LIBRARY STATE PLANT BOARD Vr. (s \ May 1943 E-593 UNITED STATES DEPARTMENT OF AGRICULTURE AGRICULTURAL RESEARCH ADM INI STRATI 01! .BUREAU OF ENTOMOLCGY AND PLANT QUARANTINE A RE7IEYI OF THE INSECTICIDAL USES OF ROTSNONE AND ROTENOIDS FEDM DERRIS, LONCHOCAHP US (CUBE AND TIMBO), TEPHROSL-, AND RELATED PLANTS PART III. KOMOPTERA 1/ By R. C. Roark, Division of Insecticide Investigations CONTENTS Page Introduction --------------- 2 Homoptera ----------------- 2 Aleyrodi&ae" -------------- 2 Aphiidae ---------------- 4 Cercopidae --------------- 63 Chermidae --------------- 64 Cicadellidae -------------- 65 Cicadidae -..------..------ 72 Coccidae ---------------- 72 Fulgoridae ---------------- 82 Hembracidae -------------- 82 Psyllidae -- „__-_--___- 83 Insect index --------------- 85 Literature cited ------------- 93 Junior-author index ------------ 120 y The manuscript of this publication was read by the following leaders of research divisions of the Bureau, who contributed helpful suggestions: D. L. Van Dine, Fruit Insect Investigations; 7. r . H. Tflhite, Truck Crop and Garden Insect Investigations; R. W. Harmed, Cotton Insect Investigations; F. C. Bishopp, assistant chief of Bureau, formerly in charge of Insects Affecting J.ian and Animals; C. F. W. Muesebeck, Insect Identification; L. A. Hawkins, Control Investigations; and C. M. Packard, Cereal and Pbrage Insect Investigations. The assistance of specialists in the Division of Insect Identification in classifying the insects men- tioned herein as to order and family is gratefully acknowledged. IlUM 1 8 1943 - 2 - I.7TR0DUCTI01T This is the third in a series of papers designee 1 , to review all avail- able information on the insecticidal uses of rotenone and the rotenoids. Part I reviewed tests with Derris , cube, timbo, Tephrosia , Mundulea , and their constituents on members of the orders Collembola, Orthoptera, Derma'n- tera, Odona.ta, Isoptera, Corrodentia, and Mallophaga. Appa.rer.tly no tests with the rotenone plants on Thysanura, Ephemerootera, or Plecoptera have been recorded. Part II reviewed the tests made on Thysanopter? . Part III, the present paper, rpviews the tests on Homoptera. HOMOPTERA Aleyrodidae Di al euro des chittendoni Laing, a rhododendron whitefly ••'ilson (709) in 1929 reported that sprays containing nicotine and derris were found to be les^ toxic than a 2-percent oil snray to nymphs of this whitefly infesting leaves of Rhododendron jacksoni and R. -ponticum in England. Dialeurodes citri (Ashm.), the citrus i^hitefly Cnbe extract in oil, emulsified in water with oowdered milk ( CT.be extract 1:75,000, oil 0.33 percent), killed 97«^+ percent of the larvae, as compared with 79-9 percent killed by the check oil; of the eggs 23.6 percent «ere killed ~oy cube extr-ct in oil (cube extract 1:^0,000, oil 0.5 percent), r s compared with 10. 5 percent by the check oil. — Turner (271) in 1932. The Alabana Polytechnic Institute (~) in 193'S reported on the ef- fectiveness of derris Powder with' various carriers against the citrus whitefly. Ir "x~eriments with -•■owdered derris added to soaps, sulfated alcohols, sulfonated castor oil, sodium s c alts of alkylated aryl compounds, oil emulsions, and other materials, the dilute oil emulsions (0»5 and 1.0 ■oercent) formed more effective combinations with derris than the more specific wetting agents. The effectiveness of derris was depressed in both acid and alkaline wetting media, and in liouid lime sulfur. With soap, derris was more effective than nicotine sulfate and organic thio- cyanate sprays. Anderson and Walker (£)_in 1939 reported on the control of white- flies on gardenias. Immature stages of the citrus whitefly on a tropical hibisOT.s plant ir. an 8-inch flowerpot in the Virginia Truck Experiment St-Mon greenhouse were not controlled by dins of nicotine sulfate plus soap or Lct^ane UUo. When the leaves of this hibiscus plant were heavily infected "ith all stages of the vhitefly and some of the leaves were turning yellow, one-half of the plant was dipped for 30 seconds in a solution containing 1 percent of a 60 percent St-^ntex Dispersing Oil (a mineral oil containing a small percentage of oleic acid and a certain slender) and Uo percent of a derris extract in camphor-sassafra,s base oil containing 5 £?n. of rotenone in 100 cc. , 1 nercent of liquid Red "A" Soap (containing Uo percent of dry soap) and 95 percent of water. The - 3 - other half of the plant was dipped for a similar length of time in a 1- percent mixture of 30 percent of Pyrolene M. F. (a sodium salt of a syn- thetic wax prepared from a vegetable base)., and 20 percent of the derris extract described above. a few ■ol ant- few we lea* res are al and 20 5 & i . contro fcions Both treatments gave 100-percent control of all stages, except for adult vhiteflies that escaped before the plant was submerged. The suffered no apparent ill effects from the treatments and within a eks the dead bodies and cast skins of the whiteflies came off the , and the plant was restored to a normal thrifty condition. Test- so recorded with Stantex R (80 percent of Stantex Dispersing Oil percent of derris extract in camphor- sassafras base oil containing of rotenone per 100 cc). The citrus whitefly was satisfactorily lied on gardenias by thoroughly- spraying with 1- and 2-percent solu- of Stantex R .emulsified with soao. Trial euro des vaporariorum (Westw. ) f the greenhouse whitefly Davidson (6^, 6U) in 1930 ma.de careful tests in a greenhouse with pure rotenone, racem-ic deguelin, tephrosin, and toxicarol. These were suspended in water by adding an acetone solution of each to water without the addition of a wetter or spreader. Results were as follows! Insecticide Concentration (sm. cc. ) Mortality o f whitefly stages Eggs . : Larvae : Pupae Rotenone ------- 1 Do . 1 Do-" 1 Do 1 Do 1 Do 1 Racemic deguelin - - - 1 Tephrosin ------ i Toxicarol ------ l Percent Percent 2-50 — — 2,000 99-1 — 20., 000 82.0 — 30,000 — 9^.9 60,000 — 88.8 100,000 9.6 9-^.7 30,000 — 23.O 20,000 lU.o — 500 25.0 — Pe rcent Tiburec and Slattny (268) in 1939 reported that in experiments with the greenhouse whitefly all the adults were dead in 30 to 38 minutes after being dusted with a powder of derri? and pyrethrum mixed with chloro- picrinat the rate of 3 cc. r>er 1000 grams. The whiteflies became very active before they died, which indicated that chloropicrin itself does not posses'; any particular insect icidal property but, by accelerating the metabolic processes in the insects, renders them more susceptible to the toxic effects of other substances. Aleyrodidae (unidentified species) Davis (66) in l n 32 stated that with penetrating miscible oils derri*-- has proved very effective against whiteflies. _ u _ Species of Aleyrod.es are not affected "by derris. — Van der Laan (178) in 1936; also de Bussy et al. (^1 ) . Etablissements Rotenia in 1932 reported in a letter to R. C. Roark that Trial euro dog sp. on tomatoes in hothouses was killed by a proprietary dust containing 12 percent of- cube having a 6 percent rotenone content. Aphiidae Anur aphis cardui (L.), the thistle aphid 1'eoton (derris extract in fish oil) 112.5 S^- plus twice its weight of soar; killed 100 percent. — Institute of Physical and Chemical Research ( l62 ) in 1927. Anur aphis maidi-radicis (Forbes), the corn root aphid The South Carolina Agricultural Experiment Station ( 2U9 ) in its annual report for 1937 reported that cotton root aphids caused great damage in the Coastal Plains area of South Carolina. Three species of aphids are usually present. Tamed in the order of their abundance these are A. maidi-radicis , Trif idaphis phaseoli (Pass . ) , and Rhopal s i phum sp. [probably R. subterrancum Mason] . The most practical approach toward controlling these root aphids appears to be in mixing some insecticide or repellent with the fertilizer and applying the mixture directly to the soil. With this in view, 36 plots were laid out in each of h fields, and each field, or experiment, was treated with 6 different insecticides replicated 6 times. One of the insecticides was derris powder (U percent rotenone) applied at the rate of SO rounds per acre. Each insecticide was thoroughly mixed with the fertilizer and applied to the soil prior to planting. Counts were then made of the number of aphid colonies present on 100 linear feet in each plot after the cotton came up, also of the total number of plants that cane up on 100 linear feet in each plot, and. later of the number that were living just before chopping or thinning. The percentage of reduction in stand Was then computed, for each treatment. At the end of the fruiting period, when all the bolls were set, counts were made of all the bolls present on. the two center rows in each plot. ITo significant differences between any 01 the treatments appeared in the number of aphid colonies, in the percentage reduction in stand., or in the boll counts. So harmful or undesirable effects were noted in the growth of the plants -from the use of any of the^e insecticides when applied to the soil in the amounts stated. Tests conducted against the root aphids T. phaseoli , R. subterra - neum',.. and. A. naid.i-rad,icis on cotton were reported, in June 193^ "oy Rain- water ( 22S ) . In the first series of experiments derris was mixed in the soil of the seedbed from 2 to 3 weeks before planting, at the rate of 100 pounds per acre. Ilhe seed came up to a good stand,. On the derris-treated -'-•lot'- 2.5 colonies per 100 row feet were present, in comparison with 7«5 and. 10.5 is the checks. In another series of tests, conducted in a field. where the cotton had been killed. b; r the aphids and it was necessary to replant the materials were lightly mixed, with the soil and the seed, was - 5 - immediately planted. Two hundred pounds of tobacco dust, to which 0.25 percent of rotenone from derris powder had "been added, was used per acre. The tobacco-derris plot came up to a good stand. In the third series of tests 1.6 -oounds of derris was mixed with 100 pounds of cotton seed just "before planting. The seed treated with derris germinated more ouickly and was up 2^ hours earlier than the checks. There was very little re- duction in the number of aphid colonies. Anuraphir. oersica.e-niger (Smith), the black peach aphid In the field the mortality of this species when sprayed with a suspension of pure rotenone in water, 1:1+0,000, was So.J> percent. Davidson (6j0 in 1930. Anura.vhi^ roseus Baker, the rosy apple aphid The ITew York Agricultural Experiment Station ( 211 ) in 1928 reported that rosy aphid infestation of a'ople trees was noticeably reduced by Der- risol. Van Surer. ( 307 ) in 1323 reported Derrisol to be effective. Farrott got about 8 percent of the rosy aphids on Rome tree<= when Derrisol a.t 1:200 was used, as compared with a little less than 1 percent on plats sprayed with lime-sulfur and nicotine sulfate. In thr field the mortality of this insect ^hen sprayed with a suspension of pure rotenone in '-'ater was 96.3 percent at a concentration of l:Uo,000 and 90.2 percent at a concentration of 1:60,000. —Davidson (63) in 1930. Parrott and Glasgow ( 220 ) in 1930 reported trials of different in- secticides against the rosy aphid in ?.7ew York. The results with the derris preparation, Derrisol, were as follows: Insecticide Aphid-attacked apples per tree Percent Lime- sulphur 1:^0 + Derrisol 1:300 22.17 Lime- sulphur l:Uo + Derrisol l:l600 + nicotine sulphate l:l600 7-39 Bordeaux U-U-50 + Derrisol 1:800 U3.90 Check plot • 51.65 In ~>ast seasons sampled of Derrisol, although consistently inferior to nicotine sprays, greatly reduced the aphid population. Both rotenone and derris extract proved much more toxic than pyre- thrum extract to this species (cf. Aphi s ^cmi Deg.). The tests were ma.de dipping apple twigs infested with these aphids in solutions of various concentrations. — Oinsburg and Schmitt ( 125 ) in 1932. Anuraphis tulipae (Fonsc), the tulip bulb aphid Dusting the bulbs with derris is effective in controlling infesta- tions of the tulip aphid. --Wilson ( 309 ) in 1938. Aphis gcssypii C-lov. , the cotton aphid, or melon aphid Mclndoo et al. (139) in 1?19 reported that the alcoholic extract - 6 - fro.! De^is elliptica roots in the ratio of 1 pound of roots to 200 gallons of water plus 4 pounds of fish-oil soap killed 100 percent of this aphid in laboratory tests. Extracts of several species of Derris were tested, as well as a derris dust which killed 99 percent. Dennis (JJ, jffi;) ^ United States Patent 1,621,240, issued March 15, 1927, and in Reissue IS, 667, issued Fove.mber 22, 193^, stated that an alcoholic extr?ct of cube is eight times as effective as' similar derris extract and is also slightly more effective than nicotine sulfate when sprayed on the cotton aphid. _ ■ When A. gossypii on celery in a greenhouse was dusted with a mix- ture of 2 r>arts of rotenone and 92 parts of diatomaceous earth, 68.9 per- cent '-'ere killed. — Davidson ( 63 ) in 193^- Little ( 183 ) in 1931 gave a detailed account of the insect'icidal properties of devil 1 s- shoestring ( Tenhrosia virginiana ) . Dried and powdered (100-mesh) roots were suspended in water and tested against many kinds of insects. When sprayed on A. gossypii at a. dilution of 1:3,200 without spreader, devil' s- shoestring gave a kill of 6U.3 percent, as compared with 82.2 percent for nicotine sulfate and 73*1 percent for 1 derris. Field tests by Little ( 182 ) with A. gossypii showed that devil' s- shoestring has considerable promise as a contact spray. This insect is easily controlled by spraying with Derrisol at 1:800 or Katakilla at 5 pounds per 100 imperial gallons. — Andrics (10) in 1932. G-off and Tiseot ( 129 ) i n 1932 reported that the melon aphid may be controlled by treating the infested plants with one of the liouid aphi- cides containing extracts of nicotine, pyrethrum, or derris. Merino and Dtanes ( 197 ) in 1937 recommended a derris- soap spray for the control of this species on cotton in the Philippine Islands. "..'ille, Ocampo, Weberbauer, and Schofield ( ^07 ) of the Agricultural Experiment Station at Molina, Peru, in 1937 reported that sprays of c'dbe extract containing 0.05 or 0.01 "oercent of rotenone proved as effective against this species as a 0. 5-percent solution of nicotine sulfate. Gunderson ( 13^ ) in 193& recommended the u<-e of derris against melon aphids. Gaines ( 11^0 in 1939 reported the tests of derris or cube added to fluorine compounds and applied as dust^. Relative Treatment a-chid -oo^ulation Calcium arsenate 100 Synthetic cryolite alone 100 Synthetic cryolite + derris (0.5 percent rotenone) 14 Barium fluosilic-te alone 103 Barium fluosilicate + derris (0.5 percent rotenone) 23 - 7 - When derris or cube was added to calcium arsenate, in no case did a damaging aphid population develop; however, at Tallulah a dust contain- ing rotenone 0.6 percent, Avirol 1 percent, water 1 percent, and peanut oil 0.5-percent, '-dth talc as a carrier, applied- after the infestations became heavy, failed to give satisfactory control. The heavy infesta- tions were satisfactorily controlled with one application of lime and nicotine sulfate containing 3 percent of nicotine. Haude ( lUU ) in 1939 wrote that there is considerable unpublished evidence indicating that the cotton aphid nay be effectively held in check with rotenone-bearing dusts. Tiburec and Blattny ( 268 ) in 1939 reported that in tests with A. gossypii a dust of derris and chloropicrin (3 cc. chloropicrin per 1,000 ga. of derris powder) proved as ineffective as a dust of derris alone. The United States Department of Agriculture, Bureau of Entomology and Plant Quarantine (28U) in 193^ reported good control of cotton aphids at Florence, S. C. , with the following rotenone dusts: 11.2 pounds of derris-tobacco-sulfur dust (1 percent rotenone) per acre; and 18. H pounds of cube- sulfur dust (1 percent rotenone) -oer acre. From these and other observations it appears that rotenone may be more effective in the pres- ence of moisture. At Tallulah, La., three plots with a medium aphid in- festation were dusted by M. T. Young with a derris-clay mixture containing 1 percent of rotenone at a rate of 10 to 13 pounds per acre. To one of the mixtures was added 1 percent of Aresket, to another 1 percent of Vatsol, while the third contained no wetting agent. Very little, if any, control was obtained from any of these applications. Another series of heavily infested plats at Tallulah was dusted by G-. L. Smith with these mixtures about the same time, also with negative results. Similar lack of control of cotton aphids with dusts containing rotenone resulted on plots dusted 'oy K. P. Swing at Port Lavaca, Tex. , in July. Aphis helianthi Mon. Mclndoo, Sievers, and Abbott ( 189 ) in 1 9 1 9 reported that 96.6 per- cent of these aphids were killed when sprayed with derris powder soaked for half an hour in soap solution consisting of 1 pound of povrder to 100 gallons of water plus 2 pounds of fish-oil soap. Aphi ^ illinoiser.sis Shim. , the grapevine aphid Dickey and Loucks (80) in 193^ recommended derris spray for the control of ( llacrosiphum ) Aphi s illinoisensis Shim, attacking grapes in Florid?.. « Aphis medicaginis Koch, the covpea aphid Castillo (U8) in 1926 reported the results of studies on the In- secticidal ^ro~erties of three- species of Derris growing in the Philip- pines, namely, D. ri ply ant ha Perk., D. philippinensis !'err., and D. elli">tica (Roxb.) Benth. The roots were cut into thin, transverse slic=^ and dried in an oven at U-0° C. until the t remained fairly constant. The dried material v, r S then comminuted in a mortar a.nd the - g - , powdering; finally com/ple.ted, in a. neat grinder. The fine -oovrder was separated .fro. m the fibers, by lifting through -fine-meshed cloth. In the comparative studies of the' effect of various-concentrations, D. philip - p inensis was used because' it was relatively- 'mcrre abundant ,• hence more easily p ; ro curable t than the other?.' 'Te-stte vere made. on mqsouito larvae and on A. medicaginis . The concentratioTi 'o"f D. ynhilipninensis which "brought about the largest number of 'death's -of aphids was much higher than that reouired for mosouito larvae, •■namely, U:1,000. The lowest concentration of 33. philippinensis used, 0. 5*1,000, caused a notice- able percentage of mortality among aphids, as compared with the control. Gaines ( llU ) in 1939 reported tests against A. nedicagin is of derris or cube a.dded to fluorine compounds and applied a? dusts (see discussion under A. £ossyp_i_i, p. 6). Aphis nerii Jonsc. • ' A commercial derris extract at 11^00 gave 13 percent control. — DeOng and White (76) in 1924. - ■ Aphis odinae (van der Goot) The Mysore, India, Department of Agriculture (203) in 193^ report- ed suspensions and alcoholic extract? of derris to "be effective against this species. Aphis papa^eris 1 , Estahlissements Hotenia in 193^, in a letter to R. C. Roark, stated that this species on cherry trees is killed by a proprietary dust contain- ing 12 percent of cube of 6 percent rotenone. content . Aphis pomi De-^;. , the apple aphid, or green a^ple aphid Mclndoo, Sievers, and Abbott (189.) in 1919 reported that derris' powder used as a dust under practical conditions was effective against green apple aphids. Kelsall et al . ( 169 ) in 1926 reported that against the green apple aphid derris, 5 pounds in 100 imperial gallons of water, without soap, gave practically complete control, "being a little superior to 1 pound of nicotine sulfate (ho percent). With the addition of a little soap to the solution, derric-- as low as 2-1/2 pounds to 100 imperial gallons 'of "water ga Tr e 100-percent mortality, ^nd is superior to 1 pound of nicotine sul- fate (40 percent). A dust containing as high as 20 percent of derris plus SO percent of hydrated lime proved ineffective against the green apple aphid when applied to dry foliage. Derris dust requires moisture to make its toxic properties effective against this aphid. Outright (60) in 193Q reported that Derrisol was -the "best of the derris products tried against a"^ple aphids. The efficacy of lime-sulfur or oil sprays against aphid_ eggs was "but little improved by the addition of Derrisol, At l:g'po Derrisol satisfactorily killed aphids if they were thoroughly wetted. '. - 9 - In the field 99 percent of the apple aphids were killed when sprayed with a suspension of rotenone 1:60,000; and 77-2 percent were killed "by a dust containing 1 part of rotenone and 99 parts of diatoma- ceous earth. — Davidson (6^) in 1930. Fulmer ( 113 ) in 1930 wrote that the green apple aphid can "be effectively controlled "by spraying with derris powder, 5 pounds per 100 imperial gallons. Ginsburg and Schmitt (12_5) in 193 2 compared the contact insecti- cidal action of rotenone and the pyrethrins on apple aphids. Apple twigs infested with these aphids were dipped in solutions of various concentra- tions of rotenone, derris, and pyrethrum extracts. Both rotenone and derris extract proved much more toxic to aphids than did pyrethrum ex- tract. Rotenone at 1:10,000 killed 93 «^ percent of the apple aphids in 2h hours; derris extract (rotenone equivalent to 1:13,200) killed 93 per- cent. Ginsburg and Granett ( 122 , 123 ) in I93U tested on the green apple aphid untreated derris powder and also the marc after extraction with acetone or with acetone followed "by water. The materials were applied in the form of coarsely and finely ground dusts. Derris-root dust (rotenone U.l percent) was more toxic against aphids when applied on wet than on dry foliage. Residues from derris root extracted with acetone possess practically no toxicity to aphids. In 193? *he same workers ( I2U ) studied the compatibility of derris in combination with other materials in tests on A. pomi . The addition of lime, lead arsenate, or sulfur, singly or combined, tended to reduce the aphicidal properties. It also appeared that with a good wetting agent a suspension of fine derris root was as efficient as a dispersion of a commercial acetone extract. Liauid lime- sulfur appeared to exert a deleterious effect on the aphicidal properties of derris. nevertheless the combination of derris root and lime-sulfur with a spreader gave sufficiently good results against the green apple aphid to warrant tests as a substitute for nicotine-lime-sulfur in the field. Ginsburg, Schmitt, and Granett (126, 127 ) in 193^ reported on the toxicity of various extracts of derris root to sucking and chewing in- sects. Tv.'o extracts of derris root, one containing a high percentage of rotenone, the other no rotenone, were equally toxic to aphids in dilu- tions of 1:20,000 or lower. 3ased on tests of extracts with different species of insects, including the green apple aphid, the following con- clusions were drawn: Water-soluble organic solvents such as acetone and alcohol are able to extract practically all of the water-soluble and "atcr-insoluble ingredients of derris root that arc toxic to sucking insects. Either continuous distillation, or soaking with subsepuent filtration and washing, extracts all the active < principles that act as contact poison when acetone or alcohol is used. Water does not extract all the toxic principles of derris root. At low dilutions the water extracts compared well in toxicity with acetone and alcohol extracts, but pro'*ed inferior to them in high dilutions. Water extracts rapidly deteriorate on standing, with resultant loss of toxicity. Alcohol extracts slowly lose toxicity upon standing. Acetone extracts do not show any appreciable changes in toxicity upon *TSTZ PLANT BOARP - 10 - * standing. . The toxicity of derris extract varies with different specie? of insects. Derris extracts were more toxic to insects than were solutions of pure rotenone, although the concentra- tion of rotenone was practically the same in each case. Rote- , none alone is not an adeauate criterion to- evaluate the toxic- ity of derris root to insects. Farrar (93) in 193^ reported that tests made in Illinois showed that extracts of pyrethrum, derris, or cube were not so efficient against A. -oomi as was nicotine mixed with oil emulsion. The addition of soap increased the killing power of an oil containing such extracts, hut not enough to warrant the added cost of the extracts. Etablissements Rotenia in 193& reported insecticide tests against A. rjomi on apple and near trees (see discussion under A. papaveris , on p. S). The Wisconsin Agricultural Experiment Station ( 321 ) in 1939 re- ported very good results with an experimental derris dust applied at the rate of about 1 pound per. tree. The mixture was made up of 12 pounds of ground derris root (5 percent rotenone), 2U pounds of talc, 12 pounds of dusting sulfur, and 12 pounds of Goulac. Within a week after this • mixture was used practically all the aphids had been destroyed. The only.aphiis found were a few winged adults that a'O'oarently. had flown in from other trees, and some offspring of such insects. A dust made up of 10 rounds of Uo percent nicotine sulfate to 125 pounds of lime, so as to give about a 3 percent nicotine content, was also tested. When used at the rate of approximately 1/2 pound per tree, this material gave only fair control. Two days after treatment the nicotine-lime mixture seemed to be giving about as good control as derris, but a week after dusting the comparison was very much in favor of derris. Aphi s ruraicis L. , the bean aphid 'Tclndoo, Sievers, and Abbott ( 189 ) i n 1919 reported that derris ponder, used as a dust under practical conditions, was effective against bean aphids. Mclndoo p.nd Sievers (128) in I92U reported cube powder to be effective against bean aphids, both as a dust and as an infusion. Fryer et al. ( 107 ) in 1923 used A. rumicis as one of the test insects to determine the insecticidal value of different samples of Derris elliotica roots. Aphids were less susceptible than were certain Gimlet te (120) in I923 reported work that H. E. Durham did with derris in 1903. Derris had no effect as a contact poison on A. rumicis . Tattersf ield and Roach ( 26k ) in 1923 referred to Durham' s work on derri= in which he found the bean aphid resistant to wet application. The Rothamsted Experimental Station ( 237 ) in I92U reported that -li- the seeds and leaves of Tephrosia vogelii were a"bout as toxic as nicotine, the test insect presumably being the "bean aphid. Tattersfield (256, 257 ) in 1925 reported that extracts prepared from "black and vrhite haiari ( Loncho carpus spp.) with water and organic solvents (particularly the latter) had "been found highly poisonous to aphids [-presumably A. rumicis ] as contact insecticides. In 1927 he re- ported that the roots and stems of "both black and white haiari were toxic to A. rumicis but that the leaves were not. Tubatoxin (rotenone) from Derris elliptic? , at a concentration of 0.25 percent, was almost com- pletely toxic to bean aphids. Six species of Tephrosia vrere also tested against bean aphids, with the following results: Snecies Parts tested Result T. vogelii ------ Leaves Do. -------- Seeds Do. -------- Stems Do. -------- Roots T. toxicaria ----- Do Do. -------- Stems Do. -------- Leaves T. macropoda ----- Roots Do. -------- Stems T. Candida ------ T. hookeriana - - - - T. purpurea ----- Toxic Do. Less toxic than leaves and seeds Do. Toxic • Do. Not toxic Toxic N Do. Low toxicity Do. Do. Tattersfield, Gimingham, and Morris (2_6l, 262 ) in 1925 reported that both alcoholic and aqueous extracts of Tephrosia vogelii Hook, were found to have high toxicity to A. rumicis as contact poisons. The toxic effect of the concentrated extracts on this insect was about the same as that of nicotine. Aqueous extracts of the leaves and seed proved very toxic when a suitable wetting reagent was used with them and were prefer- able to those made with organic solvents; the latter on drying tended to become somewhat insoluble, and the aqueous extracts had about the same toxicity. The aoueous and alcoholic extracts of a given weight of seed also had an eoual toxicity, but the dried extracts prepared by means of organic solvents were more readily worked up into an emulsion. The stems were less poisonous than either leaves or seeds. The same authors in 1926 reported that alcoholic extracts of the roots and stems of white haiari and the stem? of black haiari (both species of Loncho carpus from British Guiana) possess notable insecticidal properties ^ r hen tested on the bean aphid. Crystals isolated from these plants were identical with tubatoxin (= rotenone) from Derris elliptica . Rotenone at a concentra- tion of 2.5 to 0.075 gm. per liter killed all aphids; 0.01 gm. per liter caused 20 percent to be moribund. Rotenone proved to be several times more toxic than nicotine. The alcoholic extracts of the roots of Tephro - sia toxicaria and the leaves of T. vogelii also possess notablr insecti- cidal properties when tested on A. rumicis . The roots and stems of T. Candida are less toxic. The most toxic substances isolated from T. - 12 - toxicaria. and T. vcgelii were resinous. Crystals closely corresponding to tephrosin, as isolated by Hanriot, were less toxic. Tattersfield and Giningham ( 239 , 26o ) in 1927 referred to their previous work with white and "black haiari and stated that the tuba.toxin (rotenone) these plants contain is unauestionably one of the most potent insecticides. The toxicity to the "black "bean aphid of products isolated from haiari, compared with nicotine, is shown in graphs. In 193 2 they reported that samples of roots, stems, and leaves of Derris scandens from British G-uiana and "branches, roots, and leaves of D. trifoliata ( uliginosa ) from India and Siara showed little or no toxicity to "bean aphids. In preliminary trials the plant material was ground fine, extracted with alcohol or water, and the extracts diluted with a 0.5 percent solution of nontoxic saponin. A high concentration (equivalent to 1 to 5 percent of the "olant material) was tried first. The insect used in most of the experiments was A. rumicis , feeding on broadbean plants, and bred, so far as possible, under standardized condition?. The alcohol or aqueous extracts of Tephrosia Candida , T. purpurea , T. heckmanniana , and T. hook - eriana showed little or no toxicity. The seeds of T_. hookeriana showed some toxicity. The alcoholic extracts of the roots, and to a less extent of the stems, of T. macropoda from ITatal possess considerable contact- insecticidal value. The leaves are of little value. The bark of Millet - tia pachycarpa Benth. was not toxic, but the alcoholic extracts of stems, seeds, and peds of Mundulea suberosa Benth. from India showed definite activity as contact insecticides. One specimen of the seeds and pods of Loncho carpus latifolius from Trinidad showed slight toxicity. A. rumicis is not appreciably controlled by sprays of derris which, according to Durham (91_) in 1926, is essentially a stomach poison. In an insectary experiment it was killed completely but slowly by derris, 5 pounds to 100 imperial gallons of water, according to Kelsall et al. ( 169 ) in 1926. Neoton (derris extract in fish oil), 197.5 g™* plus an equal weight of soap in Uo imperial gallons of water, killed from 50 to 100 nercent of bean ar>hids. — Institute of Physical and Chemical Research (I62) in 1927. Turner ( 271 ) in 1932 reported the results of work carried on dur- ing 192g to 1931, inclusive, with cube extract and with rotenone obtained from cube. Davidson (6^, 6U-) in 1930 reported the following results of tests of aoueous suspensions of t>ure rotenone upon the bean aphid: Concentration Mortality (gm. :cc.) (percent) 1:100,000 99-5 1:200,000 100.0 1:300,000 97.0 A dust composed of 2 t>arts of rotenone and 98 parts of diatomaceous ■ - 13 - earth killed 100 percent of these aphids on nasturtium in a greenhouse. Racemic deguelin killed 100 percent at 1:10,000; tephrosin 100 percent at 1:5,000; and toxicarol 9^»5 percent at 1:500. Shepard, using the bean aphid as the test insect, noted that in acetone or in alcohol rotenone decomposes only very slowly, hut in aqueous suspensions made from these solutions it suffers a loss in toxi- city on standing. — Davidson and Jones (65) in 193 1 * Shepard ( 2Ul ) in 1931 tested the relative toxicity of rotenone and nicotine to the "bean aphid. The rotenone was first dissolved in 95 percent alcohol (0.25 gm. in 100 cc). It was found necessary to warm the mixture somewhat in a water bath to dissolve the rotenone entirely. On dilution with distilled water a stable millcy suspension resulted. Colonies of A. rumicis on nasturtium plants were sprayed with the various dilutions. Both rotenone and nicotine were tested in duplicate at the same concentration on the same day, all the tests being made within as few days as possible. The spray mixtures were made fresh each day. Saponin at 1-percent concentration was used as spreader, the reouired amount of stock solution of 5- to 10-percent saponin being added after the rotenone suspension was diluted somewhat with water. At concentra- tions of 0.001, 0.01, and 0.02 gm. per 100 cc. rotenone was more toxic than nicotine. Rotenone sprays prepared from acetone and alcohol stock solutions were equally toxic against A. rumicis . A suspension of rote- none (0.01 percent) in 0.01 normal sodium hydroxide when fresh killed 71.2 percent of bean aphids, as compared with 3^.7 percent at the end of 8 days. In distilled water the drop in mortality was from 93*^ to 79«9 and in 0.01 normal sulfuric acid from 93*9 to 67. percent in the same time. Acid caused a clotting of the rotenone particles. Cube extract in potassium oleate at 1:50,000 killed 9^*5 percent of A. rumicis , but after standing 18 days the kill at 1:60,000 dropped from 76. 1 to U6.7 percent, indicating deterioration of the cube extract within this time. Cube extract in oil emulsified in water with a sulfonate emulsifier (cube 1:200,000 and oil 0.5 percent) killed. 80. 3 percent of bean aphids, whereas the oil alone killed 18.5 percent. G-arman ( 117 ) in 193^ reported laboratory and greenhouse tests of commercial extracts of derris and of cube against the bean aphid on nas- turtiums. Five commercial rotenone preparations and two commercial pyrethrum-rotenone combinations were tested. It was found that the rote- none or pyrethrin content of these preparations must be increased if they are to compare favorably as aphicides with nicotine and anabasine products, Gimingham ( 119 ) in 193^ described recent work on insecticides in Great Britain. Several species of the genus Tephrosia showed marked- in- secticidal properties against aphids [probably A. rumicis ] , the leaves and seeds of T. ■"•ogelii , the roots of T. toxicaria , and the roots and stems of T. mac r op da. all yielding highly toxic extracts. Extracts of white and black haiari ( Loncho carpus spp.) from British Guiana proved highly toxic to aphids. The bean aphid' was used as a test insect by Badertscher and Wother- spoon (11_) in 1935 in testing the decomposition of derris and pyre thrum powders when exposed to the light from a Uviarc mercury-vapor lamp. An - Ik - aa.ueous suspension (rotenone l:Uo,000) made by adding an acetone extract of derris to water killed 6j.l percent of these aphids in 2h hours. Granett ( 133 ) in 1335 used Dean aphids in testing the insec'ticidal values of derris marcs extracted with certain water-soluble and water- insoluble solvents. Ethyl alcohol was the only solvent which removed practically all the insecticidal substances from derris. C-insburg and Granett (12U) in 1935 reported on the aphicidal ^ror>erties of derris and cube roof. Derris and cube, as finely ground dusts, water suspensions, and extracts, were tested against various species of aphids. Tests against A. rumicis with derris samples ranging from to 9 percent rotenone showed that the toxicity was in the order of the rotenone content, but did not bear a direct relationship to it. It was stated that a derris sample containing 5-P GI "cent of rotenone and high total acetone extractives should prove as efficient for practical purposes as root^ of higher rotenone content. The rate of kill was slower when derris was applied as a dust than when used as either water suspension or extract. Tests were made against A. rumicis of a sample of derris root and a sample of cube root to compare the aphicidal proper- ties of these materials. The derris root selected contained 5 percent of rotenone and 17-9 percent of acetone extractives while the cube root contained 5 percent of rotenone and l6.7 percent of acetone extractives. The samples were compared as dusts, water suspensions, and acetone ex- tracts. On the whole the differences in toxicity to a-phids observed were too small to warrant a definite distinction between the two samples. Apparently derris and cube, provided they have the same rotenone and total-extractive content, are equally toxic to aphids. Roark (2J$U) in 193S, in a review of the comparative value of derris and cube, referred to the work of these investigators. Lever ( 1S1 ) in 1935 published the results of tests of Derris tri - foliata from the British Solomon Islands. Specimens of roots, stems, and leaves were examined by the Rothamsted Experimental Station by spray- ing alcoholic extracts on A. rumicis. Results were as follows: Concentration of Derris species Sample alcoholic extractives Mortality Percent Percent 0.U6 Uo 1.17 60 0.U6 U 5 1.5s 71 1.37 S5 0.07 62 D. trifoliata Roots from Savo: U Do. - - - - Stems from Savo: 3 Do. - - ,- - Roots from G-izo: U Do. - - - - Stems from Savo: 6 Do. - - - - Leaves from Savo : 7 D. elli^-tica ' Roots from Malaya: 7 Martin (192) in 193& reported finding about O.U percent of rotenone in a specimen of Tephrosia macropoda Harv. from the Hiatal Herbarium, De- partment of Agriculture, Durban. Qualitative insecticide tests using a cold alcoholic extract of the finely ground root diluted with saponin solution were made on A. rumicis. At concentrations e equivalent to 0.25 ■ - 15 - and 0.1 percent of the root, the percentages of moribund and dead insects recorded on the third day after spraying were 95 and 50 percent, respec- tively. The root thus shov/s a decided toxic action to this insect. Foliafume (a pyrethrum-derris spray with spreader) at 1:^00 killed 88 -nercent in U8 hours. — Peni.ck and Company ( 225 ) in 193&- Van der Vecht ( 288 ) in 1937 tested the method of Jones and Smith (165), usi^e the results obtained by Tat ters.fi eld and Martin with differ- ent specie's of derris against A. rumicis* . This method gives good result? in evaluating derris containing more than k percent of rotenone; the toxic valve of Derris rial ace en? is (containing from to 2.7 percent rotenone) is best expressed by the formula: Value = rotenone content + 1/3 remainder of extract. Craufar&rBenson (52) in 1938 experimented with field-collected A. rumicis , but results were completely unreliable. These aphids were also reared in a greenhouse under standard conditions and used for lab- oratory testing of liquid contact insecticides, especially derris prepa- rations. The results of trials on any one day were comparable and indi- cated the comparative toxicities of the insecticides tested, but when the same insecticide was tested on different days the results were in- coordinate. ©under son ( 13^ ) in 193^ recommended derris against bean aphids. Howes ( 156 ) in 193- reported tests made at the Rothamsted Experimental Station on insects [presumably the bean aphid] with alcoholic extracts of the roots of Tephrosia macropoda cultivated in ITatal. A concentration of 0.25 percent of a 2-year-old root killed 100 percent of the insects. Tattersfield and Martin ( 263 ) in 1938 reported on the toxicity to the bean aphid of certain products isolated from derris root. The tox- icities to A. rumicis of rotenone, toxicarol precursor, sumatrol, toxi- carol, and the residual resins from the Sumatra- type and Derris elliptica roots were determined. The toxicity in descending order was rotenone > ■&• elliptica resin > Sumatra-type resin > sumatrol = toxicarol precursor > inactive toxicarol. Rotenone was 6 times as toxic as the Sumatra-type resin, h times as toxic as that derived from D. elliptica , and from 13 to 15 times as toxic as the toxicarol precursor. Aphi s sambuci L. , a black aphid Derris or rotenone suspensions at a concentration of 1:5000 or 1:6250 were effective. — DeSussy et al. (32), in 1935 . Aphis spiraecola Patch, the spirea aphid, or. green citrus aphid Mclndoo, Sievers, and Abbott ( 189 ) in 1919 reported that an alcohol- ic extract of derris added to ^ater at the rate of extract fron 1 pound of powder to 100 gallons of water, plus 2 pounds of fish-oil soap, killed only 30 percent of this aphid. When derris powder was soaked in soap solution 2 days and the mixture sprayed, 50 percent of the anhids were killed. - 16 - ' Mclr.&oo and Siegers ( 188 ) in I92U reported that a cold alcoholic 'extract -of cube plus soap in water (1 + 2 + 100) killed 95 percent of this -species" "within 2k hours. The dry cute resin dissolved in alcohol and sprayed with 'soap in water (1 + 2 + 100) killed only 60 percent with- in 2 days. Watson ( 302 ) in 1925 wrote that "Derris oil" [Derrisol?] 1 table- spoon to a gallon of water was an effective dip for the control of the citrus aphid in Florida. The infested terminal growth was bent over into a bucket containing the solution. The Florida Agricultural Experiment Station ( 102 , 105 , IOU) re- ported in 1926 .that Derrisol was tried against the citrus aphid, in com- parison with nicotine sulfate. Its action was much slower but it seemed to have a repellent effect for a day or two. It did not penetrate the curled leaves so well as did nicotine sulfate. This station in 1931 re ~ ported that an extract of Tcphrosia virginiana - was ineffective against this species; and in its annual report for 193^ stated that good control of the green citrus aphid was obtained with a product containing 50 per- cent of white oil and 0.33 percent of rotenone. Fryer ( 108 ) in 1Q26 gave the following directions for the use of Derrisol: Derrisol should be diluted with water 1:10 and this solution then added to water to make a final dilution of 1 pint of Derrisol per 100 gallons. The Derrisol should never be added directly to the water in the spray tank, 'as a dilution of uniform strength is difficult to obtain in this manner. Soap may be used with Derrisol, but its use is unnecessary. Derrisol can be used as a mixed spray with oil emulsion, lime-sulfur, bordeaux, and arsenates, care being taken that the Derrisol is added only to the diluted insecticides. It is most important not to add the Derrisol to the concentrated spray material when mixed spraying is desired, because some of the active ingredient may be thrown out of solution and the final efficiency of the spray mixture be thereby impaired. Derrisol was effective against the citrus aphid, andalso against aphids and other insect pests on hops and fruits in England. Lenfest (ISO) in 1926 mentioned Derrisol and Black Leaf Uo as about the two best contact insecticides for. use against citrus aphids in Florida. Derrisol spreads well without soap. Lime-sulfur mixed with Derrisol will kill rust mites and red spiders, as well as aphids. Miller ( 202 ) in 1929 reported tests to control the green citrus aphid in Florida. Derris extract at any of the ordinary spraying strengths was not toxic to plants. When used against aphids at 1 part .to 800 it gave a 99-P cr ccnt kill and at Ipart to 1,000 a 95-? Gr eent- kill.. This- insecticide, however, is a slow-acting material and will not kill all the aphids in 2U hours, but shows its real effectiveness in 36 to U8 hours. Miller was not able to find that derris extracts had any more lasting effect or repellent action than' nicotine sulfate. Tic-^ot and Thompson ( 269 ) in 1930 recorded the results of laboratory tests with nicotine, pyrethrum, and derris ^reparations made at Gaines- * r ille, Fla. Against the green citrus aphid, Feoton, 1-1/M- pounds- to 100 gallons of water, plus Grandpa' s Wonder Spray, 5 pounds to 100 gallons, - 17 - gave a mortality of 92. k percent. Most a'phids that, survived vrere inside curled leaven. ITeoton at the same concentration, plus Octagon laundry soap, 2-l/2 rounds to 100 gallons, gave a mortality of 81.9 percent, and plus 5 pounds Octagon laundry soap, a mortality of yk.k percent. Feoton at 2-1/2 pounds per 100 gallons, plus Octagon laundry soap, 5 pounds per 100 gallons, gave a mortality of 96.2 percent. The highest kill (92. 8 percent) in this series of tests was obtained with 50 percent of free nicotine at 1:1,000 plus 0.5-percent Penetrol. Reference to these results was made "by Thompson ( 267 ) "before the Florida State Horticultural Society at its 1930 meeting. Derrisol also was stated to give good control. Barley (S2) in 1931 reported laboratory tests using this species. Rotenone at 1:100,000 as a contact spray compared favorably with nicotine at 1:10,000 and pyrcthrins at 1: 7^,800 wrth Penetrol (1:200) in each spray. Hamilton and G-eramell ( 137 ) in 193^ compared the effectiveness of derris., pyrethrum, and hellebore powders against different insects. Dusts containing derris root powder (air-floated, U percent rotenone), pyreth- rum powder (l.l6 percent pyrethrins), mixtures of derris root ponder, pyrethrum powder, and hellebore powder (0..8 percent active principle) were tested. Inert clay was used as a diluent. Laboratory tests vrith • A. spiraecola showed that diluted derris powder (rotenone, 1 percent), pyrethrum powder, or mixtures of the two were effective, but hellebore was not effective. Derris powder appeared to be more effective when mixed v;ith water and applied as a spray, whereas the pyrethrum was more effective when applied as a dust. [Mixtures of derris and pyrethrum pow- ders were slightly more effecti'-e when applied as dusts than when applied as sprays.] Farrar (98) in 193& reported that extracts of pyrethrum, derris, or cube were not so efficient against A. spiraecola as nicotine mixed with oil emulsion. The addition of soap increased the killing power of an oil containing such extracts, but not enough to warrant the added cost of the extracts. Aphis tavaresi DelG. , an orange aphid Easily controlled by Derrisol 1:800 or by Katakilla 5 pounds per 100 imperial gallons of water'. — Andries (10) in 1932. 'iorslcy ( 32U ) in 193^ reported that bark of Mundulea suberosa Benth. (0.9 percent rotenone) fro r n Moa district, Tanganyika Territory, East Africa, was almost equal to derris root (5-^ percent rotenone) in toxicity to this aphid. Concentrations necessary to give 100-percent kill of A. tavaresi vrere 0.25 percent for nicotine, 0.29 percent for derris root, and 0.33 percent for Mundulea bark. Bhatta and Harayanan (15) in 1937 stated that in small-scale field trials extracts of seeds of Tephrosia Candida and of the stem bark of Mun- dulea sericea vrere effective at 0.25- and 0.5-percent concentrations, re- spectively, against A. tavaresi on citrus. Y?n der Vecht (288) in 1937 tested the method of Jones and Smith ( 180 ) using the results obtained by Vorsley with different species of derris against A_. tavaresi . This method gives good results - 18 - derris containing more than h percent of rotenone; the toxic value of Derris malaccensis (from to 2.7 percent rotenone) is "best expressed "by the following formula: Value. = rotenone content + 1/3 remainder of extract, Brevicoryne brassicae (L.), the cabbage aphid Heoton 197.5 S m - , plus an equal weight of soap in Uo imperial gal- lons of water, killed 100 percent. --Institute Physical and Chemical Research (162) in 1927. Davidson (6j, SU) in 1930 reported the following results: Concentration of s"pray Percentage of aphids hilled "by spraying with Rotenone : Racemic : Tephrosin : Toxicarol : deguelin : : 1:500 - - 1:5,000 - 1:10,000 - 1:20,000 - 1:30,000 - 1:100,000 1:200.000 100 97.^ .9^-0 • -The cabbage aphid was Used as a tost insect by Davidson and Jones (65) in I03I in studying the loss of toxicity suffered "by rotenone in certain solvents and in aqueous suspension. Rotenone at 1:10,000 killed 98.5 percent of this species. Shepard ( 2^-1 ) in 1931 referred to unpublished' work by Davidson, who found that individual tests on the cahhage aphid' with rotenone suspen- sions at 1:100,000, but treated in different ways, resulted in 89. 0, Ug.U, 6U.0, 22. U, and U6.5-percent mortality a.t the end of 1- day, but at the end of k days the same experiments, respectively, gave 95-6, 88.1, 95«5, 70.0, and 90.7-percent mortality. These data show the desirability of following the course of poisoning until the action is complete. Hamilton and G-emmell (37) i n 193^ reported that pyrethrum dust and a mixture of derris and pyrethrum were effective in laboratory tests against the cahbage aphid, while derris (1-percent rotenone) was less so. G-insDUrg and C-ranett (12U) in 1935 reported that several hundred young caDhage plants infested with the cahbage aphid were -sprayed thor- oughly on both surfaces of the leaf with a commercial -acetone extract of derris at a. concentration of 0.5 piht per 100 gallons of water plus -0.25 percent of soap. Approximately 90 _ to 100- percent kill was noted 2 days later. Houghton and Byrne in 1935 stated in a letter to the chief of the Bureau of Entomology and Plant Quarantine that they failed to control the cabbage aphid with a dust containing 2.92-percent of ether .extractives but no rotenone. Howard ct al. ( 15^0 in 1935 reported dcrris to he less effective than... nicotine for control of the cahhagc aphid. Huckett and - 19 - Hervey (157, 277 ) in 1935 reported that cabbage aphids vrere not satis- . factorily controlled by derris or cxibe du^t mixtures. The Tev York State Agricultural Experiment Station ( 212 , 213 ) in 1935 reported that derris dust (0.5 - percent rotenone) had little. value in protecting Danish cabbage against the cabbage aphid. In 193& this station reported that aphids in the cauliflower seedbed were effectively controlled with dusts containing 0.5 and 0.33 percent of rotenone, the applications being made late in the evening under calm conditions, in anticipation of ■ a period of high relative humidity during the night. Veitch ( 290 ) in 1935 reported that derris sprays are highly effec- tive for the control of the cabbage aphid. Walker and Anderson ( 296 ) in 1935 reported the following results when cabbage plants were dipped in concentrations of derris preparations strong enough to control cabbage aphids: Percentage sur\'ival of plants Material Concentration Tops Tops and roots dinued dipped Pysol 1:100 96 7^ Red Arrow - - -" - 1:100 96 95 Super Agricultural Spray 1:100 93 gl Derris dust failed to give satisfactory control. — Walker and Anderson (297) in 1935; also reported "oy Cory (277) in 1935- In laboratory tests a dust containing 50 parts of derris (3*95 percent rotenone) and 50 "^arts of gypsum caused 20-"oercent mortality in 2 days. In field experiments dusts containing 25 percent of derris proved unsatisfactory. — Kelsall and Stultz (170) in 1537. College Dibble, of Michigan State/, in advertising literature in 193^, recom- mended derris or pyrethrum dust or spray for the control of cabbage aphids. Earl-- control keeps the population low a.v.6. prevents much difficulty later. Sprays do not stick well on cabbage, and dusts are often given first choice. In large patches spraying is cheaper if good equipment is available, Gunderson ( ijM ) of Iowa State College Extension Service in I93S recommended derris or cube dust for the control of cabbage aphids. Pether- bridge and Wright (226) in I93S reported derris dusts to be inferior to a 3 percent nicotine dust for the control of the cabbage aphid. Howard and Nelson (155) in 1939 reported that a nicotine-hydrated-lime dust mixture (2.U percent nicotine) was much more toxic to this insect in southern Ohio than were dust mixtures containing 1 percent of rotenone derived from cube and containing either sodium oleyl sulfate or peanut oil as condition- ers and either talc or a mixture of equal parts of tobacco dust and sulfur as diluents. None of ,the dust mixtures containing cube gave satisfactory control of this aohid. r - 20 - f Derris or cube dusts have given unsatisfactory results in tests for the control of the cabbage aphid. — Walker and Anderson ( 298 ) . in August 1939. /-.. . Howard ( 152 ) in lQUo reported that' a nicotine-dust mixture was superior for cabbage aphid control to the rotenone-tobacco-sulfur mixture recommended for turnip aphid control in the South (cf. report on Rhopalo - siohum pseudobrassdcae , .p. U7). The Wisconsin Agricultural Experiment Station C 32I ) in 19U0 re- ■00 r ted that a mixture of derris 25 pounds, hydra.ted lime 37. 5 pounds, dusting sulfur 37-5 pounds, and nicotine (Black Leaf ^0) 5 pounds gave good control of both cabbage worms and cabbage . aphids. The sulfur kept the derris effective against cabbage "orms, even though the reaction of the mixture was sufficiently alkaline to release the nicotine necessary for aphid control. Capitophorus fragariae (Theo.), the strawberry aphid of England Rogers, King, and Mas-see ( 23b ) : in 1935 reported that, for the con- trol of _C. fragariae in England, derris sprays and dusts, nicotine dust, nnd pyre thrum spray have been tried extensively but do not give sufficient control to warrant their use commercially. Capitophorus rib is (L.), the currant aphid : The currant aphid was not controlled by a dust of enual parts of derris and hydrated lime, according to iCelsall et al. ( 169 ) in 1926. Al- though derris and soap is highly toxic to : ar>hida and similar soft-bodied sucking insects, a dry powder appears to be less efficacious. Thus a derris dust failed to control a bad attack of _C_. ribis on red currants in a garden in June 1935, but when a wet spray was used satisfactory results were obtained. Capitophorus rosarum ( Kal t . ) • ■ ; The pondered roots of four snecies of derris applied as dusts killed from 63 to 92 percent of these aphid? on roses in U days. — DeOng (75) in 1930. Foliafume (a pyre thrum— derris spray with spreader) at 1:U00 killed 91 percent in Ug hours. — Penick and Company ( 223 ) in 1936. Cavariella sp. Brittain (21) in 1925 reported that field tests to control Cavari - ella so. on ; parsnips, were made v > r ith derris (2-1/2 pounds of derris and h pounds of soap powder aer 100 imperial gallons of water) and a commercial preparation of derris, Polvo (2-1/2 pounds per 100 imperial gallons). Each reduced the infestation very little, even when soap was added. In the insectary infested leaves were dialed directly into different insecti- cides. Derris, 3 pounds per 100 imperial gallons, killed only 10. U per- cent; derris, 2-1/2 pounds per 100 imperial gallons plus h pounds McDoug- a'll's soap powder, killed 91 percent. - 21 - Cinara sa'oinae (G-illett* ft Palmer), a red cedar aphid IlcDaniel (187) in 193^- reported that this red aphid can "be controlled "by derris strays used according to the directions of the maker. Eriosoma lanigeru m (Hausm.), the woolly apple aphid The derris preparations Contraphin and Katakilla were useless against this insect. — Wahl and Muller (29U) in 1915. Gimlette (120) in 1923 reported work that H. E. Durham did with derris in 1903- Derris had no effect as a contact poison on the woolly apple aphid. Tattersfield and Roach (2oU) in 1923 also referred to unpublished results of work "by Durham, who found the woolly aphid resistant to the wet application of derris. Durham (91) in 1926 gave an interesting account of his early work with derri?, which started in the Malay States in 1902 and continued in Sngla.nd in 190^-. An extensive series of trials on the woolly aphid were carried on throughout the summer, "both with spraying and with careful use of a camel ' s-hair brush so as to get thorough wetting of the patches, which had a milky appearance '-'hen treated. The woolly aphid is difficult to wet, but in no case was there any appreciable diminution. Durham ex- pressed the opinion that, whether or not there may be a contact effect, the :nain utility of the drug must be as a stomach -ooison. -Teoton 375 g^- "l^lus 1,125 gm. of soap in Uo imperial gallons of water killed 100 percent. — Institute of Physical and Chemical Research ( 162 ) in 1927. DeOng (75) in 1930 used this as a test insect in determining the insecticidal value of four species of derris (pondered stems applied as dust). The results after 7 :0 days' exposure were as follows: Derris species Mortality Percent D. elli-otica D. trif oliata D. heptaohylla D. pol y a.ntha Check (no treatment) 100 ICO 55 Us The TT andelsmuseum of the Koloniaal Instituut of Amsterdam (8) in 1930 reported that derris was an exceptional material for control of aphids on flowers and fruits in the greenhouse, but that the woolly aphid was protected by its covering. Overley and Overholser ( 218 ) in 1932 reported that apple trees in Washington that had been sprayed with rotenone were free from woolly aphids, whereas on other plots there was a general infestation. Rotenone in oil (1:25,000) was highly effective in laboratory tests. — Turner ( 271 ) in 1932. Derris or rotenone suspensions at a concentration of 1:5,000 or 1:6,250 were effective. — DeBussy et al. (32) in 1935. Rotenone and dihydrorotenone were about eoually toxic to this species on apples, when used as a spray containing 0.1 to 0.5 percent of Agrai. At 1:5,000 r?teno-.e killed from 80 to 90 percent and at the - 22 - same concentration diliydrorotenpne killed from 65 to 75 percent. — Tan der Laan ( 177 ) In 193:;. " Eta'Dlissement-p Rotenia in 193^, in a. letter to R. C. Roark, stated that this species is repelled by a proprietary product containing 12 "oer- cent of cube of 6 percent rotenone content. Hyalopterus arundinis (F.) (H. pruni (F.)), the mealy plum aphid Garman ( ll6 ) in 1928 reported experiments made in Connecticut with insecticides offered as substitutes for nicotine sulfate. Cne of the commercial preparations of derris was tried in I927 against the mealy plum aphid and showed good killing power. It vas evident that soap or casein lime was needed in combination. The product investigated did not mix well with lime-sulfur solution of winter strength. Tests with commer- cial preparations of derris and pyrethrum against the mealy plum aphid g ve the following results: Material Dilution Mortality Percent Derris ^reparation ----- 1 11.. to 100 gal. - - - - 88. 3 Do - r 2 lb. to 100 gal. 97.6 Fyrethrura soap - - - - - 53 11. to 100 gal. - - - - 9-.U ITicotine sulfate l" lb. to 100 gal. 92.2 Chec 1 :, no treatment ----- — ____ q Derris 01 1:6,250 were e or rotenone suspensions at a concentration of 1:5,000 or ffective. — DeBuss'y et al . (^0) in 1935. Hystercneura seta.riae (Thcs.), the rusty plum aphid Farrar (98) in 193 6" reported that extracts of pyrethnim, derris, or cube '-'ere not so efficient against H. setariae as was nicotine mixed with oil emulsion. The addition of soap increased the killing nower of an oil containine," such extracts, "but not enough to warrant the added cost of the extracts. Macrc siphoniella, s ar.-'oorr.i (Gill.), the chrysanthemum aphid Derris dust was effective. — Mclndoo and Si even ( 188 ) in I92U. Ginsburg and G-ranett ( 12U ) in 1935 reported res. Its with a commer- cial acetone extract of derris. This extract contained 5 percent of rotenone and 16 percent of total extractives. About 2,000 chrysanthemum plants infested with M. sanborni were sprayed with the commercial acetone extract of derris at dilutions of 1/3 pint to 100 gallons of water and 0.2 percent of coccnut-oil soap. Observations 2 days later showed practi- cally 100-percent- kill of this insect. Macro si~ohum liriodendr i (Men.), the tulip tree aphid Mclndoo, Sievers, and Abbott ( I89 ) in 1919 reported that the alco- - 23 - holic extracts of various species of derris plus soap were effective against this aphid. Derris applied as a dust killed 92.3 percent. In I92U Mclndoo and Sievers ( 188 ) reported the cold alcoholic extract of cube used vrith soap to "be effective. A dust of 2 parts of rotenone and 98 parts of diatomaceous earth killed 68. ^ percent of these aphids on a tuliptree. — Davidson (63) in 1930. Macro siphum pisi (Kalt.), the pea aphid Cory (53, 5U) reported in 1923 that lime to which 5 percent of Derrisine was added, used at the rate of 50 pounds per acre, killed only 10 percent of ( Illinoia ) Macro siphum pisi . In 193^ he reported that rotcrione "Vast was especially efficient in the control of the pea aphid. Rockwood and Chamberlin ( 235 ) in May 193^ reported on the action of derris dust on the pea aphid at Forest Grove, Oreg. Austrian field peas infested by aphids were dusted on April l6 with derris dust contain- ing a silica filler, the rotenone content "being 0.5 and 0.7 percent. The naximum reduction of aphid? in the best parts of these plots was not over 50 percent and nothing approaching practical control was obtained. Dudley (oU) , of the Madison, Wis. , laboratory of the Bureau, in December 1935 reported insecticide tests against the pea aphid. After the pea vines became heavily infested, the application of derris sprays containing 0.01^8 percent of rotenone reduced the aphid population ap- proximately 95 percent, in comparison with the untreated plots, and re- sulted in a profitable yield of peas. Most of the derris sprays were applied with commerci-lly prepared sulfonated phenyl phenol (1:600), which functioned as a spreader and wetting agent. In comparative tests vrith this agent, sodium lauryl sulfate (1:1,500), and sodium oleyl sul- fate (1:d00) no significant difference could be determined in the perform- ance of the three materials. Derris sprays without spreaders or wetting agents caused slower but eventually as good reductions in aphid popula- tions as when spreaders a^id wetting agents were used. Derris dust contain- ing 0.5 percent of rotenone applied in a heavy infestation gave erratic results, inferior to those from the derris sr>rays. Bronson (22, 2J, 2U-, 25, 26, 27) in IQ36 reported the results of greenhouse tests of derris against the pea anhid made at Madison, Wis. Tests in vrhich aphid-infested plants were treated with various dust mix- tures, and placed in a chamber where the relative humidity remained at approximately 100 percent for a period of l6 hours after treatment gave much more effective control than in com-narable tests in which the dusted plants were left in an open greenhouse. Derris-dust mixtures containing 0..U percent of rotenone, with talc as the diluent, plus sodium oleyl sul- fate as a conditioner, were more effective in greenhouse experiments than were derris-dust mixtures with kaolin or gypsum a* the diluent, plus sodium oleyl sulfate as the conditioner, when the plants were left in the open. When treated plants were placed in a moist chamber, where the •prevailing relative humidity was approximately 100 percent, no significant differences could be*detected between the performance of each of the three dust mixtures with different diluents. Better results were obtained with derris-dust mixtures containing a conditioner (i.e., sodium oleyl sulfate special) than with the unconditioned dust3. During the winter of - 2h - 1935 potted pea slants were sprayed with derris and later infested with aphlds. -The spray 'consisted of 'ground derr-'is; '-root i^.2 percent rotenone and 13 percent total .extractives) used at \a 'dilution to .'obtain O.0115 percent of rotenone '{3 pounds per -i'OO ga'llons'Adf ":water) and one of -two spreaders and wetting : - agents j either 'a 7 sulfated'butylated diphenol [Aresket -2^0] at a dilution'-of l:600 ; of-^ tt®"^percent'- aqueous solution, or a sodium oleyl sulfate, special, at the dilution of 1:1,000. Small, uninfested potted pea plants were sprayed thoroughly, allowed to dry for 2U hours, then lightly infested with third and fourth 'pea aphid instars, and. arpperly caged, there being an average of four plants to the pot. ' Bronson concluded that derris spray, containing either of the two spreaders and wetting agents used in these .experiments, protects potted pea r plants artificially infested with the pea aphid for a period of 7 days against any "building up of the original infestation. . . In' 193b Bronson described a hall mill for mixing cube or derris powder' with a diluent and with an activator or conditioner. These dusts have proved to be toxic against the pea aphid and it is believed that - thorough mixing greatly increased their effectiveness. In 1937, he .des- cribed an irrir 1 oyed apparatus for mixing derris or cube powder .with a diluent and a conditioner. One hundred pounds of dust containing 1 percent of rotenone for use against the pea aphid is made ''oy mixing 25 pounds of derris. or cube root powder (^ percent rotenone), 72 pounds of. talc or other suitable diluent, 1 pound of conditioner (wetter and spreading agent), and 2 pounds of water. Satisfactory conditioners are sodium oleyl sulfate and an alkylphenylbenzenesulfonic acid. Tests were made in a greenhouse at Madison, Wis., with different spreading, wetting, and sticking agents used with derris sprays against the pea aphid. A commer- cially prepared product containing a sodium oleyl alcohol sulfate was the most effective agent used with derris, and resins or other adhesive agents were not effective in protecting the active ingredients of derris from loss either through decomposition or from being washed with a water spray.' The pea plants vere first sprayed with a derris solution contain- ing one of the spreading, wetting, or sticking agents. Some of these- treated plants were hand-infested ?}\ hours after they had been sprayed: others were washed twice with water and inf-ested 5 days after being sprayed. The results showed some residual effect of -derris in all the- tests in which plants were infested with the pea aphid 2U hours after being sprayed, but probably no residual effect of derris was apparent in the' plant? washed twice after being sprayed,, and then infested with the pea aphid. In July I93S Bronson issued revised directions for mixing rotenone dusts (see 26) -in a cement mixer. The derris or cube root powder should be of such p. degree' of fineness" that not less than 90 percent of it will pass through' a 200-me-sh sieve and all the material (100 percent) should pass through an SO-mesh sieve. The talc or other diluent used should be of such a' degree., of fineness that .all the material will pass through a 300-mesh sieve." . Tn most of '.'the experiments and field tests against the pea aphid thus far, a sodium oleyl sulfate (Avirol, IIT-U3S ) was used and proved satisfactory.. Other proprietary conditioners also proved satisfactory. Dudley, Br'p'n'son,' and Carroll (87, S3, g£) in 1936 reported the - 25 - results of tests made in 1935 at Madison with derris (rotenone 3.7 per- cent total carbon tetrachloride extractives l6.1 percent) against the pea aphid. Three series of experiments were conducted: (l) In a green- house late in the winter and early in the spring, (2) in the field during the normal pea-growing season, and (3) in the field late in the season on late-planted peas. The greenhouse tests demonstrated that ground derris as a sr»ray applied at the rate of from l-l/2 to 5 pounds per 100 gallons of water (0.006 to 0.022 percent rotenone), with a spreader and wetting agent, killed nearly 100 percent of the aphids on the treated plants. The aphids died throughout a period of from 3 to 5 days , and practically no reproduction occurred in the interim. Many summer field tests on both small and large plots demonstrated that around derris as a spray, applied at the rate of from 1/k pound to 5 pounds per 100 gallons (0.0009 to 0.022 percent rotenone), with a spreader and wetting agent, killed more than 90 percent of the aphids on the treated plants; that from 3 to 5 days were required to obtain the maximum mortality; and that little or no reproduction occurred during that period. In these tests the application of derris sprays increased the yield of shelled peas approximately 8S percent over that of untreated checks. A large number of tests on late-planted peas revealed that derris as a snray, with a spreader and v/etting agent, applied prior to aphid infestation protected the plants from appreciable damage for several weeks and resulted in an ultimate infestation considerably lower than that in the untreated checks; that heavy applications of derris sprays after the incidence of an infestation protected peas from damage from a commercial standpoint for nearly a month, enabling them to produce a normal crop of pods; that heavy applications of derris sprays with any one of several spreaders and wetting agents, made after the infestation had become heavy, killed approximately 95 percent of the aphids; that derris sprays controlled the aphid more ouickly and to a higher degree than did derris dusts (rotenone 0.^- percent); and that concentrations of derris as low' as lA to 1/2 pound (0.0009 to 0.0019 percent rotenone) per 100 gallons, with spreaders and v/etting agents, killed approximately as large a percentage of aphids as did 3 pounds per 100 gallons. Wetting and spreading agents tested included a pine-oil product, diphenyl butyl sodium sulfonate, sodium lauryl sulfate, and sodium oleyl sulfate. In 1Q37 the ^-ame authors summarized the results of field experi- ments with derris and cube against the' pea aphid. Dusts tried included derris powder plus talc, cube powder plus talc, and derris powder plus talc and sodium oleyl sulfate, all diluted to a content of 1 percent rotenone. In order to be effective a spray of cube or derris should con- tain at least 0.005 percent of rotenone. The dusts were applied at the average rate of U6 pounds per acre; the sprays, at the average rate of lUU. gallons per acre. Increases in yield from five dusting tests ranged from 59 to 2U0 percent and averaged 138 percent. Increases in yield from three spraying tests ranged from 96 to 109 percent and averaged 101 per- cent. A limited number of tests indicated no difference between the effect of derris snd^ of cube sprays. In the sprays various wetting agents were tried, including b>utyl diphenyl sodium sulfonate. In comparable dusting tests the special derris-talc dust -was appreciably better than - 26 - the regular dust in reducing the infestation on entire plants, "but "both dusts were equally effective in reducing the infestation in "blossom clus- ters. This special derris-talc dust was made "by atomizing into the derris- talc, while it was "being mixed, a solution composed of 1 percent of a sodium oleyl alcohol sulfate and 2 percent of water. Considering "both spraying and dusting tests together, the special derris-talc dust appeared slightly "better than the sprays in reducing the infestation on entire plants. Dusts and. sprays reduced the infestation in "blossom clusters eoually well. These results were referred to "by Roark (2^0 in his re- view of the comparative value of derris and cube. Bronson and Dudley (28) in 193& reported on conditioning agents for increasing the effectiveness of rotenone-bearing dust?- against the pea. aphid. They concluded that, in botrh the greenhouse and the field, derris- or cube-dust mixtures conditioned with a spreading and wetting agent have been shown to be superior, as insecticides against the pea aphid, to plain derris- or cube-dust mixtures. Under field conditions this superiority of the conditioned dust mixtures has amounted to approx- imately 12 percent, which may be the difference between satisfactory and unsatisfactory aphid control. In general, conditioned derris- or cube- dust mixtures reinforced by the addition of nicotine or an aliphatic thio- cyanate have been superior to conditioned dust mixtures. Field data indi- cated that derris and cube -were equally effective against the pea aphid. Dudley and Bronson (8_5) reported results of experiments against the pea aphid in southern Wisconsin in 1938, wherein dust mixtures and sprays containing rotenone, as well as nicotine vapor, applied to large- scale experimental plots, indicated that all these insecticides resulted in an increase in yield, as compared with the untreated check plots, and that, owing to the conditions of pea aphid infestation existing that year, there were no outstanding differences between these treatments. From the 19^8 work against the -oea anhid they concluded that, even with excellent growing conditions and a light aphid infestation, an adequate financial return was obtained by treating the peas with the above-named insecticides. Dudley and Bronson also reported ( 222 ) that in a large replicated- plot experiment satisfactory aphid control was obtained by treatment with derris spray, derris-dust mixture, and nicotine vapor, but not with nico- tine dust. The largest increase in the yield of shelled peas resulted from the derris-dust treatments, with the nicotine-vapor treatment second, and the derris-spray treatment third. The plots treated with nicotine dust yielded less than the checks. Derris spray was used at a rotenone concentration of 0.01 percent plus sodium oleyl sulfate and in some cases also 1 percent aliphatic thiocyanate. In February 1939 Dudley and Bronson (So) reported that an analysis of the wind velocities at the experimental plots at Waunakee, Wis., during the 2 , -'-hour period of each day during June for the 3 years 193^-3^ showed that on an average during this period, when dusting operations against the pea aphid are usually performed in Wisconsin, there was a total of 6? hours of daylight when the wind velocities ranged from to U miles per hour, as compared with a total of 223 nocturnal hours when the wind was in the same velocity range. It is within this velocity range that dusting operations against the pea aphid can be most effectively performed irifunmm— tsamm - 27 - under Wisconsin conditions. The analysis demonstrated further that the wind velocities remained within a range of from to h miles per hour for consecutive oeriods of 3 hour's or more at a time approximately two and one-half times as often during the night as during daylight hours. These data indicate the desirability of applying dust mixtures for nea aphid control during the night, whenever conditions will permit. Bronson and Stone (29) in I93S reported that, in an extensive series of greenhouse tests with several combinations of derris-dust mix- tures against the pea aphid, a derris-dust mixture containing Q.k percent of rotenone, with talc as the diluent and conditioned with sodium oleyl sulfate as a wetter and spreader (1 percent), plus a crude peanut-oil emulsion (2 percent), gave a satisfactory mortality of the pea aphid through all the ranges of relative humidity from 20 to S5 percent. The application of dorris-dust mixtures that did not contain any conditioning materials resulted in a low mortality of the pea aphid at all the ranges of relative humidity encountered. The application of derris-dust mixtures containing sodium oleyl sulfate (1 percent) as a wetter and spreader, but without crude peanut-oil emulsion, gave a low mortality of the iaea aphid at lev; relative humidity and a satisfactory mortality of the test insects after the expiration of U days in instances when the relative humidity was 50 percent or higher. It was concluded, on the basis of these tests in the greenhouse, that derris-dust mixtures containing the sodium oleyl sulfate as a wetter and spreader were decidedly more toxic to the pea aphid than a dust mixture not containing this ingredient; whereas the dust mixture containing this same wetter and spreader, plus a crude peanut-oil emulsion, was greatly superior to the dust mixture that did net contain this vegetable oil. These results corroborate pre- viously reported findings of Howard and Fulton, of the Columbus, Ohio, laboratory, that the addition of peanut-oil emulsions to sprays or dust mixtures greatly increased their efficiency against large plant bugs. If the results of these greenhouse tests are borne out under field condi- tions the effectiveness of dust mixtures containing rotenone for use against the pea aphid may be increased greatly by the addition of peanut- oil emulsion; but thus far results in the field have varied with humidity. The Secretary of Agriculture (27*0 in his 19 7 6 annual report wrote as follows: Laboratory and field tests with organic insecticides, particularly derris and cube, have brought many modifications in the recommendations for the control of certain insect nests. It has been demonstrated that these insecticides, which do not leave residues objectionable from the standpoint of human»health, can be effectively used against a number of different truck-crop pests. * * * The further usefulness of these recently developed materials is evidenced by the determination that one application of sprays or dusts of derris or cube is effective against the pea aphid over a longer period than other recommended material, such as pyrethrum and nicotine. This statement also appears in the Yearbook of the Department of Agriculture (29£) for I937 . - 28 - White (305) in April 193^ issued suggest ions en the Use, of derris sprays for -control of the pea aphid. Tor this purpose derris should con- tain k percent of : rotenone and he used at the rate of 2 pound? per 100 gallons. At least 150 gallons of the spray should he applied per acre under a pressure of not less than 250 pounds, when the plants are dry. A wetting agent should be used at the rate of about 1/2 pound dry veight per 100 gallons of water. Sodium lauryl sulfate and sodium oleyl sulfate are suggested a;- suitable wetting agent?, and a sulfated phenylphenol at 1:1,500 (dry basis) has been used successfully. The New York Agricultural Experiment Station ( 213 , 21>) in I936 reported that derris was being tested for the control of the pea aphid. In 1937 this station stated that rotenone sprays, properly applied with adequate, equipment-, pre.'"". v effective in killing the pea aphid, but that rotenone dusts had net been tested in . the field sufficiently to bring out all their possible limitations. The United States Department of Agriculture, Bureau of Sntcmology and Plant Quarantine (278) in its annual report for 1 Q 35 stated that the pea aphid caused heavy losses to the pea growers in Wisconsin, Kew York, and Ohio. The investigations consisted -primarily of fi-ld-plot tests with several insecticides and, while the results to date are only pre- liminary and cannot be used re. a oasis for recommendations on pea. aphid control, the indications are that a derris-powder sora.y may be useful against the pea aphid. The Bureau of Entomology and Plan^c Quarantine (280) in its annual report for 13 7 b stated that encouraging results in the control of the pea aphid wre obtained in 1935 with sprays containing derris, end special field experiments were conducted with derris sprays and derris dusts in California, Florida, and Virginia late in the winter and in the spring of 1939* J ~ r - r results of these field tests indicated that derris sprays were effective in controlling the pea aphid and that, under favorable condi- tions, ins idss containing rotenone- the active ingredient of derris and cube, had -• r°sidua.l effect that protected the treated plants from severe damage for an extended -neriod. It was determined that, in general, sprays cr dusts containing nicotine have a '/ore repid actioa against the pee. aphid than insecticides containing rotenone, but the latter hrve a much longer residual effect. This residual effect of rotenone-containing insecticides,, as observed in field tests, was substantiated by laboratory studies. Continued field work late in the spring of 193^ derr^nstrated that a derris dust containing a specially ^erepa.r r d spreading agent yielded result'- comparable: to those from a derris spray, the dust being prepared by atomizing a sodium oleyl sulfate into the derris-dust mixture While it was being revolved in a. steel-drum ball mixer. The Bureau ( 281 ) in its 1 G 3? annual report staged that cube or derris dusts plus sodium oleyl sul- fate are effective against pea aphids and leave no rcterone or other con- stituents in peas taken from treated plants. In its 193? annual report the Bureau ( 283 ) gave the results of much work with rotenone products. During the springs of 193 7 ar -d 193? ^ ae P ea aphid was particularly trouble- some in Maryland, Delaware, end New -Jersey. Investigations were continued in Wisconsin on the central of this u r st. In these control t^sts emphasis was placed on the time of tr.:atm~nt for maximum benefit in protection of the crop. Field and laboratory t~sts were continued with derris and cube . • -29-. , -duets and sprays and the. results showed that these materials, applied either as spray or dust, appeared to "be the most satisfactory ones devel- oped thus far for the control of this aphid. Adequate spraying or dust- ing equipment is essential to aphid control, as is proper material and time of treatment. In 1939 the Bureau (2J35) reported that insecticides containing rotenone had proved effective In 1938 the Bureau (282) published suggestions for the control of the pea aphid, prepared "by a committee of entomologists at the annual meeting of the American Association of Economic Entomologists at Indian- apolis, Ind. , on December 27, 1937. The following recommendations were based on observations and data accumulated from experimental work done east of the Rocky Mountains: Satisfactory control of the pea aphid has been accom- plished by several methods. These include, without sugges- tion of preference (l) dusting, (2) use of nicotine vaporizer, and (3) spraying. Success in the use of any of these methods will depend entirely upon adeauate and efficient equipment and properly timed, thorough application. (l) Busting with derris or cube : Field experiments with derris or cube dust mixtures containing talc or other suitable carriers, condi- tioned with a liquid spreading and wetting agent, have re- sulted in satisfactory control. Such dust should contain approximately 1 percent of rotenone. In applying these dusts the boom should be completely enclosed and a trailer 25 feet or more in length should be used. Dusts should be applied at the rate of 35 to ^0 pounds per acre. The speed of the machine should not exceed 3 miles per hour or 300 feet per minute. Dusting is much less effective when the wind velocity exceeds 8 to 10 miles per hour. Spraying is an effective method of control, but its economic usefulness is conditioned by the nearness of an adequate water supply. On the basis of ground derris or cube root containing U percent of rote- none, 3 pounds should be used per 100 gallons of water, with corresponding dilutions where the content is greater or less than U percent of rotenone. A spreading and wetting agent, in either liquid or dry form, is necessary. The application per acre should be from 125 to 200 gallons. Pressure should be from 225 to 300 pounds, and depends on size of disc aper- tures, type of nozzle, and pump capacity. An infestation of 35 aphids per sweep of a standard collecting net, for an aver- age of 5 sweeps in different parts of the field, usually indicates that treatment should be begun. The Bureau in February 1938 distributed a summary of the remarks made at the Pea Aphid Conference ( 222 ) at Indianapolis, Ind., in December 1937. Shropshire of Illinois reported on the efficiency of the numerous wetting agents offered for use with derris and cube. Over 50 of these combinations and dilutions were tested in replicated plots, and it was found that some of the best wetting agents were the poorest for use with derris or cube for aphid control on peas. Results of experimental work in 1937 tended to verify results obtained in 1936 with both nicotine and derris or cube for pea aphid control. They further show that cube is as - 30 - effective as derris, assuming that the rotenone and total extractives are approximately the same in Doth samples. Derris or cube with a rote- none content of U percent was effective for pea aphid control when used at the rate of 2 or 3 pounds per 100 gallons of spray, assuming that the spray was applied at the rate of 125 to 150 gallons per acre. Aresket (liauid) used at the rate of 1 to 600 was used as a standard for compari- son with other spreaders. An extensive set of dust trials was planned for 1937 following limited work in 1936. Most of the dusts were made up to contain 1 per- cent of rotenone, other ingredients "being varied as desired. Variables included diluents, wetting agents, some suggested by Dudley and Bronson, and irritants such as nicotine and certain thiocyanatos. Results with rotenone-bearing dusts varied in 1937, as in 193&. * n many instances the results were excellent, but in certain experiments they were unsatis- factory. Apparently the poor performance was due to some weather condi- tion, such as absence of free moisture (dew or rain) on the plants, Hot- withstanding some very poor results obtained with rotonone-bearir.g dusts, it is believed that they have sufficient merit to warrant recommendation with reservation. The use of wetting agents or irritants in dusts for use on peas was not recommended. A committee of entomologists representing a number of the State experiment stations and the Bureau of Entomology and Plant Quarantine, of the United States Department of Agriculture ( 279 ) » a * the December 193^ meeting of the American Association of Economic Entomologists at Atlantic City, issued the following suggestions for control of the pea aphid: Dusting with derris or cube: Preliminary experiments with these materials, with a carrier such as talc, conditioned with a spreader and wetting agent, have given satisfactory control. Their use is suggested only on an experimental basis. Such dust should contain approximately 1 percent of rotenone. Spraying with derris or cube: On the basis of ground derris or cube root containing U percent of rotenone, 3 pounds should be used per 100 gallons of water. Corresponding dilu- tions should be used with derris or cube containing more or less than h percent of rotenone. A spreader and wetting agent is necessary. The application per acre should be from 150 to 200 gallons. Pressure should not be less than 300 pounds. Cory and Graham (5_5) in 193^ reported that derris without a spreader gave poor control of the pea aphid, but with sodium lauryl sul- fate good control was obtained. Ten pounds of rotenone material (0.009 percent rotenone in the finished spray) plus 1/2 pound of sodium lauryl sulfate were used to 100 gallons of spray. Rotenone remained effective against the aphids longer than did nicotine and soap. One year's experi- ence in Maryland with rotenone (without spreader) showed a slight decrease in aphid infestation and no increase in yield of peas, over the unsprayed plots. The next year's experience with rotenone (with spreader) showed - y- - a decrease in aphid, infestation in plots that had an initial infestation and an increase in yield of peas ranging from 123.3 to ^O^-.O percent over the unsprayed plots. The highest yields, however, had no initial infestation. Graham (130 ) in 1937 reported that in 1932 Pyrote (a pyrethrum- rotenone product) , 1 gallon to U00 gallons of spray, gave an 89-72 per- cent kill of pea aphids in Maryland. In 1935 in the same field where the nicotine and soap tests were conducted, plots of the same size were laid out and a 3 percent rotenone-derris dust, without a spreader, at the rate of k pounds per 100 gallons of spray, was applied at the same time as the above-mentioned nicotine spray. Records were made on yield and aphid infestation. The results showed a slight decrease in aphid infes- tation and no increase in yield of peas over the check plot. In 1936 derris plus sodium lauryl sulfate was tested. Plot 5 re- ceived one application of derris dust containing 0.75 percent of rotenone at the rate of 10 pounds plus 1/2 pound of sodium lauryl sulfate spreader to 100 gallons of spray at the "beginning of the "blooming period. This plot produced lh2 pounds of shelled peas per acre, an increase of 128.3 percent over the check. The aphid infestation "before the peas were sprayed was 15 per tip "but 2k hours after the peas were sprayed it was only 2 per tip. Plot 7 received one application of derris dust containing rotenone at the rate of 6 pounds (active derris extractive material, including rotenone, 8 percent) plus 1/2 pound of sodium lauryl sulfate spreader per 100 gallons of spray. This application was applied 10 days before the peas "began to "bloom, and produced 1,128 pounds of shelled peas per acre, an increase of 2H7 percent over the check plot, llo aphids were present when the spray was applied but 12 days later the infestation averaged 0,5 aphid per tip. Plot 8 received two applications of a similar derris dust, the first 10 days before blooming started, the second when the peas "began to bloom. The yield in shelled peas per acre was 1,63s pounds, or an increase of kok percent over the check. !"o aphids were present before the first application nor 2 days after the second. Plot 9 received one application of derris containing rotenone, the same strength and spreader as in Plots 7 and 8. Application was made when the peas first came into bloom. The yield in shelled peas per acre was 817 pounds, or 151.3 percent increase over the check. The aphid infestation just before the spray was applied was lU per tip, but 2k hours after the application it was 7 per tip. At harvest time the rotenone-treatcd plots were green and succu- lent and the pods well formed and tender; whereas check plots and nicotine- sulfate-treated plots were practically dead and the pods poorly developed. Another index to the efficiency of derris dust containing rotenone over nicotine sulfate was the number of aphids on the ground after harvest. Under the derris- rotenone- sprayed plots only an occasional aphid could be found on the plot that received two applications, and a few more on the plots that received one application, whereas under the nicotine- - 32" - sulfate- sprayed plots and check- plots the ground was literally alive with aphitis., The rotenone remained effective against the aphids over a much longer period than did nicotine sulfate and soap. Graham and Ditman, of Maryland, (228) reported that in 1937 derris and cube sprays, when properly applied, gave good results. Fie o tine fumigation the most complete and quickest kill. Derris dusts, pos- sibly "because of improper application, seemed less effective than sprays. Derris powder (8-percent total extractives?) was used at the rate of .?. or 4 pounds per 100 gallons, plus sodium lauryl sulfate (3/4 or 1/2 pound) or Orthex Spreader (1 pint) as a wetting agent. Ditman (Si) in December 1939 reported on the practical aspects of pea aphid control.; Busting with 0UD5 or derris (l percent rotenone) was probably the most commonly used treatment for the control of the pea aphid 'oy Maryland growers. Only a very small acreage was treated with the nicotine vaporizer and no nicotine dust was applied. The evidence from the observations on experimental and commercial treatments indicate that cube sprays were not so efficient as derris sprays for pea aphid control and that the additional cost of derris over cube will probably pay good dividends. Observations on commercial control indicate that derris is better than cube and that a' derris dust of 1 percent-rotenone content should be used by those who prefer dusting to spraying. All dusting should be done at night when the air is still and when vines are heavy with dew. Ditman, Cory, and Graham (?2) in August l c i39 reported tests on the control of the pea aphid in Maryland in 1938- The following were tested as sprays: Derris + Areske't (rotenone 2.6 percent); cube: cube plus Vat sol CS (rotenone 3«2> percent); Agicide (1937 pack, stated to con- tain 1 -percent rotenone). The derris and cube were used at the rate of 4 pounds per 100 gallons. Agicide and derris gave a greater reduction of aphids 'oer sweep and per tip than did cioe. Agicide gave a slightly higher kill of aphids than either derris or cube and derris gave- a. better kill than cube, by all three of the, methods of population estimation. Further examination- of the results shows that the treatments held the aphid population in check for a period cf approximately 10 days, though the percentage of infested, tips increased slightly in plots treated with Agicide and cube, derris remaining about the same. This increase in the number of tips infested after spraying tends to discount the idea of any residual effect of the spray. ' In the severe and extended infestation of the pea aphid of 193^, one application of insecticide was*. not sufficient -to obtain -good control.. There was little difference in yield of nlots receiving a single early ' q rp application of cube and those receiving a si nglby application, as neither treatment .gave satisfactory control. The number of aphid? per sweep, aphids per tip, and the percentage of tips infested were satisfactory indices to the degree of control obtained by various spray treatments. Sometimes, however f counts of all p,phids on entire plants showed that the above estimates of populations indicted a greater percentage reduc- tion than actually occurred. ' ■■■■'' JW'l W H - 33 - Graham ( 131 ) in 1939 recomrr.ended the following for control of the pea aphid in Maryland: Spray . — Three pounds of micronized cube or derris (U- percent rotenone), plus spreader, to 100 gallons of water at 150 gallons per acre and 500 pounds pressure. Dust. — Finely ground derris or cub^ (0.75 - to 1.0- percent rotenone) at 35 to Uo pounds per acre. The machine should not exceed 3 miles and the wind velocity 8 or 9 miles per hour. Rotenone-hearing materials used as sprays give satisfactory control of the pea aphid when timely and properly applied. Rotenone-bearing dusts are equal to rotenone sprays in reducing aphid infestation under extremely hot and dry conditions. The first application should he made when the aphid infestation is 10 per sweep of the net, with another application 10 days later if the infestation increases. Graham and Cory (132) in August 1939 reported that recent experi- ments, consisting of large field plots, on the control of the pea aphid in Maryland indicate that rotenone-bearing materials have great possi- bilities in pea aphid control. In 193& plots sprayed with derris contain- ing 2.9 percent of rotenone gave a maximum increase of hoU percent yield over unsprayed plots. Further tests with rotenone-bearing materials in 1937 ?nd 1938 confirm, in general, the results obtained in 1936. In 1937 and 193s tests were made with — Derris (rotenone 2.9 percent) 2 or U pounds per 100 gallons + sodium lauryl sulfate l/U or 1/2 pound per 100 gallons Ditto, h pounds per 100 gallons + Orth^x spreader (1:800) Ditto, 1 pound per 100 gallons + nicotine sulfate 1:3200 + soap 1:1600 Derris (rotenone 3»S percent) 3 pounds per 100 gallons Agicide 1:200 Bor.ide (rotenone 2 percent) 1:300 Cube (rotenone U.U percent) 3 pounds per 100 gallons -+ sodium lauryl sulfate l/U pound per 100 gallons Fixed (stabilized) derris 3 pounds per 100 gallons Dust containing 0.75 percent rotenone. The authors concluded that 3 ye^rs of experience with derris as an insecticide for pea aphid control in largj field plots indicated that when the application is timely and thorough the results are satisfactory. One year's experience with cube in comparison vrith derris indicated that, even though the rotenone content of cube is higher than that of derris, the latter gives better control. Several years of experience on the tim- ing of sprays for per. aphid control show that the best results are ob- tained when the aphid infestation is not greater than 1 per tip or 10 per sweep when the first application is made. If the- first spray is - 3U - applied 6 or 8 days before blooming, a later application is likely tr "bo necessary. One year of experiments with rotenone (cube) dusting- showed it to be inferior to rotenone sprays. In general, dusting was less ef- fective than spraying. Howard and Mason (155) i n 1937 summarized information on the use of derris and cube sprays and dusts-. It nay be necessary to use a dust containing 1 percent of rotenone in the control of the pea aphid. A spray containing 3 pounds of derris or cube powder (U percent rotenone) is effective. A wetting agent is necessary. Knowlton and Soronson ■ U~ l ) in April 1937 recommended derris or cute (U percent rotenone) at 3 pounds per 100 gallons of water applied at a pressure of at least J>00 pound? for the control of the pea aphid in Utah. To be most effective such a spray should be applied or. a ouiet, warm day and before the pea aphid cause?, noticeable injury tc the plants. • The Maine Agricultural Experiment Station (1^0) in 1^37 discussed the use of rotenone against pea aphids in that State. Reference was made to the use of highly concentrated' rotenone or of nicotine in a. liouid base f the base often being a light, highly refined oil, and to their distribution from airplanes. Preliminary experiments with hand apparatus strongly indicated that an effective wetter and spreader is necessary for satisfactory cortrol. The percentage of rotenone, the fineness of materials, the presence of an effective adhesive wetter. or .' spreader, thoroughness of apnlica.tioa, proper timing of application of the insecticide in relation to the presence of aphids on the peas, and weather conditions all may influence the effectiveness of the dust or spray. Observations in Main* during the last 3 years have led to the conclusion that the stage of growth of the pea. T ~ines is an important con- sideration in timing the sprays. If aphids are present when the pe-^s are in bloom they are a potential threat to the -crop. Rotenone applied then will remain effective for about a week, and under Maine conditions a sec- ond application is rar ly necessary. -:. Agricultural Experiment Station ( 217 ) in 1° 7 7 reported that preli Lnary observations indicate the rot- : _ one- b paring sprays to be of value ir com! ti - the pea aphid. Tr. ■ nicotine sulfate, soap is also of value but its effects do not appear tc last as long as these of the roter.one-b; aring sprays. Various new spreading' and wetting agents were also used. " l.^er (2°:) in 1-17 reported that 1/2 pound of Ultravet added to 3 pound? of cube (4 percent rotenone a'nd 1- percent total Extractives) in 100 gallons of water increased the control of the nee aphid from 93 • 5 to 9S.7 percent, and 1 pound of Ultrawet plus 7 pounds of cut'" gave a control 0"^ 98.8 percent. Cra.ufurd-?enscn (3 7 ) in l c 7? reported that o ?. aphids were reared in a greenhouse under standard conditions and used for the laboratory testing of liquid contact insecticides, especially derris preparations:. The result?- of trials or. en" cne lay were comparable and indicated the comparative toxicities of the insecticides tested, but when the same insecticide was tested on different "".ays the results were incoordinate. W \ \ - 35 - When nea aphids were collected in the field the results were completely unreliable. Dunlap and Turner (90) in 1938 recommended cube of U percent rotenone content, k pounds per 100 gallons, with a spreader such as Ultra- wet (1/2 pound) or Areskap (6 ounces) for combating the pea aphid. Gunderson ( ljU ) in 193^> recommended derris against pea aphids. Xnowlton, Smith, and Harmston ( 172 ) in I93S reported on the control of the pea aphid in northern Utah in 1937- "Vano burner" mixture (nicotine ) fumigation gave about 99 - P erccn * control. Sprays . — Agicidc semifluid spray concentrate was used as a. suray at dilutions of 1:50, 1:100, 1:150, and 1:200 with good pea aphid kills, even under hand-sprayer conditions. An analysis of the data indicated that there was no significant difference between the four concentrations supplied. Spray tests with derris and cube used at the rate of 3 pounds of a U-percent rotenone-bearing dust to 100 gallons of water, to which. Lethane spreader was aided, gave eaually good results, there being no significant difference between these and the Agicidc sprays. Use of higher concentrations did not appear to be justified by the results obtained. Dusts . — Applications of 1-, 2-, and 3-p^ r cent rotenone-bearing Derricide produced rather heavy kills of the pea anhid, comparable in effect to the spray applications listed above. Agicide 1-percent rotenone dust usually gave good results. Applications of a 0. 5-percent rotenone dust did not give significant control. Knowlton, of Utah ( 222 ) , reported that in 1°37 ground cube and derris root gave good control as a spray when diluted at the rate of 3 pounds of U- percent rotenone-bearing dust (or equivalent) to each 100 gallons of water, to which a linuid spreading and wetting agent was added. "Agicide" semifluid spray concentrate also was effective, no significant difference in control being noted between applications at strengths of 1:50, 1:100, 1:150, and 1:200. Cube- and derris-du^t mixtures containing from 1 to 2 percent of rotenone usually gave rood control, but the re- stilts were less consistent than with the derris- and cube-spray treatments Parks and Pierstorff (21_9) in 1933 recomnended rotenone spray for the control of the pea aphid on peas. They stated that a little Kayso or pondered skim milk should be added as a spreader. Stearns ( 251 ) in 193S recommended nicotine sulfate dust or a spray of derris or cube for the control of the ;ooa aphid in Delaware. The dust should be applied under a trailer 100 feet long, made of air-tight mater- ial, and a wetting and spreading agent should be used in the sprays. In trials of 12 spray and dust combinations, sprays reduced infestation more than dusts. Combinations including derris were more satisfactory than those including nicotine, the best being 3 pounds of derris (U per- cent rotenone), with 1 pint of sulfated fatty alcohol containing a syn- thetic adhesive per 100 gallons 'of spray, which reduced the population by about 85 percent, as compared with that on an untreated plot. - ?6 - Hut's on, of Michigan (222), in 1°37 teucrted the order of effec- tiveness of insecticides for the control of the pea aohid to be re; fol- lows: Nicotine vaporizer, nicotine dust, sprays, and rotenone dusts. Popper, of New Jersey £222), reported tests in 1937 ■with derris ponder di wit> talc to a rotenone content of, -1 percent. When the wind veloc J bqinperatur' were favorable at th ■■ time of applica- tion, the - nicotine dust proved to b< more effective than did the derris-root-dust mixtures. The derris-^foot dust without a condition- ing agent proved ;o 'bo ..lore effective than the derris-root dust contain- ing a conditioning agent (i percent). This was also true in a series of small-plot experiments. No si lifiqant differences could be noted in the kill of aphid- between applications on dry and on wet foliage, and no residual effects of derris-root dust to the pen aphi .. The aphid population, however, was do very rapidly 1 y natural Pri llminary experiments were also cor.dj.etod with vaporized oil spr- applied frdm-an airplane. The oil, of course, contained an insecticide. The insecticides tested in the vaporised oil were nicotine, derri= ex- tract, pyre thrum extract, and mixtures of derris end pyrethrun extracts. The data from the experimental plots showed a kill of appro: ly 75 t with scne of the dil- insecticide cor.bi nations. Derris-root dust applied from an airplane proved totally unsatisfactory as a control for the pee aphid. Hugh &lasg6w, of Hew York ( 222 ) , reported that in the case, of the rotenone-bearing dusts the initial "till in 1937 was often surprisingly d, but the fact that this kill was not always so consistent or so uniformly high as where either, rotenone sprays or nicotine preparations were used was somewhat disturbing. Haude ( ihh ) i n 1930 recommended cube or derris dust (l percent rotenone) plus 0*5 to 1 percent wetter, at 35 to k-C pounds per acre, pref- erably at high temperature and humidity: also a spray,. 3 pounds of powder of k percent rotenone- content per 100 gallons, plus a wetter, at 125 to 200 gallons per acre at 2^0 to 600 pounds' pressure; also a derris extract in oil as a vapor spraj from airplanes. Jen 3 (l£S; in the h-E Club Ins ;t Manual issued February 1939 re- com iorris or cube for the control of the pea aphid. 'Jetties (20_5)_j of South Carolina, in 1939 w rote that recent exper- iments in the North end T .', T est show that derris is a promising material for the control of the garden pea aphid but has not been tested as yet in the South. Crosby, Chupp , and Leiby (5%) in February 193 r '-'rote that a dust containing 1 percent ef rotenone may be substituted for the nicotine- line dust with good results for the control of the pea aphid. It should be applied at the rate of ~}0 to 50 pounds .to the acre.. Rotenone map also be. used -as a spray. Use 3 to k pound? of material containing U. to 5 P er cee.t of rotenone per ICO gallons of water plus 3 to 10 ounces of one of the sulfated alcohols, or similar spreader. Walker and Anderson (298) in August 193 C! reported that vaporized u - 37 - nicotine applied while the plants were dry gave the most satisfactory control of the pea aphid under field conditions "by the pea growers in the Horfolk, Va. , area. Derri? and cube sprays in combination with suit- able wetting and spreading agents have given good control of the pea aphid in experimental tests but failed to give satisfactory results in some field trials by pea growers. Santex R, containing a derris extract, has given promising results as a spray, in comparison with sprays con- taining cube powder. In general, derris and cube have not given so good control of the pea aphid when used . s dusts as when used as sprays. Tests were made with cube powder U pounds or S pounds per 100 gallons plus SS-3, 1:600; cube-talc dust (rotenone 1 percent); cube-walnut- shell flour (rotenone 1 percent); also the same plus- 1 percent of Vatsol OS or 1 percent of Grassclli IN-1S1 P. Stantex-R (no T - r called Stantex R 50) is a mixture of 80 percent of Stantex Dispersing Oil and 20 percent of a derris extract containing 5 gm. of rotenone in 100 cc. of a camphor- sassafras-base oil. Stantex Dispersing Oil is a mineral oil containing a small percentage of oleic acid and a wetting agent. 3oth are made by Standard Chemical Products, Inc., Eoboken, 1". J. SS-^ (now called G-rasselli Spreader-Sticker) con- tains sodium oleyl sulfate as the spreader and a synthetic plastic as the sticker. G-rasselli Il'-lSl P contains sodium lauryl sulfate in a powdered form. Other wetting agents tested with cube were Areskap, Dry Aresket, Elgete (emulsified peanut oil), G-rasselli IN-U38 (sodium oleyl sulfate), Santomerse, Stantex Spreader Soap, and Ultrawet. A dust con- taining 0,75 percent of rotenone and 0.098 percent of pyrethrins gave "best results when applied late in the evening, and valorized nicotine gave best results when the plants were free from dew. Wilson and Dieter ( 311 ) , of Wisconsin, reported in 1939 that the results obtained against the pea aphid with rotenone-bearing materials. although variable because of widely different climatic conditions in 1 Q 37 and 193^. were reasonably satisfactory in both year^. Such materials were effective wfien sufficient moisture was present and the temperature sufficiently high (approximately 70° P.). Observations indicate that in general it is possible to obtain commercial control of pea aphids on pea vines with one properly timed treatment. In 193'-' field tests were run with all the commercial dusts sold in Wisconsin and, when the temperatures were high, satisfactory results were obtained from each dust after 2^ hours. Self-mixed dusts were also used. Derris (5 percent rotenone and lh percent total ether extractives), and cube were mixed with various diluents so that the final mixture contained 1 percent of rotenone, 1 percent of liquid wetting and spreading agent, and 2 percent of water by weight. These dusts were applied at ~$0 rounds aer acre and all were ef- fective in reducing the pea aphid population more than 90 percent on treated plots after 2h hours. Rotenone dusts are most effective when applied to peas wet with dew or rain and when the weather is fairly warm (above 70° P.). Heavy rain following as early as 5 or 6 hours after the dust is applied does not seriously injure the effectiveness of the treatment, provided the pee,s are moist when dusted. Under favorable conditions 20 pounds per acre of a dust containing 1 percent- of rotenone gives good results, but it is safer to use 25 to 30 pounds per acre. — Wisconsin Agricultural Experiment Station (320) in 1939. -, 33 - Ground derris or cube root has proved effective in killing aphids, and has the advantage of loi-; - cheaper to use than nicotine vapor.- . P.o te- nor, e insecticides may be applied in either ditst or spfray form with almq&t eaually good results, hut dusts are generally preferred because they make it unnecessary to haul large quantities of water. The best practice is to treat the near- when the first f lover bads appear. Tests made in l' ! 3 7 arid IJJiS indicate that roterione-be.&ring products are most effective if applied vrhor umiditj is high — that is, when there is a dew or shortly after a rain. The best time of the: day is in the morning, late afternoon, or evening, rather than midday. The fact that night applica- tions are especially effective is presumed to be largely because there is generally some dew on the plants at that time, but absence of wind at night may also prevent the dusts froE ceinp blown away. Another experimental fi\n . ro*i hone dusts are nor? effec- tive in killing aphids vrhen the temperature is. above 70° P. In l c early applications made in cool weather did cot reduce the number of aphids until alter 9 days; "cut as soon as 'temperatures became hither, good control resulted within 2- hours. One puzzling fact, which has not bt.en explained, is that rotenone seem? to give the vieas some protection wnen applied during cool weather, even though the aphids are not immedi- ate!:- 'rilled. For this reason it is not possible, without further re- search, to say definitely whether it is wise to wait until the tempera- ture is above 7C C before using rotenone dusts. The Wisconsin Agricultural Experiment Station ( ^l6 ) in 19^? report- en excellent control of the pea aphid with sprays of powdered derris root. Dusts were not consistently effective. Yields of peas, as record- ed at the factor-, showed increases ranging from 62 to 131 percent with the various tre; ts, as compared with untreated plots. The average increase was 36 percent. In these trials there mas a higher percentage of small-sized peas in the check plots than in the treated plots. Trials were mad( 0: the late-plant s with concentrations cf J pounds per IOC gallons in the fall of 1935* Excellent control cf aphids was a t :ain obtain proximately 9? percent of tji°. insects being killed ^oy a heavy application of derris spray. One application after the aphid in- festation had begun served to Protect tJ ac from' damage for nearly a th. trials with 3 - tration erris as low as 1/U to 1/2 pound per 100 gallons of water with spreaders and wettin - agents - , killed appr ; ' bely as largi a percent cf. aphids as did 3 poWls per 100 gallons^ About 200 gallons of sprs^y was reouired per ^cro. Derris con- tai . " - t'of rbtenono :iilad sloval' T over a. ocriod "of 7. ll or 5 dame, depending en weather .conditions. There was littl. or no repro- duction during the period in which a- hide were dying. Indications were that when derris sprays were used the plants remained uninfested -f or a longer period after treatment than *- r ith any of the other poisons tested. The same' station ; 'jlc ,- 319 ) in its annual report for 1077 stated that derris- tall a- dust containing 1 percent of rotenone and sprays c.ontai? ing from 0.005 to 0.015 percent 02 r t v.oac gave pood control of the aphid. Single treatments applied b fori June 15 resulted in large in- creases in yield. Of th'< treatmentc applied before June 20, five dust.in, tests produced en average increase in yield of IJ'S percent, whereas thre spraying tests resulted in an average" increase of 101 percent. Diphenyl ii n »i i i iMi»i r« u — m i i i . ii n i w i i w ii i ni f w - 39 - sodium sulfonate and sodium olcyl sulfate vrere used as wetting agents. For the control of^ the pea aphid, canners now have 'a choice of two effective insecticides — nicotine in a gas form and rotenone in either wet sprays or dusts. Nicotine as nor/ used gives, excellent commercial control under proper conditions/, and rotenone materials also are r;ood if carefully applied. Any insecticide containing at least 1 percent of rotenone will probably be effective, applied either as a spray or a dust, and all the 1 percent rotenone materials tested, as well as the nicotine-gas method, reduced pea aphid population by 90 to 95 percent • within a day or two in trials conducted by Wilson at Columbus in 1937. Field treatments in this and other areas in many instances gave equally good control where the insecticides were properly applied. The conditions under which rotenone dusts are used may have some bearing on the amount needed. About 30 pounds per acre of a dust con- taining 1 percent of rotenone is a safe amount under most circumstances. As little as 20 pounds was used with good results in trials in 1933, but it may be risky to try economizing to this extent, particularly if weather conditions are not such as to make the rotenone immediately effective. — Wisconsin Agricultural Experiment Station ( 3J?Q ) in May 1939. The Wisconsin Agricultural Experiment Station (322) in 1940 reported that 2-year trials have indicated that if a properly mixed dust containing 0.75 to 1 percent of rotenone is stored in a dry warehouse, it will usually be about as effective the second year as it is the first. In fact, one good commercial dust held over from the 1937 season gave excellent results in 1938 and also satisfactory results in 19 39. Three others mixed in 1938 proved satisfactory in 1959. Experiments in pea aphid control carried out on 57 l/4-acro plots on a farm near Waunakee, Dane county, in 1939 brought out especially favorable results with derris-dust mixtures. Although aphid infestations were very light at this location, derris-dust mixtures appeared to increase yields in several cf these tests. Average yield increases in three experiments were 612, 555, and 555 pounds per acre, respectively. Rotenone ousts cause relatively slight injury to ladybeetles, im- portant aphid predators. Only adult beetles were rafther consistently injured by rotenone dust, and even the adults often were able to lay large numbers of eggs after being dusted. Larvae were seldom. injured unless they had just molted at the time the dust ras applied. The eggs of lady beetles were uninjured, even when heavily coated with dust. Macro si phuia solanifolii (Ashm.), the potato aphid Kclndoo and Sievers ( 188) in 1924 reported that cube as a dust and as an infusion ras effective, but us^d r.s a cold-r.ater extract with soap it had practically no effect. The cold alcoholic extracts of cube and derris plus soap were effective, Kelsall et al, (169) in 1926 reported the results cf tests with derric against the potato aphid in the irisectary. The presence of moisture had a marked effect in increasim: the toxicit ,r of derris. - 40 - A dust containing 2,5 parts of derris and 97.5 parts of hydrated lime gave 100-percent control in 5 daj^s when the foliage was first dipped in water and the dust then blown on. Derris in spray form required 5 pounds per 100 imperial gallons of water to rroduce 100-percent mortal- ity, while nicotine sulfate (40 percent), \fl pint to 100 gallons, gave control. In all tests derris ■ nicotine. the same control. In all tests derris was much slower in action than x . . j. McDaniel ( 186 ) in 1928 wrote that the potato aphid was controlled by Derrisol. Derris dust failed to give satisfactory control in the field. — Walker and Anderson ( 298 ); also reported by Cory (277) in 1935. Manschke (191) in 1937 reported that 96.5 percent of red and green potato aphids on tomato were killed by a spray consisting of 2 pounds of derris powder (4 percent rotenone) per 100 gallons of water plus about 3/4 ounce of coconut-oil soap (40 percent dry soap) per gallon. The rotenone preparations Cvbor, Fiagron, and Kubatcx and derris were effective. — Massachusetts Agricultural Experiment Station ( 194 ) in 1937, Pepper (224) in 1937 reported on the control of pink and green aphids, M. solanifo lii, on tomatoes in New Jersey. Nicotine was more effective than derris or pyre thrum. The estimated results of pyrethrum, derris, and mixtures of pyrethrum-derris dust, as compared with 4 percent nicotine dust, are tabulated as follows: Treatme nt Estimated control ( Percent ) Pyrethrum- talc (25:75) 50 Derris dust (0,75 percent rotenone) 35 Pyrethrum 50 pounds, derris root (4 percent rotenone) 20 pounds, and talc 30 pounds 70 A commercial mixture of derris and pyrethrum (0 3 5 percent rotenone and 0.2 percent pyrethrins) 60 Four percent-nicotine dust 95 Approximately 30 to 35 pounds of the above mixtures was applied per acre. Oils impregnated with pyrethrum and derris extract were sprayed from an airplane. Poor kill (about 25 percent) was obtained from the application of regular kerosene 10 gallons, concentrate of pyrethrum plus derris 1 gallon, and highly refined petroleum distillate 10 gallons plus concentrate of pyrethrum-derris 1 gallon. There was little difference between the treated plots; and, since the percentage kill of aphids was so low and time was limited, actual counts were not made. The airplane sprayer did not break up the spray as fine as was expected. Poor dis- tribution of the fog or oil particles was, no doubt, a part of the cause of 000 r results. ■1 ■ i \ mmmmmmmmmmBmmmmmmmmmmmmmmmmmmmmfmm - 41 - After adjusting the airplane spraying equipment so as to produce a fine fog, 1 gallon of pyrethrum-derris concentrate to 30 gallons of oil reduced the aphid population 40.1 percent. A later court indicated a reduction of 71.4. percent. Nicotine (l gallon of 50 percent free nico- tine to 27 gallons of oil) reduced the population in the two counts 68.3 and 94.5 percent, respectively. Smith ( 244 ) in 1937 reported that derris powder (4 percent rotenone) at 2 pounds per 100 gallons of water plus l-l/4 pounds (dry "basis) coconut- oil soap or l/2 pound Dry Aresket 300 caused a reduction of 96.5 percent in the population of pink and green potato aphids on tomato plants. Counts were made at the end of 24 hours. Craufurd-Benson (57) in 1938 experimented with M. solanifolii collected in the field as a test insect for determining the value of liquid contact insecticides, especially derris preparations, but found the results to be completely unreliable. Gunderson (134) in 1938 recommended derris against potato aphids. Cube or derris dust is ineffective, — Eaude ( 144 ) in 1939. Macro si phum rosa e (L.), the rose aphid Mclndoo and Sievers ( 18 8 ) in 1924 repcrted that a cold alcoholic, and also a benzene extract of cube were effective when used with soap. TTeoton (derris extract in fish oil) 75 gm. plus twice its weight of soap in 40 imperial gallons killed 100 percent. — Institute of Physical and Chemical Research ( 162 ) in 1927. F'oliafume (a pyrethrum-derris spray with spreader) at 1:400 killed 94 percent in 48 hours. — Penick and Company (223) in 1936. A bed of about 40 rose plants infested with M. rosae was divided into two parts and sprayed with 0.25 and 0.5 pint of commercial acetone derris extract containing 5 percert of rocenore per 100 gallons, respec- tively, 0.2 percent of soap being used in each case. Complete control of this insect was obtained with the 0.5-pint concentration and about 80 to 90 percent with the 0.25-pint spray mixture. — Cdnsburg and Granett (124) in 1935. Siphoncpho ra Macros iphum rosae (L.) is killed by a proprietary dust containing 12 percent of cube of 6 percent rotenone content. — Etablissements Eotenia in a letter to P.i C. Roark in 1938. Macros iphum rudbeckiae (Fitch), the goldenglow aphid; or cone flower aphid Darley (6J2) in 1931 reported comparative testr with rotenone, nico- tine, and pyrethrum on aphids. Rotenone was used in two stock eclutions, one consisting of 0.2 gm. of rotenone, 5 cc. of benzol, and 95 cc. of Penetrcl; the other of 1 gm. of rotencne in 50 cc. of acetone. A few preliminary tests again:;t M. £j££t> ec 1 c i ae_ on goldenrcd gave the following results: Black" Leaf 40 at 1:1,000 (nicotine 1:2, 500 ) produced a ~ - 42 - mortality of 56 percent; Nicotrol at 1:200 (nicotine 1:10,000), 97.9 percent; Penethrum at 1:200 (pyrethrins 1:74,800), 80 percent; No. 519 at 1:200 (rotenone 1:100,000), 96.9 percent. The check mortality was 23.2 percent. Turner (2¥l) in 1952 reported that cube extract dissolved in mineral oil and emulsified with sodium oleate deteriorated during the 5 days following preparation. Applications made at a dilution of 1:250,000 of cube extract against M. rudbe c kiae killed from 42.7 to 91.6 percent. Cube extract in mineral oil emulsified with powdered skimmed milk did not decompose on 2 weeks' standing, a dilution of cube extract of 1:300,000 killing from 54.8 to 74.1 percent of the aphids. Macrosiphum soiidaginis (F.) Turner (271) in 1932 reported that cube extract in oil, emulsified with a sulfonate emulsifier, at a dilution of 1:40,000 killed 81.7 per- cent of fc. soiidaginis , whereas a solution of nicotine sulfate (40- percent nicotine")" at 1:300 killed only 41.2 percent. Macro siphuiTi spp . Mclndoo and Sievers (188) in 1924 reported numerous tests of cube and derris in the form of dusts and alcoholic and aqueous extracts agains unidentified aphids designated as Macrosiphum spp. "A" and "C." The alcoholic extracts were the most toxic. The smoke from burning derris and cube powders was effective against the species "C." My zu.s c era si (P.), the black cherry aphid The Michigan Agricultural Experiment Station ( 199 ) in 1925 reported that derris sprays had given encouraging but not conclusive results against the block cherry aphid. The Wisconsin Agricultural Experiment Station ( 513 ) in 1926 reported that the petal spray is probably the best for cherry aphid control, and Derrisol, imported from England, scorned to possess superior qualities; and in its annual report for 1927 (314) stated that both Dorrisol and nicotine sulfate wore effective at dilutions of 1:800 parts of water. They were about equally efficient, but Dorrisol was cheaper, more pleasant to apply, and gave better coverage, although it took from 24 to 43 hours after spraying for aphids to die. The same station ( 315 ) in 1929 reported that Dorrisol applied early in the season before the cherry leaves unfold gave commercial control of the cherry aphid; in 1938 ( 318 ) reported that the black cherry aphids in Door County were controlled by various insecticides, including seven products containing rotenone; and in 1940 (522) reported that the evidenc of the past season was that derris and bordeaux could be used together for control of" the black cherry aphid. Good control resulted when Dri- Spray, a proprietary derr:s powder, was used at 3-1/4 pounds to 100 gallons of half- strength bordeaux (made v/p of 1-1/2 pounds of copper sulfate and 2 pounds of lime in 50 gallons of water). Dri-Spray also - 4S - gave •" . ults when used ?.lone a J -. 3-1 f to 10! :i s water in this el?:berr.r.ent, but e canine re ial cherry grower failed I . entirely satisf story control ~f aphids r-hen he - ne treai merit during a cool spell, with temperatures ground 60° to 65° F. Thin indicated thai dor:-::- .- s t.c centre] cherry :-: -Kit's should be used during y/arn weather 1 ■ c ults, a: 5 bhe case ". uch insecticides ar for i ontrcl of j e aphids. ffyzus persicae (Suls. ), the --re." ; - ■ aphid, spinach aphid, or tobacco aphid ext : pli powdo] 1924 r-clndrc and Sievers ( 188 ) reported that derris used as a fund (bumec) was effective. DeOhg and JVhite (7G) in 1924 reported that a eommertial derris ex- tract diluted 1:500 gave a 50-percent control of the green pea.- . Ld, Diluted 1:300 a maximum control of 68 percent was obtained. Van der Meer Mohr (196) in 1S27 reported that K, per sicae is a serious pest of tobacco in Deli, -Sur.iatra. The seedbeds are infested from the adjacent forests, and the Tiling plants in tho field are eitl r infested in the same way or by the introduction of infested secdlii from tho bods, li the bods stre v ry badly infested the should bo destroyed or dipped in derris solution^, experiments having shown that this does not harp then. In the plantations a da atch should be kept for the first traces of infestation. Spraying with a solution of derris is advised. The application must be repeate< r 4 to 5 days. Deli Froefs'taticn of Medan, Sumatra (69) ir 1929 published information or. the use of tuba (derris") root extrac lir.st M, persicae on tobacCo, Fulmek in 1922 ■ introduce tuba root on a large sc, r combating +-};is insert, Even in excessive quantities it did no e tobac i - root extract is made as follov r s: The ieces 1 to 2 inches lone and mixed with sin times it; :- • sher or less tratcr is I I. root is cr I in 20 to 30 minutes by vertically running millstones, >roughlj sieved, and i residue prcssec by a hydraulic . : - - iquid passes throu Tiro s is rnixe< - first extract. The liquid is 1 ' : ith 0.5 percent of formalin and, when put t?ghtly : casks, : y p for seme months. This Ls- fectory for the Deli conditions because tho cxtraot is only during the planting season and y ithin a short time. This is ; xr the cheapest insecticide for the Deli planters. The manufacture is under continuous control of tie entomologists c r ' the experiment stati- . An aver ' 00 liters of the stock solution is sent ye to the tobacco planters. Derris is far superior to nicotine sulfate in killing E. pers icae. ' soap does not effect t Lai qualities. m\ - 44 - The proef station (70) in 1S31 reported that M. per si cae was unusually abundant on tobacco, and large amounts of derris extract were used to combat it. Neoton at 0,1 percent was more effective and cheaper than the 1:45 akar toeba (derris) of the proef station; however, it was necessary uo use a.' small proportion of soap to prevent the separa- tion of oil from the Neoton, which otherwise leads to unequal distribution of the spray. In 19 33 the same station (7l) reported comparative experi- ments made at two place.? with Neoton and akar toeba, to see whether these insecticides had any influence on the quality of tobacco to which they were applied. The Neoton was used at 0.1 percent, together with some soap; the akar toeba, at a dilution of 1:40 in a 0.1 percent soap solution. Neither treatment had any marked effect on quality. From the insecticidal standpoint, the akar toeba extract was not inferior and there is no reason for replacing it with iTooton. Derrothan as a dust was effective in laboratory tests out Derrothan emulsion burned the tobacco plants. During the 4 months January-April, inclusive, 1932 the akar toeba factory at Sikambing, Sumatra, distributed 708,000 liters of aqueous extract of derris Davidson (63) in 1930 killed 98.2 percent of these aphids in a greenhouse with rotenone suspended in water at a concentration of 1:100,000 and 94.3 percent at a concentration of 1:200,000. A dust containing 2 parts of rotenone and 98 parts of diatomaceous earth killed 76.6 percent. This aphid was i ..ised as a test insect by Davidson and Jones (65) in 1931 in studying the. loss of toxicity suffered by rotenone in certain solvents and in aqueous suspension. A freshly prepared suspension of rotenone made by adding an acetone solution of it to water at 1:50,000 killed more than 95 percent. The green peach aphid was used by Davidson as a test insect and referred to by Shepard ( 241 ) in 1931 (see Brev ic oryn e brassicae L., page 18 . Tattersf :'i eld (258) in 1932 discussed laboratory methods for evalu- ating insecticides. Results of tests with two samples of derris root against M. p ersi cae are stated as follows: The two samples had the seme rotenone content, and over a definite range of concentrations (up to 0.05 per- cent;, expressed in terms of root, the results for equivalent concentrations do not differ by more than the ' • . . experimental error, although sample F is always slightly less effective. The results are normal up to a certain concentration (0.05 percent), and then, above that strength, both samples are shown to be less effective than below it. In the case of root B, the results are scarcely significant, but in the case of root F definitely significant. Obviously two factors are working in opposite directions. In discussing how far the factor of time should be taken into account in judging toxic effects quantitatively, Tattersf ield wrote: 1 '' i ii mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm - 45 - If the rapidity i action had only boon taken into account in the past, & number of valuable insecticides' vrould never have come-to ligkfe. There is a startling difference betv/een the rapidity of effect of the pyrethrins on the one hand and rotenone on the other; for -.Thoroas the rapid narcosis produced by the pyrothrins nay vcar off at concentrations bclov: a certain level, the narcotic effect of rotenone dc opens" "in intensity v/ith time. Turner ( 271 ) in 1932 repcrted the results of work carried on during 1928-31, inclusive, tvith cube extract and vd.th rotononc obtainou from cube, Cube extract v.cs incorporated in a sulfonated Tiineral oil called "oil- soluble sul fonate" by dissolving the proper amount of cube extract in benzol, mixing this rath the oil-soluble sulfonate, and evaporating the benzol at lov, r temperature. This preparation at a dilution of 1:200,000 of total extract of cube killed 37.5 percent cf M. p cr ricae. Five months later this prepurath ve the sane percentage of kill, indicating no decomposition cf the rotcnone in that time, W. DuR, Thornc, American Vice Consul, at Medan, Sumatra, reported in 1933 that the Deli Experimental. Station buys derris not on a basis of rotcnone content but on a basis of other extract to combat M. pcrsic ac on tobacco. The concentrated aqueous extract i^ diluted 1:40 for use, Garman (117) in 1934 reported that a commercial rotenone preparation at 1:1,000 plus bead soap at 1:1,000 gave relatively poor results against the green peach aphid. Trappmann and ditsche ( 27_0_ ) in 1935 reported 100-percent mortality in 4 d-ays of (Phor odon (MyzoderTJ) Myzus .persicae when sprayed v/ith a suspension of rotenone Xo.l5-percent rotenone ) plus Turkey-red oil. The dosage ". r as r^-.eulated to give a deposit of 0.18 mg. of rotenone per 500 cm. Derris dust failed to give satisfactory control in the field.— TBalkor and Andersen (297); also reported by Cory ( 277 ) in 1935. Deshpande (77) in 1937 reported that usually tr/o species of aphids, Liyzus P^J^jcae and ( Siph o ooryne indobrassicae Das) F ho p-a 1 o s i phum psex^dobrassicae (Davis") are found attacking cabbage and that both of them go under the common name of cabbage aphid. In 1952 Derrisol at 1:800 killed 100 percent of the aphids. Derrisol is not no-; manufactured, hence is no longei available. Dust containing 0.75 percent rotenone may be used to control this insect on spinach, cabbage, and cauliflov;er on Long Island. Tt is advisable to make the application late in the afternoon or early in the evening -.Then do:; is expected. — Crosby, Chupp, and Leiby (_53) in 1939. Kau.de (144) in 1939 recommended cube or derris dust (0.75 percent rotenone) plus 0.5 to 1 percent of a -/.-otter, to be applied at 30 to 50 pounds per acre vath a canvas trailer v.hen the plants are dry. STATE. .^BOABQ - 46 - Pentalonia nigronervosa Coq. Ocfemia ( 215 ) in 1931 wrote on bunchy-top of abaca in the Philip- pines and its control. This disease is caused by a virus which is spread from plant to plant by the aphid P, nigroner vosa . For control the stools should be dug up, chopped in pieces,' and sprayed with nicotine or derris spray. The soil around the stools should also be sprayed. Derris spray is prepared from 1 kg. of derris roots and 10 liters of water: "Pound the roots of derris thoroughly and macerate them in water over night. Strain through cloth. For use take 1 part of the infusion and dilute it with 10 parts of water." Per iphyllus lyro pictus (Kess.), the Norway-maple aphid Hamilton and Cemmell (137) in 1934 reported that in nursery tests against the Norway-maple aphid derris dust (l percent rotenone) killed 40 percent. Pho ro do n humuli (Schr.), the hop aphid Winston ( 312 ) in 1926 reviewed information on Derrisol for the benefit of Florida citrus growers* Reference was made to its use against hop aphids in England. Derrisol should be diluted 1:800 for use against aphids. Derris or rotenone suspensions at concentrations of 1:5,000 or 1:6,250 were effective.— DeBussy et al. ( 52 ) in 1935. Hampp and Jehl (139) in 1938 reported that sprays of derris alone and with pyrethrum gave excellent results against hep aphids on hops in Germany, It was recommended that nicotine be used until blossom time, and derris or derris with pyre th run from then on. Warwick ( 3C0 ) in 1938 reported that in England derris products are used very effectively against the hop aphid. Pterochlo rus tropical is Van der Goot Neoton (derris extract in fish oil) 225 gm. plus an equal weight of soap, in 40 imperial gallons of water, killed 100 percent. --Institute of Physical and Chemical Research (162) in 1927. Phopal o s iphum prunifoliae (Fitch), the apple grain aphid Headlee ( 145 ) in 1026 reported that Derrisine diluted 1:100 in two tests permitted 52 and 32 percent of the eggs of ( Aphis avenae F. ) Rhopal os iphum prunifoliae to hatch as compared with an average of 58.8 percent in the checks, A block of 10 young Delicious apple trees was sprayed with a mixture consisting of 3 pounds of colloidal copper fungicide, 1 pound of derris (5 percent rotenone), commercial oil emulsion to give 3 percent actual oil, and 100 gallons of water. The sprays were applied during the - 47 - last days of April, v:hen most of the leaves vera about l/2 inch out. Subsequent observations disclosed that approximately 90 to 95 percent of the hatched aphJ.ds (Siphocoryno a venae) were deed on this block within 48 hours after spray app] i cation. — Ginsburg and Granett (124_) in 1935. [According to P. W. Mason, the aphids referred to in the two preceding paragraphs probably are R. prunif olia c. 1 Rhopalosiphum pseu dobras s?. c ae (Davis), the turnip aphid; false cabbage aphid, Indian mustard aphid, or turnip louse Hclndoo, Sievers and Abbott (18&.) in 1919 killed 100 percent of this species in laboratory tests with derris dust. Darley (62) in 1931 found that in tests in the field, rotenone at a concentration of 1:100,000 as a contact poison in spray form compared favorably in toxicity with nicotine at 1:10,000 and pyrethrins at 1:74,800. Penetrol at the same concentration ( 1:200 ) was used in each spray. Rotenone at 1:100,000 killed 98.5 percent of these aphids in 43 hours. Little (183) in 1931 reported that field experiments on this species with the powdered root of [Cracca] Tep hrosia virgi n! ana showed that the plant has considerable promise as a contact spray. At 1:400 in water a spray of the powdered root of T. virginiana killed 93 percent of the tur- nip aphids. Turner ( 271 ) in 1932 reported that rotenone dissolved in oil- soluble sulfonate and applied at the rate of 1 part in 40,000 gave excellent control of' (Aphis) Rhopalosiphu m pse udobrassi cae on radishes in greenhouses. At the rates of 1:50,000 and 1:60,000 the results were not so satisfactory. In November 1933 Alien (5) reported that at Eaton Rouge, La., rotenone, in addition to killing the turnip aphid, protected the turnip plants for several days from attack by chewing insects, Derris dust diluted with tobacco dust of "-grade to 0.5 percent rotenone content, and derris dust diluted with sulfur dust to 0.5 percent rotenone content, protected plants from leaf-eating species from G to 8 day- a. Foliafume (a pyre thrum-dor ris spray with spreads r) at 1:400 killed 88 percent.— Penick and Company ( 225 ) rn 1936.. Allen (6) in October 1S34 reported that a dust containing 1 percent of rotenone rave promising results for the control of the turnip aohid on turnips and mustard. Equa] parts of finely ground tola. ceo dust and 300- mesh dusting sulfur were used as a diluent. Ts.c author stated that the ^.erris-root-dus t mixture should be thoroughly applied in such a manner that a light coating of it reaches the undersides of the leaves. It may be applied to wet or dry plants preferably in late afternoon. Good results have been obtained by making applications immediately after rains. - 48 - The dust should be applied at the rate of 20 to 25 pounds per acre, based on 3-1/2- to 4-foot rows with two rows of plants to each field row. Ordi- narily treatments should be made at 7- to 10-day intervals for best results,! Under field conditions sprays have not been so satisfactory as dusts against the turnip aphid or: turnip and mustard. It is difficult to roach the lice on the undersides of the leaves, especially on large plants. If a spray is preferred, a nicotine sulfate-soap solution is recommended* The United States Department of Agriculture, Bureau of Entomology and Plant Quarantine ( 273 ) in its annual report for 1935 stated that experiments on the turnip aphid in Louisiana indicate that derris dust may satisfactorily proteotjthe turnip crop from damage. In its annual report for 1936 the Bureau/stated that in tests directed against the turnip aphid in Louisiana insecticides containing rotenone, with sulfur and talc as diluents, were in general more effective in producing a satisfactory market product that wore insecticides containing nicotine. In 1939 the Bur (285) reported that insecticides containing rotenone had proved effective. Fenton ( 101 ) in 1936 referred to the report of Allen (£) and to unpublished work by Roney of Texas, who reported very good results at Dickinson with a dust containing 10 pounds of powdered derris or cube (5 percent rotenone), 15 pounds of pyrethrun dust (0,5 percent pyrethrins), and 75 pounds of 300-mosh conditioned sulfur. The dust did not cause any burn of the turnips and when applied early in the morning or late in the afternoon, v/hen dew was present and very little wind, it controlled this inspect. It was effective at temperatures as low as 45° F, Harrison ( 141 ) in September 1936 reported the results of field tests with in secticides" against the turnip aphid on Purple-top Globe turnips and Florida broadleaf mustard, at the Baton Rouge, La,, laboratory, of the Bureau, of Entomology and Plant Quarantine. A dust mixture containing 1 percent of rotenone, with equal parts of tobacco dust and sulfur as diluents, was superior to derris sprays, and dust mixtures containing nicotine sulfate. The dust mixture containing rotenone not only gave satisfactory reduction in the aphid population immediately after treat- ment but continued to inhibit the increase of aphids for a period of at least 6 days. Derris sprays ranked second in effectiveness against the aphids. A nicotine sulfate-dust mixture containing 3 percent of nicotine was effective against the aphids for a short period after application but did not afford adequate protection for so long a period as did the derris dusts or sprays. The Texas Agricultural Experiment Station ( 265) in 19 36 reported that for the control of R, ps eud ob ra s s i ca e a sulfur dust containing 0,075 percent of pyrethrins and also 0,5 percent of rotenone gave results inferior to Nicotrol (a nicotine product) at a dilution of 1:300, applied by means of a fan-shaped nozzle, Deshpande (77) in 1937 reported that usually two species of aphids, Myzus per si cae andT*S ipho c oryne indobrassicae Das) Rho palosiphum pseudo - brassicae , are found attacking cabbage, in India and that both of them go under the common name of cabbage aphid. In 1932 Derrisol at 1:800 killed 100 percent of the aphids. Derrisol is net now manufactured, hence is no longer available. ■■■■■■■■■^■■■■■i m ^y - The Louisiana Agricultural Experiment Station (184) in 1037 recom- mended derris diluted with sulfur, tobacco dust, clay, or talc to e rote- none content cf 1 percent for the control of the turnip aphid* The Texas Agricultural Experiment Station ( 266 ) in 1937 reported that the standard spray formula (ificot^ne sulfate plus penetrol) was superior to the rctenone-pyreth rum-sulfur combination in dust Torn, and remained more effective for a week or 10 days after the applications were made, Harrison ( 142 ) of the Bator: Route, La., laboratory, reported in 1939 that tests with 20 different dust mixtures, involving the use of dilutions of 1,0 and 0.5 percent of rotenone with various diluents and conditioners^ resulted in no significant difference'.-: in yield between the treatments. This indicates that the present standard recommendation for tur hid control ( rotencne-dust mixture containing 1-porcent of rotenone with equal parts of tobacco dust and sulfur) is not appreciably improved by the addi- tion of any of the more common conditioning agents used in combati ' aphids. Conditioning agents tested were: One or 2 percent of peanut oil, 4 percent of soybean flour, and 1 percent each of peanut butter, cottonseed oil, pine oil, oleic acid, sulfonated caster oil, sodium oleyl sulfate, and an alkyl ate d naph thai ene- s ul £ ona te . Haude ( 144 ) in 1939 recommended oube or derris dust (0. 75-percent rotenone) pli:s 0.5- to 1-percent of a wetter, applied at 30 to 50 ] per acre with a canvas trailer when the .Xante are dry, Rhopalos inhum subterraneum Mason Rhopal o s i phum sp, [probably R, s ubterrane um, ] (See reports of tests made by the South Caroline- Agricultural Experiment Station (249) and Rainwater (228) under Anuraphis maidi- rad ic i s Forbes, pp . H-5.) Toxoptera aurantij (Fonsc,), the black citrus aphid Tests ware made by Worsloy (323) in 1934 with Derris, Tephrosia , and Lonch o c arpus a citrus ap : ids at the East African Agricultural Research Station. Dried ground material was shaken in absolute alc< (9 cc, alcohol for each gm. of material) for 24 hours, filtered, and brought uo to 10 cc. volume per gn. of material by washing the with alcohol. This is called a 10-percent extract of the plant material. The method of assessing the effect • spray: bo take 10 aphids for each trial ami to examine them 24 hours after spraying. One-half percent of soap or 1 percent of saponin was added as a spreader 'he spray was applied for \ seconds from a distance oP 18 inches. Tests were mads with the root of Derris elliptica ; the flowers, seeds*, leav , .ds, stems, and roots of Tephrosia vogeliij the leaves, seeds, nd roots of —' toxic ari a; the leave:-, seeds", and pods ol T. nyikensis ; th seeds, and roots of T, C andida ; th leaves ai i seeds of T, tocfciflora ; and the leaves and roots of 2 sp< .>f Lone ho carpus " nd B, Extracts of Dorr is j] 1 ipt lea roots and e of t, vogelii bhe most toxic, killing 100 percent of the aphids. - 50 - Van der Scheer ( 259 ) in 1935 reported that rotenone-benzer.e emulsioi (l gm. rotenone, 20 cc, benzene, and 30 cc, visiter containing 0.1 to 0,15 Igepon T) at a concentration of 1:5,000 gave a 100-percent kill of the bla< citrus aphid on tea foliage, Worsley (324) in 1936 reported that Mundulea suberosa Benth, bark (0.9 percent rotenone) from Moa district, Tanganyika Territory, East Africi ■was even more toxic than derris root (5,4 percent rotenone) to this specie Concentrations, necessary to. give 100-percent kill of Toxopt cra aurantii were 0,06 percent for. nicotine, Q.125 percent for Mundulea bark, and 0,"l5 percent for derris, Trifidaph is phascoli (Pass,) See report of tests made by the South Carolina Agricultural Experi- ment Station ( 249 ) and Rainwater (228) under Anur a phis maidi - radicis Forbes, p. U. Derris applied to the seedbed before planting, and around the plants hastened the germination of cotton by 24 hours, but did not control 3 species of root aphids of v.hich T, phased i causes the most severe damage. United States Department "of . Agricultu"ro7*~5uroau of Entomology and Plant Quarantine (285) in 1939. Aphiidac (unidentified species) Aphids on apple Kopp ( 176 ) in 1924 reported that a spray consisting of 1 pound of derris powder plus 1 kg, of soap in 800 liters of water gave excellent results against apple aphids. The Michigan Agricultural Experiment Station ( 199 ) in 1925 reported that derris sprays had given encouraging but not conclusive results against various aphids on apple. Derris spray gives a good measure of control of aphids on apple trees in England. — Kearns, Marsh, and Pearce ( 168 ) in 1932, These insects were killed by derris dust (1 percent rotenone). — Do Bus ay et al . (_32) in 19 35. Aphids on beans Plant lice on lima beans, along with the Mexican bean beetle and mildew or pod mold, arc controlled by a rotenone preparation added to the bordeaux spray. — Suffolk County, N. Y,, Farm Bureau (254) in 1933, Aphids on birch Derris, l-l/2 pounds per 100 imperial gallons of water, with the addition of soap, was used against aphids on a cut-leaf birch but they did not appear to be affected during the first 12 hours. Two days later the tree was found to be completely free of aphids. — Kelsall et al. (168) in 1926. -. 51 - Aphids on cabbage Fhite (304) in 1935 and again ( 306 ) in 1936 stated that tests have indicated that derris dusts may aid in the control of certain aphids that infest cabbage and related crops, DeBussy et al. (31) in 1936 stated that aphids can be readily con- trolled by spraying with a suspension of derris having a rotenone concen- tration of 1:10,000 or by spraying with a pure-rotenore suspension containing rotenone at a concentration of 1:5,000, During 1935 deBussy and associates used derris dusting powders (0,5 percent rotenone plus 1,2 percent ether extract) against several varieties of leaf lice, including gray aphids on cabbage seed. There was no kill of these insects. From this it is concluded that in only a few cases can satisfactory results against aphids be expected when derris powder is used as a dust. Spraying v/ith derris extracts 1.-; to be favored. Derris dusts effective against cabbage worms do not give satisfactory control of plant lice,— Colorado Agricultural Experiment Station (50) in 1936. The New South Wales Entomological Branch -(209) in 1936 reported that, where derris dust is applied throughout the season at 7- to 10-day intervals for the control of Plutella maculipennis (Curt.), it will also check green aphid infestation but does not control the slaty-gray aphids. Merino and Otanes ( 197 ) in 1938 recommended a derris-soap spray for the control of aphids on cabbage. Either dried or fresh derris roots may be used, Aphids on cauliflower Infestations of aphids in the cauliflower seedbed during July were effectively controlled by dusts containing 0.5 and 0,33 percent of rotenone. The applications were made late in the evening under calm conditions, in anticipation of high relative humidity during the night. — New York Agricultural Experiment Station (213) in 1937, Aphids on Ceylon ironwood Miller ( 201 ) in 1935 tried aphids or Ceylon ironwood ( Me su a ferrea L. ) as test insects in determining the irs-ecticidal value of various species of derris, but they proved too susceptible and difficult to handle; 100- percent mortality was obtained each time, not only with the insecticide but also with the control fluid. Aphids on cherry Earfoot (12) in 1935 stated that the cherry and, pear growers of the Bay district of California used several tons of cube dust for the control of aphids and ether insects. - 5-2 - Aphids on chestnut trees Black plant lice on chestnut trees fell off In a few rainutes when sprayed with a commercial derris product [probably Meoton] . — Anonymous (l, in 1927. Aphids on chrysanthemum Compton (51) in' 1930 recommended Derrisol for the control of aphids on chrysanthemums. Aphids on chrysanthemum were controlled by a rotenone spray of 1:5,000 plus 0,1 percent of Agral I.--Wageringen Plantenziektenkundigen Dienst (_293) in 1934. Aphids on citrus Symes ( 255 ) in 1924 reported that two proprietary derris extracts gave highly satisfactory results against che black citrus aphid in Rhodesia Winston ( 513 ) in 1926 reviewed information on Derrisol for the benefit of Florida citrus growers. Derrisol should be diluted 1:800 for use against aphids. Should a grower be spraying with lime and sulfur solution- for rust mites, oil emulsion for scale, bordeaux mixture for fungus diseases, or lead arsenate for chewing insects, and any aphids be present, an addition of Derrisol 1:800 will pay handsomely, enabling this pest to be controlled with the one spraying; or if aphids are present and no other application is to be made, Derrisol mixed with water without soap will be the cheapest efficient liquid aphicide that can be applied. Ehoads and Debusk (230) in 1931 recommended derris preparations at the rate of 1 pint to 100 gallons of water for spring applications for the control of aphids on citrus in Florida. These should be applied at the time of first flush of growth. By employing some of the more effi- cient spreaders (certain oxidized oil derivatives, oleates, or pine-oil soaps) the quantity of nicotine sulfate or derris compounds required for 100 gallons of spray mixture may be cut down to 1/4 pint at a 50rpercei saving in cost. For the spray to be applied late in winter, 1 table- spoonful of derris compound to 2 gallons of water is recommended. Basinger and Boyce (13) in 1956 reported that cryolite and barium fluosilicate may be combined with derris preparations for citrus aphid control. Organic compounds used alone were ineffective. The California Fruit Growers' Exchange, Bureau o£ Pest Control (35), in August 1936 reported that Ortho Derris and Tox-X with from l/2 to 2/3 percent of light medium oil have given good results against aphids. The Leffingwell Company in 1937, in a letter to R. C. Roark, stated that Tox-X (2,5 percent rotenone plus a spreader) plus oil has given promising results against aphids on citrus in California. - 53 - Boyce and Prendergast (19_) in 1938 v.rotc that the oil rotcnone mixtures are relatively expensive when considered for the control of the red spider alonej however, when considered for the combined control of aphids, the red spider, and "off-hatch" black scale during the spring, they arc very practical. The California Fruit Growers' Exchange, Bureau of Pest Control (38, 39, 40), in 1938 recommended oil-rotenone combinations for combating the citrus aphid, A 'suitable spray is made from 0,5 to 0,75 gallon of light medium oil, 1 to 4 pounds (depending on brand), of rotcnone powder, and water, to make 100 gallons. This formula may best be used where the red spider and black scale are present along with the aphids. One of the rotenone oil sprays such as Botano-R, Tox-X, or Rotox with 0,5 percent light medium oil will control both aphids and red spiders on citrus. The rotenone-oil combinations used effectively against the red spider on oranges in the coastal Valencia area also cares for any aphids present, Aphids en corn Miller (202) in 1935 tried aphids on corn as test insects in deter- mining the insec~£Tcidal value of various species of Derr is, but they proved too susceptible and difficult to handle; 100-percent mortality was obtained each time, not only with the insecticide but also with the control fluid. Aphids on currant The currant aphid was net controlled by a dust of equal parts of derris and hydrated lime. — Kelsall et al. ( 170) in 1926, Aphids on dwarf spruce The 1 Wageningen Plant enziektenkundigen Dienst ( 29 3 ) in 1933 reported that a suspension of rotcnone in water (l: 5,000 ) made by adding an acetone solution of rotenone to water and also derris pov/der in water 1:50 (equiva- lent to rotenone at 1:2,500) plus 1 percent of soap gave satisfactory con- trol of' leaf aphids on dwarf spruce in Holland, Aphids on eggplant The Japan Seed and Plant Company, Ltd,, of Tokyo, Japan, in advertising Derri-Homi (a proprietary derris product), stated [n.d.] that the Agricultural Experiment Station of Saitama Prefecture, Japan, found that this product at about 1:320 killed 100 percent of aphids on eggplant. Aphids on flowers and fruit The Handelsmuseum of the Koloniaal Instituut of Amsterdam (8) in 1930 reported derris to be an exceptional material for contrcl of aphids on flowers and fruit in the greenhouse. Fryer ( 108 ) in 1S26 referred to the use of Derrisol in England for the control of aphids on fruit. - 54 - Aphids on goldenrod A red aphid on goldenrod was not controlled by a dust of equal parts of derris and hydrated lime. — Kelsall et al . ( 169 ) in 1926. Aphids on head lettuce The aphids that could be reached were killed by spraying vdth rote- none at l:5,000i It is impossible to reach all the aphids conveniently, therefore the results remained incomplete. --DeBussy, et al, (32) in 1935. Aphids on hops Fryer (108) in 1926 referred to the use of Derrisol in England for the control of aphids on hops. Aphids on Japanese maple The Wageningen Plantenziektenkundigen Dienst (292) in 1933 reported that a suspension of rotenone in water (1:5, 000) made by adding an aceton solution of rotenone to water, and also derris powder in water, 1:50 (equivalent to rotenone at 1:2,500), plus 1 percent of soap gave satis- factory control of leaf aphids on Japanese maple in Holland. Aphids on lotus The Japan Seed and Plant Company, Ltd., reported [n,d.] that at about 1:190 Derri-Homi killed 100 percent of aphids on lotus at Saitama Prefecture, According to the manufacturers, this product contains derris extractives and spreading and sticking agents, Aphids on nasturtium Fulrner ( 113 ) in 1930 wrote that the nasturtium aphid can be effec- tively controlled by spraying with derris pov/der, 5 pounds per 100 imperial gallons. Aphids on ornamental cherry The Wageningen Plantenziektenkundigen Dienst (292) in 1933 reported that a suspension of rotenone in water (1:5,000) made by adding an acetone solution of rotenone to water and also derris powder in v/ater, 1:50 (equivalent to rotenone 1:2, 500) plus 1 percent of soap gave satisfactory control of leaf aphids on ornamental cherry in Holland. Aphids on ox-eye daisy The Wageningen Plantenziektenkundigen Dienst (_292) in 1933 report* that- derris powder (2 percent rotenone) when added to 50 parts of 1 per- cent soap solution (l part rotenone to 2,500 parts v/ater) and also a sus- pension of rotenone in rater (1:5,000) made by adding an acetone solutio: of rotenone to water gave satisfactory control or leaf aphids en ox-eye daisy in Holland, **■*'• ' " u**»™™*~»»****mmmmmmmmmmmmmmmmmmmmm - 55 - Aphids on peanut Miller ( 201 ) in 1935 tried aphids or. peanut as test insects in deter- mining the insecticidal value of various species of derris but they proved too susceptible and difficult to handle: 100-percent mortality was obtained each time, not only with the insecticide but also with the control fluid, Aphids on pear Neoton, 110 gm. plus 450 gm. of soap in 40 imperial gallons of water, killed 100 percent. — Institute Physical and Chemical Research ( 162) in 1927. Aphids on pear were controlled by a rotenone spray 1:5,000 plus 0.1 percent Agral I ,— Wareningen Plantenziektenkundigen Dienst ( 295 ) in 193' Aphids on plum At Saitama Prefecture, Japan, Derri-Homi at about 1:476 killed 100 percent of aphids on plum trees, according to the Japan Seed and Plant Company, Ltd, [n.d.]. Neoton, 1 pound in 60 imperial gallons of water, killed 100 percent; 1 pound in 100 gallons killed 99,1 percent. — Institute Physical and Chemical Research ( 162 ) in 1927. Aphids on plum were controlled by a rotenone spray 1:5,000 plus 0,1 percent Agral I.--Wageningen Plantenziektenkundigen Dienst (295) in 1934. Aphids on raspberries Kearns and fc-arsh ( 182 ) in 1937 reported that derris spray (0.004 percent rotenone) is preferable to derris dust (0.18 percent rotenone), as it provides a control for aphids on raspberry as well as for the raspberry beetle, Aphids on rose The Saitama Prefecture, Japan, Experiment Station reported that at about 1:238 Derri-Homi killed 100 percent of aphids on rose tree. — Japan Seed and Plant Company, Ltd., in advertising literature [n.d.], Rosebush aphids were quickly killed by a spray of a commercial derris product [probably Neoton] .--Anonymous (l) in 1927, Cory (54) in 1P38 issued a schedule of treatments for the control of rose pests. Rotenone dust is used for the control of aphids but is not so effective as nicotine dust. Hamilton ( 156 ) in 1938 reported cube find derris powders (4 percent rotenone and 16 to 18 percent total extractives) applied as a spray at the rate of 4 pounds per 100 gallons, with the addition of 4 pounds of rosin- residue emulsion, gave a good kill of aphids on roses. 1 - 56 - Dusts containing 0.75 percent rotenonc are satisfactory. — Haude (145) in. 1559. (1 C Aphids (it ses Van d^r Scheer (25 1 .;) in 1935 reported that rotenone-benzene emulsion gm. rotenone, 20 cc, benzene, and 55 cc, water containing 0.1 to 0.15 gm. ] gepon T) at leaf aphid. concentration of 1:5,000 gave good control of the sesame Aphids or soybean Miller ( 201 ) in 1935 tried aphids on soybean as test insects in determining bhe insecticidal vali 3 : f various species of Derris but tbey proved too susceptible a ! ;, to handle; mortality was 100 percent in each test, not only wit] the insecticide but also with the control fluid, Aphids en spirea 00 1:1,2 The Ohio Agricultural /.vperiment Station (216) in 1922 reported that roent of trie aphids en Spirea vanhouttei were killed by Derrisene at Aphids on strawberry Brooks*, Watson, anr? Mowry (30) in 1932 reported that derris prepara- tions may be used iristead of nicotTne sulfate for spraying aphids attacking the abowe-grourid parts of strawberry plants. * Aphids on tobacco Westerman (503) in 1901 recomm ended a solution of derris root as a spray 1'oy^ use against lice on tobacco on the east coast of Sumatra. Eollrung (145) in 1523 wrote that in Sumatra the following prepara- tion had given good results against leaf lice on tobacco: 1-1/2 kg. of fresh tuba root mashed in 20 liters of water and diluted with an equal volume of water for use. Fulnek (109, 110) in 1924, in discussing insecticides for use against tobacco pests in Sumatra, listed akar tuba (derris) as a contact insecticide. The addition of 0.3 to 0.5 percent of soar to solutions of derris is advised, and akar tuba is re,coi:miended for leaf lice on tobacco at the rate of 1 kg, in 100 liters of water to which 0.5 kg. of soap is added. Fulmek ( 113 ) - n 1925 gave directions for spraying against leaf lice with derris. The formula is 1 kg, of akar tuba (derris), 100 liters of water, and 300 gm, of soap. In 1927 Fulmek ( 112 ) reported the use of a 1-percent water extract of the roots of Derris elliptica for the control of plant lice on tobacco in Sumatra, Bourcart (17) in his book, "Insecticides, Fungicides, and Weed KillersJ stated that a spray containing 1 pound of derris, 10 imperial rallcns of water, and 5 ounces of soft soap is effective against aphids infesting tobacco in \*wwm#ws?sw iiii i i gia i t?Ti i »iiwww aaewKw^iwii - 57 - Sumatra. The derris roots, which may be dry or fresh, are cut into small pieces, placed in a little water, and then pounded into a paste, which is diluted with a gallon of water and left standing overnight in a wooden vat. The dregs are then pressed, and all the fluid is strained through a cotton cloth. The resultant concentrate is a milk-white solution, which keeps for a few days only. It is diluted with 9 parts of water for spray- ing. About 16 imperial gallons of solution are needed for 1,000 tobacco plants that have been from 25 to 30 days in the field. Twice this quantity is needed for full-grown plants. If derris roots are to be stored they must be kept dry. The Deli Proef station at liedan (67) in 1926 reported that akar toeba extract gave excellent control of aphids on tobacco. Some difficulty was experienced in obtaining a uniform extract, so this was' prepared with the machinery of the Delische Kleiindustrie. Formalin was added, to a concen- tration of 2.5 percent as a preservative. The proefstation (68) in 1927 reported that derris extracts (suspensions of the milky sap in water), supplied by the proefstation to tobacco growers, retain their toxicity for at least 1 year when kept in well-closed barrels. Decomposition occurs in open vessels and in those not hermetically closed. The suspension becomes gray or nearly black, develops the odor of hydrogen sulfide, and loses effectiveness. Contact with iron is stated to be undesirable. Redecker (229) in 1926 called attention to the large-scale use of aqueous derris extract in Sumatra for destroying aphids on tobacco. W, A, Foote, American Consul at Medan, Sumatra, in May 1929 sub- mitted a report to the United States Bureau of Foreign and Domestic Commerce on the use of derris in fighting tobacco plant pests. Against tobacco lice an aqueous extract of fresh derris root at 1:40 is more effective but slower than 3 percent of nicotine with soap. In 19 31 Foote (#L06) reported that a liquid contact insecticide prepared from derris was used against the tobacco aphid in Sumatra. Hand pumps were more effective than power sprayers in applying it. Braddock (20), American Vice Consul at Medan, Sumatra, in 1930 reported that derris is used on practically all the tobacco estates to combat aphids. The insecticide is prepared by the Deli Proefstation and supplied to the planters at cost. The station supplied the following quantities (expressed in liters) of derris extract to the tobacco growersj In 1926, 35,000j in 1927, 77,000; in 1928, 56,000; and in 1929, 65,000. The Wageningen Plantenziektenkundigen Dienst (292) in 1933 reported that derris extract had long been used for the control of leaf aphids in the Deli tobacco fields, and for some time had been a' constituent of proprietary extracts. Hendren (l_46_), American Trade Commissioner at Ratavia, Java, in 1931 reported that tuba (derris) extract is an excellent remedy for aphids on tobacco in Java, ■ - 58 - Aphids on tomato Aphid s on tomato plants were killed "by Cubor 75 dust (0.75 percent! rotenone),. and derris-gypsum dust (0,4 percent rotenone). — Herman and Hockey (147) in 1936. Rotenone dust is ineffective. — Haude ( 144 ) in 1939. Aphids on viburnum - / Aphids on viburnum were controlled by a rotenone spray 1:5,000 plus 0,1 percent of Agral I, — Wageningen Plantenziektenkundigen Dienst . ( 295 ) in 19 34. Aphids on violets Compton (51) in 1930 recommended Derrisol (l ounce to 4 or 5 gallor of water) for the control of aphids on violets and pansies. Aphids on white pine Hamilton ( 156 ) in 1938 reported that cube and derris powders (4 per] cent rotenone and from 16 to 18 percent total extractives) applied as a spray at the rate of 4 pounds per 100 gallons, with the addition of 4 pounds rosin-residue emulsion, gave a poor kill of anhids on white pine. Aphids in general Epp (95) in 1851 described the use .of derris as an insecticide in Banka (an island lying east of Sumatra). It was used for destroying tree lice. For this purpose the root was cut into pieces, soaked for some days in water, and sprinkled on the plants. w YJahl and Mul'ler- (294) in 1915 reported that the derris preparations Contraohin and Katakilla. are effective against plant lice at concentration of 1:250 and 1:200, respectively. The Annual Report of the Bureau of Entomology, United States Department of Agriculture for 1919 ( 275 ) stated that if derris can be obtained in sufficient quantities it xvill prove an important addition to our list of substances that kill soft-bodied insects, such as plant lice. The California Agricultural Experiment Station (33) in its annual report for 1922-23 stated that Derrisir.e (an extract of derris) was un- satisfactory as an aphicid'e. Dilutions of 1:300 were 68 percent efficient, whereas 1:500 gave a control of but 50,5 percent. An undiluted powdered derris root when .dusted on aphids was 100 percent effective in 8 hours. — DeOng and Tvhite (75) in 1924. The Federated Malay States Department of Agriculture (99) in 1924 recommended for sucking insects a spray made by adding 8 to 10 pounds of derris root and 4 pounds of soap to 100 imperial gallons of water. - 59 - Mclndoo and Sievers (188) in 1924 reported numerous tests of cube and derris in the fonr of dust s , and alcoholic and aqueous extracts, agains' unidentified aphids designated as Aphis spy). A, B, C, D, and E, In general these preparations were highly effective. Carlos (47) in 1926 reported that. derris as a contact or external poison, rath or "without the use of soap as a spreading agent, had been found effective against aphids in as low a dilution as 1 pound of root to 400 gallons of water, which represents a proportion of 0.025 percent, Aphids are some of the chief insect pests Which can be easily exter- minated by the application of insecticides containing derris or its products. One interesting property of derris as a killing agent is that the effect lasts for a considerable time. Leaves sprayed with a solution containing derris preparations will remain poisonous to insects for many days , William Cooper and Nephews, in the February 1926 issue of Florida Entomologist, advertised Derriscl, stating that it was a new aphid spray having no odor, being nonpoisonous and pleasant to use, did not require soap, could be mixed. with other sprays, and could be used with hard or soft water. The Deli Proefstaticn (68) in Medan, Sumatra, in 1927 reported that derris was satisfactory for the control of aphids, but Derrisol was found ineffective at 1:400, although it was claimed to be effective at 1:800. TJeotcn at 110 gm. plus 22.0 gm. of soap per 40 imperial gallons killed 100 percent of arrowhead aphids, and at half this concentration nearly all were killed. Neoton at l/2 pound per 40 imperial gallons of xvater killed 100 percent of unidentified aphids,— Institute Physical and Chemical Research (162) in 1927, KcDaniel (186) in 1928 recommended Derrisol as a contact spray for use against aphids and Metcalf and Flint ( 193 ) in 1920 summarized current information on derris, which they recommended for aphid control. Dammerman (61) in his book, "The Agricultural Zoology of the Malay Archipelago," published in Amsterdam in 1929, mentions derris as having come much into use as an insecticide. t To prepare the insecticide the roots of derris are pow- dered, and the product _is now on the market. It is not of such a high value as was first expected, but being cheap in our region it may be found a useful substance. For making a spray, fresh roots are macerated with water, as a rule a 1- percent solution of derris is found most satisfactory; a stock solution is made by placing 1 kg. of comminuted roots in 10 liters of water in a vrooden vessel, the solution standing over for 1 night; the stock solution after being strained through a cloth is; diluted 1:10. But as it is impossible to ascertain the exact content of the toxic sub- stance in a solution this insecticide is comewhat unreliable. - 60 - In Deli, Sumatra, a 1-percent solution, to "which is added 0.5 percent of soap, is used successfully against aphids. The liquid, however, keeps its efficiency for a few days only. The Dqtch proprietary insecticide known as Phyto- philine probably also contains derris, but it is far too expensive. According to an anonymous writer (2) in 1930, a spray containing as little as 0,025 percent of derris extract (obtained by extracting with water) is effective as a contact poison for aphids. Corbett (52), entomologist for the Federated Malay States Depart- ment of Agriculture, in 1930 reported that plants regularly sprayed with tuba at the rate of 1 pound to 10 imperial gallons of water will be kept comparatively free from aphids and similar insects. Peyer ( 228 ) in 1C30 recommended a spray made by adding 1 kg. of derris powder and l/2 kg, of soap in 100 kg. water for control of sucking insects. Schmitt ( 240 ) in 1930 in a discussion of derris stated that different kinds of leaf lice were controlled by derris dust or by derris- extract spray. The "Wageningen Plantenziektenkundigen Dienst ( 291 ) in 1931 reported that derris was unsatisfactory for the control of leaf lice on various plants in the field at Aalsmeer. Betrem (14) in 1931 coir> pared imported ground derris with nicotine as a control for black aphids in the entomological laboratory in Wageningen, Holland. No details were given, but the results were very disappointing. The author pointed out that this was probably due to poor quality of sample, and discussed the need of judging derris by its rote- none content, and not by its total ether extract, because there is no correlation between them, according to figures from Spoon. He also dis- cussed briefly the methods of using derris, the advisability of adding soap, and the manner in which it kills insects, Derris is entirely harmless to plants, whereas nicotine sometimes burns. Betrem believes that derris is the coming insecticide for greenhouse use. Katakilla should be applied as a spray at 0,5 to 0,75 percent con- centration a'gainst aphids. — Deutscher Pflanzenschutzdienst (78) in 1931, Andries (10) in 1932 recommended Derrisol and Katakilla for use against "green fly" (aphids). Goff and Tissot (129) in 1932 reported that extracts of derris are scarcely more effective than nicotine against aphids, and as there is little difference in cost their use has not become general. Like the pyre thrum sprays, the derris extracts are somewhat more effective than nicotine against some of the larger, more resistant insects. Certain activators, such as sodium and ootassium cleates, pine tar soaps, and a sulfonated oil product, increase the effectiveness of the derris sprays slightly. ~ - 61 - Ginsburg (121) in 1933 stated that -when only aphids are present, 1/2 pint of an acetone extract of derris (5 percent rotenone, 20 percent total extractives) to 100 gallons of water, containing about 0.2 5 percent of coconut oil soap, is sufficient, Gnadinger ( 128 ), in the first edition -of his hook, "Pyrethrum Flowers," concluded that the on] r it c ] a Ivantage in adding rotenone to pyrethrum sprays is to increase bhe toxicity to aphids, Unpublished work tr Ginsburg is cited which indicates that rotenone is rore toxic than the pyre thr ins tc aphids, Hamilton (136) in 1933 stated that derris and cube powders have a distirct repellent effect anc si [Yrrni -tin:- effect against certain insects, such as plant lice. Spoon (250) in 1. '0, r oorted sprays of derri: powder with half its weight of soap and red: tone ensions made by pouring an acetone solu- tion into '.rater plus 0.1 percent Agral or 0,05 percent Lethalate as a spreader (rotenone concentrations 1:2, 50C and 1:5,000, respectively) to bo effective agaj ] : aphids in holla: d. Benkert and Company, Inc., oh her: York, N, Y. , in March 1934 stated in advertising literature that derris dust is effective against plant lice. An alcoholic extract of derris plus soap was effective against plant lice. --Bock (15) in 1934, The lubber Service Laboratories, Inc. (235), in 1934 reported that a spray containing 7 ports of derris resin, 35 parts of dry Aresco, and 60 parts of pine Til (or oleic acid) is effective against aphids at 1:800. The Alabama Polytechnic Institute (3) in 1955 reported that derris dust alone is not very effective in controlling plant lice hut -alien mixed with sulfur is of soae value in repelling these insects. DeLussy et al. (32) in 1935 reported that aphids can readily be controlled by spraying with a suspension of dsr.ris having a rotenone concentration of 1:10,000 or by spraying .ltd a pure- rotenone suspension containing rotenone at a concentration of 1:5,000. During 1955 dehussy associates usnd derris dusting powders against ;reon and black Ids with the following results: Host plant - 62 - Str ength of dus t in g, mixture Rote none : Ether extract Green aphid s: Rose ------ Do Do - - Plum Black aph ids; Garden beans - - Cherry - - - - - Poppy - Dahlia - - - Percent 1.50 1.00 .50 .50 1.00 .50 .50 Percent 0.6 1.2 2.4 1.2 1.2 2.4 1.2 1.2 Mortality Percent 59 74 89 70 67 5 2 The authors concluded that satisfactory results "by dusting with. derris powder against aphids can be expected in only a few cases. Spray- ing with derris extracts is to be favored. Van der Laan (177) in 1935 reported dihjrdro rotenone to be less toxic than rotenone to red and groen aphids. Miles and Miles ( 200 ) in 1935 discussed insect pests of glasshouse crops. They stated that aphids can be destroyed with 1 pound of derris powder per 100 imperial gallons of water, and about 6 gallons per 50 square yards of crop should be applied as a drench. The New Jersey Agricultural Experiment Station ( 206 ) in 1935 reported that derris and cube are practically equal in their toxicity to aphids, provided they contain about the same amounts of rotenone and total extractives. The Rubber Service Laboratories Company, Inc. (238) (a subsidiary of Monsanto Chemical Company), in 1935 recommended a mixture of 7 parts of derris resin, 33 parts of dry Areskap, and 60 parts of either pine oil or oleic acid at 1:800 for aphids. Van der Scheer (239) in 1935 reported that rotenone-benzene omulsi (1 gm. rotenone, 20 cc. benzene, and 30 cc. avater containing 0,1 to 0,15 gm. Igopon T) at a concentration of 1:5,000 gave good control of the gre aphid. The Deli Experiment Station, as reported by the Koloniaal Institui of Amsterdam. (1_74, 175) in 1936, I ound undiluted ground T ephrosia toxica ] root to have slight effect on leaf aphids, but derris was much more effective. 1936. Aphids in general are sensitive to derris. — Van der Laan (178) in Van der Vecht (287) in 1936 wrote that for the control of Aphidids [=Aphiidae] spraying with rotenone suspensions containing 0.005 to 0,02 percent of rotenone can be recomm ended, /.doing a spreader improves the effectiveness of the spray. - OO - The American Association of Economic Entomologists , Eastern Branch (7), in 1937 published ''Sntona, " a directory of insect-pest, control. Infor- mation on the chemistry, stability, and insectioidal uses of derris and cube is given and the principal njjanflffacturers of derris and cube products are listed. Plant sprays containing 1 pereent of rotencne and 4 percent of total acetone extractives of derris root will give good kill of plant lice at a dilution of 1 part to 80C parts of -water. This gives a dilution of rotencne equal to 0.00125 percent. * Bourne and Boyd (18) in 1937 recommended rotenon r s for com- bating "^lant lice in the home garden. Dibble (79) in l r .38 stated that nicotine sulfate is better b] an derris or pyre thrum for killing most plant lice. Hamilton (136) in l r '36 reported tests of cube and derris powders (4 percent rotencne and 18 to 18 percent total extractives) applied as a spray at the rate of 4 pounds per 100 gallons, with the addition cf 4 pounds of rosin-residue emulsion, "colly aphids (various spool )s of Homoptera, Aphiidae) on beech, elm, larch, and white pine tr- s w re not satisfactorily .control .led. Aphids can be controlled by sprays of derris powder suspended in water containing even loss than 0.02 percent of rotencne. — Van dor Vccht ( 289 ) in 1938, Zaaijcr (325) in 1939 referred to Fund u lea suberosa (rotonone 5.4 percent) as an excellent insecticide for the control of aphids. Dibble, of the Dhited States Department of Agriculture's Extension Service, in a "Bug Flash" in 1940 reported that rotcnonc (dcrris-cube) dusts arc often satisfactory, although aphids still respond best to nico- tine sulfate plus hot soapy viator. Cercopidae A phrop hora permuta ta Uhl., strawberry spittle bu Edwards (93) in 1936 recommended powdered derris or cv.be diluted to 0,5 percent of rotencne with diat.omaceous earth for the control of spittle bugs on strawberries in Oregon. An application should be made 18 days after the first nymphs appear, and 2 weeks later a second application should be made. About 150 pounds of dust n er acre should be usi Hyd rated- lime dust containing 2 percent of nicotine is effective but pyre- thrum is ineffective, 1 from 30- to 50-percent control. ! " Lr. 3 3: recommence ust containing 0.5 percent of rotcnonc. Clastoptera sp,, cranberry spittl ct A spray of 5 pounds of derris powder (4 percent rotenone) and 4 unds of fish-oil soap in 100 ga ] r, led at the rate of 3 gal] -on June 16, v a poor kill of the nymphs in their. - 64 - spittle; but 6 pounds of derris powder (4 percent rotenone) and 4 pounds of fish-oil soap in 100 gallons of water, applied at the rate of 400 galloM per acre, gave a fair kill; and 8 pounds of derris powder (4 percent rotenone) and 3 pounds of fish-oil soap in 100 gallons of water, used' at the rate of 400 gallons per acre on June 16, killed nearly all the nymphs,* This last spray seems to compete on oven terms with nicotine sulfate in both cost arid effectiveness as a treatment for this pe3t, and, as the costfi of derris' is' in time likely to fall much more than that of nicotine sul- fate, it should, perhaps, be preferred. — Massachusetts Agricultural Experiment Station {19_4) in 19 37, Phila e nus leucopht ha lmus (L.)(P. s puma r iu s (L.)), spittle bug Adults are only slightly sensitive to derris, — DeBussy et al . (30) in 1936. Edwards (93) in 1936 recommended a d\i.st containing 0,5 percent of rotenone (see also under Aphrophors. permutata Uhl . ) . This insect on carnations and strawberries is repelled by a pro- prietary dust containing 12 percent of cube of 6 percent rotenone content, according to a letter from Etablissements Hotenia to R. C. Foark in 1938. Philaenus leuc ophthalmus fall en i (V.D.) (P, spumarius fallen! V,D,) Philaenus leucophthalmus gibbus (Fall,) (P, spumarius. gibbus Fall.) Philaenus 1 euc ophthalnu s ustulatus (Fall,) (P, spum arius ustul atus Fall.) Hanson and Webster (140) in 1938 recommended a dust containing 0,5 percent of rotenone for the control of these spittle bugs on strawberries] Cercopidae (unidentified species) Massachusetts State College in its 1937 insect and disease control chart showed the use of 8 pounds of derris powder (4 percent rotenone) plus 2 pounds of soap iri 100 gallons water on Juno 13 to 15, for spittle insects on cranberries. Smith (245) in 1940 reported that rotenone dust was being used in Skamania County, Wash., for the control of spittle bugs, Che mi da e Chermes abietis L., eastern spruce gall aphid Gambrell (115) in 1931 reported that ( Adelges. ) Che rmes abietis is an important enemy of Norway spruce in New York nurseries, Miscibls oils and oil emulsions have given good control but have injured some trees* i Lime sulfur 1:40 gave 100-pcrccnt control; nicotine 1:800 with 5 pounds of laundry soap per 100 gallons or with Penetrol 1:200 gave 99.9-pcrcent control; 5 pounds of laundry soap per 100 gallons alone gave 96. l6-pcrcont control, Derrisol 1:800 gave 54,72-percent control. In no case was there any foliage injury. m mm _. - 65 - Rotenohe in oil emulsified in water with powdered mil:-: (rotenone 1:25.000; oil 1,0 percent) killed IOC percent of ' les of this species; hut oho check oil did likewise a — Turner (271 ) ir 1S32. C he p aes code;/ i Gi 1 1 . 3 SO, The eggs of (Adelges) Chermes on pir.e were not killed by sprayj with a suspension of rotenone in water (1:20,000). — Davidson ( 85 , in 19c . Derris (32) in 19:5 5, Hot affected "by derris e — Van dor Lean (178) in 1935. Kelsall et al„ (169) in 192-3 reported that derris dust 'had appar- ently no effect on Chermes. Cicadeilidae Erpcasca fabae (Harr. ), potato leafhopper, been leafhoppor Do Long (72) in 1925 reported that a commercial derris pro.duct diluted 1:250 proved un satisfactory against the potato leafhopper. icert and Company,, Ir.c,, New "fori", N. 7., in March 1934 stated in advertising literature that derris dust is effective against bean lea: hoppers. Turner ( 275 ) in 1935 reported that three applications of derris dust containing 0,4 .percent of rotenone reduced the injury caused by the bean le of hopper. The Massachusetts Agricultural Experiment Station (19?) in ]936 reported that Cubor and JTubatox (C.5 percent rotenone ;, each plus bor- deaux 5-5-50, increased the yield of potatoes, because of leafhopper control. Manschke ( 191 ; in 1937 reported that 54- percent of 1 afhoppers on beans wore killed by •■ ■ isting of 2 pounds of derris dor (4 percent rotenone) per 100 gallons of r.ater plus about 2 pounds (dry basis) of coconut-oil soap, Rotenone pr tions --ere effective, ace to the Massachusetts Agricultural Experiment Station ( l9 i in 1937, Derris dusts have given satisfactory results.— Few Jers ; ;ri- cultural Experiment Station ( 207 ) in 1937, F, W, Poos, in quarterly reports to the Division of Cereal and Forage Insect Investigations, oi the tlureau ;f Intomology ana Plant Qv -, states that ir 1036 and 1 5 39 he tested rotenc ~i ill w dust for the control of the potato 1 ocr. This dr.st applied three - 66 - times to peanut vines increased the yield of peanuts 44.4 percent and was superior to bordeaux and pyrethrum- sulfur dusts. On alfalfa the tests wore not conclusive because of dry weather, but the rotenone-sul "ur dust was inferior to the pyrethrum- sulfur dust. The treated alfalfa was greener fan the untreated. Sleesman (243) nve the following data on the relative populations of leafhopper nymphs en potatoes receiving various spray ana dust treat- ments at hcGuffey, Chic, in 1935. The numbers given are average! replications. 1 lve Treatment Leaf hopp er ny mphs lumber Sulfur-lime 90:10 6 Sulfur-derris (0,024 percent ro ten one) 13 Sulfur-pyre rhrum (0,05 percent pyrethrin) 8 Sulfur-pyre thrum ( 0.0125 percent pyrethrin) 11 Sulfur-pyre thrum (0.00625 percent pyrethrin) 10 Bordeaux 4-6-50 6 Bordeaux 8-4-50 8 Bordeaux 12-4-50 10 Copper-lime dust 20;80 20 Un sprayed 81 Smith (244) in 1937 reported that derris powder (4 percent rotenone at 2 pounds per 100 gallons of water -lus about 2 pounds (dry-basis of coconut-oil soap reduced the leafhopper population on beans 94 percent 72 hours after spraying. Turner ( 274 ) in 1937 reported that a derris-clay dust (rotenone 0.6 percent) y/a£ not effective against the potato leafhopper on dahlias. Eoward (149) reported that in 1932 sulfur and sulfur-pyrethrum dust gavp the best control oi the potato leafhopper on beans in Ohio. Derris sprays were comparatively ineffective, ".hen used with peanut oil or pine oil the effectiveness of the derris sprays was increas'ed, hut peanut oil caused a yellowing of the bean ? eaves and subsequent defoliation and, although pine oil caused less ir.i\iry to bhe bean foliage, it appeared to be too injurious to he recommended for cenersl use. Sla.pta.son (242) in 1958 recorded some comparisons of dusts for potato leafhopper control en Long Island, when the insects were unusually abundant, The dusts were applied at the rate of 3 5 pounds per acre per applicat ion with an 8-rov Messenger duster mounted on the draw bar of an Oliver tractor and operated by a power take-off. The Cobbler variety* -wa^j dusted five times and the Green fountains six times during the growing season. All the materials used were prepared in a Bean self-mining duster just prior to each application. Two preparations contained rotenor (l) A mixture of 15 pounds of root of 5 percent rotenone contert vdth 85 pounds oi Bancroft clay, and (2; a mixture cf 10 pounds of pyrethrum, 15 pounds of rotenone-bearin. 5 root, 37.5 pounds of Bancroft clay, and 37.5 pounds' of dusting sulfur. On cobblers, rotenone was rather ineffective he plants receiving this treatment in the control ef leafhopj ers, an about 4 or 5 days after the check vine showed 100-percent hopperfcurn. at which time they also - 67 - The plants dusted with the 3-Way mixture consisting of pyrethrum, rotenone, and sulfur outyielded all the others, both in total yields and with highly significant differences as regards first-size potatoes. These materials used separately as dusts gave increases in yield over the undusted ones, but these were large enough to be significant for first- size potatoes only with pyrethrum and rotenone. Perhaps the simplest hypothesis to account for the success of the 3-Way mixture is that the effect of these different materials is independent and additive; there- fore, pyrethrum when used alone increased the yield of first-size potatoes, as compered with the undusted, by 37,63 bushels in the acre, the rotenone by 26.25 bushels, and the sulfur by 14 bushels, making a total of 77.88 bushels. This is not significantly different from the 93,38 bushels on each acre-increase produced by the combination mixture of these three materials. The arrangement of the experiment did not "permit an evalua- tion of the insecticidal effects of the Bancroft Clay. On Green Mountain potatoes both copper-line and the 3-Yiay dust markedly reduced the numbers of leaf hoppers. The untreated vires showed 100-percent injury by hoppers, while plants dusted with copper-lime showed only 25-percent injur;''; however, the plants treated with the 5-'..t.y mixture s- " only 10 percent injury on the same date. The final results show the highest yields from plants dusted with the 3-Y.ay mixture, where leaf/hoppers were best held in check. At the peak of leafhopper infestation there were 58 hoppers per plant on the plants treated with copper-lime, whereas the 3-Way mixture had reduced the.' infestation to 18 on each plant. As no late blight occurred in these plots, the higher yield obtained from the 5 -Way mixture compared with the copper-lime dust may have been due to the control of some insects ether than leafhoppers, although no appreciable numbers of other species were apparent, or to the stimulative action of pyrethrum. In 1936 on this same field a reduction in yield of 60 bushels on each acre resulted from the use of bordeaux mixture. The results of Skaptason ( 242 ) are referred to in Brimstone Brevities ( 521 ); and Eaude (144) in 193? recommended the 3-Way mixture for the control of the potato Leaf- hopper. Howard (150, 151) of the Columbus, Ohio, laboratory of the Bureau, reported in February and March 1939 that in comparing the efficiency of several dust mixtures and sprays against Empoasca fabae on beans during the course of experiments in Ohio in 1S38, it was shown conclusively that dusts of undiluted sulfur or a dust mixture made up at the rate of 90 pounds of sulfur and 10 pounds of pyrethrum containing 0,9 percent of total pyrethrins gave best results in controlling this pest. Sprays containing basic copper arsenate, basic copper sulfate, sulfur nitride, and derris (0,015 percent rotenone) were each ineffective. The addi- tion ci peanut butter [not peanut cil] to derris-dust mixtures increased their effectiveness. These mixtures were not sc efficient as undiluted sulfur or the sulfur-pyre thrum-dust mixture. Pine oil also 5 -ed the effectiveness of derris spray but appeared ' bean foliage to be recommended for pen era 1 use. - 68 - Empoasca mal i gn a (Walsh), apple 1 erf hopper Metcalf and Flint ( 198 ) in 1938 summarized current information on derris. Derris sprays are effective in killing the ;/oung nymphs of apple leafhoppers. The Idaho Agricultural 'Experiment Station (159) in its annual report for 1°32 stated that E* mal i gna is an important pest of the apple in southwestern Idaho, Among the materials tested and found satisfac- tory was Cubor (pyrethrum and rotenone). Erythroneura pal lidi Irons (Edw. ), glasshouse leafhopper Wilson ( 510 ) in 1938 reported that eradication of the glasshouse leafhopper from heavily infested greenhouses is difficult. It is not controlled by repeated fumigation with nicotine or with hydrocyanic acid gas at concentrations suitable for houses of mixed plants, and both adults and nymphs are very resistant to sprays, The best control is obtained by ducting rath nicotine, but the dust renders the foliage unsightly for some time. Sprays containing derris, pyrethrum extract, or eucalyptus oil are much less effective. Erythr oneu ra comes auct., net Say, grape leafhoppers Ever (97) in 1927 reported that Derrisol at the rate of 1 pint per 100 gallons killed 100 percent of the nymphs of the grape leafhopper, ( Typhi ocyba ) Erythroneura comes. Combined with bordeaux mixture 8-8-100, it killed 98 percent of the nymphs . Foliage caged 5 days after spraying with Derrisol, 1 pint to 100 gallons, indicated approximate control of 98 percent, and the same combined rath an 8-8-100 bordeaux gave a control of 96. percent. As an ovicide Derrisol was not so effective as pyrethrum- s o ap emu 1 s i o n , Runner, at the 1930 Codling Eoth Conference of the United States Department of Agricu.lture (276), reported a commercial derris extract at 1:800 to be effective against grape leafhopper nymphs but not against the eggs, A suspension of rotenone in raiter at 1:100,000 killed 100 percent. H Davidson (Qz) in 19 30. Used as a test insect ''oy Davidson and Jones (65) in 1931 in study- ing the loss of toxicity suffered by rotenone in certain solvents and in aqueous suspension. In the field a suspension of rotenone in water 1:100,000 killed 94,2 percent of grape leafhopper nymphs. Currie (59) in 1934 reported that in the Fresno, Calif., area a. rctencne-sulfur oust v.as compered, with a nicotine dust against the grape leafhopper. One pound of rotenone [derris] vjas mixed rath 8, 10, or 12 pounds of sulfur. The dusts -./ere applied at the rate of 20 poinds rer acre rath a hand duster during very ~ indy v:eather. At first the nicotine mixture showed the quickest and best results, but later there - 69 - was little difference in any of the test olots. Cn another ranch one application of 25 pounds per acre of a derris-dust mixture gave 99- percent control of hoppers, Hamilton and Gemmell ( 157 ) in 1934 compared the effectiveness of derris, pyre thrum, and hellebore pov.'ders against different insects. Dusts containing derris root po-.'der (air-floated, 4 percent rotenone), pyrethrum powder (1.16 percent pyrethrins), mixtures of these tiro, and hellebore ponder (0,8 percent active principle) were tested. Inert clay t.us used as a diluent. In field tests against the grape leaf- hopper, derris ponder, pyre thrum powder, and mixtures of the two gave satisfactory control uhen dusted either by hand or by machine. Appli- cations v.ith the power duster, at the rate of 100 pounds per acre, showed that dusts containing derris ponder equivalent to 0,5 percent of rotenone were nearly as effective as these containing 1,0 percent of rotenone. Hellebore was ineffective against the grape leafhopper. Heavy applica- tions of a dust containing 1,5 percent of nicotine knocked dov.n the grape leafhoppers but did not kill them, and all stages recovered in 1 to 2 hours , The Idaho Agricultural Experiment Station ( 160 ) in 1936 reported that cube-kaolin dust (0,2 percent rotenone) was effective against this insect. One thorough dusting of Virginia Creeper killed most of the nymphs and adults of the grape leafhopper and a second dusting 10 days later produced complete control. Two dustings 10 days apart controlled this insect on grapes. Foliafume (a pyrethrum-derris spray v.ith spreader) at 1:400 killed 95 percent in 48 hours. — Penick and Company ( 223 ) in 1936, Stearns, Haden, and T.illiams ( 252 ) in 1S36 reported that. Cubor (a rotenone and pyre thrum liquid spray) at 1:400 or 1:800 gave "adequate control of Erythro neura sp, in vineyards in Delaware, The Idaho Agricultural Experiment Station ( 161 ) in 1937 reported that a kill of 94,31 percent of the grape leafhopper was obtained v.ith one spray containing 0.49 percent of nicotine sulfate and 0,63 percent of summer oil. Better and more lasting results were obtained with this combination than vith derris or cube ponder in either dust or liquid fori or vith pyrethrum spray, Derris as a spray was more effective than as a dust. Parks and Pierstcrff (219) in 1938 recommended a 0,75 percent rotenone dust for the control of leafhoppers on grapes, Euptc ryx flavo scuta van, nigra Osb. KcBride ( 1S5 ) in 1926 reported tests vith insecticides against a leafhopper, Eupt-nryx flavo scut a var, nigra Csb,, attacking the leather fern ( P olys tichum capense J, Sm. ) in Florida, Five percent extract of derris, 1:800 plus soap, 2 pounds to 50 gallons, gave satisfactory con- trol. At the end of 5 hours 93,2 percent were dead and the following day 95 percent were dead. Spraying v.ith nicotine sulfato 1:800 plus seep, 2 pounds to 50 gallons, pins 5 percent extract of derris 1:800 - 70 - gave 100 percent control. Reinf estation occurred from, eggs deposited before the application of the spray. Richardson ( 251 ) , in a review of insecticidal research, referred to kcBride r s results. Sutettix tenellus (3ak. ), beet leafhopper Chamberlin (49) in 10 33 reported that preliminary tests at Twin Falls, Idaho, showed derris to be approximately as effective as pyrethrum when used in oil against the beet leafhopper. Douglass, TJakeland, and Gillett ( 83) in 1939 reported on field experiments for control of E_. tenellus in Idaho. In 1937 tests were made with derris (3 percent rot en one) at 4 pounds per 100 gallons plus 12.8 ounces Aresket, applied 4 times at dosages ranging from 110 to 150 gallons per acre. The insect population was decreased only after the fourth application. It was concluded that, of the materials tested, pyrethrum was the only insecticide found to be specific against the beet leafhopper. Iddocerus sp., mango hoppers Bhatta and Narayanan (15) in 1937 reported that at concentrations of 0.0S6 percent, suspensions in water of the uowdered roots of Derris eliiptica (harvested after 2 years 1 grovrbh) resulted in 80-percent mortality of Idiocerus sp. in the field. Tephrosia candida and Mundul ea se ricea v/ere ineffective at low concentrations against this pest. Sus- pensions of derris in later soon lost their toxicity. Water suspensions of Der ris eli iptica roots ( rotenone 7 percent and ether extractives 22 percent) killed mango hoppers at a concentration of 0.066 nercent. Alcoholic extracts and the powdered root as a dust —ere also effective .--Mysore, India, Department of Agriculture ( 205 ) in 1938. i Macrosteles diyisus (Uhl.j, six-spotted leafhopper The New York Agricultural Experiment Station at Cornell University (213) in 1937 reported that dusts containing sulfur, pyrethrum, and rote- none reduced the amount of lettuce yellows in experimental plots, through the control of lcafhoppers which spread the disease. Pepper and Haenseler ( 225 ) in April 1939 reported on the control of the six-spotted leafhopper, a vector of lettuce yellows. In 1936 rotenone-pyre thrum- sulfur dust and derris-talc-sulfur dust, (rotenone 0.75 percent) significantly reduced the leaf hopper-nymph population. Derris marc plus sulfur ;.as ineffective. In 1937 derris plus sulfur, derris plus p3'rethrum plus sulfur, and pyrethrum plus sulfur dusts gave best control of leafhopper. In 1938 tests were made with derris plus sulfur plus talc (rotenone 0.75 percent); derris plus sulfur plus talc plus Stemtox D (rotenone 0.50 percent and pyrethrins 0.0125 percent); and also with pyrethrum plus sulfur. The authors conclude that both rotenone and pyrethrum dusts give good control of the leafhopper. - 71 - Typhi ocyba froggatti Bak., a canary fly Evans (96) in 1938 reported that in Tasmania infestations of the canary fly on har.tho rn hedges may be reduced with derris dusts, one application being made early in November and a second one, if warranted, at the end of January. Typhi ocyba pomaria KcAtee, the white apple leaf hopper The Idaho Agricultural Experiment Station ( 1 59 ) in its annual report for 1932 stated that T. pomaria is an important, pest of the apple in southwestern Idaho, Among the materials tested and found to be satis- factory was Cubor (pyrethrum and rotenone). Cube extract in oil emulsi- fied i:: -water with powdered milk (cube 1:25,000; oil 0.5 percent) killed 82 percent of the first-brood nymphs. — Turner ( 271 ) in 1932. A dust containing 25 parts of derris (3.95 percent rotenone) and 75 parts of gypsum r.as ineffective in field tests. — Kelsall and Stultz (170) in 1937. The Massachusetts Agricultural Experiment Station ( 195 ) in 1938 reported the results of tests made at IValtham to control the white apple leafhopper. In laboratory experiments with pyrethrum and cube dust all leafhoppers were killed in 24 hours. Experiments at constant temperatures showed -a slight but not consistent increase in effectiveness at 80° F., but not at 60° or 70°. Typhi oc yba rosae (L.), the rose leafhopper McDaniel ( 186 ) in 1928 wrote that among the other better- known con- tact sprays are Derrisol and some of the pyre thrum extracts. With these, as with nicotine, each insect must be hit in order to be killed, (Empoa) T. rosae is one of the insects controlled by these contact sprays. Cicadellidae (unidentified species) Hamilton ( 135 ) in 1933 reported that derris and cube powders have a distinct repellent effect and some fumigating effect against leafhoppers. The Kentucky Agricultural Experiment Station ( 171 ) in 1934 reported that in studies with leafhoppers spray combinations containing rotenone, pyrethrum, and pine oil were more toxic than nicotine. Nico- tine caused nausea among the laborers in two instances, but the combina- tions did not. Derris was tested against leafhoppers but the infestation was too light to permit conclusions to be drawn. — Howard et al. (154) in 1935. Garman ( lis ) in 1936 reported that leafhoppers, although present in other parts of an apple orchard, ^;ere absent from the derris-sprayed olot. - 72 - The Florida Agricultural Experiment Station ( 105 ) in 1937 reported that sulfur dusts containing pyrethrum gave an immediate kill of jassids far superior to that obtained with sulfur dusts containing rotenone. However, a week after the applications wore made there ras little differ- ence between the pyre thrum- and rotenone-dusted plots, though the advantage was in favor of the pyrethrum. Cicadidae Magicicada sept endecim (L.), the periodical cicada Cory and Knight (_56_) in 1937 reported that Fed Arrow at a dilution of 1:400 killed 100 percent of all periodical cicadas hit. Spraying at night is preferable, as cicadas fly too actively during the day to permit of success then. Potenone [derris?] alone (4 pounds) and with Penetrol (l/2 gallon) per 100 gallons of water gave 25-percent kill. Coccidae Aonidi ella aurantii (Mask.), the California red scale R.H. Smith (24-6) in 1929 made tests against the California red scale on lemon trees with nicotine and extracts of pyrethrum, derris, three species of Tephrosia, and two species of Lonch o carpus , in a highly refined kerosene. l'6~^~omb~i.na t i on showed any p r a ctTca 1 va 1 v 1 , e . Smith (247) in 1932 described attempts to increase the effective- ness of highly refined spray oils by incorporating toxic substances (called "toxicants'') in them. Laboratory tests were made with kerosene and mineral-seal types of oil on (Chrysomphalus) Aonidiella aurantii, and orchard tests were made in which light-medium and medium spray oils •■ere used. Among the toxicants tested in a highly refined kerosene (viscosity 30 seconds, 98 percent unsulfona table, and applied as a mechan- j ical mixture in water without emulsifier) were nicotine, pyrethrins, rotenone, and various extracts of pyrethrum, Der ris elliptica, three species of Tephrcsia, Lcnchccarpus sp., and haiari. Butyl phthalate increased the solubility of rotcn one in the oils. Smith concluded that the attempts to iucrease the effectiveness of spray oils by the use of toxicants, in the experiments with the California red scale, were unsuccessful , Tox-X or Ortho Derris plus a reduced dosage of oil is decidedly loss effective than the regular oil sprays against the red scale. — Cali&ornia Fruit Growers' Exchange (34) in November 1935. In the August 1936 issue of their Pest Control Circular (35)" :"k ■■; so-called nonoil sprays, the California Fruit Growers' Exchange stated that Ortho Derris and Tox^X arc composed of a powdered insecticide containing derris added to a low dosage of light medium oil, usually l/2 to 2/5 percent. At the lower dosages of oil, these derris combinations have had little effect against the red scale. They cost several cents a tree more than oil sprays, "where used with light-medium oil at strengths as high as 1-1/2 percent, the cost approximates that - 73 - of fumigation, However, in orchards where the red scale is a p rob 1 err., in the light of present knowledge it would appear that these sprays, even with the higher dosages of oil, should not be substituted for the regular oil spray and fumigation program. The Leffjngwell Company in 1937, in a letter to R. C. Roark, stated that when Tox-a is used with oil it is fairly effective against the citrus red scale, and is superior to oil alone. The California Fruit Growers' Exchange, Bureau of Pest Control (43) in November 1938 reported on the use cf rotenone-oil products for the con- trol of the red scale on citrus. The extent of red scale kill has been directly related to the amound of oil used, without regard to the addition of botanical powder. On the whole, the minimizing effects of these lower dosages of oil on water rot of ?!avcl oranges has not been particu- larly pronounced. Furthermore, r.hen more than 1 percent of oil was used with rotenone, the cost over regular-dosage oils was increased. LaDue ( 179 ) in 1938 reported that during the winter of 1936-37 tests were made on a number of organic solvents from the standpoint of (1) the solubility of the derris resinate in the solvent: (2) the solu- bility of solvent in the spray oil; (3) the solubility or suspensibility of the derris resinate-solvent irixture in the spray oil; (4) the solu- bility of the solvent in water; and (5) the toxicity of the mixture to certain scale insects. The main groups of the solvents tested were (l) alcohols, (2) alcohol-ethers, (3) ethers, (4) glycols, (5) aldehydes, (6) ketones, (7) esters, (c) aliphatic amines, (9) chlorinated products of the saturated hydrocarbons, (10) phenols, (ll) benzene and benzene derivatives, and (12) the essential oils, Cnly a few compounds in each- group were tested. The higher ketones appearee to give the best results from the standpoint of solubility of the derris resinate, stability cf the resulting mixture, and added toxicity to the spray oil. Other com- pounds such as 2,2 f -dichlorethyl ether, sassafras oil, and the higher acetates appeared to be good solvents for derris resinate, and experi- mental data seem to indicate an added toxicity to the spray oil. A. aurant ii was used as the test insect. Derris resinate is not very soluble in highly refined petroleum oil such as is used in the spraying of citrus. Thus, when an appreciable amount of the derris resirate-solvent mixture is added to the oil, a sus- pension of resins and rotenone is formed. In the early part of 1937 laboratory experiments were made using methyl isobutyl ketone, methyl-n- amyl ketone, and 2,2 , -dichlorethyl ether as intermediary solvents for the derris resinate and tank-mix spray oil. Lemons infested with the California red scale were vised for the experiments, Derris resinate dissolved in raethyl-n-amyl ketone appeared to give the best kill of the three solvents, Sbeling has shown that methyl -n-amyl ketone incorporated in spray oil increases the toxicity of the oil to the red scale. Further laboratory and field work by Ebeling during the svffiiner and fall of 1937 also substantiates the above findings with regard to the toxicity of derris resinate to the red scale. 1 The United States Department Of Agriculture, Bureau of Entomology and Plant Quarantine (235) in its 12 08 .annual' report stated that prelimir Work had he-en done in California looking toward 'the development of the use] of added toxic-ante, including rotenone, with oils for the control of the California red scale Dutyl phthalate x.as found' to he a satisfactory sol* vent for petroleum oils end certain organic toxicants. Preliminary tests wore carried on with various petroleum ana vegetable oils in combination with nicotine and with rot en one. The California Fruit Growers' Exchange, Bureau of Pest Control (46) in November 1939 reported that-oil-rotenone sprays at 3/4 to 1 percent of light medium oil -..ill not control the rod scale. Ebeling (92) in 1940 reported that powdered rotcnone-bearing roots give little or no increase in effectiveness of spray oil when used against the red scale, which necessitates the extraction of the rotenone and other poisonous constituents of the root and their being dissolved in the spray oil. However, derris resins increase the effectiveness of the oil, at least to seme extent, if a suitable solvent is used., Such solvents includ dibutyl phthalate, 2 pints per 10 j gallons of spray; Cardolite-627, 1 pint per 100 gallons! and K-58,, 1/2 pint per 100 gallons, bal nut- shell flour mixed with oil-toxicant (2 percent oil plus derris, cube,, and timbo resins), at the rate of 3 pounds of flour per 2 gallons of oil-toxicant pe 100 gallons water, has usually resulted in substantial increases in kill. Cardclite-327 was used as a mutual solvent. The percentage survivals were as follows: Oil alone, 17«6j oil-to:;icant, 7,3: and oil-toxicant-walnut- shell flour, 4.4 Ao nidi ella citrina (Coo.), the yellow scale The California Fruit Groe:ers r Exchange, Bureau of Pest Control (4l) in June 19-38 stated that there lias been an increase of the yellow scale in Ventura County, Calif., in the area around Santa Paula and Fillmore,, The continued use of lew-dosage oil -rotenone sorays nay be partly responsible for this condii .on. The Exchange further reported (43) in "November 1939 b oil- rotenone sprcys at 3/4 to 1 percent of light medium oil will net control in. c:" isrif.a. Aspidiotue pemiciosus Comst., the San Jose scale Cube extract in oil emulsified in water with powdered milk (cube extract 1:12,500; 1.0 percent oil) killed 99.6 percent of the cverwinterin females, !: ; the check oil killed 96,4 percent.— Tumor (_2"2) in 1952. The Leffingwell Company in 1937, in a letter to "E. C. Roark, stated; that "he::- v 2.5 percent rotenone) plus oil has given promising results and| is superior to oil alone. Aulacaspis rosae (Eouche), the rose scale » Rotenone in oil was highly effective. —Turner (27l) in 1932, mam a i i ii m ii.mi ■ nu n i an mi i i i i i i tmamm tf— ■ ... - .75 - ^ Ceroplastes rub ens 1'ask., a pink v/ax scale Ishigai (133) in 1937 wrote of the use of derris in Japan, and argued that fresh' derris roots are nore effective than dried roots. Ground fresh roots plus soap as a spray ?;illed 80 percent of _C. r ub ens on per- simmon and from 80 to 100 percent of various coccidae on orange and pear. On the ether hand, farmers know that if the imported dried roots are used the results obtained are negligible. Something contained in the fresh crude root and lost in the dried roots appears to make the difference. This is an angle not yet studied by scholars, perhaps because of the bad smell of the fresh crude roots, Chicnaspis euonymi Comst., the euor.ymus scale Rotenone 'in oil was highly effective in controlling this species on greenhouse plants,— -Turner (271) in 19 32, Hamilton (136) in 19 38 reported that cube and derris powders (4 percent rotoncnt; and 16 to 18 percent total extractives), applied as a spray at -the rate of 4 pounds per 100 gallons with the addition of 4 pounds of rosin*»residue emulsion, were satisfactory as a contact poison against young scales on euonymus trees, Haude (144) in March 1939 recommended cube or derris powder spray (4 pounds powder containing 4 percent of rotenone plus 4 pounds of rosin- residue emulsion per 100 gallons) for the control of young scales. Chionas_pis furfura (Fitch), the scurfy scale According to Hammer (138), in 1936 results of preliminary tests against C, furfura using powdered derris root and a proprietary mixture of rotenone and .pyrethr'.wi extracts were not promising and were not tested further in 1937, Chionaspis pini f oliae (Fitch), the pine needle scale Rotenone in oil emulsified in water with powdered milk (rotenone 1:25,000, 1,0 percent oil) killed 100 percent of the half-grown females, as compared with 5 percent killed by check oil, — Turner ( 271 ) in 1932. C h r y s omph a 1 u s aonidum (L. ), the Florida red scale Rotenone in oil was highly effective, — Turner (2 71 ) in 1932. LaDue (179) in 1938 reported that in the early part of 1937 labora- tory experiments we re -made using methyl isobutyi ketone, methyl-n— amyl ketone, and 2, 2 T -dichlorethyl ether as intermediary solvents for the derris resinate and tank -mix spray oil. Bbeling found that the methyl -n-aayl ketone-derris-resinate solution increased the toxicity of the oil to (Aonidielia) Chrysomphalus aonidum (L.). - 76 - Coccus pseudomagnoliarum (Kw»), the citricola scale The California Fruit Growers' Exchange, Bureau of Pest Control (37), in September 1937 reported that fumigation tests showed the citricola scale to he resistant to hydrocyanic acid gas, as in the past. Orchards vrith any noticeable amount of this scale should be sprayed with light- medium oil. Growers desirous of reducing 'the use of oil to a minimum might well consider the derris-oil combinations, LaDue (179) in 1938 reported that in the early part of 1937 labora- tory experiments vere made using methyl isobutyl ketone, methyl-n-amyl ketone, and 2, ?J -dichloroethyl ether as intermediary solvents for the derris resir.ate and tank -mix spray oil. The derris resinate-methyl-n- amyl-ketone-oil mixture has been tested on C_, p s e ud oma gno 1 i a rum , The results indicated an added toxicity of the oil to this insect, A paste formed by the addition of methyl-n-amyl ketone or 2, 2* -dichloroethyl ether to the derris powder seemed to increase the efficiency of the material. The Exchange also reported (45, 46) in 1939 that cil-rotenone sprays at 3/4 to 1 percent of medium oil were effective for control of mixed popu- lations of citricola scale and the black scale (§aissetia oleae (Bern.)), Coccus viridis (Green) Bhatta and Parayanan (15) in 1938 reported the v;ork done in Mysore on the insecticidal value of pTar.t fish poisons and other forest products. Alcoholic extracts of seed of Tephrcsia Candida, bark of Mundulea serice a (suberosa), seeds and leaves of Teph rosia villosa, and roots of" De rris elliptica at a concentration of 10 percent in most cases, but much less for the seeds and derris, gave from 60- to 100-percent mortality of (Lecanium) Coccus vir idis Green in 3 to 4 days, in "which period the standard insecticides, nicotine sulfate, and hongay, Pongamia glabra , oil-resin soap, both at 2 percent, gave from 80- to 100-percent mortality. In small-scale .field trials, extracts of seeds of Tephr osia Candida and stein bark of Lundulea seri cea v:erc effective at 2- and 3- percent concen- trations, respectively, against C, viridis on coffee and guava. Water suspensions and alcoholic extracts of derris (7 percent rotenone and 22 percent ether extractives) were effective against Coccus ( Lecanium ) v iridis Green,— rL-ysore, India, Department of Agriculture (203) in 1938. Dactyl coins sp, Schmitt (240) in- 1930 reported derris dust to be ineffective against cochineal insects, Diaspis carueli Targ,, the juniper scale Hamilton ( 156 ) in 1938 reported cube and derris powders (4 percent rotenone and 16 to 18 percent total extractives) applied as a spray at the rate of 4 pounds per 100 gallons, with the addition of 4 pounds of rosin-residue emulsion, to be satisfactory contact poisons against young scales on juniper trees, S^ray with cube or derris powder (4 percent rotenone) at 4 pounds per 100 gallons, plus 4 pounds of rosin-residue emulsion, for the control of young scales. — Haude (144) in 1939. - 77 - Leca nium s, y . Derris or rotenone suspensions were ineffective.— DeBussy et al. (52) in 1935; also (31) in 1936. Not affected by derris. --Van der Laan (178) in 1936 j also DeBussy et al. (5JL). L epidos a phes beckii (Newm. ), the purple scale English (94) in August 1C39 reported on derris as a toxic supplement to oil emulsions for the control of the purple scale on sat s una oranges. Experiments r/ere conducted on potted plants and in the field. Emulsions prepare-;, from several oils and emulsifying agents were used as carriers, No control attributable to derris was obtained with an 83-viscosity tank- mix oil spray as the carrier; however, derris was effective when used with a 41-viscosity tank-mix oil spray and with diglycol laurate. In experi- ments with potted plants derris was an effective supplement to mineral- seal oil emulsions prepared with diglycol laurate, diglycol oleate, sodium oleyl sulfate, or powdered skim milk, or with dried-blood albumen in a tank- mix spray. Although the tank-mix emulsion v.ith derris was the most effec- tive spray applied to potted plants, the increase in effectiveness attrib- utable to derris mas low, and positive field results were not obtained. Greater increases in kill attributable to derris were obtained rath emul- sions prepared from diglycol laurate, diglycol oleate, and sodium oleyl sulfate. Both derris and Derris ql, when used 'as' supplements to a 2-percent emulsion prepared from mineral-seal oil and diglycol oleate, reduced significantly the percentage of scaly fruit on field plots. An experiment with extracted and unextracted derris showed that derris vas a true toxi- cant to the purple scale, Lepi dosaphes ulmi (L.), the oystershell scale Kclndoo, Sieve rs, and Abbott (189) in 1919 reported that derris applied as a dust was of no value against the crawling young of the oystershell scale, Orthezia ins i gnis Dougl., the greenhouse orthezia, or lantana bug Mclndoo, Sievers, and Abbott (189) in 1919 reported that derris applied ae a dust was of no value against the orthezia. Worsley (324-) in 1956 reported as follows concerning bark of Mundulea suberosa Benth. (0.9 percent rotenone) from Moa district, Tan- ganyika Territory, East Africa, and derris root (5.4- percent rotenone): Both derris and Mund ulea bark killed 100 percent of 0. ins ignis at a concentration of 2 percent, but a concentration of 7.5 percent nicotine was required for 100-percent kill, Phenacoccus aoeris (Sign.), a mealybug Derris sprays were ineffective,— Patterson (221) in 1936, - 78 - Phenacoccus gos sypii T, & C,, the Mexican mealybug IJeisvan der ( 204 ) in 1935 reported that a product containing 1 per- cent cf rotenone at 1:200 plus Penetrol at ls200 killed 31 percent of P, £5lS. s 2P.ii on greenhouse chrysanthemums. The jest control, 91 percent, was obtained with Lethane No, 420 at 1:400 plus Penetrol at 1:200. Richardson ( 252 ) in 193-5 reported on the insecticidal control of — .%PJ'^l r P23- on greenhouse chrysanthemums. A derris dust containing 4 per- cent cf rotenone killed 10,5 percent of the nymphs, pupae, and adults, and 7 percent cf the eggs-. A derris extract diluted to contain rotenone 1:10,000 by weight plus other derris extractives was mixed with potassium- ccconut-oil soap (0.33 percent dry soap o^ weight). This spray hilled ,5 percent of the nymphs, pupae, and adult:;. The same derris extract plus C ,6 percent by volume of a sulfonated petroleum oil [Fsr.etrol?] killed 15,5 percent of the nymphs, pupae, and adults, Tnc Pest control (97«3 percent) was obtained by a 10-percent emulsion of kerosene. ■Pspudo coccus brevipes (Ckll.), the pineapple mealybug "hatarabe ( 501- ) in 1936 reported that derris sprays have proved of son.- value in the control of P. brevipes on pineapples in Formosa, Pseudoccccu ?' dtri (Risso), the citrus meaJLybug.j a greenhouse mealybug Mclndoo, Sievers, and Abbott (IPS) in 1919 reported that derris applied r~. a dust was of nc value against this nealybug, Derris has e,iven irregular and rather unsatisfactory results. — hope (176) in 1924. Rotenone suspended in water ( 1:250) killed only 25 percent and a dust of 2 parts of rotenone and 95 parts cf diatomaceous earth killed none. — Davidson (65; in 1930. Rotenone in oil was highly effective. — Turner ( 271 ) in lW5Z m A ro ten one-pyre thrum spray containing 0.75 percent of rotenone and 1.8 percent of pyrethrihs at 1:200 reduced the infestation 74 percent, as compared with a S9-percent reduction obtained by Lethane Ho, 420 at 1:800 plus soap 1:250. Three applications were made at intervals of 1 weeS on these ciealybugs infesting colons. — Neiswander (204; in 1S35. Ps eu cococcvs c c;.is t och i (Kuwv), the Cons took mealybug P.ivnay ( 253 ) in July 1939 reported on the control -of P. corns tocki on citrus in Palestine. A proprietary insecticide containing derris and pyrethrum gave an unsatisfactory raortalityj so did also another brand containing derris alone vh.cn used at the rate of 1:500, as directed by th e manu fa c tur er s , Pseudoc cccus zp> + Rotenone sprays were ineffective agairst a mealybug on parrotfeather ( Myriophyllura ) , The rotenone suspension was prepared by aiding a solution of 0,2 gm, rotenone in 5 ec, benzene and 95 cc. Penetrol to r.ater to make a concentration of rotenone 1:100,000 olus Penetrol 1:200. — Darley (62) in 1931. ' ^MMBMBt. - 79 - Foliafume (a pyrethrum-derris spray rath spreader) at 1:400 killed 85 percent in 48 hours,,— -Penick and Conp'any (25jf, in 1936. Devris or rotenone suspensions vrere Ineffective,— DeBussy et al. (J52) in 1935, (31) in 1936, Not affected by derris, — Van der Laan (17?) in 1951; DeBussy et al. (31) Pul Tr inaria vitis (L. ), the cottony maple scale Hamilton (153) in 1938 reported cube and derris poivders (4 percent rotenone and IS to 13 percent total extractives) applied as a spray at rate of 4 pounds per 100 gallons vith the addition of 4 pounds of rcsin- residue er.ulsicn to be a fair contact poison against this insect on maple tree.:. nicotine is totter. Saissctia h emispha erica (Targ. ), the herd spherical scale Rotenone in oil vas highly effective. — Turner ( 271 ) in 1932. Saissetia oleac (Eern,), the black scale The Bureau of Post -Control of the California Fruit Growers' Exchange, in the November 1935 issue of their Post Control Circular (54) reported results of tests v/ith nex; citrus sprays against uniformly sseall black scales, as follovra: Average Material and dosage Amoun t of oil added mortality Percent Ortho Derris, 4-5 lb. 0.5 pet, light-medium to per 100 gal. 0.S7 pet. medium 99,06 Regular oil spray 1,67 pet. soluble or 2 pet. emulsion • 99.7 Ortho Derris, sold by the California Spray Chemical Company, uus the nest - 1; used spray of the nonoil materials during the regular black scale s . A considerable number of groves i.-ere treated -huh satis- factory results; although, as shov.u in the last column of the table, it u-as someurhat less effective than the regular oil sprays, ho date no injury by this sg-- ' has been observed en either or ripe fruit, or or foliage, Tox-X (2 b .: percent rotenone) at 1 pound per 100 gal n u s >lus 0,5 to 0.37 percent light-medium or medium oil killed £9,1 percent of small black scale. Against black scale Tox-h vjas equal tc Ortho Derris but not guite so effective as regular oil sprays. In ist 1936 issue sf Pest Ocntfol Circular (35) re r lug so-called nonoil sprays, it is stated that Crtho Derris -' are composed of a poudered insecticide coni ; derrii - ' ' losage of light medium oil, usually 0.5 to 0.67 perc . Largel; - cJO - cooler coastal areas, these sprays ^ave satisfactory commercial results against i7rn0.tu.re llac'" scales, beir.3 onl ■ slightly less effective than the commercially used black scale oil sprays at ordinary dosages-. At slightly higher oil dosages, up to 1 or 1.25 percent, off-hatch scales were effec- tive! : ills ! i.n a ni ■ of orchards-. The particular advantage of these sfr black scale at that tine aas that they appeared to be sai r for use on nature Valencia fruit tr a: straight oil sprays, produced ■ less oil effect cr the tree, and also checked aphids, if present. To date, derris sprays with 0,5 percent of light medium oil have shown litt! oil deposit, no interference with color, and ability to control the black scale s a t i s I a c t o r i ly „ The California Fruit Growers' Exchange, Bureau of Fest Control, (36, - . ■ . . , 46)j in August 1937 stated that in Ventura County, Calif,, b bed 3 ' lacl scale area in Bardsdale and Ciai 1 be handled by ore of the d orris-oil sprays, with fewer adverse effects than the regular oil sprays. Also where it is impossible to fumigate overripe fruit without serious damage the derris-oil sprays might be used. The Lbzchs ige in February 1933 recommended cil-rotenone combinations for combat j e block scale associated v. r ith the red spider and the citrus aphid. A s\*i table spray is made from 0.5 to 0.75 gallon of light medium oil, 1 to 4 pounds of rotenone powder, and water to make ICO gallons. In July 1938 growers of oranges in Ventura County were advised that low- dor: rris-oil will handle the black scale and is easier en the trees ana Fr It, and in 1938 it was reported that oil-rotenone sprays had shown definite value not or] .7 in killing snail black scales but, in off-sea work, in destrc larger scales than did emulsions or emulsibles with the same amount of oil. The exchange stated. that in September 1939 light medium oil, medium oil, rotenone-oil sprays, and fumigation were methods largely used for control of S. oleae, according to the district; and in November 1939 the Exchange reported that oil-rotenone sprays at 0.75 to 1,0 pe t of light medium oil are effective for mixed populations of the citricola and black scales. Oil-rotenone spray was more effective on advanced black scales than was raiscible oil and lime-sulfur and is less likely to retard coloration than straight oil, Mien used vrith oil, Tox-X is very effective against citrus black scale and is superior to oil alone, according to Leffingwell Company in a letter to P.. C. Roark in 1957. Boyce and Frendergast (19) in 1933 wrote that the oil-rotenone mixtures are relatively expensive -.hen considered for the control of red spider alone. However, when considered for the combined control of ads, red spider, and off-hatch black scale during the spring, they are very prac bical LaDue (17.9) in 1938 reported that pastes of derris with vari us .nic solvents added to oil sprays gave unsatisfactory results against £• <) ^ eae l on Washington ravel orange trees. Acetone and. ethyl ether- derris extracts wore also used, with low percentages of spray oil, but certain difficulties were encountered, such as the resins flocculating and going out of the oil phase into the aqueous phase. In "ohe early part of 1937 laboratory experiments were made using methyl isobutyl ketone, mcthyl-n-amyl ketone, and 2,2'-dichlorethyl ether as intermediary solvents ^■■■■■■■^■■■■■MHii^HriMaHMU - 81 - for the derris resinate and ta -- ix oi'I. The derris resinate-meth r l« n-anyl-ketone-oil mixture has been besi .. the black scale i bhe results indicate an added toxicity of the oil to this insect, ft by the addition of methyl-n-aiayl ketone cr 2,2 ? ~dichlcrethyl ether to the derris por r der seemed to increase the e . the material. Ebeling (92) in 1940 reported bh cone-be •-: ; roots have been used in California for a numb< ■ incr f: c- tivencss of spray oil against the black scale. They hav ter possible a reduction of oil dosage from the u c i^ n 1.5-1,67 percent tc 1 percent or less, C o c c i da e ( un i d e nt if i ed species ) Coccidao in general are not affected by derris. — ' ■ Laan ( 178 in 1956. Van der Yecht (287) in 1933 reported that r_ ?rimc: ts v. r ith derris inst Ccccid'.e had so far failed to give satisfactory result's. ,Uiil o From 80 to 100 percent of various Coccidae on oras - r.d pear - r r.r? killed by the application of ground fresh derris roo - 3 lus soap jas a spray. — Ishigai (163) in 1937, Mealybugs Corbett (52), entomologist for the Federated ?.'.al . s Depart- ment of Agriculture, reported in 1^30 that tv? used at the rat's of 1 pound to 10 imperial gallons of Crater is a go< i: secticide for general use in the garden, as plant., regularly tprayed v. r ith it r.dll be kept com- paratively free from mealybugs. Laidenhair fern a'nd similar plants are often diTcrfed in ;-ro~.doh by mealybugs: a tuba spra 1 v/culd be found very V satisfactory in controlling them, Jones and Davidson ( 164 ) in 1931 report" t rotonone rris extracts prepared v/ith r ish oil have a high toxicity to mealybu . Davis (36) in 1932 rrrote that •if. penetr ting niscible oils derris has proved very effective inst mealy The Rubber Service Laboratories Company, a subsidiary oi the Monsanto Chemical Company (238) in 1935 reported that - ray cor gaining 7 rts of derris resins, 33 parts iry Aresco, :o rt: ' e cil (or oleic acid) is effective against i lybi ;s it 1:200, The " or/in - mixture at 1:200 v/as found to he effective: Dorris-rcsin 7 parts by 'vveight, dry Aroskap 52 parts, and cither pine oil cr oleic acid 60 ..arte. - S3 ~ A Method of Testing Oil Insecticides R. H, Smith (248) in 1358 described a microtechnique method of testing oil ihsectlcici es on scr.le insects. Thin involves placing the oil directly into the spiracle of the insect, cr upon any desired part of the body, and determining the effect by observation under the micro- scope. The me ■' has been employed with particular satisfaction in studies ritb hi hly refined oils fortified by the addition of pyreth.rur.ij rbtencne, and other substances to make the oils toxic. Its usefulness can probably be enlarged through the use of micromanipulating apparatus cf the type employed in the field biolo or. Ful^oridae S c ga ta fu re if era ( ho rv. ) Spraying with derr.is effected complete control of this insect attacking padi (rice) in "thq Federated Malay States, — Federated Malay States Department of Agriculture (100 ) ir 1937. Llembracidae Ceresa bubalus (F.), the buff a] lopper A dust containing 2 r 5 parts of derris (3,95 percent rotenone) and 75 parts of gypsum was ineffective »~*Eelsall and Stultz (170) in 1937, Glossorxotus cr i f H ; , a treehoppe: i i Hutson ( 158 ) i ' reported that nicotine, der,ri3j and pyre thrum dusts had no effect on adult treehoppersy 0. cfrataegij en plum and apple, St jo tc c ephala festina (Say), the three-cornered alfalfa hopper Cassidy and Barber, of the Division of Cotton Insect Investigations, Bureau of Entomology and Plant Quarantine, in 1935 reported that cube dust ve 80 percent control, derris dust (4 r • rotenone) C>5 -percent con- trol, and pyre thru >ercent control of this insect on cotton in Arizona, Tests re re made in cages in the field and also in lantern globes in the insectary* These results were cited by Loark (234) in 1930 in comparing insecticidal value of derris and cute. Membracidae (unidentified s i . • a i e s ) Bhatta and Narayanan (15) in 1937 reported the work done in Mysore, India, on the insecticidal value of plant fish poisons and 'other forest products and stated that an alcoholic extract of the seeds of Tephrosia Candida, at 1 percent concentration, controlled adults and nymphs of membracids on Qaianus ihdicus. Psyllidae Faratrioza cockerelli (Sulc), the potato psyllid,, or tomato psyllid The Ner; Mexico Agricijltural Fxceriment Station (208) in 1954 recorded the results of spraying experiments /or control of the potato psyllid in the field. Comparisons v:ere made of bordeaux sprays, bordeaux-oil-nico- tine sprays, and bordeaux-rotenone sprays. Irish Cottier potatoes at Bluev.ater, N, Mex., arere treated v,dth the acid-mercury dip a planted on the horticultural and Stith Farms on February 27, 1333. One secti< of the potatoes at the Horticultural Farm vras sprayed three time ~ ' bh a 5-5-50 bordeaux mixture, another -.1th bordeaux mixture containing 1 of Volck oil and 1 pint of nicotine sulfate to each 100 gallons of s; r .y material, and the third plot -..1th a 5-5-50 bordeaux rixfvre to - ' c~ . been added 1 pint of rotenone extract. The potatoes on the Stith Far v/ere sprayed r.ith oil-nicotine and the bordcaux-oil-nicotine. There ". s a very noticeable difference in the yield between the sprayed and unsprayed sections, as shear, by the following data: Yield of potatoes per acre Bo.'T HbV'Y Treatment grade j rade Cull Pounds Pounds Bordeaux only ~T,4l3 919 Check, not sprayed ----- 1,033 392 Bordeaux, oil, and nicotine- 2,478 1,219 Check, not sprayed 1,679 1,002 Bordeaux and rotenone- - - - 2,033 1,131 Check, not sprayed ----- 2,112 1,130 Psylla pyricola Foerst,, the pear psylla Neoton (derris extract in fish oil), 15C gra. plus taice its v/eight of soap in 40 imperial gallons water, killed 100 percent. — Institute Physical and Chemical Research ( 132 ) in 1927. Van Buren (286), in ansv. r er to questi as sent in by growers at the York Horticultural Society Annual Meeting in 1923, stated t] Derris ol "as effective for the control of -pear psylla, Hartzell (145) in 1930 reported that when a commercial pear orchard infested with nympns of the five ir stars of t] r psylla ; ed by means c." a large sore;-' rig maintaining 330 pounds pressure, D r 1:533 alore vas not very effective (53 percent 'rilled) But t] : Lon of bordeaux brought the killing efficiency equal (92 percs t ki] i) to ■ of the regular spray, -ehich consists of 2 pounds of corper sulfate, 40 pounds of Iterated liee, ant 1 pint oi nicotine sulfate to 100 pallors of v/ater. Trees ax re treated vlth a dust contain: rts of derris (3.95 percent rotenone) end 75 parts oj -. Most of the ueults flea- away and es'caoed at the time of dusting a lost cl those aid fall re< v ■ later. Bymphs mere very sloa- in dropping and Bat ft dropped at the end of 24 hours. Two veeks after treatmei : ris-treatcd trees vrere practically free from nymphs, which rere still a check trees, — Felsall and Stultz (170) in 1937. - 84 - Pnylla sp, Carlos ( 47 ) in. 1926 reported that Psylla is one of the chief insect peeve that car. be easily exterminated by the application of insecticides containing derris or its products. An anonymous vritcr (2) in 1950 repcrxrd the aqueous extract -of derris root to be effective against £.syliids. Worsley (324) in 1336 reported concerning bark of Lluhdulea suberosa Berth. (0.9 percent rotenone) fro;. 1 Lioa district, Tar: yi a Territory, East Africa, and derris root (5,4 percent ro ten one)", that the follovdng concentrations are required to kill 100 percent of a species of Tayl la infe : L: ; citrus in Amanis 0,45 percent of Fundi.'; lea bark, 0.S5 percent of derris root, and 0.25 percent of nicotine. Psyllids on pear trees v. r ere killed by a proprietary dust con- taining 12 percent of cube of 6 percent rotcnone contort, according to a letter to R. C. Poark from Eta'bliss omenta Rotenia in 1938. - 85 - INSECT IJJDEX .rage Adelges abietis. See Cherries a biet is. sp. - "TV- - - - - -~~ ~V _ ~ . _ _ _ 64 Aley rodes sp. ------------ --------------- 4 Aleyrodidae --------------------------2, ,3 A nuraphis — oardui- --------------------------- 4 ma idi- rad i c i s ------------------------ 4 per sicae-n iger- ----------------------- 5 roseus- ---- — --- — — - — — ---■----------- 5 tulipae --------------------------- 5 A o n :i d~i"eTTa- - aonidum. See Chrysomph alus aoridrm aurartii- ------------- ------------- 72, 73 citrina ------------- — ___________ 74 Aphid's-"- ___- 4-63, 80 Aphids en — abaca ---------------------------- a« apple -------- _-..-__----_--------- 50 beans ---------------------------- 60, 62 birch ----------- 50 broadbear ----------------------------- 10 cabbage -------------------- -- --- 18, 45, 51 cauliflower ------------------------ 45, 51 celery- --------------------------- 3 Ceylon iromrrood ----------------------- 51 cherry- - - - - _-----_--_-- 51, 62 chestnut- -------------------------- 52 chrysanthemum ------------------------ 52 citrus- ---------------- -----------52, 53 corn- ----------------------------- 53 cotton- --------------- --------------4, 6 currant --------------------------- 53 dahlia- ---------------------------- 62 d"warf spruce- ------------------ ----- - - 55 eggp? ant- -------------------------- 53 flowers --------------------------- 53 fruit ...-_-_ „„_ 5.3 goiderrci -------------------------- 54 grape -------------- _-_______„__ 7 head lettuce- ------------------------ 54 hops ---------------------------- 54 Japanese maple- ------------------------ 54 lima beers- ------------------------- 50 lotus ---------------------------- 54 mustard --------------------------- 47 nasturtium- ------- ---------------- 13, 54 orange- --------------------------- ornamental cherry ---------------------- ox-eye daisy- ---------------____-___- 54 pansy* -«-------------------_--_--- 58 - 86 - . Page parsnip- -----__--- — _ _ .. _ — _>_.„____ _^ 20 peanut ---------."---...'.----__ -_____- 55 pear ------.--.-..-•------'----___■'---- 55 plum -. -', .. -.-,-/- __„____- 55^ Q2 poppy- _ - - - - _-_„-__- __ 62 raspberry— --_--.----___------__-___ 55 rose --"-■--..--..--.-----.------------ 55", 62 soybean- ----.---____-___--.._---_..__ 56 spinach- ---'--..-.-.---••--■_■-__'-..---_--., 45 Spirea vanho u 1 1 ei- ---------------------- 56 strawberry ------------------------- 56 tea-- ----_--________ ..„_-___-____- 50 Ehistle- ■ ■ - .-____-_„--__„„-__-- 4 tobacco- ________ „ - 43, 44, 56, 57 tomato ' __.. __ -40, 58 tulips --------------------------- 5 tuliptree- -------------- - _-_- 23 turnips- ---------------------------47, 48 viburnum -------------------------- 58 violets- ---------.«------_---__---- 58 white, pine -------------------------- 58 Aphiida.e - - -4, 50, 52, 63 Aphis— - aye nae . See R hopalo s iphum p runjf ol iae . gossypii -------------------------- 5"* 6 hel iantK'i- -------------------------- 7 ill ino is ens is- ----------------- — -____ 7 ~?aedicaginis- ------------------------ 7 nerii — ____.,._______________--_-__ 8 odinae -'----------------------••- - 8 papa veris- ------------------------- 8 pcni ~" ' -5, 8; 9, 10 pseudobrassicae, S.?e Phopalos iphum speudobrassicae . rumicis- -------------------------- 10 sambuci- -------------------------- 15 spiraecola --- --------- ------- ______ 2.-5 1 17 sppT ™~~ - - - ,- .--- _..___-_-__---_ 59 4-n^O^oo-i __„..___- 17 i..E.jS.res_ __—__,. — ——— — — —— — — — _ — ——-_——— ±t Aphrophora permut&ta --------------------- 63 Apple — aphid- - - - 8, 9, 50 leafhcpper ------------------------- 68 Apple grain aphid- ---------------------- 46 Arrowhead, aphid s ----------------------- 59 Aspifliotus pernic iosus -------------------- 74 Aulacaspis rosae ----------------------- 74 Bean _. _» aphid ; 10-15 leafhop-ier 55 Beet leafhcpper- ----------------------- 70 ■ - 7 - Page £52 Black- aphid -------------- — - - ------- -l.'j, 60, bean aphid- ---------------- --------- 12 cherry aphid- ------------------------ 42 citrus aphid- -------------------- - - - - 40 peach aphid ---------------------------- 5 plan t lice. See Aph i d s . scale ■ - - ..-_-__ 76, 7 , , 1 Breviccryre brassicae ---------------------- -IS, 44 reehopper- ----------------------- Cabbage — phid -_„.. -18-20, Trams ---------------------------- 20 California red scale --------------------- 72-74 Canary fly- ---------------->--------- - 71 Ca'pitophorus— f'rarariae --------------.------------ 20 rib is --_--------•-«---------.«•------ 20 rosarun ----------- -- -------------- Caterpillar ----------- --------- __..__ 10 CavajrjLella sp.- ' - •- ---,__--- — - - - 20 Cercopidae- ------------------------- C3-G4 Ceresa bubalv.s- ------------------------ 82 Ceroplastes rubens- ----■--_-/- 1 -'---_-----_-- - 75 Cn crimes-- abie_ti_s -------------.*---------_., 64 cooleyi --------- — ___-_______„____ S5 sp. ------ -_---_.. ____„___„_ 65 Chermidae _-____.._„_„_-_ (54 Cherry aphid- -------- -------------- -42, 43 Chevi:: ig insects ----------------- ------ 3, 47, 52 Chionaspis— ev.onymi --------------------------- 75 fv.rfura „__ _ 75 pinifoliae- ------------------------- 75 Chrysantheiriur.i aphid ----------------- — -_- 22 Ch r y s op p I \ 3. lu s — acnidvn --------------------------- 75 av.rar.tii. See Aoni diella aurantii . Cicada, periodical ----------------------- 72 Cicadellidae -_-_----_-_---_-__- -65, 71 Cicadidae --------------------------- 72 Cinara sabinae- ------------------------ 21 Citricoia scale ----------------------- -76, GO Citrus-- aphid 16, 49, 52, 53, 80 black scale ------------------------- 80 nealytmg- -• 73, 1 red scale ------------------- ------- 72 dtefly- ------ — .. — ------ 2 Clartoptera sp, ------- --^-----.. -------- 63 - 38 - Coccidae- - - - -.-■ — ~ - - - -.-• - - -• - ---■-.- - -■ - -72/~81~~ Coccus — pse udozaa gr.pl iaruir -'- - --.------,...-- „..__..__-_ viridis ----..__.._..- „^. ._„„„_ .. _ „___„_ Cochin eal Core :?Iov r ;ora 'OO" ;S -.- - ap] rid - - - ^hid - - - - Cotton — aphid • 2'co"o apnids ------ Cottony maple scale - - •■ Cprpea aphid- -------- Cranberry spittle insect- Curra: ;hid v '-«•-- - Dae 1( ipt-yicpius s; Dial eu rod es- - chittend citri „ _ _ Diaspis c&rueli ------ Er.ip oa rosae. See Typhi ocybt Ekapoasca— . sae, iaoae - - - - - ma 1 i gna - - • ■ - Eriosoma 2 ait geru: "Erj ■':".:• - "a-"- * co ies --.- — - pa- !"P, Eucnynus scale- - - '•• - Supteryrc fla-ro scuta ■ Eutetti:: tenellu's - - - F .'.lc 3 c.V; '•. e s p lid - - i Tc Florids red seals - - ------------ --~~--_~_ ■idae- --------------------- ------ Glasshci5.se leafhopper --------------------- Glessonotus crat aegi ---------------------- ------------------------ p.o leafhopper- - - - - ------------------ - — aphid ..__... -__ „_..__ „4c, .41 , 51 apple aphid ------------------------ citrus aphid- ------------------ -^t/« §L£ --1- ^-- s • "ceacW v.xjjii d— — — — — — — — ——— — — — — — — - "ocr to apj id ------------- ------- rose aphid ------------------ Greenhouse — 76 76 76 41 4 7 4 79 7 63 2C 76 2 2 76 68 21 68 68 69 75 69 70 47 75 82 08 82 41 68 7 51 ./■.;•; 4A mealybug orthezia vjhitefly 62 , 9 16 45 39 41 78 77 3 ■ >B -7 i W i!-r: ■- ^,-.v , -., ,»« - 89 - Page Hemispherical scale- ------------------ - - - 79 Homoptera- -------------------------- 2, 63 Hop aphid- -------------------------- 46 Hyalopterus- - arur.dinis - ------------------------- 22 prurii . See H. arundinis . Hysteroneura s etariae- -------------------- 22 Id iocerus sp, ------------------------- 70 Indian mustard aphid ------------- -------- .47 Jassids --------------------------- 72 Juniper scale- ------------------------ 76 Ladybeetles- ------------------------- 39 Lantana bug- ------------------------- 77 Leaf— aphids 53, 54, 57, 61, 62 lice -._-,-.- „__-__ 51, 56, 60 Leafhopper -_- _ _- -65-67, 71 Leafhopoer on — applel „___ 68, 71 beans- --------------------------- *65-67 beet -___*.- _ 70 dahlias- -------------------------- 66 grape-c- -------------------------- 68-69 potatoes -------------------------- ,65-67 rose---------------------------- 71 Lecanium sp. ------------------------- 77 Le'pidosaphes — beckii _ _ - _ _ 77 ulmi _-------__--- ....__„__- 77 viridis . See Coccus viridis . Lice. See Aphid s, Macro s iphoniclla sanborni ------------------ 22 Lac rosiphum^ " ij 1 ino i s e_r, s i s . See Aph is illinoiser.sis . l_iri_od_endrJ.« '------ ----------------- pisi _» - ____--__- __„_______..______ rosa e ---------- --______-__„_-___ 41 rudbeckiae- ------------ ____________ 41 solanif o lii ------------------------ 39 Volid a ginis ------------------------ 42 Macro steles d i vi su s --------------------- 70 Magi cic ada septen decim- ------------------- 72 Mango hoppers ------------------------ 70 Mealybug _____ __ .77, 78, 81 Mealy plum aphid- ---------------------- 22 Melon aphid ------------------------- 5 Membracidae ------------------------- 82 Mexican — bean beetle ------------------------ 50 mealybug ------------------------- 78 Mosquito larvae ----------------------- - PO - Page Myzus — cerasi -----------_--.___-___-- _„___ 42 persicae -------- .-..- ----- ------------- 43 Nasturtium aphid ------------.~ ----------- 54 "Norway maple aphid - - -.-..--.-.,- ----- — _„__..___ 46 Orthezia in sign is- ----------------------- 77 Oyster shell scale ----------------------,- 77 Parat rioza cockerelli- --------------------- 83 Pea aphid- - - ■ .-- — __--_'__- 23 Pear psylla -------------------------- 83 Pent a Ionia nigr on ervo sa- -------------------- 43 Periodical cicada- -------------------'---- 72 Periphyll us lyr opictus --------------------- 4-6 Phenac occ us — ■aceris ----------------------------- 77 gossypii ------------_-___---------- 78 Fhilaenus — - leucophthalmus ------------------------ 64 "|" fal len! - -------------------------- 64 eibbv.s --------------------------- 64 j ustulatus- ------------------------- 64 spumarius . See P. leucophthalm us . r falleni . Sec P. 1 euc ophthalm u s fallen !. jibb_us. See P, 1 eu c cph t haluru s gibhus. ustulatus . See P. 1 euc c phtnn linus ustulatus ■ Phorodon-- humul i - -------------------------- 45 ( Myzades ) persicae . See Myzus persicae . Pineapple, mealybug ---------«----------.--- 78 Pine needle scale --_-_-____--_-_----.---- 75 Pink— aehids - . -40, 41 v/ax scale- -------------------------- 75 Plant lice. See Aphids. ... Plutella maoulipennis ---------------------- 51 Potato— ~ , ~ .. aphid- -.---_-_--_---- ^- ------------ - -,- - 39 leafhopper --------------------------- £5 psyllid ------------------------ 83 Pseudococcus — - ,. - ■ . . brcvipes ----------------------- --■*..- 78 citri ------------------------- --- 78 comstocki- ----------------*----------.- 78 ip- c r-inr- . _-.._------- 78 Psylla— ricola --------------------------- 83 tp7~r-r „ - _ , __„__.„„„- 84 Psyllidae „„__ .. „__ 83 Ptero jhlorus tropicalis- -------------------- 46 PvJ vitis - -"^~~ - „„_--_--- 79 Raspberry beetle ------------------------ 55 asai - 91 - Page -Red- aphid - - - - 54, 62 cedar aphid- --'--------------■------- 21 potato aphid ------------------------ 40 scale 72-74 spider --16, 53, 80 Rhc -odendron whitefly- ------------------- Rh o pal o s i rh um — prunifoliae -------'-■---------------- 46 pseuclobrassicae- -------------- ------ -20, 47-49 sv 49 i- • * 3 subt cr^r neum ----------------------- 4, 49 Root aph ..as- ------------------------ 4, 50 Rose — aphid - ------------------------- 41 leaf hopper - - - - -------- 71 pests -- ------------------------ 55 scale - . — ______ 74 Rosy- aphid -------------------------- 5 apple aphid ----------------------- Rust mite ------------------------- 16,52 Rusty plur. aphid ---------------------- 22 Saiccetia-- hemisphkerica ---------------------- 79 oleao- ~-~ ~- -75, 79-31 San Jose scale ----------------------- 74 Scale insects ------------------ -52, 73, 75, 76-31 Scurfy scale -____-_--__--___--_---_ 75 Siphoccryi'.e indobrassicae . Sea Eho pal o s i phum ^seudobrassicae. Siphoncphora rosae. See Macro siphum rosoe. Six-spotted leafhopper ----- -""-" T" - - -__„__--_ 70 Slaty- pray aphids- ---------- ~ ---------- - 51 So g at a furcifera ---------------------- 82 Spinach aphid ----------------------- 43 Spirea aphid ------------------------ 15 Spittle bugs ------------------------ 64 Spruce gall aphid --------------------- 64 Stictocephala f estina- ------------------- 82 Strawberry — aphid ---------- -__ __ -__-_ 20 spittle bug------------------------ 65 Sucking insects- --------------------- -9, 58, 60 Thistle aphid ----------------------- 4 Three-cornered alfalfa hopper*- ------- -------- Tobacco — aphid 43, 44, 56, 57 pests- _-----_---------.--_-----_.- 57 Tomato psyllid ----------------- ------ Tcxoptera aurantii --------------------- 49 Treehoppor ------------------------- 82 Irse lice ---------------- — - - ----- 58 Trial eurodes — sp.' 4. vap ora riorum ----------------------- 5 52 - Trr.f ida phis phaseoli ------- ^Tjjy~^ ; ^r "-~t~"~j - — .. = _ T"uliptree aphid- --------- Tuv t3 -------- - - • - ■e Ery*bhrorif:"ur8 ocmes ?iDn pie les i sr ------ Tilhitefly ---.----,-- - - - Woolly— Pag< 47 71 71 71 71 2. 3 arvol e 21. g; ia- Yellow re 3.1'e 21 74 ■Hlfci..J . - 93 - LITERATURE CITED (1) AHONaiOUS 1927. Schadlingsbekampfung rait Derris el" 1 . iptica. 'weinbau u. Kellerw. 6: 108-109. (2) 1930, Pondered derris root. Pharra. Jour, and Pharm. [London] 124: 563 (3) ALABAKfc POLYTECHNIC INSTITUTE 1935. The use of derris in controlling garden insects. Ala. Polytech. Inst., Agr. Expt. St?., Dent. Zocl.-Ent., 2 pp. [Processed.] (4) 1923. The effectiveness of powdered derris root v.ith various carriers against citrus vhitefly, Dialeurodes citri (Ashn. ). Ala. Agr. Expt. Sta, AnrTTpt. (19 34-35) Bui. 46: 20-22. (5) ALLEN, N. 1933. Results v/ith rotenone dusts and sprays. U. S, Dept, Agr., Bur. Ent. and Plant Quar. News Let. 234: 7. [Processed.] (6^ > — 193-1. The turnip aphid, U. S. Pent. Agr., Bur. Ent. and Plant Quar. Cir. E-324, 3 pp. [Processed.] (7) AMSPICAN ASSOCIATION 01 ECONOMIC ENTOMOLOGISTS 1957. "Entoma", a directory of insect pest control. Amer. Assoc. Eoon. Ent., Eastern Branch. [C. C. Hamilton, ed.] New Brunswick, F. J., 142 pp. [Cube-derris, pp. 44-46; rotenone, p. 65.] (3) AMSTERDAM KOLONIAAL INSTITUUT 1950. Toeba-wortel, Inlichtingen en onderzoekingen van de "afdeeling handel'smuseum in 1929, Amsterdam Kolon. Inst. Afd, Eandelsmuseum. Meded. 26 (8): 91-99, illus. (See also Kolonial Instituut fe Amsterdam.) (9) 1 : "SC ;, L. D., and ?.!MJ I , H. G. I 1 ., d. Control o f : lies or gardenias. Jour. Econ. Ent. 32: 210-212. (10) ANDRIES, I : . E. 1932. Controlling Plant Pests in Southern Africa. 19 r , pp.» illu s . Johannesbu r . (11) BADERTSCHER, A, E. , and TTTEEESPOCN, P. 1935. Derris and pyre'd owders, a study of their protection from injurious action of li md air. Soap 11 (4): 87-89, ill, 112. - 94 -. (12) 5ARFC0T, J. A. 1935. The progress of rotenor.e. ITest, Grov/er and Shipper S (6): 13, 18. (13) BASINGFE, A. J. , and BOYCE, A. M. 1936. Oran.ge t/onas in California and their control. Jour. Econ. Eat. 29: 161-163. # (14) BETREM* J. G. 1931. Enkele verdere gegevens omtrent derris, als een insec- ticide leverende plant. Sericultures 5: 759-761. (15) EHATTA, K. L. , and NAMYASA1J, B. T. 1S38. Report of'vrorh dene in Mysore [India] on the insecticidal value of plant fish-poisons and other forest products. (L'rcn April l c 56 to Larch 1C57.) 25 pp., New Delhi. [Abstract in Rev. Appl. Ent. (A) 26: 360-561.] (16) BOCK, C. 1934. Derris elliptica. Deut. Apoth. Ztg. 2: 588-589. (17) BOURCART, E. 1925. Insecticides, Fungicides, and Weed Killers. Trans, by T. R. Burton. English ed. 2, 451 pp., illus. London. (18) BOURSE, A. I., and BOYD, 0. C. 1937. Pest control in the hone garden. Mass. Agr. Col. Ext. Leaflet 171, 12 pp., illus. (19) BOYCE, A. ?:., and PRERDE.nGAST, D. T. 1938. Control of citrus red mite (spider). Calif. Citrog. 23: 370, 3S8-400. (20) BRADDOCK, D. 13. 1930. The demand for tobacco insecticides in the East Coast of Sumatra. U. S. Bur. Foreign and Dom. Com., Chcm. Div. Spec. Cir. 305, 4 pp. [Processed.] (21) BRITTAIN, W. K. 1925. ~ Some miscellaneous insecticide tests. Acadian Ent. Soc. Proc. (1924) 10: 23-42. (22) 3R0RS0H, T. E. 1936. Derris dusts impregnated v;ith a spreading and v:etting agent she:: increased efficiency against pea aphid. U. S. Dopt. Agr., Bur. Ent. and Plant Quar. News Let. 3 (5): 18. [Processed.] (23) 1936. Effect of ground derris upon pea aphid "when infesting peas subsequent to spraying. Jour. Econ. Ent, 29: 1170-1172. - 95 - (24) — 1936. An improver 1 apparatus for mixing insecticidal dusts. U. S, Dept. Agr., Bur. Eat. and Plant Quar. ET-93, 4 pp., illus, [Processc : n . ] (25) 1937. Ar efficient method for mix: Large or small quantities of insecticidal dusts containing a conditioner. IT. S, Dept. Agr., Bur. Ent. and P] ; Qvar. 3T-115, 3 pp., illus. [Processed.] (26) 1937. Comparative efficiency of different spreading, vetting, and sticking agents used with rotenone compounds against pea aphid. U. S. Dept. Agr.', Bur. Ent. and Plant Quar,- News Let. 4 (2): 20. [Processed.] (27) 1958, A method for mixing insecticida] dusts containing a condi- tioner. T J. S. Dept. Apr., Bur. Ent, and Plant C„uar. E-443, 5 pp., alius, processed.] (28) and DUDLEY, J. E. , Jr. 1938. Conditioning agents for increasing the effectiveness of rotenone-bearing ousts against the pea aphid. Jour, Scon, Ent. 31: 419-419. (29) — and ST0i T E, F. V. 19 38, Peanut— oil emulsion added to derris-dust mixture aids in pea aphid control. U.S. Dept. Agr., Bur. Ent, and Plant Quar. News— Let. 5 (o): 18. May. [Processed.] (30) BROOKS, A. U., YATSCB, J. R., and I'OYDY, H. 1932, Strawberry production. Fla, Univ. Apr, Ext. Bui, 63, 51 pp., illus . (•31) EUSSY, L. P. de, LAAN, P. A. van der, and DIAICONOFF, A. 1956, Bestriiding van nederlandsche insecter met derris. Tijdschr. over Plantenziekten. 42: 77-100, illus. (32) — LAA7, P. A. van der, and JACOBI, E. F. 1935. Resultaten van procven met derrispoeder en rotenon op nederlandsche insecten. Tijdschr, ever Plantenziekten. 41: 59-50, illus, [Also ir Amsterdam Kolon. Inst. Afd. Hand el smu seven, Ber. 91, 25 pp., illus.; and Indische Mercuur, 58: 103-104, 119-121. 1935.] (33) CALIFORNIA AGRICULTURAL EXPERIMENT S °23. Insecticidal value of derris. In Calif. A ;r, Expt, Sta. Ann, Bpt. 1922-23: 152. (34) (35) (36) (37) (33) (39) (40) (41) (42) (43) (44) CALIFORNIA FRUIT GEOEEPS' EECFA1TC-S, BUREAU OF PEST CONTROL 1935. Preliminary results of nev/ citrus sprays against black scale. Exch, Pest Control Cir, 11: 1-3, November. 36, So-called "non-oil" sprays. The use of Selocide in the Rivera-Dovrney-Whittier area. Exch. Pest Control Cir, 20: 2, 3. August, 1937. The scale control program for August. trol Cir. 32: 4„ August, Exch. Pest Con- 193. , Citricola scale. Exch. Pest Control Cir. 33: 3. September 1938 Importance of winter red scale treatment. Exch., Pest Control Cir. 38: 2-3. February. IS 38. Water rot again appears in oil-sprayed navel orachards. led spider. Exch. Pest Control Cir. 39: 5-6. March. 1938. Present spider condition. Exch. Pest Control Cir, 41, 4 pp. W y. 17<58, General insect conditions in Southern California, Exch, Pest Control Cir. 42, 4 pp. June. 1938. [Derris-oil] Exch. Pest Control Cir. 43: 4. July. 1938. Lov; dosage rotenone-cil products for red scale. Exch, Pest Control Cir. 47: 3-4. November, 1959, Treatment of black scale should be hastened. Exch. Pest Control Cir. 57: 1. September, (45) — -— 1939, Black and citricola scales, Exch. Pest Control. Cir, 58: 2. October. (46) 1939. Black and citricola scale in interior areas. Control Cir, 59, 4 pp, Eovem.be r. xch. Pest ..... ■^ - 97 - (4-7) CARLOS, A. S. 1926. Derris and its uses as an insecticide* Pert,, Feed. Stuffs and Farm Supplies Jour. 11: 161, (48) CASTILLO, I. 1326. Preliminary studies on the irsecticidal properties of three species of derris in the Philippines* Philip- pine Agr, 15: 257-275. (49) CHAMBSELIH, J. C. 1933. Results with rotenone dusts and sprays. U. S.Dept. Agr. Bur. Ent. Ecnthly Let. 234: 7. [Frocossed.] (50) COLORADO . ■ i STATIC 193G. [Potcnone and cube]. Colo. Hxpt. Sta. Ivan, Rpt. (1934-35) 48: 20. (51) coisPTorr, c. c. 1930. Greenhouse pests, a manual of practice in the control of insects and other pests att. ornamental plants and flowers green under glass in Illinois. Ill, Nat, hist. Survey Cir. 12, 112 pp., illus. (52) C0P3ETT, G. E. 1930. Entomological notes. Third Quart, 1330. Malayan Agr, Jour. 18 s 511-513. (53) Cr--, E. r . 5, Dustin: for the pea aphis. Jcur. Econ, Ent. 16: 81-S4. (54) 1938. Schedule lor the control of rose oests. 2 pp., illus, [Processed.] (55) _____ and 07L ; >HAE S C. 1936. Pea aphis control in Maryland. Peninsula Port. Sec. [Del.] Trans. 26: 2-1-26. (56) _„_-_.,- and I* T , ?. 1937, Observations on Brood X oT t] riodical cicada in L. J r. Seen. t. ' i : 287-294, (57) C?AUFOT_>BEI T SOF, R. J. 1958. The select,,.': a standard insect . ■ labor be ry testing c '"'cticides Bui. Ent. Res. 29 (2): 119-123. July. (58) CPOSBY, C. it., CEUPP, C., and LEI3Y, P. .. 1954. The control of diseases cts affecti: ble crops I i ■ ■, 11, Y, Agr. Col, . 11 ) :.: . Bui. 278, 11' pp., illus. (Rev. 1953.) - 93 - (59) CURRIE, J. H. 1934, Rotenone, a powerful new insecticide. Pacific Rural Press 128 (12): 215 (60) OUTRIGHT, C. R s 1950. Apple aphids ir. Ohio. Ohio Agr. Expt. Sta, Bui. 464, 59 pp., illus. (61) DAMKEHE ' \, K. v .\ 19-, In the agricultural zoology of the Malay Archipelago. 473 pp., illus. Amsterdam. [Derris, pp. 392-395.] (62) DARLEY, 1". a, 1931. Some irative tests with rotenone, nicotine, and pyre> thrum. Jour. Boon. Ent. 24: 111-115. (63) DAVIDSON, W. M. 1930. Rotenone as a contact insecticide. Jour. Econ, Int. 25: 868-874. (64) (65) (66) (67) 19 50. The relative value as contact insecticides of' some con- stituents of derris. Jour. Econ. Ent. 23: 877-879. and JONES, H. A. * 1931. Charge in toxicity of rotenone in solution and suspension. Jour. icon. Int. 24: 257-252. DAVIS, J. J. 1932. Derris. Insecticides and their uses. Purdue Univ. Pharm. * Ext, Ser. I, Bui. 32 (7): 27. DELI PROEFSTATIOI TE MEDAN 1926 „ Bereiding van akar-toeba extract. Doli Proefsta. tc Medan Meded. 42 (2): 25-23. (68) (69) 1927. Report of the Deli Experiment Station for January 1, 1926, to December 31, 1926, Deli Proefsta. te Kedan Meded, 45 (2), 36 pp. 1929, Akar toeba (Derris elliptica) het bestrijdingsmiddel van de tabaksluis [ Myzu s pers icae) in Deli. Deli Proefsta, te Medan Meded." 53" XzjT'z'-^ illus. (70) 1931. Verslag van het Doli Proef station over het Jaar 19 30. Deli Proefsta. te Medan Meded. 68 (2), 31 g . (71) 1933. Akar tooba. Verslag van het Deli Prcefstation over het Jaar 19 32. Deli Proefsta, te Medan Meded. 84 (2): 30-33, 48. - 99 - (72) DE LONG, D. M. 1928. Some observations upon the biology and control of the potato loafhcpper ( Erapoas ca f ab e.e Harris). Jovr. Soon. But, 21: 185-138. (75) DENNIS, W. J. 1927. Vermifuge and insecticide. U. S. Patent 1,621,240; issued March 15, 1927. (74) - 1952, Vermifuge and insecticide. U. S. Patent he. 18,667, issued November 22, 1932. (75) DF OFG, E. R. a.930. The comparative insecticidal value of different species of derris. Jour. Econ. Ent. 23: 619-624. (76) -- and 7v"HITE, L. T. W. 1924. Further studies of derris as ar. insecticide. Jo^r. Econ. Ent. 17: £99-501. (77) DESHPANDE, V, G. 1957. Cabbage aphid - S iphocoryne indobrass icae - and its control v.ith home-made nicotine spray, Agr. and Live- stock in India 7: 756-762. (78) DEUTSCHE!? PFMFZEFSCEUTZDIENST 1931. Pflanzenschutamittelverzeichnis des deutschen Pflanzen- schutzdienstes 19 31 Mittel gegen Pflanzetokrankheiten, Schadlinge. and Unkrauter. Deut. Pflanzcnschutzdienst Merkbl. 8 (4), 8 pp. (79) DIBBLE, C. B. 1938. Bug- house fables. Mich. Agr. Ext. Scrv. 8 pp. [Processed.] (80) DICKEY, E. D., and LCUCKS, K. W. 1938. Grape growing in Florida. Fla. Agr. Exp't. Sta. Bui. 324, 56 pp., illus. (81) DITnAN, L. P. 1959. Practical aspects of pea aphid contr 1. Peninsula Hort. Soc. [Del.] Brans. 28: 156-141. (82) — CORY, ". ]"., and GRAHAIT, C. 1939, Studies on pea aphid control. Jour. Been; Ent, 32: 537-546. (83) DCFGLASS, J. R., BMFLAhBD, C, and GILLBTB, J. A. 1059, Field oxporiments for control of t] ] or in Idaho, 1956-37. Jour. Econ. Fat. 32: 69-78. (84) DUDLEY, J. B. , Jr. 1935. Insecticide tests against pea aphid. U. S. Dcpt. Agr., Bur. Ent. and Plant Quar". Nows Let. 2 (2): 18. [Processed.] •100 - (85) — ~- - and SE03JS0N, T. E. 1333. Experiments against pea apbid in southern Wiscons'in< U. S 6 Dep+o Agr.j Bur, Put. and Plant Quar, Notts Lot. 5 (10): 20-21. [Processed.] (86) (37) (88) (89) (90)- (91) (92) (95) (94) (95) (96) — „-, ana 31'CNSOl , T, S. 1939 . I»ov; wind velocities at night favor dusting for pea aphid control, U. S, Dept, 1 r f , Bur. Ent, and Plant Quar. News Let. S (2): 16. [Processed.] BROHSON, T. E., and CARROLL, P. E. 1353, Experiments with d err is as a control for the pea aphid, U, S, Dept* Agr«, Bur. Hint, and Plant Quar. E-365, 11 ppi [Processed,] __„__.._ BRONSON, T. E.-, and CARROLL, P. E. 1936. Experiments with derris as a control for the pea aphid. Jour. Peon. Ent. 29: 501-508. __„_-„_ BBDKSON, T. P., and CARROLL, P. S. 1937. Summary of experiments with derris and cube against the pea aphid during the season of 1956. U. S. Pept. Agr, Bur. Put. and Plant Quar. E-400, 6 pp. [Processed.] DUELAP, A. A., and TTRHER, P T . 1938. Vegetable pest control schedule. Conn. (State) Agr. Expt. Sta. Cir*. 121: 2 7-49, illus. DURHAM, H. E. 1926. Non-arsenical preparations for garden use. Hard. Chron. [London] (3d Ser.) 79: 213-214.' EBHJNff, W. 1940. Toxicants and solids in oil used against the red scale. Calif. Citror. 25: 90, 130. PPPAPB3, W» D. 3. Sfrauberry pests, including spittle bug. Oreg. State Port. Soc. Proc. 50": 58-65. Nov. 14-16, 1935. ENGLISH, L. L. 193S. Derris as a toxic supplement to oil emulsions for the control of purple scale. Jour. Econ. Pnt. 32: 507-595. P-'j. , — — • 1851. The Island of Banka. Extract from "Schilderungen aus Ostindiens Archipel." Jour. Indian Archipelago and East. Asia 5: 269-291. EVANS, J. 17. 1938. The pear slug. Tas.manian Jour. Agr, 9: 130-131. ^-^.„. , . . ., . ., . .. ■■ i. . , | i , „_,^_. ■.-., , ... a - 101 (97) EYER, J. R. 1927. Tests of some recently developed insecticides in control of the grape leaf hopper and oriental fruit moth. Jour, Econ. Ent. 20: 253-231. (98) FARRAR, M. D. 1936. The effect of petroleum-oil sprays on insects and pla: 111. Nat. Hist. Survey Bui. 21, 32 pp., illus. (99) FEDERATED VJM.Y STATES DEPARTI"eLtT OF AGRICULTURE 1924, Malayan Agriculture Handbook. Fed. Malay States Dept. Agr. 301 pp., illus. Singapore. (100) FEDERATED TiuL-.Y STATES DEPARTIS1JT OF AGRICULTURE 1937. Fed. Malay States Dept. Agr. Res. Econ. and Agr. Ed. Brunches Rpts. 1936. (Gen. Ser. 26), 97 pp. (101) FEBTCN, A, 1956, The use of sulfur in the control of truck crop and cane fruit insects and diseases. 86 pp. Texas Gulf Sulfur C oiripan y, Hbu s t on , T e x . (102) FLORIDA AGRICULTURAL EXPERIJEFT STATIC! 1 1926. [Derriscl] Fla. Agr. Expt, Sta. Ann. Rpt. 1926: 43R. (103) 1931. [Derrisol] Fla. Agr. Expt. Sta. Ann. Rpt. 1930: 72. (104) - 1934. [The green citrus aphid] Fla, Agr, Expt. Sta. Ann, Rpt. 1933-34: 54. (105) 1937, [Bean jassid investigations] Fla. Agr. Expt, Sta. Ann. Rpt. 1936: 66, (106) FOOTS, V. r . A. 1931, Application of insecticides in S una t ran tobacco fields. U, S, Bur. Foreign and Dom. Cora., World Trade States on Chemicals and Allied Products 5 (8): 4-5. (107) FRYER, J. C t F, , STENTOH, R,, TATT EPS FIELD, F., and ROACH, W, A. 1925, A quantitative study of the insecticidal properties of Derris elliptica (tuba root). Ann. Appl, Biol, 10: 18-34, illus. (108) FRYER, F. J. 1926, Derris as an aphis spray. Fla. trover 33 (14): 20, (109) FULMEK, L. 1924, lets over de toepassing van bestrijdingsmiddelen bij delitabak. Deli Proefsta, te Medan Vlugschr. 29: 1-4. - 102 - (no) (111) 1924, Bestrijding van bladluizen. Deli Proefsta. te Me dan Vlugachr. 30: 1-4. 1925, Techniek der bladluizenbestrijding net akar toeba. Deli Proefsta, te Medan Vlugschr. 35: 1-4, illus. (112) 1927 # Uber die situation der schadlingsbekarnpfung in den tabaldculturen auf Sumatra, Dent. Gesell, f. Angew. Eat. Verhandl. (1926) 6: 49-55. (113) FULMER, H. L. 1950, Insecticides, fungicides, and herbicides. Ontario Dept. Agr. 11, 351, 75 pp. [Abstract in Malayan Agr, Jour. 18: 462.] (114) GAINES, Ri C, 1939, Effects of some insecticides on cotton leaf aphids, U, S, Dept, Agr., Bur. Eat, and Plant Quar, News Let. 6 (11): 17, [p r ocrssca. (115) GAM3RELL, F. L. 1931, The spruce gall aphid (Adelge s ablet is ) as a nursery pest. Jour. "con. Ent, 24: 355-361, (116) G&EU&Nj P. 1928, Tests -with insecticides designed to do the v/ork of nicotine sulfate. Conn. (State) Agr. Expt. Sta, Bui. 294: 277-278. .(Conn. (State) Ent. Rpt. 27, 1927.) (117) (no) 1934. Study of aphicides. Conn. (State) Agr, Expt. Sta, Bui, 360: 458-431. (Conn. (State) Ent. Rpt. 33.) 1936, Continued tests with substitutes for lead arsenate. Conn. (State) Agr. Expt. Sta. Bui, 383: 324. (Conn, (State) Ent. Rpt. 35/ 1935.) (119) GDHNGHAM, C. T. 1934, Recant researches on insecticides in Great Britain. Pacific Sci. Cong. (Canada) Proc. (1933) 5: 3423-3437. (120) GEZLETTE, J. D. 1323. Ualay Poisons and Charm Cures. Ed. 2, 260 pp., illus. London. (121) GIHSftRvG, J. M. 1933. Rotenono. Its ir.secticidal value. N. J. Agr. Expt. Sta. Cir. 273, 2 pp. - 103 - (122) -..-.—..- and CFAKJ3TT, P. 1934, Derrir, insecticides. II, Inseerticidal properties of ©attracted derris root residue. N. J, Agr. Sxpt. Sta. Dul. 576: 16-23. (123) and GPA1TETT, P. 1054. Insecticidal properties of completely extracted derris root residue. Jour. Scon. Bit, 2' 7 : 393. (124) — — — and GPAFETT, p. 1935, Derris insecticides. III. Aphicidal properties of derris and cube root. F. J. Xi.gr* Exot, Sta, Bui, 581, 12 pp. (125) — and SCJ3JITT, J. B. 1932, A eoivroarisor. between rotenone and pyrethrins as contact insecticides. Jour. Scon, Hit, 25: 918-922, (126) SCHMITT, J. B., and GR&HETT, P. 1934, Derris insecticides. I, Toxicity of various extracts of derris root to sucking and cl ; .o'..i. v \ insects. K, J, Agr, Expt. Sta. Bui. 576: 3-16, (127) SCKMITT, J. B., and GBAiETf, P. 1934. Toxicity of various extracts of derrif; root to sucking and chewing insects. Jour. Econ, Ent. 27: 446. (128) GMDINC-ER, C. 3. 1933. Pyrethrum flowers, 269 no,, illus, 7.;inneapoli: : , (2d ed., 1936.) (129) GOFF, C. C, and TISSOT, A, IT, 1932, The melon aphid, Aphis gossypii Glov-r. Fir.. Agr, ~'xpt, Sta. Bui." 252: 23. (130) GRAFAL, C. 1937. Pea aphid control in Llarvland. Jour. Econ, Ent. 30: 439-443. (131) — - 1939, Pea aphid investigation in Maryland. Peninsula Hort, S c. [Del.l Trars. 29: 29-34-'. (132) and COPY, E. 1 . 1959. Field tests or cortrcl of the pea aphid, Illinoia pisi (Kith.) Jour. Eccn. Ent. Z2i 574-57G, (135) GRAtfETT, P. 1935. Derris insecticides, IV, Further studies on the insec- tioidal properties of derris root residues extracted with different solvents, N, ■' . ugr, Expt. Sta, 3ul. 583, 12 pp. - -104 - (134) (135) (136) GUHDEPSOH, H. 1S38. Controlling garden insects in Iowa. Iowa State Col. Ext. Serv. I.C-161, 22 pp # [Processed.] HAMILTON, C. C. 1933. Rotenone, pyrethrins, and nicotine as sprays. Shade Tree 6(1): 2-5. 1938. Tests with derris powder or cy.be powder in rosin residue emulsion sprays for the control of shade tree insects. Fati. Shade Tree Conf. Proc. 13: 140-147. 1937. (137) and GEffiELL, L. 1934. Sone field tests showing the comparative efficiency of derris, pyrethrum, and hellebore powders on different insects. Jour. Econ. Ent. 27: 443-453. (138) (139) (140) (141) (M2) HMER, 0. H. 1938. The scurfy scale- and its control. Jour. Econ. Ent. 31: 24< -249. HALiPP, H., and JEKL, J. 1938. Erdfloh-Bekampfungsversuche bei Hopfert auf dem Hopfen- versuchsgut in Hull 1937. Hachrichtchbl. f, den Deut, Pflanzenschutzdienst, 18: 42. ■ Hay. [Abs. in Pev. Appl. Ent. (A) 26: 522.] HANSON, A. J., and WEBSTER, R. L. 1935. Insects of the blackberry, ■ raspberry, strawberry, currant, and gooseberry. Yfesh. Agr. Expt, Sta. Pop. Eul. 155, 38 pp., illus. hapfisou, P. K. 193G. Dust mixtures containing rotenono control turnip aphid. U. S. Dept. Agr., Bur. Ent. and Plant Quar. Hews Let. 3 (9): 21-22. [Processed.] (143) (144) 1939. Efficiency of rotcnone-dust mixture against turnip aphid rot improved by conditioning agents. U. S. Dept Agr. Bur. Eat. and Plant Cuar. Hews Let. 6 (10): 20. ["Processed.] FAPTZELL, F. J. 1950. Toxicity of sprays and spray ingredients on pear psylla nymphs. Jour. Econ. Ent. 23: 190-197. HAUDE, ?;. J. 1939. Outline of uses and recommendations for rotenone dusts and sprays. John Powell £ Co., Now York, IT. Y. , 20 pp. [Processed.] - 105 - (145) HEADLEE, T. J. 1926. Report cf the department cf entomology. N. J. Agr« Expt, Sta. Ann. Rpt. 46, 507 pp. (146) HENDBEN, P. P. 1931, Cultivation of Derri s ellip tica (tuba root) in "ether- lands India. 5. S.~ Dept, Com, Spec. P.pt. 25, IB pp. [irocessed. ] Batavia, Java# (147) EEB&lB, F. A., and HOCKEY, J. F. 193S. Control of potato flea beetle, Epitrix o ucumeris Harr. Jour. Econ. Ent. 29: 1173~ll r; 4" (148) HOLLRUKG, H. 1923. Die lfittel zur Bek&apfung der Pflar.zer.krankheiten. 405 pp. Berlin. (149) KOYaED, N. F. 193S. Dusting sulfur and sulfur-pyretlirun? dust mixture give best results against potato leafhopper on beans. U. S. Dept. Agr., Bur. Ent. and plant Cuar. JTevs Lot. 5 (10): 21- [Processed.] (150) 1939. Sulfur and sulfur-pyrethrum dusts most effective against potato loafhopper on beans, IT. S. Dept. Agr., Bur. Ent. and Plant Quar. 1\ t ct;s Let. 6 (2): 17. [Processed.] (151) 1939. Dusting sulfur and sulfur-pyrcthrum dust mixture give bust results against potato loafhopper on bcaus. Ext. Ent. 5 (i): 14. Varch. (152) 1940. Nicotine dust superior to rotcnono dusts for cabbage aphid control. U. S. Dept. Agr., Bur. Ent. arc 1 - Plant Quar. News Let. 7 (8): 2G. [Processed.] (153) „ and IIASON, II. C. 193 7 . Results of experimental i/orh rath rotenone-bearing materials for the control of vegetable insects. Ohio Veg. Grovrers' Assoc. Proc. 22: 19-25. (154) TL-SCIV, h. C, and DAVIDSON, P.. H. 1935. Derris for the control of certain vegetable ir.sects. Ohio Veg. Growers' Assoc. Free* 20: 21-25. (155) -— and NELSON, E. H. 1939. Kico tine-hydra ted lime dust mixture more effective against cabbage aphid than dust mixtures containing rctenone ulth various conditioners. U. S. D« ?t. Agr,, Bur. Ent. and Plant C.uar. ITov/s Let. 3 (9): 26. [Processed. 1 (156) (157) (158) (159) (160) (161) H0"RES, F. N. 1937. Tephrcsia iaaeropoda as a possible insocticidal plant. Kent Roy/' 3ot. Gard. Bui. Ilisc. Inform. 10: 510-513. EUCXETT, H. C, and HEWEY, 'G. E. R. 1935. Recent developments in the use of arsenical substitutes for vegetable post control in How York. Jour. Econ, Ent. 28: 602-603.' HUTS ON, R. 1934. Observations on the habits and control of Glossonotus crataegi (Yicrhracidae), on plum and apples. Jour. Econ. "Ent. 27: 365-367. IDAHO AGRICULTURAL EXPERIMENT STATION 1933. [Cubor] "Work and progress of the Agricultural Experiment Station for 1932. Idaho Agr. Expt. Sta. Bui. 197: 38. 1936. [Cube-Kaolin Dust] Science aids Idaho farmers. Idaho Agr. Expt. Sta. (Ann. Rpt. 1935) Sul . 220: 31. 1937. [Derris] Idaho Agr. Expt. Sta. (Ann. Rpt. 1936) 3ul. 221: 32. (162) INSTITUTE OF PHYSICAL ■-1TD CHEIIICAL RESEARCH 1927. "Neoton" r/hat it means to agriculturists. Inst. phys. and Chem. Res., Japan., 12 pp. (163) ISHIGAI, K. 1937. Booklet on "Derris." [in Japanese.] [Submitted with letter dated "a y 17, 19 37, from C. C. Concannon, U. S. Bur. Foreign and Dom. Com.] (164) JONES, H. A., and DAVIDSON, W. Y. 1931. Preparations containing rotenone for use as insecticides I. Aqueous suspensions. Jour. Econ. Ent. 24: 244-257. (165) — —- .- and STIITH, C. K. 1936. Derris and cube. Soap 12 (6): 113-117. (166) JONES, 11. P. 1939. 4-H Club insect manual. U. S. Dept. Agr. Ilisc. Pub. 318, 63 pp., illus. (167) KEAR1S., H. G. H., and HARSH, R. W. 1937. A summary of fruit spraying programmes. I. Bristol [England] Univ. Agr. and Hort. Res. Sta. Ann. Rpt. 1936: 75-89. ms^am mm - 107 - (168) MARSH, R. W., and PEARCE, T. J. P.. 1932. Experiments with combined insecticide-fungicide sprays for apples. Progress Rpt. L'ristol [England] Univ. Agr. and Reft, Res. Sta. Ann. Rpt. 1932: 63-85. (169) KELS.iL, A., SPIT TALL, J. P., GORHAM, R. P., and VLVLKSR, G. P. 1926. Derris as an insecticide. Ontario Ent. Soc. Ann. Rpt. (1925) 56: 24-40 (170) and STU1TZ, H. T. 1937, Pyre "thrum and derris dust. Ontario Ent. Sec, Ann. Rpt. (1936) 67: 20-30. (171) KENTUCKY AGPJCIJLTURAL EXPSRIHEFT STATI02! 1934. [Rctenone] Ky. Agr. Expt. Sta. ^rra. Rpt.- (1933) 46 (Part I): 42. (172) OOWLTONi G. F. , SMITH, C. F. , and UAFJ'STOH, F. C. ■ 1938, Pea aphid investigations. Utah Acad', Sci. Arts and Letters Proc. 15: 71-60. (173) and SORB27SON, C. J. 1937, The pea aphid. Utah Agr. Expt. Sta. Leaflet 76, 4 pp. (174)X0L0NLAAL IUSTITUUT TE AMSTERDAM 1936. Insecticides of derris type. Chem. and Drug. 125: 244-245. (175) -— — 1936. Plantenziekten en -Flagon. Inlichtingen en onderzoe- kingen van de afdeeling haVidelsmuseum in 19 35. Amsterdam Kolon. Inst. Ai'd. Handel snuseum. Keded. 39 (16): 78-102, illu.s. . ( See ajlso Amsterdam. Kolonial lnstituut.) (176) KOPP, A. 1924. Les derris insecticides. Hev. de Bot. Appl. et d 'Agr. Colon. '3ul. 4 (34): 400-402. (177) LAAN, P. A. van der 1935. Bcrichten van de afdeeling Handel smi'-seum van de kon. ver. "Koloniaal lnstituut." No. 96, 15 pp. Over de houdbaarheid van de figtigheid van dorri : s'p6eder en rotenon. Indischc Mercuur 58 (IS): 257-259. r Also in Tijdschr. Plantenziekten. 41 (4): 77-87. 1935.] (178) 1956, Verslag ven do Negen-en-Zestigste "Wintorvorgadering dor Kcderlandsche Entomologischo Verecniging, ^jristerdam, February 23, 1936. 7ijdsc.hr. v. Ent, 79: 52-58. (179) LA DUE, J. P. 1938. Higher ketones as intermediary solvents for derris resinatc used in petroleum spray oil. Jour. Eccn. Ent. 31: 319-320. - 108 - (180) (181) (182) (183) (184) (185) (186) (187) (188) LENFESff, R. E. 1926. Citrus comments. Citrus Indus. 7 (4): 20. LEVER, R. J. A. Wo 1935. Local derris root as a possible export for insecticidal use. Brit. Solomon Isl. Agr. Com,, Agr. Gaz. 3t 5-6. LITTLE, V. A. 1931. Devil's shoestring as an insecticide. Science 73: 315- 316. 1931, A preliminary report on the insecticidal properties of devil's shoestring, Cracca virginiana Linn. Jour. Econ. Ent. 24: 743-754. LOUISIANA AGRICULTURAL EXPERIjIEIIT STATION 1937. Bug News 1 (4): 1-2. December 1. -. McBRIDE, 0. c. 1926. A leafhopper (Eupteryx flavoscuta var. nigra Osb.) attacking the leather-leaf fern (Polystichum capense J. Sm. ). Fla. State Hcrt. Soc. Proc. 39: 224-227. McDAMEL, E. I. 1928. Leafhoppers and aphids easily controlled, T/Iich. Agr, Expt/sta. Quart. Bui. 10: 171-172. 1934. The principal insect pests of juniper in Michigan. Mich. Agr. Expt. Sta. Quart. Bui. 16: 244-246. 'IcINDOQ, N. E. , and SIEVERS, A. F. 1924. Plants tested for or reported to possess insecticidal properties. U. S. Dept. Agr. Bui. 1201, 61 pp. _____ SIEVERS", A. P., and ABBOTT, W. So 1919. Derris as an insecticide. Jour. Agr. Res. 17: 177-200. (189) (190) MAINE AGRICULTURAL ESPEREiENT STATION 1937. Maine Agr. Expt. Sta. Prog. Rpt. 1937. Bui, 387, 262 pp., illus. (191) LiANBCBKE, R. 1937. Schadli'gsbelcampfung mit vrasserigen Derrispulver-Losungei Obst. u. Gemusebau. 83: 54. April 15. (192) MARTIN, J. T. 1936. Occurrence of rotcnone in Tephrosia macroppda Harv. Nature [London] 137 (3478): 1075. \ (193) MASSACHUSETTS AGRICULTURAL EXPEPJD'ENT STATION 1936. Department of entomology. Mass. Agr. Expt. Sta. Eul . 327: 40-42, 46, 47. -_?,/ - 109 - (194) 1957. [Derris] llass. Agr. Expt, Sta. Bui . 339: 3-3-40, 46-61. (195) __„ 1938. Annual Report (1937). Maes. Agr. Expt. Sta. Bui. 347, 99/pp. • (196) IEEE JIOEE, J. C. van der 1927, Eenigen v:enken voor de bestrljding van de bladluizenplaag (Jlysus persicae) in de deli-tabak. Deli Proof s : : . te FecTan Vlugschr. 42, 7 op., illus.. [Abs. in Rev. Appl. Ent. (A) 16: 165. (197) P;ERIM>, ff., and OTAFES, F. Q. 1938. Control of insects and other pests. Philippine Jour. Agr. 8 (4): 437-461, illus." (198) rETCALF, C. L., and FLINT, W.P. ; ,1928. Destructive and useful insects: Their habits and control. 918 pp r ' New York. (2nd ed. 1939.) (199) MICHIGAN AGRICULTURAL EXPERE'-SaT STATICS'. 1925. [Derris! ? 'ich. Agr. Sept. Sta, Ann. Ept, 1925: 222. (200) 1IILSS, K. if., and PILES, P. 1935. Insect pests of glasshouse crops. 174 pp. Surbiton, England. (201) KILLER, N. C. E. 1935. The toxic value of Derris spp. Fed. Kalay States Dept. Agr. [Bul.l Sci. Ser. 16, 44 pp., illus. (202) FILLER, E. L. . 1929. A contribution to the biology and control of the green citrus aphid, Aphis spiraecola patch, Fla. i gr, Expt . S ta . Bui. 203, "476" Pp. (203) PYSOPS [INDIA] DEF:.RTPEj t T OF AGRICULTURE 1938. Annual report of the department of agriculture, 1936-37, 203 pp. (204) KEISTftHDER, C. P. 1955.. Experiments in the control of two greenhouse mealybugs, Phenaooccus gossypii T. r CPU., and Pseudococcu s citri Risso . Jour . Eg or: . Bnt . 28: 4 05-410 . (205) NETTLES, W. C. . j 1959. Insect pests of South Carolina. Ft. 5. Garden and truck crop insects. Clemson Agr. Col. S. C. Pxt. Serv. Bui. 102, 32 pp., illus.' (206) m SE -. IC LTUEAL EXPERIMENT STi [< 1955. [Derris and cube] N. J. Agr. Expt. Sta. Ann, Rpt. (1935) 56: 43-46. 110 - (207) (208) (209) (210) (211) 1937. [Derris] IT, J, Agr., Expt. Sta. Ann. Rpt. (1936) 57: 41, 51-52. NEW MEXICO AGRICULTURAL EXPERIMENT STATION 1934. [Rotenone] ¥., Mex. Agr. Exp.t, Sta, Ann. Rpt. (1932-53) 44: 42. NEW SOUTH WALES EI r .0M0L0GICAL BRANCH 1936. The cabbage moth (Plutella maculipennis) . Agr. Gaz. N. S. Wales 47: 140-1417 NEW YORK AGRICULTURAL EXPERIMENT STATION 1937. [Rotenone] IT. Y. (Cornell) Agr. Expt. Sta. Ann. Rpt. (193C) 49: 41, 103-104. NEW YORK STATE AGRICULTURAL EXPERIMENT STATION 1928. [Derrisol] N. Y. State Agr. Expt. Sta. /inn. Rpt. 47: 44-46. (212) (213) 1936. Division of Entomology. "I. Y. State Agr. Expt. Sta, Ann. Rpt. (1935) 54: 54, 59-61. 1937. [Derris, cube] N. Y. State Agr. (1936) 55: 54-55, 5C-60. 3xpt, Sta. Ann. Rpt, (214) (215) (216) (217) (218) (219) 1938. Division of Entomology. N. Y. State Agr. Expt. Sta. Ann. Rpt. (193?) 56: 44, 45, 47, 49-50. OCFSMIA, G. 0. 1931. The bunchy-top of abaca and its control. Philippine Agr. 20": 328-340. OHIO AGRICULTURAL EXPERIMENT STATION 1922. [Derrisene] Ohio Agr. Expt. Sta. Ann. Rpt. (1922) 41 : xxxi . OREGON AGRICULTURAL EXPERIMENT, STATION 1937. Effect of agricultural and home economics research on Oregon's agricultural progress. Oreg. Agr. Expt. Sta. Bui. 350, 85 pp., illus. OtERLEY, F. L., and OYERHOLSER, E. L. 1932, Some factors influencing spray injury on apples. Tvash, State Hort. J.ssoc. Proc.~27 (1931): 23-30. PARKS, T. H. , and PIEESTORFF, A, L. 1938. The control of garden insects and diseases. Ohio Agr. Ccl. Ext. 3ul. 76, 56 pp., illus. - Ill - (220) RftBROTT, P. J., and GLASGOW, H. 1930. The rosy aphid in relation to spray practices in 1929. B. Y. State Agr. Expt. Sta. Bul» 582, 32 ryp., ill us. (221) PATTEBSON, IT. A. 1936. Mealybug control in Nova Scotia, Ontario Bht. Soc. Ann, Ppt. (1935) 66: 34-36. (222) PEA APHID CONPEBEBCE 1936. Suggestions for the control of tile pea aphid in 1S38, 2 pp. [Processed,] Summary of remarks at the Pea Aphid Conference, 12 pp. "Processed.] Indianapolis, Ind., Dec, 27-28, 1937. Prepared by a committee of entomologists representing a number of State experi- ment stations and the Bureau of Entomology and Plant Quarantine, U. S. Dept. of Agr* Distributed ~'jy the IT* S. Dept. Agr., Bur, Ent. and' plant r uar. Fob. 28, 1938. (223) PETTI CK, S. 3., and CCI'PAITY 1933. Derris, the new safe insecticide. 3.4 pp.. illus. New York. [4th ed., 1936.1 (224) PSPFEP, B. B. 1937. Fink and green aphids and their control. Canner 84 (5): 54, 57-58. Ser. r?o. 2189. (225) — and BAEB3ELEP, C. ?:. 1939. Pyrethrum and derris as a control for the six-spotted leaf hopper, a vector of lettuce yellows. Jour. Econ. Eat. 52: 2 91-296. (226) PETHS:"3 r IDGE s F. P., and WRIGHT, D..¥. 1958. The cabbage anhis (Breviccryne byassicae L. ). r Gt. Brit, Min. Agr. and Fisheries Jour". 45: 140-148. (227) PBYEI, W. 1230. Eine neue insektizid wirkende Droge: Derris elllpti ea. Chem. Ztg. 54: 724. ' (226) E&IBWttTBR, C. F. "1938. Tests against cotton root aphids. U. S. Dept. Agr., Bur. Ent, and Plant Quar. Mews Lot. 5 (6): 15. (229) RED5CK53 , S. 3. 1926. Sumatra as a soufce of supply for derris or tuba root. U. S. Bur. Foreign and Den. Con. Spec, Cir. 144, 3 pp. r - i ^Processed. (230) KHOADS, A. 8., and DEBUSK, E. ?. 1951. Diseases of citrus in Florida. Fla. Agr. ?fccpt. Sta, Bui. 229, 213 pp. - 112 - • (£31) RICHARDSON, C. H. . >• 1928. Insecticide studies develop many new "ways to kill pests. U. S. Dc.pt. Agr. Yearbook 1927: 389-393. (232) RICHARDSON, H. K. 1935. A progress report en the insecticidal control of the Mexican mealybug ( Phenao ocous gossypii T. ■■■ Clcll.) on greenhouse chrysanthemums. Jour. Econ. Ent. 28: 29 9-405. (233) RIVNAY, E. 1959. Studies in the biology and control of Pseudococcus com- stocki Ktrwana on citrus in Palestine. Radar 12: 197- 20l~ July. (234) ROARK, R. C. 1938. Derris versus cube - Is cube equal to derris as an in- secticide? Soap 14 (1): 111-113, 120. (235) ROCKYifOOD, L. P., and GEMBERLIN, T. R. 1934. Pea aphid on vetch and Austrian winter field peas in Willamette Valley. TJ. S. Dept. Agr., Bur. Ent. Monthly Let. 240: 13. [Processed.] (236) ROC-EPS, W. S., KING, M. E. , and MASSES, A. M. 1939. Results of researches in strawberry growing. Sci. Hort. [%e, Kent] (1939) 7: 71-84. (237) ROTEAMSTED EXPERIMENTAL STATIC?: 1924. Insecticides. Rotham.sted Expt. Sta., Harpenden, Rpt. 1923-24: 35. (238) RUBBER SERVICE LABORATORIES COMPANY, IRC. 1935. The use of Areskap and Arc sleet in insecticidal sprays. Rubber Service Laboratories Company, Inc., GLIi 634, 5 pp. [Processed.] (239) SCHSER, J. van der 1935. Over emulsies van het . insecticide rotenon in -water. • Bergcultures 9: 358-361. (240) SCB8LITT, H. 1930. Derris elli ptic a Benth., cin vcgetabilischer und 'ungif- tieer insecticidlieferant. AngeiS". Bot. 12: 453-463. (241) SHEPARD, H. H. 1931. The relative toxicity of ro tenon e and nicotine to Aphi s rumicis L* and mosquito larvae. Jour. Econ. Ent. 24: 725-731 . (242) SR4A°TAS0N, J. B. 1938. Some comparisons of dusts for potato leaf hopper control on Long Island, Amer. Potato Jour. 15: 271-277. - 113 - (243) SLEESJIAI*, J. P. 1057. The potato leafhopper. Ohio Veg. Growers 1 Assoc. Proc. Attn, Yeet. 22: 69-75. (24-I) SMITE, C. L. 1937. Studies on the use of derris powder in the fom of an aqueous suspension. Canner 84 (5): 36, 38, 40. Ser. ho. 2189. (245) SHITEy L. 0. 1940. Spittle bug. Bugs -- Nevrs about TVashiiagton insects. June 5, 1940: 11. (TDash. State Col. Ext. Serv.) [Processed! (246) SUITE, h. K. 1929. Experiments 'with toxic substances in spray oils in con- trolling red scale, Calif. Citrog. 14: 315, 326, (247) — 1932. Experiments with toxic substances in highly-refined spray ■ oils. Jour, Eccn. Ent. 25: 9S8-990. (248) — 1938. Microtechnique method of testing oil insecticides on scale insects. Jour. Scon. Ent. 51: 632-633. (249) SOUTH CAEOLIEA AGIIChLTTUAL EXFEhCEhT STATION 1937, Tests in the control of the cotton root aphid. S. C. Agr. Expt. Sta. Ann. Rpt. (1937) 50: 101-102. (250) SPOOK, I. W. 1533. Eet insecticide rotenor? in de riederlandschc praktijh, cerste proef jaar. Amsterdam Kolon. Inst, Afd. Handels- museum Ber. 83, 17 pp., illus. Indische ' 'orcuur 56 (51): 005-607. . (251) STEA5HS, L. A. 1938. Comments on ■'die control of several frvi and vegetable insects. Peninsula Eort. Soc. [Del,] Trans. 1957: 120-125. [Abs. in -lev. Appl. Ent. (A) 26: 443-444.] (252) — — — EftDEH, TT, It., and WILLIAMS, L. I. 1956, Grape leafhopper and grapeberry moth investigations. Dei. A ;r. Expt. Sta. Bui, 198, 44 pp., illus. ^ C O O J Oi J.ijj . , Iff , 1936. Insecticides and fungicides. The use of derric root as an insecticide. East Hall i [Kent] Hes. £' .. Ann. P.pt. 1935: 225-227. (254) SUFF0IX COUNTY [E. Y. i FAE! BuTd2AU 1933. Eev; insecticides for bean beetles, Sv 1] County Farr. Bur; Re-'S 17 (7): 9. \ - - 114 - (255) SYIiES, C. B. 1924. Notes on the blaclc citrus aphis. Rhodesia Agr. Jour. 21: 612-626, 725-737. (256) TATTERSFIELD, F. 1925. Fish poisons as insecticides. Nature [London] 116: 243. (257) 1927. The relationship betvreen the chemical constitution of organic compounds and their toxicity to insects. Jour. Agr. Sci. [England] 17: 181-208. (258) 1932. Laboratory methods for evaluating insecticides. Ann. Appl. Biol. 19: 281-290. (259) and GETINGHAII, C. T. 1927. Recent investigations or contact insecticides. Soc. Chem. Indus. Jour. 46: 368T-372T. (260) and GIUINGHAII, C. T. 1932. The insecticidal properties of Tephrosja mac rcpoda Earv. and other tropical plants. Ann. Appl. Biol. 19: 253-262. (261) GIIIINGHAII, C. T. , and T.TORRIS, H. :.*. 1925. Studies on contact insecticides. II. A quantitative examination of the toxicity of Tep h. ro sia vogelii Hook, to Aphis rumicis L. (the bean aphid.") Ann. Appl. BiolTT2~: 66-76.' (262) GIIIINGHAT.I, C. T., and "ORRIS, H. ". 1926. Studies on contact insecticides. IV. A quantitative examination of the toxicity of certain plants and plant products to Aphis rumicis L. (the bean aphid). Ann, Appl. Biol. IZt 424-445. (263) -— — and KARIIN, J. T. 1938. The problem of the evaluation of rotenone-containing plants. IV. The toxicity to Aphis rumicis of certain products isolated from derris root. Ann. Appl. Biol. 25: 411-429. (264) — — — and ROACH, W. A. 1923. The chemical properties of Derris elliptioa (tuba root). Ann. Appl. Biol. 10: 1-17. (265) TEXAS AGRICULTURAL ESPERII.1E1JT STATION 1936. Entomology. Tex. Agr. Expt. Sta. Ann. Apt. (1935) 48: 42-53. ■' (266) 1937. Entomology. Tex. Agr. Expt. Sta. Aim, Rpt. (1936) 49: 45-56. - 116 - (267) Thompson, v:. L. . 1950, Reduced cost in the control of aphids, Fla. State Hort, Soc. Proc. 1930: 106-114, (268) TIBUPvEO and BLATTNY 1939. Kratke zpravy. [Short Notes.] Ochrana Rostlin 15:51-56, illus. (With summaries in German.) [Aba. in Rev. Appl. Ent. (A) 27: 4-70-471; Cher.. Ads'. 34: 6004.1 (269) TISSOT, A. P., and THOMPSON, W. L. 1950. Per; aphic ides. Fla. Ent. 14 (l): 7-12. (270) TRAPPPANN, W., and NITSCHE, G. 1.35. Beitrage zur Giftvlrkung von PcTor.cn una Pyrethrii auf verschiedene InscPten. Nachrichtenbl. f. den Deut. Fflanzenschutzdienst 15 (l): 6-7. (271) 'I ] . -i„ 1952. Notes on rotenoneas an insecticide. Jour. Soon. Ent. 25: 1228-1257. (272) — 1935. Tests on the control of certain vegetable insects. Conn. (Stat.) Agr. E::pt. Sta. Bui. 368: 245-247. (State Ent. Rpt. 34) (273) 1957. Control of leafhoppcrs on dahlias. Conn. State Ent. Rpt. 36: 570-371*. (274) UNITED STATES DEPARTMENT OF .1GPICPL7UP7 193G. [Derris and cube] Report of the Secretary of Agriculture 1936: 69. (275) — 3UPEAF OF ENTOMOLOGY 1919. [Derris] Report of the entomologist. !;. 5. Dept. Agr., Bur. Ent. Ann. Rpt. 1919: G. (276) r BUREAU OP ENTOMOLOGY 1930. Codling Moth Conference, 1950. U. S. Dept. Agr., Bur. Ent., S3 pp. Tfeshington, D. C. [Processe .] (277) 3UPEAU 07 ENTOMOLOGY AND PL iTTNE 1935. ; , partial report of the sectio: . Association of Economic Sntomolo gists jk'eetii in Pittsburgh, Pa., on Dec. 77, 193