubilalis , 120 Radish fly, 129 Raspberry root borer, 100 Rat, oriental- flea, 150 Red flour beetle, 99 Red mite, European, 152 Red soale, California, 58 Red spider, 153, 154 Reproduction weevil, 90 Rhagoletis — c era si ', 148 cinguJata , 148 fausta , 148 pomonella , 148 Rhipi oephalu s sanguineus , 151 Rhizopertha dominioa , 77 Rhodnlus s"p«, 7*5, 141 Rhopalosiphun— prunTfoliae , 60 pseudobrassicae , 50 rux'omacu latum , 50 Rice weevil, 92 Rootworm (See under specific kind) • Rose chafer, 95 Rose leafhopper, 58 Rosy apple aphid, 44 Rust-red grain beetle, 88 Saissetia — heroisphaerica , 61 oleae , 61 San Jose Scale, 59 Sand fly, 129 Sarcoptes — soabTei , 152 "suls , 152 Sawfly (See under specif io kind) • -163- Scirtothrip3 citri , 40 Scolytus — - gultistriatus , 98 rugulosus , 98 Short-nosed cattle louse, 75 Shot-hole borer, 98 Silverfish, 33 Simulium spp., 146 Sipha fl'ava , 50 Siphona irritans , 144 Sitophi'lus — granarius, 91 oryza , 92, 95, 103 Sitotroga cereal el la , 103 Six-spotted leafhopper, 57 Soft seale, 60 Solanopsi3 moJLesta, 126 SoJubea pugnax,, 74 Sowbugs, 38 Sphaerophoria cylindrioa , 146 Spiders-- black widow, 150 red, 153, 154 unidentified, 150 Spilographa— ele'ota" ""(s Zonosemata ) electa , 147 Spilonota ocel'lana , lfO*"" Spirea aphid, 46 Spittlebug— Saratoga, 51 unidentified, 51 Spotted cucumber beetle, 80 Squash-- borer, 100 bug, 64 Stablefly, 144, Stinkbug — green, 72 rice, 74 Say, 72 Stagmomantis sp#, 38 Stethorus punctum , 88 Stomoxys — calcitrans , 144, 145 spp., 145 Strawberry- leaf roller, 105 root worm, 86 weevil, 89 145 Striped cucumber beetle, 81 Sugar-beet vrireworm, 93 Sugarcane borer, 101, 118 Sweetpotato weevil, 90 Synanthedon pictipes, 100 Tabanus — abactor , 147 equal i s", 147 gracilis , 147 lineola , 147 Taemiothrips— in'consequens , simplex, 41~ 40 QPJ 127 146 33 Tenebroides mauritanicu s, 94 "Termites,' 3& Tetramorium caespitum, Tetranychus — atlantious , 153 bimaculatus , 153 pacificu3 ,*~154 schoeneT 7 154 wiliame£tei , 154 spp*, 154 Themira putrls , 139, Thermobia domestica , Three-lined blister beetle, 94 Thrips— nigropilosus , 41 tabaci, 41, 114 unidentified , 43 Thyanta custator , 74 Thyridopteryx ephemeraeformis , 118 Tick— spotted-fever, 151 brown dog, 151 Tobacco- flea beetle, 83 moth, 115 thrips, 39 Tomato— pinworm, 102 hornworm, 121 Trialeurodes — abutiJonea , 44 ep., 44 Tribolium— caataneuro , 99 confu8um 7 99 Trlcho gramma 3p., 128, 102 -164- Trlohodeotes — pilo8U7ij7 39 scalaris , 39 Trichoplusia nl, 46, 50, 104, 113, 117. 113 Tuber flea beetle, 84 Tuberworm, 102 Turnip aphids, 60 Tussook moth, western, 104 Two-spotted mite, 155 Typhlooyba — pcanrla , 58 ro8ae, 58 «PP«, 58 Unidentified— Coooinellidae, 88 aphid, 50 leafhoppers, 58 Lepidoptera, 124 sp., 58, 146 Vanhoutte spirea, 46 Vegetable weevil, 90 Velvetbean caterpillar, 116 Vespula arenaria , 128 Vetoh bruohid, 77 Walnut aphid, 46 Walnut caterpillar, 105 " fi Tasroannia auropunotata . 127 Wasps, unidentified, 128 Webworm, fall, 101 Western clover leafhopper, 52 Western flower thrips, 40 Western pot a to leafhopper, 52 Western tussock moth, 104 White-apple leafhopper, 58 "White -fringed beetle, 91 White grubs, 96 annual, 95 White pine weevil, 91 Willamette mite, 154 Wireworm, eastern field, 93 Wood borers, 79 Woolly apple aphid, 47 Xenopeylla cheopis , 160 Tallow sugarcane aphid, 50 Zebra caterpillar, 110