SB 945 U. S. DEPARTMENT OF AGRICULTURE, BDREAH OF ENTOMOLOGY BULLETIN No. 87. L. O. HOWARD. EnlomoloeisI and Chief o( Buieau. REPORT ON THE FIELD WORK AGAINST THE GIPSY MOTH AND THE BROAVN-TAIL MOTH. D. M. ROGERS, Special Field Agent, AND A. F. BURGESS, Expert in Charge of Breeding Experiments. Issued August 13, 1910. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1910. Qass ^B 3 4 5 Book . G 3 1? 7 Bui. 87, Bureau of Entomology, U. S. Dept. of Agriculture. Plate I. The Gipsy Moth (Porthetria dispar). Fig. 1.— Male moth. Fig. 2.— Ftmale moth. Fig. 3.— Male pupa. Fig. 4.— Female pupa. Fig. 5.- Egg cluster. Fig. 6.— Caterpillars; the largest are less than half grown. (Original.) ^ U. S. DEPARTMENT OF AGRICULTURE, I' BUREAU OF ENTOMOLOGY -BULLETIN No. 87. L. O. HOWARD. Entomologist and Chief ot Bureau. REPORT ON THE FIELD WORK AGAINST THE GIPSY MOTH AND THE BROWN-TAIL MOTH. a ^ dAm./rogers, Special Field Agent, A. F. BURGESS, Expert in Change of Breeding Experiments. Issued August 13, 1910. WASHINGTON: GOVERNMENT PRINTING OFFICE, 1910. ^^jV 4 \ \ \ ^A '^''^"^ B UREA U OF ENTOMOLOGY. L. O. Howard, Entomologist and Chief of Bureau. C. L. Marlatt, Assistant Entomologist and Acting Chief in Absence of Chief. R. S. Clifton, Executive Assistant. W. F. Tastet, Chief Clerk. F. H. Chittenden, in charge of truck crop and stored product insect investigations. A. D. Hopkins, in charge of forest insect investigations. W. D. Hunter, in charge of southern field crop insect investigations. F. M. Webster, in charge of cereal and forage insect investigations. A. L. Quaintance, in charge of deciduous fruit insect investigations. E. F. Phillips, in charge of bee culture. D. M. RoGE-RS, in charge of preventing spread of moths, Jield work. RoLLA P. CvRRiE, in charge of editorial work. Mabel Colcord, librarian. Preventing Spread of Moths. parasite laboratory. W. F. FisKE, in charge; A. F. Burgess, H. S. Smith, W. R. Thompson, C. W. Col- lins, P. H. Timberlake, R. Wooldridge, assistants. field work. D. M. Rogers, in charge; H. B. Dalton, Thomas W. Bowmar, H. W. Vinton, D. G. Murphy, I. L. Bailey, H. L. McIntyre, assistants. 2 AUG S6 laiu to LETTER OF TRANSMITTAL. U. S. Department of Agriculture, Bureau of Entomology, Washington, D. C, Aprils, 1910. Sir: The only accounts so far published by the Department of the large-scale work which is being carried on under congressional appropriations in the effort to limit the farther spread of the gipsy moth and the brown-tail moth in New England have been brief statements in the annual reports of the Chief of the Bureau of Ento- mology. The work has now reached such a stage that a comprehen- sive account of the work accomplished, the methods of work, and present conditions, is demanded. I therefore have the honor to submit for publication the accomi^anying manuscript, which includes a report on the field work for preventing the spread of the gipsy moth and the brown-tail moth, and which has been prepared l)y Messrs. D. M. Rogers and A. F. Burgess, of this Bureau. This report does not include a consideration of the efforts made to import and accli- matize the European and Japanese parasites of the gipsy moth and the brown-tail moth. That matter will be described in another bulletin. I recommend that the accompanying manuscript be pub- lished as Bulletin No. 87 of this Bureau. . Respectfully, L. O. Howard, Entomologist and Chief of Bureau. Hon. James Wilson, Secretary of Agriculture. 3 CONTENTS. Page. Introduction 9 Importance of the gipsy moth as an insect pest in this country 9 State work against the gipsy moth in Massachusetts, 1890-1900 11 Record of the gipsy moth in its native home 11 Life history of the gipsy moth 12 The eggs 12 The larvEe 13 The pupa? 15 The adults '. 16 Methods employed in work against the gipsy moth 16 Scouting 16 Spraying 17 Burlapping 17 Sticky bands 18 Cutting and burning 18 Pruning 19 Treating egg clusters 19 Discovery of the brown-tail moth in America 20 European history of the brown-tail moth 21 Life history of the brown-tail moth 21 The eggs 21 The larva? 21 The pupa; 22 The adults 23 Poisoning effect of brown-tail hairs 24 Natural enemies of the gipsy and brown-tail moths native to America 26 Progress of the state work in Massachusetts, 1890-1900 27 Discontinuance of the state work in Massachusetts 28 Conditions in the infested territory at the .close of the state work 29 Funds expended by the State during the progress of the work 29 Results of discontinuance of the work 30 State work resumed in Massachusetts 31 Beginning of work by the National Government 37 Work l)y the State of Massachusetts 47 Work in the State of Maine 50 Work in the State of New Hampshire 53 Work in the State of Rhode Island 54 Work in the State of Connecticut 56 Inspection of lumber and forest products 51 Danger of introducing the gipsy moth and brown-tail moth from foreign coun- tries.. 60 Experimental work in the control of the gipsy and brown-tail moths 62 5 6 FIELD WOEK AGAINST GIPSY AND BEOWN-TAIL MOTHS. Page. Methods now used in fighting the gipsy moth 63 Cost of methods employed 69 Value of natural enemies in controlling gipsy and broww-tail moths 70 The introduction of parasites and natural enemies of the gipsy and brown-tail moths 71 Value of the work of suppression to the farmer and fruit grower 72 Suggestions to the owners of private property in the infested districts 72 The outlook 74 The more important American publications on the gipsy and brown-tail moths. 77 Index 79 LLUSTRATIONS. PLATES. Pfege. Plate. I. The gipsy moth (Porthetria dispar). Fis- 1. — Male moth. Fig. 2. — Female moth. Fig. 3. — Male pupa. Fig. 4. — Female pupa. Fig. 5. — Egg cluster. Fig. 6. — Caterpillars Frontispiece. II. Woodland area in Massachusetts defoliated by the gipsy moth " 9 III. Fig. 1. — Egg clusters of the gipsy moth on trunk of apple tree, Wallingford, Conn.., December, 1909. Fig. 2. — Egg clusters of the gipsy moth on stone wall 12 IV. The brown-tail moth (Euproclis chri/sorrhcea) . Fig. 1. — Cocoon. Fig. 2. — Male moth. Fig. 3. — Female moth. Fig. 4. — Egg clus- ter on leaf. Fig. 5. — Caterpillars feeding on leaf 22 V. Woodland at Lexington, Mass., completely defoliated by the gipsy moth 38 VI. Same woodland at Lexington, Mass., as that shown in Plate, V, (he following year, illustrating beneficial effects of control work... 38 VII. View of woodland near roadway at Weston, Mass., showing effect of control measures against the gipsy moth 44 VIII. Lumber piles at York, Me., infested with egg clusters of the gipsy moth 00 IX. Fig. 1. — Pine grove killed by the gipsy moth. Fig. 2. — Pine trees that have been protected from the attacks of the gipsy moth 62 X. One of the ten high-power spraying outfits used in the gipsy moth work of the Bureau of Entomology G6 XI. High-power spraying outfit in use in treating roadside trees 60 XII. View showing contrast between trees protected from the gipsy and brown-tail moths and those unprotected 72 XIII. Map showing dispersion and present distribution of the gipsy moth in New England, and limits of area infested by the brown- tail moth, in 1909 74 TEXT FIGURES. Fig. 1. Roadside view in Massachusetts, showing oak and ash trees, the former killed by the gipsy moth (Porthetria dispar) and the latter prac- tically uninjured 14 2. Pine trees killed by the gipsy moth 15 3. Trunk of pine tree, showing tanglefoot band and egg clusters that have been treated with creosote 19 . 4. Winter webs of the brown-tail moth (Euproctis chrysorrhoea) 22 5. Oak tree in winter, showing webs of the brown-tail moth at tips of the branches 23 6. Brown-tail moths on electric light pole, Somerville, Mass., July 2, 1908. 24 7 8 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. Page. Fig. 7. Hairs of the caterpillar of the brown-tail moth, highly magnified l,'5 8. Equipment for roadside work against the gipsy moth, used by em- ployees of the Bureau of Entomology 39 9. Roadside where thinning operations are being carried on, showing tools and equipment used in the work 40 10. Employees of the Bureau of Entomology treating egg clusters of the gipsy moth with creosote, using an ordinary paint brush and a brush attached to a long pole 41 11. Roadside which has been cleared of brush and the trees banded with burlap and tanglefoot : 42 12. Gipsy-moth scout's outfit, consisting of climbing irons, mirror, clean- ing knife, can of creosote, and brush 43 13. Roadsides badly infested by the gipsy moth 44 14. Same road shown in figure 13, after the completion of thinning opera- tions against the gipsy moth 45 15. Map showing roads in Massachusetts where the brush has been cut, the trees thinned, and those remaining treated by employees of the Bureau of Entomology to prevent the spread of gipsy-moth larvae on vehicles « 46 16. Pile of 120,000 webs of the brown-tail moth, gathered and destroyed at York, Me 51 17. Roadside area, showing how the grass has been induced to grow by thinning out the trees and clearing away the underbrush in gipsy- moth control work 64 18. Spraying a roadside, using a combination tower and hand nozzle, so as to throw two streams 68 19. Map of New England, showing the present area infested with the gipsy moth and the brown-tail moth 73 20. Neglected apple orchard in which the trees have been killed by the gipsy moth 74 21. View of a hill where all the timber was cut to prevent its destruction by the gipsy moth; pile of logs in the foreground 75 22. Map of New England, showing areas infested by the brown-tail moth from 1897 to 1909-. 76 Bui. 87, Bureau of Entomology, U. S. Dept. of Agriculture. Plate II. REPORT ON THE FIELD WORK AGAINST THE GIPSY MOTH AND THE BROWN-TAIL MOTH. INTRODUCTION. For nearly two decades eastern Massachusetts has suffered enor- mous loss to its forest, orchard, and shade trees, as well as to orna- mental plantings which beautify many of the large country estates, by reason of the depredations of the gipsy moth (Porthetria (lis par L.) (see PI. II), and for the latter half of this period by the combined injury caused by this insect and the brown-tail moth (Euproctis chrysorrltoea L.). Both of these insects w^ere introduced from Europe, During the past few years the situation became so serious, owing to the spread of these insects into Maine, New Hampshire, Rhode Island, and Connecticut,, that appropriations from the National Government were urged by the States affected, and, owing to the great danger that these pests would become disseminated over the entire country, funds have been appropriated by Congress to assist in securing their control and of preventing further spread. The purpose of this report is to sketch briefly the life histories of the insects concerned, their habits since their introduction into this country, a statement of the injury caused by them here and in their native homes, and to discuss the methods used for their control, in order that this work may become better understood and the danger of the presence of the pests more thoroughly appreciated in sections which are not now infested. Free use has been made of the reports already published by the State of Massachusetts and other New England States, where warfare against these insects has been car- ried on in the past. Acknowledgment and thanks are due to Dr. W. E. Britton, state entomologist of Connecticut, for the use of Plate III, figure 1, and to Prof. E. F. Hitchings, state entomologist of Maine, for the use of Plate VIII and text figure 16. IMPORTANCE OF THE GIPSY MOTH AS AN INSECT PEST IN THIS COUNTRY. During the summer of 1889 great injury was caused to the foliage of the street trees and of those on private estates in Medford, Mass., 9 10 FIELD WOEK AGAINST GIPSY AND BKOWN-TAIL MOTHS. a city about 5 miles north of Boston, by caterpillars which appeared in enormous swarms. In many cases the trees were completely defoliated, antl the insects crawled into the houses and upon the fences and walks, so as to become a public nuisance in the neighbor- hood. Specimens were sent to the office of the Massachusetts state board of agriculture at Boston, and were transmitted to Prof. C. H. Fernald, at Amherst, and, in his absence, were determined by Mrs. Fernald as the gipsy moth of Europe. An investigation in the neigh- borhood showed that this insect had been quite abundant and had caused considerable damage for a number of years, but, owing to the belief of most of the residents that it was one of the common native caterpillars, no action had been taken in the matter. As a result of persistent inquiry among the inhabitants of the infested section it was determined that some of these insects were introduced from Europe, probably in the egg stage, by Prof. Leopold Trouvelot, a French naturalist, about the year 1869. At. that time this gentleman was conducting experiments with silkworms, and also with some of the American species of silk-spinning caterpillars. The evidence seems to show that some of the egg clusters, or young caterpillars, which he secured from Europe, escaped from his house where the experi- ments were being conducted, and, as he was aware of the dan- gerous nature of the insect in its native home, he destroyed all the caterpillars that could be found in the neighborhood and made public the fact that it had escaped. At that time the section in which he resided adjoined a large area of waste land, which was overgrown with sprouts and brush, and here the species became established. Its slow development as a serious pest was undoubtedly due to the fact that this area was burned over periodically by brush fires which destroyed large numbers of the insects, and also to the prevalence at that time of many insectivorous birds, which doubtless accom- plished much in preventing the rapid increase of the species. So thoroughly were the trees defoliated by the caterpillars that in many cases during the summer of 1889 and 1890 swarms of them practically covered the sides of many houses. Ileal estate in the neighborhood rapidly depreciated in value and many tenants moved to more congenial quarters of the city. The recorded state- ments of eye-witnesses of the conditions that prevailed seem almost incredible to one who has had no opportunity to observe the serious damage which this insect causes. Many trees and orchards died as the result of repeated defoliation, and during the winter of 1890, on petition of the city of Medford and the surrounding cities and towns, the matter was brought to the attention of the legislature, and the sum of $25,000 appropriated for abating the nuisance. RECORD OF THE GIPSY MOTH IN ITS NATIVE HOME. H STATE WORK AGAINST THE GIPSY MOTH IN MASSACHUSETTS, 1890 1900. The work against the gipsy moth was phiced in charge of a paid commission of three men, appointed by the governor. At the time the work was begun it was thought that only a small area was infested, but on May 9, 1890, the commission reported to the governor that the infested area was "some sixteen times as large as at first repre- sented, "and requested an additional appropriation of $25,000, which was granted. Early in 1S91 the commission was abolished by the governor and an unsalaried one appointed which carried on the work for a few months, until a law was enacted by the legislature giving the state board of agriculture authorit}^ to use "all reasonable measures to prevent the spreading and to secure the extermination of the Ocneria disjMr or gypsy moth in this Commonwealth." The board placed the work under the immediate direction of a committee, later known as the "Committee on gypsy moth, insects, and birds," which was made up of five of its members, who served without pay. Mr, E. H. Forbush, of Worcester, Mass., was appointed director of the field work, and Prof. C. H. Fernald, entomologist to the Massachusetts agricultural experiment station at Amherst, was given supervision of the experimental and scientific work, and ener- getic measures were at once begun to exterminate the pest, and were continued until February 1, 1900. RECORD OF THE GIPSY MOTH IN ITS NATIVE HOME. A perusal of the European literature concerning this insect, which was thoroughly examined and the results presented in the report on the gipsy moth by Forbush and Fernald, published by the Massa- chusetts board of agriculture in 1896, indicates that it was a pest in nearly all European countries at the time the first entomological writings were published, and there is good reason to suppose that even before that time much serious devastation to trees and forests resulted from it, although it was probably referred to as "the plague," and was believed by the inhabitants to be a scourge sent by the Almighty as a penalty for their wrongdoings. Many cases are on record where this insect became abundant and defoliated thousands of acres of forests, as well as the fruit and shade trees and shrubs in the populated regions. The literature indicates that this moth is abundant periodically and causes enormous loss throughout con- tinental Europe, western Asia, and Northern Africa. It has been found as far north as Stockholm and is known to occur in Algeria. Slight, though not serious, infestations have been reported in Eng- land, and this or a closely allied species occurs in Japan, and is said to be present in sections of China. During the year 1909, Prof. 12 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. Trevor Kincaid, who was engaged by the Bureau of ICntomology, in cooperation with the State of Massachusetts, for the purpose of collecting parasites of this insect in Russia, found during his explo- rations that thousands of acres of forests were completely denuded, and in other localities trees were dying over large areas as a result of previous defoliations. Dr. L. O. Howard, Chief of the Bureau of Entomology, while visiting, in 1909, the corps of European agents engaged in collecting parasites of the gipsy moth in Europe, found a large forest area near Nantes, France, which was completely stripped by this pest. In fact, the whole European history of this moth is a continuous record of periodical outbreaks of greater or less severity, which have caused enormous damage to trees from the time of the earliest writings on entomology down to the present time. The situation in Japan is not as serious as in Europe, owing to the efficient work of certain parasites which tend to keep the insect under control. LIFE HISTORY OF THE GIPSY MOTH. THE EGGS. (PI. I, fig. 5.) The female gipsy moth deposits her eggs in clusters containing normally from 400 to 500 eggs, which are covered with hair from her body; this protects them from the action of the elements and ren- ders their destruction, even by fire, quite difficult. The clusters are fully 1 inch in length and about half as wide, and have the general appearance and color of a small piece of sponge. The number of eggs varies considerably and depends largely on the food supply and the vigor of the caterpillar from which the female develops. In colonies where the food supply has been practically exhausted by the larvse, egg clusters are often found containing not more than 50 or 75 eggs, while, on the other hand, a number of cases are on record where sin- gle clusters contained over 1,000 eggs. The majority of the eggs are deposited about the middle of July, although there is consider- able seasonal and individual variation. Females have been found depositing egg clusters as early as June 25 and as late as October 7. Crevices in the bark, holes in trees, stone walls (PI. Ill, fig. 2), or rubbish piles are favorite places for the deposition of eggs, as they aff"ord shelter for the full-grown caterpillar about to pupate and protect the pupa and the newly emerged moth. Many clusters are deposited under steps or porches of houses, in outbuildings near infested trees, as well as on the trunks (PI. Ill, fig. 1 ) and on the under side of the branches of the trees themselves. Hatching takes place early in the spring, about the time the trees are coming into leaf. A few cases are on record where the caterpillars hatched in the fall, but this is unusual. Bui. 87, Bureau of Entomology^ U. S. Dept. of Agriculture. Pl.ATElll. Fig. 1.— Egg Clusters of the Gipsy Moth on Trunk OF Apple Tree, Wallingford, Conn., December, 1909. I From Britton.) Fig. 2.— Egg Clusters of the Gipsy Moth on Stone Wall. (Original.) [This wall has been ovorturned to expose the egg clusters.] LTFE HTSTOriY OF THE GIPSY MOTH. 13 THE LARV.E. (PI. I, fig. 0.) The newly hutclied caterpillars feed upon (lie small leaves, makin^^ "pin holes" in them. As a rule the caterpillars molt five times, but quite a number of cases are on recorcl where an additional molt took place before they entered the pupal staf;:e. The newly hatched cater- pillars are about one-eio;hth of an inch in lenj^^th and covered with lono-, slender hairs. During warm weather they feed upon the leaves, but when the temperature is low, or durino^ rainy or unsettled weather, such as is common in early spring, they congregate in masses in the crevices of the bark or on the egg clusters from which they hatched. As the w^eather becomes warmer in the early summer, they grow rap- idly and devour the entire leaves except the woody veins. Until they are about half grown, the caterpillars are able to suspend themselves from the twigs or branches of the trees by means of silken threads spun from their bodies, and in this way they often drop upon animals carriages, or other moving objects, and may be conveyed to localities w^here none of the species exists. After the caterpillars have molted the fourth time, which usuall}^ occurs about the middle of June, a con- siderable change in coloration appears. On the dorsum of each of the first five segments behind the head is a pair of prominent blue tuber- cles, while on the following six segments the tubercles are of a dark- red color. The arrangement and coloration of these tubercles is characteristic of the species. The feeding habits change somewhat with the progress in growth of the caterpillars, for after becoming half grown the caterpillars seem to prefer shelter from the sun and feed for the most part at night or during cloudy weather. During the warm part of the day they remain concealed in crevices in the bark, crawl to the ground, or seek any convenient shelter from the sun. This hal)it serves as a protection against their natural enemies, and although in moderately infested sections it is usually possible to find caterpillars feeding at midday during sunny weather, still the ma- jority are either in hiding or are feeding in such situations as to be largely protected from direct sunlight. The period spent in the cater- pillar stage extends, on the average, from early in May to July 5, or is approxhnately seven weeks. Egg clusters deposited in cool situations do not hatch as readily as those more favorably located; hence the entire length of the feeding period varies considerably. Larvae have been found as early as the 1st of April and as late as September 6. In certain areas along the seacoast and on islands which are sur- rounded by tidewater, the hatching of the eggs is retarded, and pupa- tion takes place much later than where conditions are normal. The full-grown caterpillars measure about 2 inches in length, although there is considerable variation in this respect, due largely to the 14 FIELD WORK AGAINST GIPSY AND BEOWN-TAIL MOTHS. amount of food available. It is a noticeable fact that in ])a(l colonies, where most of the foliage has been eaten, the caterpillars pupate early in the season before attaining normal size. This insect has a varied list of food plants; in fact, it will eat almost any kind of vegetation, although it seems to prefer the foliage of oaks (fig. 1), willows, and apple trees. Repeated observations have shown that the ash (fig. 1), juniper, and red cedar are practically immune from attack, while the maple is not injured to any great ex- tent if more desirable food is within easy reach. Grass and garden crops are sometimes seriously injured when the supply of other food has been exhausted. A few years ago a farmer in Lynn, Mass., stated that with the assist- ance of his men he collected several bushels of the caterpillars that were Fig. 1.— Uoadside view in Massachusetts,, showing oak and ash trees, the former killed by the gipsy moth (rorthetria dispar) and the latter practically uninjured. (Original.) feeding in his fiekl of sweet corn. The caterpillars had stripped the trees in a piece of woodland near by, and, after eating all the foliage from the bushes and low growth, had migrated in countless numbers across the road and attacked the growing corn. Most of our native leaf-eating insects confine their diet to a small number of food plants, and it is unusual for a species to feed on both deciduous and coniferous trees. The gipsy-moth larva\ after becom- ing half grown, feed witii avidity on conifers, especially the white pine, and many acres of this, as well as other coniferous trees, have been de- foliated and killed in the infested region of New England (fig. 2). LIFE HISTORY 0¥ THE GIPSY MOTH. 15 The white pine, as well as the spruce and the hemlock, is unable to survive after one complete defoliation, and when only partially de- nuded the trees are usually attacked by bark borers and other insects so that death soon follows. The proper treatment of conifers to pre- vent injury by the gipsy moth will be described farther on in this report. THE pur^. (PI. 1, figs. 3, 4.) After the caterpillars have finished feeding they usually select more or less protected places in which to pupate. Stone walls, rubbish piles, and open spaces beneath porches or outbuildings furnish excel- lent places for caterpillars to enter the pupal stage. Of course, a large nimiber remain on the trees, where they usually pupate on the under side of the branches, beneatii loose bark, or in holes and cavities, or Fig. 2.— Pine trees killed by the gipsy moth. (Original). descend to the base of the trees before transforming. Previous to pupation the caterpillar spins a few threads of silk in order to attach itself firmly. The body then shortens considerably and pu])ation is accomplished by the integument of the segments behind the head splitting dorsally and the whole larval skin is forced back to the entl of the body, the pupa remaining beneath the network of silk which held the caterpillar in place. The pupa is dark reddish-brown, and the body segments bear yellow hairs, which are arranged in groups. From 7 to 17 days are spent in this stage before the moth emerges. As a rule female ])upfe are much larger tlian those of males, but the sex can always be determined by the structure of the last segment of the abdomen. 16 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. THE ADULTS. (PL I, figs. 1, 2.) The male moths ordinarily emerge from the pupte earlier than do the females. The body of the male is light brown and the wings are considerably darker and have prominent black markings. Male moths are able to fly considerable distances and are especially active during warm sunny weather. The zigzag motion of the flight of these moths is characteristic of the species. The body of the female is light buft'. The abdomen, which is very large and almost completely filled with eggs, is densely covered with short yellow hairs which are used by the moth to protect the eggs as they are deposited in the cluster. The wings are white, with prominent black markings, and, although they are apparently of ample size, the female moth is not able to fly on account of the weight of the body. The adult insects take no food, and after mating, which takes place soon after emergence from the pupa, the female begins depositing eggs. As a rule the egg cluster will be found near the pupal case from which the female emerged, but occasionally the moth will crawl a considerable distance, especially if disturbed. When a search for egg clusters is being made the dis- covery of a female pupal case is indication that an egg cluster is pres- ent near by. Sometimes motlis which emerge from pupse that are attached to the branches of trees fall to the ground and deposit their eggs on the trunks of surrounding trees or on leaves or rubbish. By the time the egg cluster is completed, the abdomen has shrunken greatly and in a few hours the moth dies. METHODS EMPLOYED IN WORK AGAINST THE GIPSY MOTH. SCOUTING. As the law enacted by the Massachusetts legislature in 1891 required the state board of agriculture "to prevent the spread and secure the extermination" of this insect, a determined effort was made to ascer- tain the extent of the area infested. Men were trained so that they were able to recognize the moth in all its stages, and as soon as they hatl secured sufficient experience the most expert ones were sent into the territory not known to be infestetl to make a thorough inspection. As a result of this work, it was found that, while the area supposed to be infested in 1890 covered 9 cities and towns in whole or in part and embraced about 50 square miles, the pest had become established in. more oi- less numbers in .30 cities and towns, covering an area of 200 square miles. This spread had undoubtedly been going on for a num- ber of years, and as the thickly settletl sections became badly infested the small cater])illars were easily conveyed long distances owing to their habit of spinning down from trees onto vehicles or other moving METHODS EMPLOYED AGAINST GIPSY MOTH. 17 bodies. Many colonies were discovered on the premises of milkmen and market gardeners who made regular trips to the infested section to distribute their products. SPRAYING. It was at first believed that this insect could be successfully con- trolled, like most other leaf-eating species, by spraying the trees with Paris green, a remedy which was then in common use. Experiments, however, showed that it was impossible to kill the caterpillars with this spray after they became half grown, unless it was used so strong that it resulted in severe injury to the foliage of the trees. Mr. F. C. Moulton, who conducted an extensive investigation with insecticides in the years 1891 and 1892, was able to prepare a new insecticide, arse- nate of lead, which could be used in sufficient strength to kill the caterpillars without injuring the foliage. This work was later taken up by Messrs. A. 11. Kirkland, F. J. Smith, and A. F. Burgess, under the direction of Prof. C. II. Fernald. A large number of experiments were made, using different formulas, which demonstrated the practical effectiveness of this poison and the proper method of its preparation. The poison as used at that time w^as made by dissolving the proper amounts of arsenate of soda and acetate of lead salts in separate ves- sels containing water. These solutions were then brought together and a precipitate, consisting of arsenate of lead, was formed. Usually the fresh precipitate was prepared in the field. In recent years, since this poison has come into general use throughout the country for treat- ing trees infested with leaf-eating insects, it is made by manufacturers in a similar way, and is put on the market in the form of a paste which mixes readily with water, thus preventing the delay occasioned by mixing the raw chemicals and obviating the danger of securing impure materials, wdiich might cause injury to the foliage or crop treated. Some improvements were made in spraying machinery, which was very crude when we consider the equipment used at the present time. Spraying with the facilities tlien at hand was a very expensive opera- tion, and in many cases gave unsatisfactory results, especially when large trees were treated. Owing to these facts, and because every effort was being made to secure the extermination of the insect, spraying was undertaken only in a limited way. BURLAPPING. The secretive habits of the caterpillars suggested the provision of artificial hiding places, and for this purpose burlap bands were placed about the trunks of the trees. Bolts of burlap were cut into strips about 8 inches wide, which were rolled for the convenience of the workmen. A band was placed around each tree about as high as a 40705°— Bull. 87—10 2 18 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. man's shoulder and fastened in the center with twine, the upi)er ])art being fohled down, forming an exceUent slielter for the caterpihars. By examining the burhips frequently and crushing the larvae untler- neath great progress was made in destroying the pest. The free edges of the burlap should be kept loose from the trees so that the larvse can easily crawl under the folds. This method can not be used advantageously until the caterpillars are about half grown, as they do not often seek shelter until that time. The expense entailed is considerable, but it is one of the most effective measures where exter- mination of the insect is desired. STICKY BANDS. Numerous attempts were made to use a sticky material, such as printer's ink, tar, or other substances, applying them to bands of tarred paper on the trunks of trees to prevent the caterpillars from ascending. Several tons of a German product, known as "raupen- leim," were tried but none of these preparations proved satisfactory for wholesale use. Success in using such bands was not attained until the material known as tanglefoot came into use, about live years ago. CUTTING AND BURNING. In order to prepare infested territory so that it could be treated effectively and economically, it was necessary to cut out and burn the brush and sprout growth, as well as trees that were hollow and partially decayed. This method reduced to a minimum the number of trees to be burlapped or otherwise treated, and by removing the low growth the larvae were forced to feed on the trees where they could be more easily destroyed. A method employed against the young caterpillars hatched from egg clusters located in stone walls or rocky areas was to clean out all brush and undergrowth during the winter. As soon as the larvae appeared in the spring the ground and walls were burned over by using a device known as a cyclone burner. This consisted of a 15- gallon oil tank, on which was mounted a small force pump. The oil was conducted through a hose to an iron extension rod, at the end of which a nozzle of the Vermorel type was fitted. The fine mist of oil forced from the nozzle was ignited and the ground and walls burned over. To secure best results a large ball of flame should be maintained which can be forced into the cracks or cavities in walls or ledges in order to destroy the larvae. Paraffin gas oil or a light grade of crude petroleum can be used. Two men are required to operate this outfit satisfactorily. The action of the oil soon destroys the hose, so that it seldom lasts more than one season. METHODS EMPLOYED AGAINST GirSY MOTH. 19 PRUNING. As the foiiialc moths deposit their eg^" ciusters iindei' h)ose l);irk and in holes and cavities in the trees, and also ))ecause the larvie seek such hiding places, it became necessary to rid the trees of these natural shelters. To accomplish this purpose a considerable amount of pruning and fillmg of cavities was required. This work had to be skillfully done, especially when fruit or shade trees in cities or towns were treated. Many ingenious methods were devised for carrying on these operations, some of which have been adopted by j)rofes- sional foresters and others who have taken up the business of caring for trees. TREATING EGG CLUSTERS. The insect exists in the egg stage nearly nine months in the year and many experiments were tried to determine the most ef- fective method of treating egg clusters. The first method used was that followed in Euroi)e and consisted simply in scra{)iiig ofl' the egg masses and burning them. In removing the eggs many were scatteretl, even if the work was carefully done, and as such eggs hatched in due time it became necessary to secure a better method of treatment. It was found that they could be killed by satiu'ating the clusters with crude coal-tar creosote to which was added a small amount of either coal tar or lampblack to discolor them and enable the workmen to tell instantly the ones that had been treated. (See fig. 3.) It was necessary to make a very thorough search of all objects likely to harbor egg clusters if satisfactory results were expected, and this required much climbing of high trees as \ve\\ as careful ground work. The pupse and moths were crushetl or treated with creosote when found by the workmen. It was necessary to apply a combination of methods to secure satisfactory results and many localities had to receive special treat- FiG. 3.— Trunk of pine tree, showing tanglefoot band and egg clusters that have been treated with creo- sote. (Original.) 20 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. ment on account of their location and condition of infestation. Methods which could be readily applied in wooded areas were entirely unsuited for use in residential sections. DISCOVERY OF THE BROWN-TAIL MOTH IN AMERICA. The work on the ^ipsy moth resulted in a <^reat reduction of the numbers of the insect and a steady improvement in the condition of the infested territory, in spite of the fact that the legislature seldom granted the appropriations which were deemed absolutely necessary by the board of agriculture, and the availability of the funds was often delayed so that many of the trained men were thrown out of employment for a part of the year, which of course greatly affected the efficiency of the force. To add to the didiculties of the situation complaints were received during the summer of 1897 that trees and shrubs in Somerville, Mass., were being severely injured by an insect which appeared to be new to the region. An investigation showed that the trouble was caused by the brown- tail moth {Euproctis chriisorrhoRa L.), an insect well known and at times as noxious in Europe as the gipsy moth. Carefid inquiry indicated that this species was probably imported from Europe a few years before on rose or nursery stock by a local florist. The attention of the governor was called to the matter by the state board of agriculture, and, realizing the seriousness of the pest and the desirability of stamping it out at once, he sent a special message to the legislature, which was then in session, suggesting that action be taken without delay. A law was passed requiring })roperty owners to destroy the insects on their premises, and the opportunity for stamping out the pest before it could become generally disseminated was lost. As is always the case, some of the citizens and numicipalities made every effort to destroy the pest, but through the neglect and indifference of others little permanent good was accomplished. The following year $10,000 was diverted from the gipsy moth appropriation to "prevent the spread of the brown-tail moth," but the money did not become available for use until after the cater- pillars had left their winter webs and begun feeding. Thus the insect was allowed to spread for two seasons after it was discovered, because the work was not taken up promptly under proper supervision. When work was begun it was found that the insect had spread over a large territory and it seemed almost impossible to stamp it out. A detailed account of this insect was prepared by Fernald and Kirkland in 1908 and published by the Massachusetts board of agriculture. LIFE HISTORY OF THE BROWN-TAIL MOTH. 21 EUROPEAN HISTORY OF THE BROWN-TAIL MOTH. The brown-tiiil moth is one of the oldest known i)ests in Europe and is called in many of the earlier writings "la commune/' or the communistic one. It is said to be distributed over central and southern Europe and to extend to Algiers on the south and the Himalayas on the east. It has been found in limited numbers in England and may be present in Japan, although the record from the latter country is somewhat doubtful. Few, if any, species have caused more havoc to foliage than has this one, and many accounts of its destructive work have been recorded. Deciduous forest and fruit trees are often denuded, and even garden crops sometimes suffer from the enormous numbers of the caterpillars. Similar conditions now prevail in some sections of Europe, for during the spring of 1909 thousands of seedling trees, badly infested with the webs of this insect, were shipped to this country from nurseries in France. Mr. II. I^. Frost, of Arlington, Mass., informed the writers that while in Germany during the summer of 1909 he found that the Thiergarten in Berlin, a large park, had been closed to the public owing to the large numbers of larvje of the insect which were defoli- ating the trees. The action of the officials in closing this park was in part due to the serious poisoning of people as a result of coming in contact with caterpillars while visiting the grounds. Dr. L. O. Howard, Chief of the Bureau of Entomology of this Department, states that he observed this insect i)resent in injurious numbers in certain sections of Europe, particularly in France, during the summer of 1909. LIFE HISTORY OF THE BROWN-TAIL MOTH. THE EGGS. (PL IV, fig. 4.) The female brown-tail moth deposits her eggs in a single elongated cluster on the undersitle of a leaf, usually near the end of a twig, covering it with brown hair from the end of her body. Each cluster is about tw^o-thirds of an inch long and contains from 200 to 400 eggs which are nearly globular, and yellow. The eggs are deposited during the first three weeks in July, and hatching takes place in from 15 to 20 days. THE LARV..E. (PI. IV, fig. 5.) After hatching the young larvje begin feeding on the epidermis of the leaf on which the egg cluster was deposited and later attack others near by. They are gregarious and usually feed on the terminal leaves of the twigs, which are drawn together and held in position 22 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. by silk s})un by the caterpillai-s. As the season advances more leaves are drawn into tlie web, and this is lined with silk and serves during the winter as a hibernaculum for the larvae. The caterpillars do not remain in a single large cell. The web is divided by cross partitions into small pockets in each of which one or more of the larvie remain during the winter. The webs (hg. 4) are very con- spicuous on the trees during the winter, as they are usually located at the tips of the branches. (See fig. 5.) During the first warm days of spring the caterpillars come forth from the webs and begin feeding on the bursting buds. In cases where the trees are badly infested the tiny leaves are devoured as fast as they develop. The caterpillars feed until about the 20th of June before becoming full grown. They molt four or five times in the spring, and when ready Fig. 4.— Winter wel.>s of the lirown-tail moth (£i-/;TOC/;6- chiyMirUaa). ((.)riginal.) to spin their cocoons are about an inch and a half in length. The body is nearly black and co veered with rows of yellow spines and bar"bed hairs which arise in tufts on the back and sides. There is also a row of nearly white tufts on the full-grown larvae, which arise along each side of the dorsal abdominal segments. The next to the last two segments each bear a small coral-red tubercle on the dorsal part. As soon as the caterpillars are full-fed they seek shelter and spin up loose cocoons, within which they pupate. THE PUP^. The cocoons (PI. IV, fig. 1) may often be found in leaves which have been weblied together by the larvae, in crevices in the bark, Bui. 87, Bureau of Entomology, U. S. Dept. of Agriculture. Plate IV. The Brown-tail Moth (Euprogtis chrysorrhcea). Fig. 1. — Cocoon. Fig. 2.— Male moth. Fig. 3. — Female moth. Fig. 4.— Egg cluster on leaf. Fig. b. — Cateri)illar.s on leaf. (Original.) LIFE HISTORY OF THE BROWN-TAIL MOTH. 23 under Ijiirlaps, beneath tlie clapboards or under the eaves of houses, or in any situation which affords reasonable shelter. As a rule the cocoons will be found in masses, and, as the silk with which they are constructed is interwoven with hairs from the bodies of the caterpillars, severe poisoning; may result in removing them from their resting })laces. The i)U})al stage lasts about 20 days, most of the moths emerging during the first 10 days in July. Weather con- ditions during the spring serve to accelerate (U- retard the growth of the caterpillars, so that the time of pupation and emergence of the moths varies considerably. THE ADULTS. (PI. IV, figs. 2, 3.) Both males and females are white and bear a tuft of yellowish-brown hairs at the end of the abdomen, from which the name" brown-tail moth " is derived. Although the abdomen of the female is much larger than that of the male, the female of the brown- tail moth, unlike that of the gij^sy moth, is capable of strong flight, and the spread of the species is there- fore not handicapped as in the case of the latter species. Both sexes fly more fre- c^uently at night than in the daytime, although most of the eggs are deposited dur- ing the day. The moths are attracted to strong light, especially electric arc Hghts in cities and towns, and during the nights when the moths are most abundant the areas around these lights sometimes have the general appearance of a heavy snowfall, due to the great number of flying insects. Stores and houses in the neighborhood are often invaded by the moths, and several cases are on record where merchants have been obliged to close their stores during the height of a moth flight in order to prevent annoyance and trouble caused by the enormous num- FiG. 5.— Oak tree in winter, sliowing webs of the l)ru\\n-fail moth at tips of branches. (Original.) 24 FIELD WORK AC4AINST GIPSY AND BROWN-TAIL MOTHS. bers of these insects. The morning following a flight, tlie houses, telephone poles, and trees in the immediate vicinity of the arc lights are usually well covered with small white moths (see fig. 6) ; and it is no uncommon thing for lamp trimmers to collect one or two quarts of dead moths inside the globe surrounding a light. The hairs from the abdomens of the moths are poisonous, as well as those from the cater])illars, and a great many persons have been caused severe incon- venience by coming in contact with the adult insects. The moths' habit of flying to lights serves to increase their distribution, especially in the more thickly populated regions. Large numbers of the insects are killed, however, b}^ coming in contact with the liglit and many of the survivors are de- stroyed by birds the morning following the flight. The English sparrow has been observed by ]\Ir. Kirkland to kill large numbers of the moths which remained about the lamps by jndling off the wings and devourino; tlie bodies. POISONING EFFECT OF HAIRS. BROWN-TAIL From the time this insect was first found in Somerville numerous reports were re- ceived that the caterpillars were poisonous to human beings. Many people were severely affected with what was termed "the brown-tail rash," and niuch com- ])laint arose on that account. The best explanation of the trouble was that the barbed hairs of the caterpillars (fig. 7), when they came in contact with human skin, caused severe irritation. The scratching to relieve this itching forced the hairs farther into the tissue, which resulted in a slight swelling and an intense burning and stinging sensation. When the housewife swept the caterpillars from the porch or brushed down the cocoons, which are interlaced with larval hairs, many were broken, and as a result severe cases of brown-tail rash followed. Fig. 6.- Brown-tail moths on eleo trie light pole, Somerville, Mass. July 2, 1908. (From Kirkland.) POISONING EFFECT OF BROWN-TAIL HAIRS. 25 The motlis arc provided with these barbed haiis, but to a less extent than tlie Larva^,, and cases of ])oisonin,<,' have been re])orted during the flight of moths in the summer. Broken hairs wliich float in the air when the caterpiUars, webs, or cocoons are (Hsturbed also cause severe internal irritation and poisoning if the (kist is inlialed or swallowed in any considerable quan- P'lG. 7.— Hairs of the caterpillar of the brown-tail iiiolh, highly magnified. (Adapted from Kirklaud.) tities. The poisoning has caused very serious illness to men engaged in the work against the moths, in the field, and at the Parasite Labo- ratory, and each year many are obliged to seek other employment, and not a few have been under a physician's care. The death of one man was due to severe internal poisoning contracted while employed on the work, particularly while turning burlaps. 26 FIELD AVORK AGAINST GIPSY AND BROWN-TAIL MOTHS. Underclothes and bedding' should not he ])ut out upon the line durino; the caterj)illar season, as the floating hairs may alight on such articles, which, when used, may result in serious poisoning. During the year 1906 a careful study of this dermatitis was made by Dr. E. E. Tyzzer, of the Harvard ISfedical School, and a rei)ort was published by liim." He concludes from his investigation that the barbed hairs not only cause a mechanical irritation but that they contain a poison which acts directly on the corpuscles of the blood. This results in a break- ing down of the corpuscles to a certain extent and in their assuming a jagged outline instead of a circular one. Such a multitude of people have suffered from this form of poison- ing that many remedies have been prepared and sold whicli are warranted to give relief. During the summer metropolitan news- papers and many of the smaller papers in New England contain advertisements of remedies for the brown-tail rash. The trouble is more serious during liot weather, when ])ei'S()ns are perspiring freely, and tlie skin at this time seems less resistant to the entrance of the spines. Some of the advertised remedies give a certain measure of relief, but none of the remedies suggested is wholly eflicacious. Applica- tions which are cooling to the skin, such as witch-hazel or alcohol, serve to allay the irritation to some extent and reduce the suffering caused by the poison. The internal irritation which is caused by breathing or swallowing the ])ois()nous hairs is often very serious and no effective remedy has been found. NATURAL ENEMIES OF THE GIPSY AND BROWN-TAIL MOTHS NATIVE TO AMERICA. Aside from the experimental work on insecticides and a careful, detailed study of all phases of the life history and habits of the gipsy and brown-tail moths, considerable time was devoted by the Massa- chusetts authorities to an investigation of the native natural enemies which attack them in the field. Both species are partially controlled in Europe by parasites and predaceous enemies, and it was desirable to ascertain if the closely related beneficial species in this country were showing any marked tendency toward controlling the pests. Field observaticms on birds were made by Mr. Forbush, who was ably assisted in this work by Messrs. J. A. Farley and F. H. Mosher, the late Charles E. Bailey, and numerous other careful observers. A large number of native insectivorous birds were found feeding on o In Second Annual Report of the Superinteiuhnit for Suppressing the (iypsy and the Brown-tail Moths, Boston, 1907, pp. 154-168. STATE WORK IN MASSACHUSETTS, 1890-1900. 27 the gipsy moth. Many of the observations have heeii published in the report 1)V Forbush and FernakI ah'eady cilt'tl. Unfortunately, conditions in the territory infested were not very favorable to the increase of insectivorous birds, and tliis, of course, served to limit their activities and usefulness. A few s]:)ecies, among which may be mentioned the crow, while destroying many of the larvae, undoubtedly aided the spread of the gipsy moth by dropping live caterpillars in uninfested sections. Field observations were made and work in rearing the insect enemies of these moths was carried on by Messrs. A. H. Kirkland, A. F. Burgess, F. H. Moslier, and others. A few species of hymenopterous and dipterous parasites were fountl working in the field and small numbers of the adults were reared at the insectary. Among the ])redaceous enemies were several species of beetles (Carabidfe) and stink bugs (Pentatomidse) which were found feeding on the larvae in the field and were studied in detail in the laboratory. Although not an insect, the common toad shoidd be mentioned as doing valuable work in destroying such specimens of the insects as came within its reach. The rapid development and unprecedented injury caused by the gipsy moth after the state work was abandoned show conclusively that native natural enemies are entii-ely unable to cope with the situation. PROGRESS OF THE STATE WORK IN MASSACHUSETTS, 1890-1900. The administration of any extensive public work almost invariably arouses more or less antagonism, and the gipsy moth work was no exception in this respect. In compliance with the provisions of the law which provided for the extermination of this insect, no effort was made to introduce its parasites or natural enemies from abroad, as it would have been necessary to allow extensive colonies of the insect to remain untreated in order to give introduced parasites an oppor- tunity to become established. Some criticism was occasioned by this manner of handling the work and in addition to this many property owners in sections of the State which were not infested failed to see the necessity for making large appropriations to destroy the insect. Active opposition developed in some sections of the infested territory, which was occasioned by ignorance as to the methods of carrying on the work. Realizing that the work was of a different character from any that had been attempted previously, and that new methods and devices must be employed to handle the problem with any degree of success, great effort was made to test in a practical way any suggestions that 28 FIELD WOEK AGAINST GIPSY AND BROWN-TAIL MOTHS. seemed to liave a bearing on reducing the expense of making the work more effective. From the time the iirst state approj)riation was made until the close of the work the gipsy moth committee procured expert opin- ions from the leading entomologists of the country, and during this period a large nund)er of prominent scientists visited the territory, inspected the work, and witiiout exception reported that the exter- mination of tlie gipsy motli was not only ])i-acticable but feasible and that it could be accomplished provided proper financial support was given the work. In the winter of 1S94-1895 an unsuccessful attempt was made to secure national aid in exterminating this insect. A bill, carrying an appropriation for $40,000, was passed by the United States Senate, but it was defeated in the conference commit- tee. During the session of Congress, 1896-1897, an appropriation was made for an investigation of the ravages of the gipsy moth in this country. Dr.L. O. Howard, Chief of the Bureau of Entomology, made several visits to the infested territory and thoroughly examined the conditions and the work which was being done. Mr. C. L. Marlatt, first assistant entomologist, also made a visit to the infested district and investigated the condition of the territory. The report of Doctor Howard" highly commended the work which had been done and stated his opinion that the extermination of the gijisy moth could be accomplished. During the winter of 1897 the Massachusetts Society for the Promotion of Agriculture secured the services of Dr. John B. Smith, state entomologist of New Jersey, to investigate the work and report the conditions found. The report strongly favored contin- uing the work and expressed the opinion that the insect could be exterminated if sufficient funds were appropriated, but the society did not publish the report in full. The condition of the infested territory continued to improve. The residential sections were in excellent condition in 1899, although small numbers of the insect were present. Many woodland colonies had been entirely extermi- nated, as evidenced by the fact that none of the insects had been found for three successive years. The spread of the brown-tail moth, however, continued each year and little hope was entertained of being able to exterminate it. DISCONTINUANCE OF THE STATE WOBK IN MASSACHUSETTS. At the annual session of the legislature in the winter of 1900 a special committee was appointed to investigate the gipsy-moth work. After numerous hearings it was reported that the insect need not be considered a serious pest, and further that "we find no substantial proof that garden crops or woodlands have suffered serious or lasting oBuL II, n. 8., Division of Entomology, U. S. Dept. of Agriculture. FUNDS EXPENDED BY THE STATE, 1800-1900. 29 injury or arc likely, with that precaution or oversight which prudent owners are disposed to give their own interests, to be subjected to that devastation which one would have the right to anticipate from these reports. It appears to us that the fears of the farmers through- out the State have been unnecessarily and unwarrantably aroused, evitlently for the purpose of securing the effect of those fears upon the matter of annual appropriations * * * "yVe do not share these exaggerated fears and the prophesies of the devastation and ruin are unwarranted and in the most charitable view are but the fallacies of honest enthusiasts." As a result of the report of this committee no further appropriation was made for carrying on the work. The tools and equipment which had been used were ordered sold, and the insect was allowed to develop without restriction. CONDITIONS IN THE INFESTED TERRITORY AT THE CLOSE OF THE STATE WORK. As before stated, the area found infested in 1891 included 30 towns and cities, covering 200 square miles. Between the years 1891 and 1900 isolated colonies were discovered beyond these limits in Brook- line, Burlington, Danvers, Georgetown, Manchester, Newton, and Lincoln. These infestations were given special attention and several of them were practically exterminated before the work was discon- tinued. Vigorous measures were enforced over the entire infested territory and all of the w^orst colonies, including those in the wood- lands, had been reduced to such an extent that the extermination of the insect was practically assured. Several towns had been com- pletely cleared of the insect, and the residential sections showed no defoliation, and considerable search was necessary for a nonexpert to secure specimens of the insect. FUNDS EXPENDED BY THE STATE DURING THE PROGRESS OF THE WORK. During the progress of the work the following amounts were asked for and received for the suppression of the pest : Year. Amount asked. Amount appropriated. 1890 S50,000 50, 000 75, 000 165,000 165, 000 200, 000 200,000 200, 000 200, 000 200,000 200, 000 S50, 000 50,000 75,000 100,000 100, 000 150,000 100, 000 150,000 200, (K)0 200, 000 1891 1892 1893 1894 1895 " "" 1896 1897 1898 1899 1900 • Total expenditure 1,175,000 30 FIELD WORK AGAINST GIPSY AND BKOWN-TAIL MOTHS. RESULTS OF DISCONTINUANCE OF THE WORK. During the years 1900 and 1901 little notable injury was caused by the gipsy moth and little attention was paid to it. In the winter of 1902 a small pamphlet was issued by the state board of agriculture setting forth the fact that the moth w^as increas- ing to an alarming extent in many of the wooded districts and predicting that unless all signs failed enormous injury would result. Mention was also made of the fact that about 4 square miles had been found infested in Providence, R. I., during the summer of 1901. This was the first infestation found outside the State of Massachu- setts, and from its location it was believed that the insects had been purposely liberated by some malicious person. At this time tlie brow^n-tail moth had spread rapidly in a northeast direction throughout eastern Massachusetts and into New Hampshire and Maine. Already many persons were being poisoned severely by the caterpillars, especially in the sections around Boston, where the moths were becoming abundant. During the next two years the gipsy moth increased to such an extent that thousands of acres of woodland were defoliated. The caterpillars appeared in such swarms as to denude the orchards and ornamental trees in most of the sections which were previously infested. Large areas of pine timber died as a result of the work of the pest, and real estate values rapidly depreciated in the worst infested sections. Valuable shade trees were killed outright or injured to such an extent that they had to be cut down, owing to their unsightly appearance. The caterpillars swarmed into the houses, covered fences, and spun down from the trees upon the clothing of pedestrians, so that they became an unbearable nuisance. Some of them fell upon teams or automobiles and were carried long distances and served to establish new colonies. Stories of the immense numbers of caterpillars seem almost incredible. On several occasions trolley cars were prevented from running until the tracks were cleared of the crushed and swarm- ing insects. The following spring it was necessary for many of the motormen to wear veils to keep their eyes and faces free from the caterpillars which swarmed from the trees. Acres of forest died as the result of the ravages of the caterpillars, the injury including both hardwood trees and conifers. In fact, the conditions which existed in Medford in 1890 were very mild compared with those in the area infested in 1904. To make matters worse, the brown-tail moth appeared at this time in alarming numbers. Thousands of persons were poisoned by the hairs of this insect, and young children espe- cially sullered severely. Physicians reported many cases of this STATE WORK RESUMED IN MASSACHUSETTS. 31 kind, and general aj)peal was made that something be done to abate the nuisance. During the summer of 1904, Mr. C. L. Marlatt, first assistant ento- mologist of this Bureau, visitetl the infested territory and strongly urged that the matter be given immediate attention. In his report on the conditions existing, which has been published in Circular 58, Bureau of Entomology, he stated that at the time his observations were made the property owners in the badly infested section were at a conservative estimate spending more "than $200,000 annually in fighting the gipsy moth, and that the results were far from satisfactory owing to the fact that the work was not carried on in a systematic manner. The amount cited represents the largest annual appropria- tion which had been made by the State before the work was discon- tinued. All these factors led to the formation of many local associations which had for their object the destruction of the moths. Many of the infested towns and cities appropriated funds which were used to protect the trees, and the citizens, after becoming thoroughly aroused, fought the pests vigorously as a matter of self-j)rotection. The work, however, was far from effective because it was not properly organized and undertaken in a systematic manner, and while many owners had their premises well taken care of, their efforts were largely nullified by the negligence of careless neighbors or nonresident property owners. This was particularly true on estates adjoining wooded areas which had a small market value. The brown-tail moth, which had confined most of its energies up to the present time to feeding on fruit and ornamental trees, w^as now found widely scattered throughout the woodlands, and the trees, especially oaks, in many regions were thoroughly infested with webs of the pest. STATE WORK RESUMED IN MASSACHUSETTS. So serious was the situation and so urgent were the appeals for assistance that the Massachusetts legislature took action in the mat- ter in 1905. The law was amended in 1906 and is given in full, as it has formed the basis for similar laws in other States. [Chap. 381, acts of 1905, as amencied by chap. 2GS, acts of 190G.] AN ACT To provide for suppressing the gypsy and brown tail moths. Be it enacted, etc., as follows: Section 1. For the purposes of this act the pupje, nests, eggs, and caterpillars of the gypsy and brown tail moths and said moths are hereby declared public nuisances, and their suppression is authorized and required; but no owner or occupant of an estate infested by such nuisance shall by reason thereof be liable to an action, civil or criminal, except to the extent and in the manner and form herein set forth. Sec. 2. The governor, by and with the consent of the council, shall appoint a super- intendent for suppressing the gypsy and brown tail moths and shall determine hia 32 FIELD WORK AGAINST GIPSY AND BEOWN-TAIL MOTHS. salary. The governor may, with the consent of the council, remove said superintend- ent at any time for such cause as he shall deem sufficient. In case of the death, removal, or resignation of the superintendent the governor shall forthwith appoint a successor. On or before the third Wednesday in January in each year the superin- tendent shall make a report of his proceedings to the general court, which shall be a public document and shall be printed. Said report shall separate so far as is practi- cable the expenditures on work against the gypsy moth from those on work against the brown tail moth in each city and town. Sec. 3. [As amended by section 1, chapter 268, acts of 1906.] The said superin- tendent shall act for the Commonwealth in suppressing said moths as public nuisances, in accordance with the provisions of this act. For this purpose he shall establish an office and keep a record of his doings and of his receipts and expenditures, and may, subject to the approval of the governor, make rules and regulations governing all operations by cities, towns or individuals under this act. He may employ such clerks, assistants and agents, including expert advisers and inspectors, as he may deem necessary and as shall be approved by the governor. He may make contracts on behalf of the Commonwealth; may act in cooperation with any person, persons, corporation, or corporations, including other States, the United States, or foreign gov- ernments; may conduct investigations and accumulate and distribute information concerning said moths; may devise, use and require all other lawful means of sup- pressing or preventing said moths; may lease real estate when he deems it necessary, and, with the approval of the board in charge, may use any real or personal property of the Commonwealth; may at all times enter upon the land of the Commonwealth or of a municipality, corporation, or other owner or owners, and may use all reasonable means in carrying out the purposes of this act; and, in the undertakings aforesaid, may, in accordance with the provisions of this act, expend the funds appropriated or donated therefor; but no expenditure shall be made or liability incurred in excess of such appropriations and donations. Sec 4. [As amended by section 2, chapter 268, acts of 1906.] Cities and towns by such public officer or board as they shall designate or appoint, shall, under the advice and general direction of said superintendent, destroy the eggs, caterpillars, pupae, and nests of the gypsy and brown tail moths within their limits, except in parks and other property under the control of the Commonwealth, and except in j^rivate prop- erty, save as otherwise provided herein. When any city or town shall have expended within its limits city or town funds to an amount in excess of five thousand dollars in any one calendar year, in suppressing gypsy or brown tail moths, the Commonwealth shall reimburse such city or town to the extent of fifty per cent of such excess above said five thousand dollars. Cities or towns, where one twenty-fifth of one per cent of the assessed valuation of real and personal property is less than five thousand dollars, and where the assessed valuation of real and personal property is greater than six million dollars, shall be reimbursed by the Commonwealth to the extent of eighty per cent of the amount expended by such cities or towns of city or town funds in suppressing the gypsy and brown tail moths in any one calendar year, in excess of said one twenty-fifth of one per cent. In the case of towns where the assessed valuation of real and personal property is less than six million dollars, after they have expended in any one calendar year town funds to an amount equal to one twenty-fifth of one per cent of their assessed valuation of real and personal property, the Commonwealth shall expend within the limits of such towns, for the purpose of suppressing the gypsy and brown tail moths, such an amount in addition as the superintendent with the advice and consent of the governor shall recommend. Disbursements made by said last named towns in excess of said one twenty-fifth of one per cent shall be reimbursed by the Commonwealth every sixty STATE WORK RESUMED IN MASSACHUSETTS. 33 days; but in the case of all others the Commonwealth shall reimburse cities and towns annually accordinis; to the provisions of this act. No city or town shall be entitled to any reimbursement from the Commonwealth until it has submitted to the auditor of the Commonwealth itemized accounts and vouchers showing the definite amount expended by it for the purpose of this act; nor shall any money be paid out of the treasury of the Commonwealth to cities or towns, pursuant to the provisions of this act, until said vouchers and accounts have been approved by the superintendent and the auditor of the Commonwealth. For the purposes of this section the years nineteen hundred and five and nineteen hundred and seven shall l^c considered half years, and the valuation for the year nineteen hundred and four shall be taken as a basis. Sec. 5. [As amended by section 3, chapter 268, acts of 1906.] When, in the opinion of the superintendent, any city or town is not expending a sufficient amount for the abatement of said nuisance, or is not conducting the necessary work in a proper man- ner, then the superintendent shall, with the advice and consent of the governor, order such city or town to expend such an amount as the superintendent shall deem neces- sary, and in accordance with such methods as the superintendent, with the consent of the governor, shall j)rescribe: Provided, That no city or town where the assessed valuation of real and personal property exceeds six million dollars shall be required to expend, exclusive of any reimbursement received from the Commonwealth, during any one full year more than one fifteenth of one per cent of such valuation, and that no town where the assessed valuation of real and personal property is less than six million dollars shall be required to expend, exclusive of any reimbursement received from the Commonwealth, during any one full year more than one twenty-fifth of one per cent of such valuation. For the purposes of this section the valuation of the year nineteen hundred and four shall be used. Any city or town failing to comply with the dii'ections of the said superintendent in the performance of said work within the date specified by him shall pay a fine of one hundred dollars a day for failure so to do; said fine to be collected by information brought by the attorney-general in the supreme judicial court for Suffolk County. Sec. 6. [As amended by section 4, chapter 268, acts of 1906.] The mayor of every city and the selectmen of every town shall, on or before the first day of November in each year, and at such other times as he or they shall see fit, or as the state superin- tendent may order, cause a notice to be sent to the owner or owners, so far as can be ascertained, of every parcel of land therein which is infested with said moths; or, if such notification appears to be impracticable, then by posting such notice on said parcels of land, requiring that the eggs, caterpillars, pupte and nests of said moths shall be destroyed within a time specified in the notice. When, in the opinion of the mayor or selectmen, the cost of destroying such eggs, caterpillars, pupae, and nests on lands contiguous and held under one ownership in a city or town shall exceed one half of one per cent of the assessed value of said lands, then a part of said premises on which said eggs, caterpillars, pupae or nests shall be destroyed may be designated in such notice, and such requirement shall not apply to the remainder of said premises. The mayor or selectmen may designate the manner in which such work shall be done, but all work done under this section shall be subject to the approval of the state superintendent. If the owner or owners shall fail to destroy such eggs, caterpillars, pupaj or nests in accordance with the recjuirements of the said notice, then the city or town, acting by the public officer or board of such city or town designated or appointed as aforesaid, shall, subject to the approval of the said superintendent, destroy the same, and the amount actually expended thereon, not exceeding one half of one p6r cent of the assessed valuation of said lands, as heretofore specified in this section, shall be assessed 40705°— Bull. 87—10 3 34 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. upon the said lands; and such an amount in addition as shall be required shall be a])p()rtioned between the city or town and the Commonwealth in accordance with the provisions of section four of this act. The amounts to be assessed upon private estates as herein provided shall be assessed and collected, and shall be a lien on said estates, in the same manner and with the same effect as is provided in the case of assessments for street watering. Sec. 7. [As amended by section 5, chapter 268, acts of 1906.1 If, in the opinion of the assessors of a city or town, any land therein has received, by reason of the abate- ment of said nuisances thereon by said superintendent or by said city or town, a sjjccial benefit beyond the general advantage to all land in the city or town, then the said assessors shall' determine the value of such special benefit and shall assess the amount thereof upon said land: Provided, That no such assessment on lands contiguous and held under one ownership shall exceed one half of one per cent of the assessed valuation of said lands; and Provided, That the owner or owners shall have deducted from such assessment the amount paid and expended by them during the twelve months last preceding the date of such assessment toward abating the said nuisances on said lands, if, in the opinion of the assessors, such amount has been expended in good faith. Such assessment shall be a lien upon the land for three years from the first day of January next after the assessment has been made, and shall be collected under a warrant of the assessors to the collector of taxes of such city or town, in the manner and upon the terms and conditions and in the exercise of the powers and duties, so far as they may be applicable, prescribed by chapter thirteen of the Revised Laws relative to the collection of taxes. Real estate sold hereunder may be redeemed within the time, in the manner, and under the provisions of law, so far as they may be applicable, set forth in chapter thirteen of the Revised Laws for the redemption of land sold for taxes. A person aggrieved by such assessment may appeal to the superior court for the county in which the land lies, by entering a complaint in said court within thirty days after he has had actual notice of the assessment, which complaint shall be determined as other causes by the court without a jury. The complaint shall be heard at the first sitting of said court for trials without a jury after its entry; but the court may allow further time, or may advance the case for speedy trial, or may appoint an auditor as in other cases. The court may revise the assessment, may allow the recovery back of an amount wrongfully assessed which has been paid, may set aside, in a suit begun within three years from Uie date thereof, a collector's sale made under an erroneous assessment, may award costs to either party and may render such judgment as justice and equity require. If, in the opinion of the assessors, the owner of an estate upon which an assessment as aforesaid has been made is, by reason of age, infirmity or poverty unable to pay the assessment, they may upon application abate the same. Every city or town in ren- dering an account to the state auditor as provided for in section four of this act shall deduct from such amount as it has expended the total amount it has received for work performed under section six of this act during the term covered by the account: Pro- vided, Such work was performed under such conditions as require. reimbursement in whole or in part by the state. Sec. 8. To meet the expenses incurred under authority of this act, there shall be allowed and paid out of the treasury of the Commonwealth, during the period up to and including May first, nineteen hundred and seven, the sum of three hundred thou- .sand dollars. Of this amount seventy-five thousand dollars may be expended during the calendar year nineteen hundred and five; one hundred and fifty thousand dollars, and any unexpended balance of the previous year, may be expended during the cal- endar year nineteen hundred and six ; and seventy-five thousand dollars, and any unex- pended balance of the previous years, may be expended during the calendar year nineteen hundred and seven, up to and including May first. STATE WORK RESUMED TN MASSACHUSETTS. 35 Sec. 9. An additidiial huiu of ten thdusand dollars in each of the years nineteen hundred and five, nineteen hundred and six and nineteen hundred and seven may, in the discretion of the state superintendent, be expended by him for exjjerimenting with parasites or natural enemies for destroying said moths, and any unexpended balance of any year may be expended in the subsequent years. Sec. 10. Chapter two hundred and ten of the acts of the year eighteen hundred and ninety-one and sections one and two of chapter five hundred and forty-four of the acts of the year eighteen hundred and ninety-eight and section two of chapter fifty-seven of the acts of the year nineteen hundred and two, are hereby repealed. Sec. 11. [As amended by section 6, chapter 268, acts of 1906.] A person who will- fully resists or obstructs the superintendent or an official of a city or town, or a servant or agent duly employed by said superintendent or by any of said officials, while law- fully engaged in the execution of the purjxjses of this act, or who knowingly fails to comply with any of the rules or regulations issued by said superintendent, shall forfeit a sum not exceeding twenty-five dollars for each offence. Sec. 12. Valuations of real and personal property of the year nineteen hundred and four shall govern the provisions of this act. Sec. 13. This act shall take effect upon its passage. Approved May 8, 1905. This law is now in force, with a few minor administrative amend- ments. In the spring of 1909, following the resignation of the state superintendent, an amendment was enacted i)lacing the work in charge of the state forester. The law provides a cooperative plan for fighting the gipsy moth and brown-tail moth by which each infested city or town is required to appoint a local superintendent and to expend annually a certain amount, based on its valuation, and, after this has been done, sub- ject to the approval of the state forester, reimbursement is allowed by the State in amounts graduated according to assessed valuation. Thus the large cities are required to expend a larger amount before receiving any reimbursement from the State, and then receive a smaller percentage than the towns with small valuations and large areas of woodland, which are very expensive. to treat. Cities and towns with an assessed valuation on real and personal property of $12,500,000 or more shall, after expending $5,000 in any one year, be reimbursed 50 per cent of all further expenditures. Cities and towns where the assessed valuation ranges between $6,000,000 and $12,500,000, after expending one twenty-fifth of 1 per cent of the valuation, are reimbursed 80 per cent of all further expenditures. Cities and towns where the assessed valuation falls below $6,000,000 are required to expend one twenty-fifth of 1 per cent and are reim- bursed in full for all further expenditures. The property owner is required to clear his premises of the insects and to expend therefor not more than one-half of 1 per cent, or $5 per $1,000, of the assessed valuation. In case of failure to do this work after proper notice has been served, the premises may be treated by 36 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. the town officials and the cost, not to exceed the above amount, may be levied and collected in taxes. The whole purport of the law is to divide the burden between the property owner, the infested municipalities, and the State, and to place the entire work under state supervision in order to secure uniformity of methods and economy of expenditure. The law provided for an appropriation of $75,000 for the year 1905, $150,000 for 1906, and $75,000 for 1907. An appropriation of $10,000 a year was also made for a period of three years to provide for the expense of introducing the parasites and natural enemies of these insects from abroad and for their propagation and dissemina- tion in the infested district. The latter work was organized in co- operation with the United States Bureau of Entomology under the direction of Dr. L. O. Howard, Chief of the Bureau. On May 15, 1905, Mr. A. H. Kirkland was appointed state super- intendent by Hon. W. L. Douglas, then governor of the State. The wisdom of this appointment was soon apparent in the results secured in organizing a most difficult piece of work and in training a skilled force of men for efficient service, and the State was very fortunate in being able to procure the services of a well-trained entomologist, who brought to the work a thorough knowdedge of the conilitions to be met, high scientific attainments, and rare executive ability — a combination seldom secured. The work during the year 1905 consisted in organizing the moth forces in towns in the infested territory and sending the most expert men that could be employed by the central office into the out- side districts to determine if the gipsy moth was present. As a result of a hurried inspection it was determined that 124 towns, covering an area of 2,224 square miles, w^ere more or less infested, against 34 towns, covering an area of 359 square miles, in which the moth was known to exist in 1900, when the state work was discontinued. The gipsy moth was also found in several towns north of the Massachu- setts line in New Hampshire, to and including Portsmouth, while the colony at Providence, R. I., had increased to a considerable extent. Practically the same methods were used as those adopted when the old work was in progress, although, owing to the increased area infested and the extremely bad condition of the central district, it was necessary to abandon the idea of extermination and use all possible methods to control the insect and to prevent its further spread. The scouting operations which were carried on in the out- side infested tow^ns were, of course, done in a rather hurried manner on account of the great pressure of other work and the necessity for immediately taking active measures to destroy the moths in the badly infested towns and cities. Much effort w^as necessary in order to organize the work and secure a trained force of local men. BEGINNING OF WORK BY THE NATIONAL GOVERNMENT. 37 This large area, which included thousands of acres of badly infested woodland, was in a nuich worse condition than in 1904 and it soon became evident that heroic measures must be taken and an enor- mous amount of work done if any appreciable progress was to be made in preventing widespread injury. A single case will serve as an illustration of the loss to owners of timber caused by the gipsy moth. A tract of woodland near the Bedford and Billerica town line, belonging to the Hosmer estate, was sought by a portable saw mill operator in 1907, who offered $6,000 for the wood and timber, but, as the owners wanted $6,500, the trade was dropped. The following winter, owing to the presence of the moths in large numbers, the lot was sold for about $3,000, and immediately cut, resulting in loss to the owners of at least 50 per cent in one year. At the time the state work ceased in 1900 this prop- erty was 4 miles outside of the infested area. In 1906 the Massachusetts legislature added $150,000 to the appro- priation already made for that year and united with the other New England States in an appeal to Congress to furnish aid. The brown-tail moth was found to be present, in 1905, as far west as central Massachusetts. It also occurred in tlie southern counties m New Hampshire and along the coast, specimens having been reported from Eastport, Me., and St. John, New Brunswick. A single insect was found at Providence, R. I., during the year. BEGINNING OF WORK BY THE NATIONAL GOVERNMENT. The spread of the gipsy and brown- tail moths caused much alarm in the New England States, and in the fall of 1905 an appeal was made to Congress to assist in the work of controlling these pests. The movement was supported by delegations from Maine, where the work of the year had shown that an area of approximately 4,000 square miles was infested with the brown-tail moth and where ener- getic measures were being taken to control the insect; by New Hamp- shire, which was seriously infested with both pests; by Massachusetts, where heroic measures were being taken to control the situation; and by Rhode Island, where a serious infestation of the gipsy moth existed. On December 4, 1905, a bill was introduced by Representative Ernest W. Roberts, of Massachusetts, providing for an appropriation of $250,000, to assist in preventing the spread and securing the con- tro/ of these pests. The urgent necessity for action was forcibly brought out by a report from Dr. W. E. Britton, state entomolo- gist of Connecticut, in March, 1906, that a few egg clusters of the gipsy moth had been found in Stonington, in that State. Owing to the fact that approximately 300 square miles was thickly infested in eastern Massachusetts, ample opportunity was offered for 38 FIELD WORK AGAINST GIPSY AND BROWN-TAIL MOTHS. the larvae to be carried many miles (lurin«j the early summer, and thus the whole country was in danger of becoming infested. Later in the season $82,500 was appropriated by Congress. The work was put under the direction of Dr. L. O. Howard, Chief of the Bureau of Entomology, and Mr. D. M. Rogers, then first assistant to state superintendent Kirkland, was appointed special field agent of the Bureau in charge of the field work in New England. This appropriation became available July 1, 1906, and after a conference between the Chief of the Bureau of Entomology, the superintendent of the moth work in Massachusetts, and the special field agent of the Bureau it was decided that the most valuable results could be secured with this appropriation by at once clearing as many roadsides as possible in the thickly infested and much traveled section of Massachusetts. Arrangements were also made to prevent dissemination of the gipsy moth in the outside territory as far as the limited appropriation would allow. A force of 22 men which had been working in the infested district in Rhode Island was carried on the pay roll from July 23, 1906, to May 15, 1907, although the number at the latter date had been reduced to 9 men, so that work in that State could be continued until the state funds were available. Later in the season scouting parties were organized and a limited amount of work done in the southern parts of New Hampshire and Maine. A more detailed account of this work will be given later in this report. Owing to the severe infestation in the district around Boston (see PI. V in comparison with PI. VI), and to the fact that practically all of the main highways were being used continually during the caterpillar season by automobiles, it seemed necessary to keep the roadsides free from caterpillars if a general dissemination of the pests to distant points was to be prevented. Traffic between Boston and its suburbs, the shore resorts along the coast, and the vacation places in New Hampshire, is particularly heavy during the early sum- mer. At the time of the serious outbreak of the gipsy moth in 1890 the spread of the insect was made possi}:)le chiefly by means of teams or carriages that passed through the infested district, and these sel- dom traveled more than 20 miles in a single day. With the use of the automobile the daily travel often covers a hundred or more miles, so that the danger of spread to remote districts was greatly increased; in fact, recent inspections have shown that the spread of the insect can often be traced directly to this means of conveyance. A building was rented at Medford at a point within easy reach of the badly infested section where work was to be carried on, the neces- sary tools and supplies (figs. 8, 9) were installed, and arrangements made for actively beginning the campaign against the moths. Mr. Harry W. Vinton was selected as a special agent to take charge of Bui. S7, Bureau of Entomology, U. S. Dept. of Agriculture. Plate V. Woodland at Lexington, Mass., Completely Defoliated by the Gipsy Moth. (Original.) Bui. 87, Bureau of Entomology, U. S. Dept. of Agriculture. Plate VI. Same Woodland at Lexington, Mass., as that Shown in Plate V, the Following Year, Illustrating Beneficial Effects of Control Work. iOriginal. ) BKOINNINC Ol'' \V(»I;K \:\ 'I'll!'; NATIONAL <;< )\l';i!N M KN'I'. 39 active oixTJilioiis in I he (icid. Mr. Viiiloii Imd scrvcMl for scvci-iil years on (lieo'ipsy iiioMi woi'k when i( \v;is hein.^- condnclcd hv (lie Miissneliiisel Is slide hoard of !i{i,-i'ieulrure, iirid from his lon<^^ e.\|)eriene(', and iJioroiij^h knovvledo'(v of (J,,« pest iind the projx'r methods of treat- ment, as well as his faniiliarily with the infested region, it was possihle to he<;'in active o|)eralions withoid delay. Several trnnk roads in Melrose, Saii if any work was |)laiine(l l'"iii. s. lM|ui|iriicnl, lor rdiiilsiih; work iipilnst, Uie gii)sy iiioMi, usi'il by ciiiployccs of Mm Itiirviui of Kiilo- inoloKy. (OriRiiiul.) or has been carried out up lo the present lime in icsidenlial parls of the infested district, as the town and city ollieials, aclinic under state law, usually k(>e|) the trees in such sections fairly I'wo from infestation. The cuttin,^; out of ||i('S(> roadways is siinpl\ for the pur|)()se of prc^parino; the way for a thoroiioh and economical (reat- nient. Jt is usually n(>c(>ssary to carefully prune many of th(> tr(>es in the treated arcMi, and in some cases wlH>r<^ th(>v are of special valu(^ the cavities in hollow trees are closed with cement, covei'ed wilJi zinc, or sealed with a wooden plu<;-, so that ep()sited in such plac(>s, where it is e.\tr(>mely difliciilt to livat them. In I he s|)riiij4- the lives are handed, and hiirlaps are oflen used for this purpose. Another method which has come into favor sinc(> the gipsy moth work was resumed in Massachusetts is to apply a band 40 FIELD WORK AGAINST GIPSY AND BKOWN-TAIL MOTHS. of tanglefoot to the trunks of the trees before the eggs hatch. (See fig. 11.) Rough-bark trees should be scraped where this material is to be placed, so that the surface will be smooth enough to apply the band evenly with a wooden paddle. Care should be taken not to remove the inner bark so that the living wood will be exposed. If the tree tanglefoot can be applied evenly, no scraping should be done. This material will remain sticky for several weeks, and prevent the caterpillars from ascending, but the best practice is to draw a comb through the band as the workman walks around the tree. This brings fresh material to the surface and removes any foreign sub- stances which may have collected. The caterpillars are obliged to feed on what low growth remains on the ground and if this has been well sprayed they are soon destroyed. Aside from tlie roads Fig. 9. — Roadside where thinning operations are being carried on, .showing tools and e(|iii|auent used ia tliework. (Original.) already mentioned a considerable amount of roadside work was done in the towns of Maiden, Lynnfield, Lynn, Peabody, Wolnirn, Lex- ington, Burlington, Waltham, and Belmont, and the strips cut out during the fall of 1906 and the spring of 1907 and prepared for spring and summer treatment aggregated about 65 miles. T^ate in April and early in May, 1907, the trunks of the trees in all these strips were banded with tanglefoot to prevent the caterpillars from climbing the trees, as well as to keep such larvse as migrated from the woodland back of the strips from destroying the foliage. After the caterpillars hatched the strips were sprayed with arsenate of lead, which was used at the rate of 10 pounds to 100 gallons of water. Previous to tliis time one small and three lai'ge spraying machines operated by gasoline engines had been secured. Owing to the lim- BEGINNING OF WORK BY THE NATIONAL GOVERNMENT. 41 ited lengtli of time that the insect is in the caterpillar stage it is necessary to provide equipment so that a large area can be thor- oughly sprayed in a short time. This renders impracticable the use of hand outfits for such extensive work. The sprayers used had a tank capacity of between 500 and 600 gallons, and it was possible to treat many acres in a single day. Since the work began a number of improvements have been made in spraying outfits used, which have rendered them mqre efficient and economical. In addi- tion to the spraying the bur- lap and sticky bands on the trees were examined from time to time and the cater- pillars crushed with steel- wire brushes. In the worst infested places it was neces- sary to go over the strips daily, and even then in some instances it was almost im- possible to kill the caterpil- lars fast enough to prevent some defoliation on the back edge of the treated strips. Early in the fall of 1906 a number of the more ex- perienced men were selected and scouting operations were begun in a limited way in Maine, New Hampshire, and Connecticut. (See fig. 12, showing outfit used by gipsy moth scouts.) This work was continued until June, 1907, and a large number of towns were found infested. In the spring of 1907 it be- came evident that owino; to Fig. 10.— Employees of the Bureau of Entomology treat- ing egg clusters of the gipsy moth with creosote, using an ordinary paint brush and a brush attached to a long pole. (Original.) the discovery of so many infested towns, a larger appropriation would be necessary in order to make anything like a careful examination of the outside territory . In May, 1 907 , Congress appropriated $ 1 50,000 for the purpose of carrying on the work, this sum being available for imme- diate use. Plans were at once made to clear more roadside areas in the worst infested sections and in the fall to scout thoroughly the towns north of the known infested region. Owing to the great increase in the amount of work which was to be taken up, the territory in 42 FIELD WORK AGAINST GIPSY AND BEOWN-TAIL MOTHS. Massachusetts was divided into two sections. Mr. Vinton took charge of the crews in one of these sections, and Mr. David G. Murphy was appointed, June 17, to take charge of the crews in the other division. Mr. Murphy, hke Mr. Vinton, had had long experience in fighting the gipsy moth in Massachusetts, and had proved by his previous work with the State to be very capable in taking charge of field work. The roadside work was continued in Massachusetts during the summer and fall, and by the next spring the mileage that had been cut out had been increased twofold over that of the previous year. The strips were treated in practically the same manner as already de- scribed and much benefit resulted from this work. Special effort was made in the fall to thoroughly scout the region outside of the towns known to be infested in New Hampshire. The work was handicapped to some extont by inability to secure men with sufficient Fig. 11.— Roadside which has been cleared of brush and the trees banded witli burlap and tanglefoot. (Original.) training who were willing to take up this arduous work during the winter. The scouting, however, resulted in the discovery of 17 additional infested towns. Work of a similar character was carried on in Maine, where five more towns were found to be infested. In the spring of 190S Congress appropriated $250,000 for the work covering the fiscal year from July 1, 1908, to June 30, 1909. The work of clearing roadsides was vigorously pushed throughout the year so that by the spring of 1909, 170 additional miles of 100-foot strips had been put in good condition for summer treatment. In addition to this amount it was necessary to spray and care for 130 miles of strips that had been thinned during the previous years, so that in the summer of 1909 more than 300 miles of roadside were given careful attention, which undoubtedly prevented many new colonies BEGINNING OF WORK BY THE NATIONAL GOVERNMENT, 43 from becoming established. Over 200 miles of roadway, not yet cut out, which was more or loss infested, was sprayed, and this served to further decrease the (hxnger of dissemination. (See figs. 1 3 and- 1 4. ) Late in the summer of 1908 plans were made to carry on an extensive inspection of the outside territory in New Hampshire and Maine. Owing to the size of the territory to be covered in New Hampshire it was divided into two sections, and A^Ii\ Irving L. Bailey was selected to take charge of the western section and Mr. Henry L. Mclntyre was placed in charge of the work in the eastern section. Both were men of extended experience in gipsy-moth work in the field, Mr. Bailey having been employed as an inspector when the insect was being fought by the Massachusetts state board of agri- culture, and Mr. Mclntyre having had much practical experience in town work for controlling the moths and later in the field work which was being carried on by this ofhce. About November 1, several crews of tlio most expert men were sent to New Hampshire and from time to time the force was increased un- til over 100 men were employed in scouting work in the various towns. Practically all of the territory south of Lake Winnepesau- kee and a double tier of towns west of the Mer- Fig. 12.— Gipsy moth scout's outfit, consisting of climljing irons, rimac River were ex- ™i™''. cleaning knife, can of creosote, and brush. (Original.) amined and most of them were found to be more or less infested. In this work all of the roadways, orchards, and private property were inspected; in fact, all trees were examined except the large forest areas. Several crews were detailed to scout along the main high- ways north of Lake Winnepesaukee, as these form the main routes of travel for summer tourists to the White Mountains. The principal roads from Ossipee to the mountains as far as Bethlehem and Bretton Woods were carefully inspected; also along the roads on the west side of the mountains through the Pemigewasset. Valley. No egg clusters were found north of Ossipee on the eastern or above Mere- dith on the western roads. While this work was being carried on several crews were engaged in making examinations of the territory surrounding the known infested towns in Maine. This region was found to be in much more satisfactory condition than during the previous year. All work that seemed necessary was done in Connec- ticut and the condition of this territory showed marked improvement. 44 FIELD WOEK AGAINST GIPSY AND BROWN-TAIL MOTHS. The great danger throughout the entire campaign in fighting the gipsy moth has been the existence of large woodland colonies and it has been impossible for either this office, the States, or the individual property owners to keep the* moths reduced in territory of this character on account of the vast expense involved. In eastern Massachusetts and southern New Hampshire there are large areas of forest land which are covered with an inferior growth of trees and which are badly infested. In most cases the cost of cleaning up such areas and stamping out tlie bad colonies would amount to more than the value of the property. This being the case the main attempt has been to keep the roadways through forest areas free from the young caterpillars and to prevent to as great an extent as possible any further spread of the pest. (See PI. VII.) Fig. 13.— Roadsides badly infested by the gipsy moth. (Original.) During February, 1009, Congress appropriated $300,000 to pro- vide for the continuation of the work. This sum was available for the fiscal year beginning July 1, 1909. Since that time work on roadsides has been continued in Massachusetts and up to January 1, 1910, nearly 150 miles of 100-foot strips have been cut out and pre- pared for spring and summer treatment. The roadways cut out up to January 1, 1910, aggregate 450 miles of strips. (See fig. 15.) During the period since the government work began about $300,000 has been expended in Massachusetts for labor and transportation of men. This does not include the amounts expended for salaries, rent, tools, equipment, insecticides, supplies, and the expenses that have been paid by the Government for the maintenance of the Gipsy Moth Parasite Laboratory. Late in October, 1909, 16 scouting crews of 5 men each were sent to the northern portion of the infested district in New Hampshire Bui. 87, Bureau of Entomology, U. S. Dept. of Agriculture. Plate VII. o < D m S 2 3^ o K^ ^^ -n Pi2. ^ B^r. o o C 'y. ;£ u P 2.A > o iS. z u p-O h- , o m oo-^ > S'*^ '^ :d S'a ^ o > D ^ > fo 2; ^ m ^=^ CO o f»3i; H o ^ -5' O S's •^^ 1 3-S" ^ S'^'g O 33 ro w.r'c' X ri Bs- = O z > § p 5"5 .^ Krr^ ^ m •5 !5 3 m o H «33 O -n o ^ — •S^f 3J m O ^ ro o p S > ^a a > K^ z H » £.a H p-l^ o — O rn '^?r