Digitized by the Internet Archive in 2011 with funding from LYRASIS members and Sloan Foundation http://www.archive.org/details/reportofstateent434conn ^W ! .! CON'N Bulletin 434 June, 1940 5^ ' Connecticut State Entomologist thirty-ninth report 1939 R. B. FRIEND, PH.D. State Entomologist Cnnn^cttott ^grtntltural Experiment ^lattmt CONTENTS Page Wilton Everett Britton 215 Introduction 222 Insect Record for 1939 223 Conference of Connecticut Entomologists 225 Inspection of Nurseries, 1939 227 Number and Size of Nurseries 227 Connecticut Nursery Firms Certified in 1939 228 Other Kinds of Certificates Issued 235 Inspection of Imported Nursery Stock 236 Results of Inspection 236 Inspection of Apiaries, 1939 237 Statistics of Inspection 238 Financial Statement 239 Registration of Bees 239 Report on Control op the Gypsy Moth. 1938-1939 239 New Equipment 240 Control Operations 240 Work Performed by State Men 240 Work Performed by C.C.C. Men 241 WPA Work Performed 241 Scouting for Brown-Tail Moth 242 Financial Statement 242 Statistics of Infestations 243 The Japanese Beetle, 1939 248 Quarantine Activities 248 Scouting 248 Inspection and Certification 248 Control Activities 249 Mosquito Control Work in Connecticut, 1939 251 Rodent Control 254 Mouse Control 254 Pine Mouse Control 255 Woodchuck Control 255 Survey of Mammal Damage in Nurseries 257 Mouse Injury 257 Deer Injury 258 Report on Parasite Work for 1939 258 Oriental Fruit Moth Parasites 258 Japanese Beetle Parasites 259 Tests of Apple Sprays , 260 Continued Experiments on Control of the Apple Maggot 264 Continued Study of Stickers for Standard Spray Mixtures 269 Experiments with Manganese Sulfate as Safener for Lime Sulfur-Lead Arsenate Spray Mixtures 272 Corn Borer Insecticide Investigations 273 Effect of Corn Borers on Potato Yield 275 Page Biology and Control of the Potato Flea Beetle 277 Seasonal Life History 277 Life History Studies 277 Control 277 Summary 282 Survey of Wireworm Injury to Potatoes 283 Control of Squash Insects 285 Further Observations of the Effect of Salt Water Spr.w on Foliage . . . 287 Notes on the Smaller European Elm Bark Beetle, Scolylus muUistrialus Marsham 293 Life Cycle 295 Habits 296 Developmental Stages *. 302 Flight and Wind Dispersion 305 Parasites and Predators 306 Survival of Larvae at Low Temperatures 307 Artificial Control 307 Summary 309 Miscellaneous Insect Notes 311 The Crazy Ant in Cormecticut 311 Dermestid Larvae in Composition Board 312 The House Cricket, Gryllus domesticus Linn 312 Notes on Asiatic Garden Beetle Damage in a Field of Sweet Corn 313 Results of Trapping Rose Chafers 314 The European Earwig 314 Bark Beetle Damage to Plantation Pine 315 Clover Mite in Dwellings 317 Calomyderus selarius Roelofs in Connecticut 318 Publications, 1939 318 Summary of Office and Inspection Work 320 Index 321 WILTON EVERETT BRITTON September 18, 1868— February 15, 1939 State Entomologist, July 1, 1901— February 15, 1939 WILTON EVERETT BRITTON Roger B. Friend "rkOCTOR Wilton Everett Britton, State Entomologist of Connecticut and Entomologist of the Agricultural Experiment Station at New Haven, died February 15, 1939, in his seventy-first year. He had been a member of the staff of the Agricultural Experiment Station since 1894 and State Entomologist since the office was established in 1901. During his long and useful career he exemplified that devotion to his profession and to the welfare of his State that characterizes a public servant of the highest calibre. Dr. Britton descended from a line of New England ancestors going back to James Britton who, at the age of 27, arrived in America on the Increase April 15, 1635. Probably he came from London, and he lived for a time in Charlestown, Massachusetts. The succeeding generations of the family, dwelhng in eastern Massachusetts, southern Maine, and southern New Hampshire, were presumably typical of that class whicli formed the backbone of the population, a race of farmers, sailors, mechan- ics, small merchants, and, when wars were afoot, soldiers. Dr. Britton's father, Benjamin Howard Britton, was born at North Easton, Massachu- setts, in 1833 and died at Gilsum, New Hampshire, in 1899. In 1861 he married Emily Eliza Wright, whose great grandfather had come from Hartford, Connecticut, and died at Keene, New Hampsliire, in 1812. Dr. Britton was born at Marlboro, Massachusetts, September 18, 1868. His family moved to a farm in Gilsum, New Hampshire. There, in a distinctly rural environment, the impress of which lasted throughout his life. Dr. Britton spent his early years. He attended the local schools and worked on the farm, raising the crops, caring for livestock, lumbering, making maple sugar, etc. Life was a bit rigorous, but conducive to integ- rity, industry, frugality, and independence of thought and action. He enjoyed it. Later he attended the New Hampshire College of Agriculture and Mechanic Arts at Hanover (now the University of New Hampshire at Durham), from which he received the degree of Bachelor of Science in 1893. If later performance is any criterion, he must have been a good student. The year following graduation was spent at Cornell University studying under L. H. Bailey. Apparently at that time Dr. Britton's main interests lay in the field of horticulture. In 1894 the opportunity came to obtain a position as horticulturist at the Connecticut Agricultural Experiment Station at New Haven. Both student and professor evidently believed this position offered great promise professionally, for Dr. Britton once told the writer that Bailey advised him to take the job even if he received no salary. The advice was followed, although salary there was — fifty dollars a month. This inchnation to disregard remuneration when offered an opportunity to work in his field was quite characteristic. While at the Agricultural Experiment Station he continued graduate study in the Department of Botany at Yale Univer- sity and received the degree of Doctor of Philosophy from that institution in 1903. 216 Connecticut Experiment Station Bulletin 434 During his tenure as horticulturist, Dr. Britton collaborated with the Station chemist, Dr. E. H. Jenkins, in fertilizer investigations, worked with "forcing-house" crops, conducted experiments in grafting nut trees, and began his entomological career. The reports of the Experiment Station during this period indicate that his work was carefully done and of such high quality that the confidence of his superiors became firmly established. Dr. Britton's interest in entomology dates back to his boyhood days. The economic aspect of the science was early impressed on him by long hours spent in the hot summer sun knocking Colorado potato beetles off the plants into a can. While at college he made a collection of insects and built a fine cabinet with eighteen glass-topped drawers to house it. This was the foundation of the present collection at the Experiment Station, and the cabinet is still in use. At this time he also wrote an article entitled "The Horn Fly", which was published in the New Hampshire College Monthly in 1893. While working in horticulture, his attention was drawn to insect pests of cultivated plants and he considered them well worth investigating. In the report of the Experiment Station for the year 1894, a short article entitled "Notes on Some Leaf Miners" (pp. 143-146) bears his signature. This describes the life cycle and habits of Odontocera dorsalis Loew {Cerodontha femoralis Meigen), the habits of which had been unknown up to that time, on corn, and Phytomyza aquilegiae Hardy, not previously known to have occurred in this country, on columbine. At this time the Station mycologist. Dr. Sturgis, was interested in insect pests and con- tributed articles on the subject to the Station reports. Dr. Britton gradually swung to entomology, emphasizing this phase of his work increasingly each year. His horticultural and botanical training stood him in good stead, and he never fully relinquished his interest in these fields. Even during the latter part of his life he remained the Station authority on the identity of native plants and horticultural varieties. In the Station Report for 1895, he pubhshed short articles on several insects, including one on the greenhouse whitefly, and, in collaboration with Sturgis, an article on the San Jose scale. These two last were the first of a number of contributions to our knowledge of whiteflies and scale insects. Also in 1895 appeared Station Bulletin 121 on the elm leaf beetle, by Britton, Sturgis, Jenkins and Johnson. Dr. Britton later became a widely known authority on insects affecting trees. In the Report for 1896 the section entitled "Insect Notes" was written by Dr. Britton, who had apparently by this time assumed the entomological work of the Station. The Report for the following year states: "The necessary Entomological work of the Station, such as the determination of species of insects sent for identification, experiments in the destruction of insect pests, and the efficiency of various insecticides, has also been done by Mr. Britton". In this Report, and those of the next few years, the work of the horticulturist is briefly noted by the Board of Control under the title of "Horticultural and Entomological Work". Apparently the die was cast, and Dr. Britton decided to devote much of his time to entomology. From 1897 to 1901, while still carrying on horticultural investigations. Dr. Britton gave increasing attention to entomological problems. He published bulletins and short articles on fruit, garden, greenliouse, and shade tree pests. The nursery inspection work began in 1898 when Wilton Everett Britton 217 eleven nui'series were examined and eight certificates issued. Other states were demanding inspection certificates on nursery stock shipped into their territory, so inspection of Connecticut nurseries became necessary. At this time the San Jose scale was a notorious pest of fruit trees, and in 1899 the Station Board of Control formally adopted regulations regarding nursery inspection. In the Report of the Station for 1900 the following statement occurs: "More than fifty insects have been sent in by farmers for identification. These have been in every case named and all available information given as to their habits and, where necessary, as to the best way of destroying them The facilities of the department have been greatly increased by the addition of a microscope and accessories and by fitting up a new office and laboratory for Mr. Britton.'' In 1900 appeared Bulletin 131, "Protection of Shade Trees", by Jenkins, Britton, Graves, and Blake, a report by the committee to the Mayor of New Haven. At the January Session for 1901, the General Assembly passed "An Act Concerning Insect Pests" which required the Board of Control of the Agricultural Experiment Station to appoint a State Entomologist to serve during the pleasure of the Board and to be responsible to it. He was to receive no compensation other than his salary as a member of the Station staff. In July, 1901, Dr. Britton was appointed and received the title of Entomologist of the Station as well as that of State Entomologist, although he continued his horticultural work for several years. Apparently this Act of the General Assembly was the result of the desire of nurserymen and orchardists to be protected against insect pests. The Connecticut Pomological Society was particularly active in the matter. The Act provided for general duties of the State Entomologist, including nursery inspection, inspection of other premises, investigations, publication of bulletins, etc., and an appropriation of $3,000 a year for two years. One of Dr. Britton's first purchases was "an excellent photograpiiic outfit". This camera is now used by the Entomology Department for making enlargements, and the lens is still used for regular photographic work. The State Entomologist undertook his duties with energetic enthu- siasm. He not only met various situations as they arose, but, prophetically, anticipated future problems and was prepared for emergencies. The demands on his office increased as time went on, and the high quality of service rendered the people of the State engendered confidence in the work. With the increase of personnel to the stafi" and a multiplication of tasks, including research, control, quarantine, publication, and the mani- fold activities involved in keeping track of insect pests and informing the people of the State about them. Dr. Britton's work gradually shifted in emphasis from research to administration. In Connecticut the State Entomologist is also Entomologist of the Agricultural Experiment Station, and hence directs the research and also administers all regulatory phases of entomology, an ideal arrangement for a small state. Some conception of the work carried on by the Entomologist and his staff may be obtained by briefly reviewing the succession of insect pests which received attention during Dr. Britton's term of office. The presence of these pests necessitated a series of investigations of their life cycles, habits, relations to the environment, economic importance, and frequently large scale control operations and the enforcement of quarantines and other regulations. 218 Connecticut Experiment Station Bulletin 434 During the first few years, tlie San Jos6 scale was a major problem in orchards and nurseries. In 1903 the salt marsh mosquito nuisance received some attention, and the investigations conducted gradually led to the organization of a state-wide marsh drainage program and the maintenance of such areas free of mosquito breeding centers. The inhab- itants of shore towns have benefited materially by this work. In 1906 the gypsy moth was discovered at Stonington, and vigorous measures were undertaken to suppress it. Gypsy moth suppression is an important part of the work of the Entomologist today. The remarkably small amount of injury by this insect to the forests of the State reflects the efficiency of the gypsy moth control program. In 1909 the General Assembly, as a result of agitation by the Connecticut Beekeepers' Association, passed an apiary inspection law and placed the inspection service under the State Entomologist. European foul brood was then the most important disease of bees in the State, and the apiary inspection was an attempt to reduce the infection of this as well as other diseases. In August, 1915, Diprion simile, a European sawfly injurious to pines, was discovered in New Haven, its first appearance in the United States. Its biology was investigated at once and control measures developed. The laws pertaining to gypsy moth control and mosquito elimination first became eff'ective in 1915. In 1918 the Oriental fruit moth was found in Connecticut. This insect became definitely injurious to the peach crop in 1923 and since then has caused tremendous loss to the peach industry. Efforts to develop a practical means of controlling it have involved a long series of insecticide and parasite investigations. The present work in the biological control of insect pests carried out at the Experiment Station is an outgrowth of fruit moth investigations. Two interesting fruit tree pests were discovered in the State in 1920, the European red mite and the apple and thorn skeletonizer, both im- migrants from Europe. The red mite is still seriously injurious to apple and pear orchards unless artificially controlled and has been a subject of intense study. The skeletonizer was very abundant for a few years but is not common in orchards at present. The impetus to the study of insects affecting lawns and similar grass- lands was furnished by the discovery of the Asiatic beetle in the western part of New Haven in 1922. This was the first time it had been found in the United States. A vigorous attempt to eradicate the insect failed, but in the course of the next few years suitable control measures were developed. In 1923 the European corn borer was found in Groton and Niantic. Suppressive measures were undertaken in cooperation with the Federal Bureau of Entomology, and quarantine fines were drawn. Although the dispersion of the insect was retarded for a few years, the entire State has since become well infested. Laws relating to the destruction of borer- containing material were enacted and are still in force. At present insect i- cidal control measures are being developed. Several other pests of more or less importance have appeared in the State since the corn borer arrived. In 1924 the birch leaf-mining sawfly, of European origin, was discovered, the first definite record for the country, although injured birch leaves had been noticed the previous year. A study of its biology, economic importance, and control was undertaken Wilton Everett Britton 219 with the result that ornamental birches can be protected. The Japanese beetle arrived in 1926. In spite of the enforcement of federal and state quarantine regulations, the insect spread over the State in a few years, although at present it is injuriously abundant in only a few towns and cities. Particular attention is being given to the parasites and diseases of this notorious pest. In 1929 the Mexican bean beetle was found in south- western Connecticut, and two years later it was everywhere abundant. Insecticidal and cultural control methods were soon found which were applicable to Connecticut conditions. The Dutch elm disease had reached Connecticut in 1933, and investigation of the elm bark beetles transmitting this disease was begmi at once. The felted beech scale and the European spruce sawfly, both potentially serious pests of forest trees, were found in the State in 1934 and 1935 respectively. Neither has caused much injury to date, but both are being watched. During all this period the insect collection of the Station was steadily built up. It now contains about 7,000 species of Connecticut insects, the total specimens numbering over 100,000. This collection is of inestimable value to the work of the Entomology Department and is frequently used by entomologists from all parts of the country. Dr. Britton's professional interest in entomological work involved several fields of activity. From 1901 to 1905 he lectured in forest ento- mology at the School of Forestry of Yale University. From 1910 to 1929 he was Associate Editor of the Journal of Economic Entomology. In 1911 appeared the first of a series of taxonomic bulletins entitled "Guide to the Insects of Connecticut", prepared under his direction and published by the Connecticut Geological and Natural History Survey. This first volume contained "Part I, General Introduction" by Dr. Britton, and "Part II, Euplexoptera and Orthoptera of Connecticut" by B. H. Walden, a member of his staff". "Part III, The Hymenoptera or Wasp-like Insects of Connecticut", which appeared in 1916, was compiled by H. L. Viereck, a member of his staff, in collaboration with other authors. Dr. Britton wrote the sections on Coccidae and Aleyrodidae in "Part IV, The Hemiptera or Sucking Insects of Connecticut", published in 1923. Another staff" member, Dr. Philip Garman, wrote "Part V, The Odonata or Dragonflies of Connecticut". Dr. Britton wrote the "Check-List of the Insects of Connecticut", pubUshed in 1920 as Bulletin 31 of the Survey, and its "First Supplement", published in 1938 as Bulletin 60. The latter bulletin also contained the "Check-List of the Spiders of Connecticut" by another of the staff". Dr. B. J. Kaston. At present a continuation of this series, the Diptera, is being prepared for publication. From 1925 until his death, Dr. Britton was Superintendent of the Survey, part of the time, during an economic stringency when the General Assembly efiminated the appropri- ation for its support, serving without salary. Dr. Britton served on the Board of Governors of the Crop Protection Institute from 1922 to 1924. He was for many years a member of the Eastern Plant Board and its Chairman in 1936. Since the formation of the Connecticut Tree Protection Examining Board in 1919 he acted as chairman until his death. The Board held institutes for the instruction of tree workers for a few years, and this led to the formation of the Con- necticut Tree Protective Association in 1922. In 1924 a Shade Tree Confer- 220 Connecticut Experiment Station Bulletin 434 ence, with Dr. Britton as Chairman, was held in Stamford, Connecticut. This soon became national in scope, and the fifth conference in Brooklyn, N. Y., in 1929 became the Fifth National Shade Tree Conference. For many years Dr. Britton also served on the National Malaria Committee. By his associates in science and in agricultural work, Dr. Britton was highly esteemed. He was a member of the American Association of Economic Entomologists and its president in 1909, a fellow of the American Association for the Advancement of Science and of the Entomological Society of America, a member of the Connecticut Botanical Society, Sigma Xi and Phi Kappa Phi. In 1930 the University of New Hampshire con- ferred upon him the honorary degree of Doctor of Science. In 1936 the Connecticut State College awarded him Honorary Recognition as a leader in agriculture and rural life. He belonged to many agricultural organiza- tions in the State. Dr. Britton was interested in civic affairs and an ardent patriot. He was the first president of the Edgewood Civic Association, in 1908, and again held this office in 1920. He organized and served as director and president of the Donald G. Mitchell Library in Westville. From 1912 on he was a director of the Young Men's Institute of New Haven and from 1925 to 1932 he served on the Board of Directors of the New Haven Public Library. From April, 1917, to December, 1920, he was a member of the Second .Company, Governor's Foot Guard. During the World War he was chairman of the Committee on Food of the New Haven War Bureau. The list of Dr. Britton's publications is too long to include here. He wrote about 541 scientific bulletins and shorter articles on horticultural, botanical and entomological subjects, and over 41 other articles on various matters. Among his outstanding contributions to entomology, the series "Guide to the Insects of Connecticut" has been mentioned. His annual reports of the State Entomologist, 38 in number, are unsurpassed in both text and illustration. They cover all phases of work in economic ento- mology in the State. He wrote the "Plant Pest Handbook, I. Insects", an outstanding experiment station publication. A facile writer, his pubhca- tions exhibit meticulous care in preparation. A man's accomplishments depend on his personal qualities. Dr. Britton adhered to sound principles in his personal affairs and his relations to members of his staff and other associates in his profession, as well as to his community. Although inherently conservative and personally rigidly adherent to an ethical code which demanded honesty, integrity and candor, he was at the same time liberal in his judgment, tolerant in his decisions, disinterested and generous. To the members of his staff he was always stimulating. Interested in every phase of their activities and demanding intelligent application to the task at hand, faithful performance, loyalty, and devotion to the public welfare, at the same time he neither interfered unduly in their work nor evaded responsibility for their acts. He was excessively careful in giving them credit for whatever they accom- pHshed. Those outside the Experiment Station with whom the State Entomologist cooperated in many phases of entomological work found him an ideal associate, and the community in which he lived benefited by his presence. In spite of his manifold tasks and remarkable productivity, he took the oscillations of fortune philosophically, confident of the outcome, * Wilton Everett Britton 221 unperturbed, saved from fretfulness by a serene disposition and a sense of humor. Dr. Britton became ill in the summer of 1938 and before winter it was obvious that an operation would be necessary. Although he reaUzed the seriousress of his condition, he calmly kept at his work while following the advice of his physician. The operation failed to clear up the trouble. Ultimately, unable to care for himself, he went to a hospital in New Haven. The members of his staff kept him in touch with affairs at his office, and his interest in the work continued as long as he was able to carry on a conversation. Although he must have suffered intensely at times, he never complained of physical discomfort. His own personal future did not appear to concern him greatly; the inevitable was beyond his control. Gradually weakening, he finally sank into a coma and died. He was buried in Surry, New Hampshire, in the grave beside his wife. Bertha Madeline Perkins, whom he had married in 1895 and who died in 1938. There were no children. D CONNECTICUT STATE ENTOMOLOGIST THIRTY-NINTH REPORT 1939 R. B. Friend INTRODUCTION kOCTOR Wilton Everett Britton, State Entomologist of Connecticut since the office was established in 1901, died February 15, 1939. A brief biographical sketch of Dr. Britton is included in this report. The staff was augmented this year by the appointment of Raimon L. Beard, who received the degree of Doctor of Philosophy from Yale University in June. Doctor Beard has been a temporary employe of the Station for several summers, giving particular attention to the squash bug. He will continue to work with vegetable crop pests. In its research work the staff has continued to devote most of its time to a group of major insect pests affecting fruit orchards, vegetable crops, grasslands, and shade and forest trees. The biology of these pests has been studied and efficient means of controlling them sought by the use of insecticides, parasites, cultural practices, etc. Among those investi- gated, particular attention was given to the apple maggot, European red mite. Oriental fruit moth, red-banded leaf roller, Japanese beetle, a native scarabaeid (Cyclocephala horealis) affecting lawns, chinch bug, European corn borer, squash pests, potato flea beetle, white pine weevil, European pine shoot moth, European elm bark beetle, and rodents. The progress made in these investigations is indicated in the following pages of this Report and in the bulletins and scientific papers published by the staff, a list of which is to be found at the end of this bulletin. The cooperation of the Federal Bureau of Entomology and Plant Quarantine in various ento- mological problems, and of the Federal Bureau of Biological Survey in rodent control, is gratefully acknowledged. In addition to research work, members of the staff are constantly requested by citizens of the State to investigate pest outbreaks and injury on farms, in home vegetable and flower gardens, in forests and on estates, in homes and public buildings, etc. These requests, which involve any- thing from rabbits, rats, and mice to insects and organisms in drinking water, receive immediate attention either by mail or personal visits, and information on control is given the persons concerned. Most of the pests are insects affecting plants, household insects and termites. The effect of the hurricane on trees and shrubs along the shore of the sound has been investigated and the results summarized in this Report. The State Entomologist is responsible for the inspection of nurseries and apiaries, the enforcement of insect quarantines, and the control of the gypsy moth, all of which are reported in the following pages. Mosquito Insect Record for 1939 223 control on salt marshes is now carried out under the direction of a Board of Mosquito Control of which the Director of this Station is at present Chairman. This work is also reviewed. INSECT RECORD FOR 1939 /CERTAIN species of insect pests were unusually abundant and injurious in ^ 1939 or deserve mention for some other reason. One of the most important features of the season was the great increase in abundance and injuriousness of the Japanese beetle (Popillia japonica Newm.). This insect attained the status of a serious pest of ornamental trees and shrubs and of grapevines in parts of Fairfield, Hartford and New Haven counties, and the larvae injured grassland in these as well as in some other parts of the State. In the vicinity of Windsor, beetles were observed feeding on tobacco leaves. The gypsy moth (Porthetria dispar L.) increased in abundance in the Granby-Simsbury area; trees on 2500 to 3000 acres were completely defoliated. A small but heavy infestation, in which trees on about one acre were stripped of leaves, was found on the Southbury-Roxbury line. The fall webworm {Hyphanlria ciinea Drury) was quite abundant over most of the State, perhaps more so in Fairfield and New Haven counties than elsewhere. The European elm bark beetle (Scolytus miiHistriatus Marsh.) was more abundant than usual in New Haven County and has spread eastward somewhat into the towns along the Connecticut River south of Hartford. The locust leaf miner {Chalepiis dorsalis Tlmnb.) was quite abundant in Middlesex and New London counties and badly injured the foliage of many black locust trees. The walnut caterpillar {Dataua infegerrima G. & R.) stripped the foliage from many black walnut, butternut, and shagbark hickory trees late in the summer. In northwestern Connecticut the elm flea beetle {Altica ulmi Woods) has been abundant during the last two years. In 1939 the foliage of some elms in this region was severely injured. The elm spanworm (Ennomos subsignarius Hiibn.) outbreak in Monroe, where trees on about 250 acres of forest were defoliated in 1938, declined noticeably in 1939. The forest tent caterpillar {Malacosoma disstria Hiibn.) was less abundant in western Connecticut than in previous years. The outbreak appears to be definitely declining. The first generation of the Oriental fruit moth (Grapholitha molesta Busck) was unusually abundant in June in Fairfield and New Haven counties and was quite abundant throughout the State. Egg parasitism by Trichogramma, as well as larval parasitism, was high. The second generation was less numerous and the fruit in general was less heavily infested than in 1938. The plum curculio {Conotrachelus nenuphar Hbst.) was seriously injurious to apples, peaches, and cherries in New" Haven County. This insect was more conspicuous than usual. 224 Connecticul Experiment Station Bulletin 434 The apple maggot {Rhagoletis pomonella Walsh) was unusually abundant over much of the State late in the summer. The European red mite (Paratetranychus pilosus C. & F.), another pest of apples, was less injurious than usual in New Haven County. The rose chafer {Macrodactylus suhspinosus Fabr.), which is a rather omnivorous feeder, injured peach trees and Siberian elms in New Haven and Middlesex counties. The rosy apple aphid (Amiraphis roseus Baker) was not as injurious as usual in orchards, because of an unfavorable season. The European corn borer (Pyrausta nuhilalis Hiibn.) reached the highest population density ever recorded in Connecticut. In early sweet corn in New Haven County the number of first generation larvae averaged about 20 per cornstalk. Many fields of sweet corn were a total failure. Another corn pest, the corn ear worm (Heliothis obsoleta Fabr.) was abun- dant late in the summer in southern Connecticut. About seven acres of early sweet corn in Southbury were severely damaged by a species of thrips. In East Haven a 12-acre field of corn suffered severely from army- worms (Cirphis unipunda Haw.). The cabbage maggot {Hylemyia brassicae Bouche) was abundant, the injury in untreated fields of cabbage, cauliflower and broccoli ranging up to an almost total loss. Early potato fields were severely injured by the flea beetle (Epitrix cucumeris Harr.) and the aphid (Macrosiphum solanifolii Ashm.). The aphid was particularly injurious in Fairfield County, and, on late potatoes, in the Connecticut River Valley. The potato leafhopper (Empoasca fabae Harr.) was more abundant than in 1938 and tipburn was common. Squash and melons suffered from the attack of the striped cucumber beetle (Diabrotica vittata Fabr.), and the squash borer (Melittia satyrini- formis Hiibn.) was locally injurious to squash. | The spinach leaf miner (Pegomyia hyoscyami Panz.) severely injured early beets in some fields. The Mexican bean beetle {Epilachna varivestris Muls.) was not very serious throughout the State, although a few fields were heavily infested. The wireworm {Limoniiis agonus Say) was more abundant in tobacco fields than in 1938, but less abundant in potato fields. The European earwig {Forficula auricular ia L.) was first found in Connecticut in the western part of New Haven in 1938. During 1939 it was discovered in several adjacent yards. The harlequin cabbage bug (Murgantia histrionica Hahn) was found at Mt. Carmel where three specimens were collected. This is the first record of this southern pest in Connecticut since 1910. Chinch bugs {Blissus hirtus Montcl.) were quite injurious to lawns late in the summer. The dry weather apparently favored their increase. The Oriental beetle (Anomala orientalis Waterhouse) caused the usual amount of injury to untreated lawns in the towns of Greenwich, Stamford and New Haven. Conference of Connecticut Entomologists 225 The Asiatic garden beetle (Autoserica caslanea Arr.) was somewhat more abmidant in grasslands in southwestern Connecticut than usual. A field of corn in Westport was badly injured. During the year the office received, by mail or messenger, 568 speci- mens about which information was requested. They have been grouped in economic categories and are listed below: Specimens Receive'd — 1939 Fruit pests 35 Field, vegetable, and truck crop pests 24 Forest and shade tree pests 169 Pests of shrubs and vines 24 Flower and greenhouse pests 34 Household and stored food products pests 78 Timber and wood products pests 61 Soil and grassland inhabiting pests 61 Insects annoying man and domesticated animals 16 Parasitic and predaceous insects 17 Miscellaneous 49 568 This list does not in any way indicate the economic significance of the groups of pests, but does reflect the importance of a part of the work of the Department and the value of its collection of Connecticut insects, to which specimens may be referred for identification. Termites (or mate- rials injured by them) head the list of insects, with 38 specimens received. Termites are very mjurious to houses and other wooden structures and the public's interest in them is keen. The next on the list is the cicada killer, a wasp which preys on cicadas, 16 specimens. The burrows of this large, beautiful insect are very conspicuous in lawns in the late summer. It is an interesting species, but not a serious pest. The carpenter ant, often mistaken by the public for a termite, holds third place with 11 specimens received. This insect is injurious to structural wood and to trees. Eight specimens of each of the following were received: fleas, Oriental beetle grubs, and black carpet beetles. Fleas are pests of both man and his pets, the dog and cat, and the pets are usually responsible for infestations. Oriental beetle grubs kill lawn grass. The carpet beetle injures woolen clothing, rugs, etc. Five or six specimens of each of the following arrived: the plum curcuHo, a pest of fruit; the elm flea beetle; the hickory tussock caterpillar; the rose chafer, an omnivorous feeder on foliage and flowers; the German roach, a household pest; the Indian meal moth, a pest of cereals, flour, etc.; and the Chinese praying mantid, a very large insect which preys upon grasshoppers, caterpillars, etc, CONFERENCE OF CONNECTICUT ENTOMOLOGISTS A T THE invitation of Professor J. A. Manter, who made all arrangements for -^ the meeting, the sixteenth annual conference of Connecticut entomolo- gists was held at the Community House, University of Connecticut, Storrs, on Friday, October 27, 1939. Doctor R. B. Friend was appointed chair- man and 90 persons were present. Luncheon was served at the university grill. Unfortunately President Jorgensen could not be present, but Professor H. D. Newton, Dean of the Department of Arts and Sciences, welcomed the group on behalf of the University. Mr. A. F, Burgess was 226 Connecticut Experiment Station Bulletin 434 unable to attend and Mr. S. S. Grossman from his office took his place. The program was arranged in three sections: the first, a discussion of the European corn borer, led by Mr. Neely Turner; the second, a con- sideration of the Japanese beetle, led by Mr. J. P. Johnson, and the third on the gypsy moth with Mr. John T. Ashworth leading. The program planned was as follows: Greeting, President A. N. Jorgensen, Storrs, Conn. The European Corn Borer The Status of the Insect in Connecticut. Neely Turner, New Haven, Conn. Experiments with Dust Insecticides in 1939. C. H. Batchelder, New Haven, Conn. Biological Strains of the European Corn Borer. K. D. Arbuthnot, New Haven, Conn. Dr. W. E. Britton. E. P. Felt, Stamford, Conn. The Japanese Beetle The Status of the Insect in Connecticut. J. P. Johnson, New Haven, Conn. Nematode Parasites of the Japanese Beetle. H. B. Girth, White Horse, N. J. Bacterial Diseases of the Japanese Beetle. C. H. Hadley, Moorestown, N. J. Moving Pictures of Insect Life. J. A. Manter, Storrs, Conn. Connecticut Wildlife Problems. R. P. Hunter, Hartford, Conn. The Gypsy Moth The Gypsy Moth Problem in Connecticut. J. T. Ashworth, Danielson, Conn. Federal Gypsy Moth Control Work. A. F. Burgess, Greenfield, Mass. The Parasites of the Gypsy Moth. R. C. Brown, New Haven, Conn. ^ Inspection of Nurseries 227 INSPECTION OF NURSERIES, 1939 M. P. Zappe 'THE ANNUAL inspection of nurseries started on July 1, 1939, as required by Section 2136 of the General Statutes. The writer, assisted by Messrs. A. F. Clark, W. T. Rowe and R. J. Walker, inspected all the larger nurseries during the months of July and August. The smaller ones were inspected during September, and all regular work was completed by the end of that month. Several of the nm'series were inspected a second time to check on the eradication of pests. As a whole the nurseries were in better condition than in 1938. The business had improved slightly, and consequently nurserymen took a little better care of their stock. A few nurseries, however, are still some- what neglected. Altogether, 96 different insect pests and 52 plant diseases were found in nurseries in 1939, most of them, however, of minor or no importance. San Jose scale is very scarce at the present time. Spruce gall aphids were much less abundant than usual, especially in the hurricane area. European pine shoot moth was a little less abundant than in 1938. Pine leaf scale, on the contrary, was much more prevalent than last year. Poplar canker is becoming less abundant, perhaps because some of the nurseries have ceased growing Lombardy poplars. The presence of "X" disease of peach in Connecticut has made necessary stringent regulations for the growing of peach nursery stock. Nurserymen growing peach trees have received copies of these regulations. Some of the more important pests that may be carried on nursery stock, with the number of nurseries infested by each for the past 10 years, are shown in the following table: Table 1. Ten-Year Record of Certain Nursery Pests Pest 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 Oyster-shell scale 86 73 68 78 104 93 87 84 53 49 San Jose scale 8 11 10 13 19 17 11 8 2 1 Spruce gall aphids 1 99 124 141 231 244 285 337 306 312 216 White pine weevU 66 74 70 61 67 98 82 101 97 93 Pine leaf scale 10 20 26 46 66 42 72 60 25 50 European pine shoot moth . . 17 32 77 137 120 121 108 128 130 110 Poplar canker 35 23 40 34 39 28 28 26 20 14 Pine blister rust 7 13 12 11 7 2 0 4 5 3 Nurseries uninfested 18 32 24 22 21 16 26 25 32 19 Number of nurseries 302 327 351 362 381 373 380 377 402 399 ' Includes both Adelges abietis and A. rooleyi. Number and Size of Nurseries The list of nurserymen for 1939 contains 399 names, a decrease of three since 1938. A classification of nurseries by size is given in the following table: 228 Connecticut Experiment Station Bulletin 434 Area Number Percentage 50 acres or more 18 5 10 acres to 49 acres 44 11 5 acres to 9 acres 33 8 2 acres to 4 acres 96 24 1 acre or less 208 52 399 100 Of the 399 nurseries listed for 1939, 10 new nurseries were registered and inspected before the spring shipping season and again in late summer. These are marked "(2)" after the name, because each was inspected twice and granted two certificates during the year. Seven nurserymen failed to register before July 1, 1939, and, as provided in Section 2137 of the General Statutes, were charged for the cost of inspection, a minimum fee of $5.00 in each case. All but two have paid, and $25.00 has been turned over to the Treasurer of the Station to be sent to the State Treasury. The area of Connecticut nurseries receiving certificates in 1939 is 4,833 acres, a decrease of 198 acres since 1938. Altogether 30 new nurs- eries have been added, and 33 have discontinued operations either tem- porarily or permanently since last year. Some of these registered, others did not ; but only a few notified this office of their change. Consequently the inspector visited most of them before learning that they were out of the business. A few nurseries listed in 1938 are on the 1939 fist under different names, thus changing the alphabetical arrangement. The nursery firms receiving certificates for 1939 are as follows: Connecticut Nursery Firms Certified in 1939 Certificate Name of firm Address Acreage number Ackerman, H. S. West Hartford 4 4417 Adamcyk, Frank Deep River 1 4724 Adamec Evergreen Nursery, George East Haven 1 4757 Aldrich, Edward Guilford 1 4489 Aldrich, Miss Inie E. Plymouth 1 4637 Allara, Dima Hamden 1 4628 Allen, Henry L. Pawcatuck 1 4737 Amato, Rose Cromwell 2 4725 American Nm'sery & Tree Expert Co. Rockfall 40 4472 Andover Gardens Andover 1 4446 Anstett Nursery, Louis Norfolk 2 4480 Artistree Nursery Branford 3 4490 Austin, Jr., Irving M. Greenwich 2 4823 Backiel, Adolf Southport 1 4632 Bailey's Nursery, Ralph West Cornwall 1 4661 Bakhmeteff, Boris A. Brookfield 10 4654 Baldwin, Linus Middletown 1 4747 Banak Nurseries New Britain 4 4618 Banigan, R. D. Danielson 4 4502 Barnes Bros. Nursery Co., The YalesviUe 200 4686 Barton Nursery Hamden 1 4695 Beach, Roy G. ForestviUe 1 4652 Beattie, W. H. New Haven 1 4714 Bedford Gardens Plainville 1 4549 Bedini, Vincent Ridgefield 3 4741 Beers, Herbert P. Southport 1 4801 Inspection of Nurseries 229 Name of firm Beran Landscape Developers & Florists (2) Berg, Fred Berkshire Gate Nurseries Bertolf Brothers Biehler, Mrs. Augusta Binnenkade's Nursery Blue Hills Nurseries, Inc. Boggini Nursery, L. BoUerer, F. G., Anderson Ave. Nursery Bonnie Brook Gardens Booy, H. W. Boschen, George E. Brack Nursery Brainard Nursery & Seed Co. Branford Nurseries Bretschneider, A. Bridgeport Hydraulic Co. Brimfield Gardens Nursery Bristol Nurseries, Inc. Brooklawn Conservatories Brooklawn Nursery Brooks, H. P. Brookside Nurseries Brouwer Nursery, Jack Brouwer's Nurseries Brouwer's Nurseries, Peter Buell's Greenhouse Burke the Florist Burnett's Corners Farm, The Burnside Avenue Greenhouse & Nursery Burr, Morris L. Burr & Co., C. R. Burwell Seed Co., E. E. Byram Nursery Candlewood Nursery Cannavo, Tony Cardarelli, E. J. Cascio Nursery, The Peter Centerbrook Nurserv & Tree Expert Co. (2) ^ Charlie's Stand Cherry Hill Nursery, Inc. Chiapperini & Sons, Michele Child's Gardens Chippendale Nurseries, Inc. Choate School, The Chudy, Peter City Line Florist Clark, Arthur H. Cleary's Gardens Clinton Nurseries Clyne Nursery «& Florist Coley, H. W. ' Conine Nursery Co., Inc. Conn. Agr. Expt. Station (W. O. Filley, Forester) ris Certified in 1939- -(Continued) Certificate Address Acreage number New London 1 4467 Stamford 4 4418 Danbury 1 4454 Old Greenwich 40 4698 Plainville 1 4552 New London 1 4414 Avon 30 4464 Manchester 1 4588 West Haven 1 4680 Rowayton 2 4807 Yalesville 4 4521 West Haven 1 4797 New Milford 3 4635 Thompsonvilld 14 4655 Branford 6 4766 Danielson 1 4456 Bridgeport 15 4419 Wethersfield 8 4503 Bristol 65 4497 Bridgeport 1 4476 Bridgeport 1 4722 West Haven 1 4562 Darien 5 4670 New London 6 4677 New London 25 4631 New London 4 4479 Guilford 1 4814 Rockville 1 4667 Groton 2 4649 East Hartford 4 4657 Westport 1 4522 Manchester 500 4681 New Haven 1 4794 East Port Chester 1 4738 Danbury 1 4742 AMnsted 1 4457 Cromwell 5 4505 \\'est Hartford 15 4420 Centerbrook 1 4484 East Hartford 1 4511 Rockfall 5 4449 Groton 2 4466 Kent 1 4461 Old Lyme 2 4743 ^^'allingford 4 4693 Danbury 1 4592 Bridgeport 1 4530 Yalesville 1 4816 Bethel 1 4770 Clinton 60 4493 Milldale 1 4668 Westport 1 4643 Stratford 75 4610 New Haven 2 4753 230 Name of firm Connecticut Forestry Nurseries Conn. State Forestry Department Conn. State Highway Department Connecticut Valley Nurseries Cooke, C. W. (2) Corrigan's West Haven Nursery Cronamere Alpine Nurseries, Inc. Cylkowski, B. Daisy Hill Gardens Damen, Peter J. Daniel, Joseph (2) Daybreak Nurseries DeBaise, Pasquale DeMars Nursery DesPierre, Lawrence Dewey, V. E. Dietrich Nursery, Benjamin Dillon, Thomas Dingwall, Joseph N. Dixon, Harry Doane, David F. Donovan, Daniel Donovan, John N. Drenckhahn, Ernest J. Dudley, Grace W. Dunlap's Dollar Evergreens Dunn, John Eager, Edward M. East Haven Nursery Edgewood Nurseries Elfgren Nurseries Elliott, Jessie M. Ellmer, Karl Ellsworth Nursery Elmgren Nursery Elm Grove Cemetery Association Evergreen Nursery Co., The Fairlawn Nursery Fairway Gardens Ferchau, Hugo, Post Road Florist Ferruci, Joseph (2) Flower City Rose Co. FoUett Nursery Fountain Nurseries Foxon Park Nursery Frank & MacArthirr Eraser's Nurseries & Dahlia Gardens Frede, Wm. Frederick Freitag, John G. Galligan, Clarence W. Garden of Romance, The Gardner's Nurseries Geduldig's Florist & Nurseryman Georges HiU Nursery German, Peter B. Giana, John F. Giant Valley Nursery Experiment Station Bulletin 434 IMS Certified in 19.39- —(Continued) Certificate Address Acreage number Deep River 15 4599 Hartford 8 4688 Hartford 18 4581 Manchester 39 4689 Branford 1 4664 West Haven 1 4627 Greens Farms 7 4496 Simsbury 2 4810 Derby 1 4.598 East Haven 2 4509 Bridgeport 1 4576 Westport 3 4758 Walhngford 2 4648 Winsted 1 4768 Hamden 1 4713 Groton 2 4790 Greenwich 4 4746 Greenwich 1 4525 West Haven 1 4482 Stamford 2 4421 Haddam 1 4719 Talcottville 1 4506 Rocky Hill 3 4775 Cos Cob 10 4625 Guilford 1 4796 Cromwell 3 4751 Danbury 1 4817 Bridgeport 1 4563 East Haven 1 4611 New Haven 1 4777 East Killingly 3 4646 Litchfield 1 4802 Cannondale 5 4460 Newington 1 4514 Cromwell 1 4500 Mystic 1 4453 Wilton 30 4422 West Hartford 2 4508 Woodmont i 4558 Milford 1 4748 Bridgeport 1 4765 Manchester 23 4684 Westport 10 4673 Farmington 10 4516 East Haven 1 4560 Ansonia 1 4701 Willimantic 3 4520 Danbury 1 4542 New Haven 1 4703 New Haven ■ 1 4749 Old Saybrook 3 4633 Rocky Hill 300 4595 Norwich 7 4569 Southbury 1 4609 Fairfield 1 4692 Kensington 1 4473 Mount Carmel 1 4733 Inspection of Nurseries 231 Connecticut Nursery Firms Certified in 1939 — (Continued) Name of firm Address Acreage Certificate number Glastonbury Gardens Glastonbury 4 4615 Glenbrook Greenhouses Glenbrook 1 4669 Glen Terrace Nurseries Hamden 70 4601 Glenwood Nurseries Clinton 2 4634 Godfrey, George R., Stratfield Nursery Bridgeport 50 4736 Godfrey Tree Expert Co. & Garden Shop Fairfield 4416 Golden Hill Nurseries Shelton 4756 Goodwin Nurseries Bloomfield 4541 Goshen Nurseries Goshen 4718 Gosnell, Evelyn Westport 4795 Great Pond Nursery Simsbury 4423 Green Acre Farms, Inc. Waterford 4734 GriUo, N. Milldale 4785 Gunn, Mrs. Charles Kent 4803 Haas, Florist Milford 4486 Hall, Henry A. L. West Haven 4596 Hamden Nursery Hamden 4507 Hansen's Florist & Nursery Fairfield 5 4564 Hansen's Garden Newington 3 4617 Happy Days Farm Norwalk 10 4510 Hearn, Thomas H. Washington 3 4597 Heath & Co. Manchester 15 4682 Henninger, Christ. New Britain 1 4726 Hettinger, Joseph 0. Manchester 1 4707 Hildebrand's Nursery Norwich 1 4580 Hilding Bros. Amston 1 4715 Hillcrest Gardens Woodbridge 4 4638 Hilliard, H. J. Sound View 1 4424 Hilltop Nurseries Orange 1 4425 Hinckley Hill Nurseries Stonington 1 4459 Hiti Nurseries Pomfret Centre 11 4612 . Hoffmann's Nursery Hartford 2 4499 Hofmann, WiUiam T. Cromwell 2 4533 Holcomb's Evergreen Nursery Winsted 6 4656 Holdridge & Sons, S. E. Norwich 3 4653 Hope St. Nursery Springdale 1 4793 Horan, J. F. Hartford 1 4662 Horan, Kieran W. West Hartford 1 4784 Horowitz, Ben East Hampton 1 4621 Hosking, James S. Watertown 1 4426 Hotchkiss, H. L. North Haven 1 4526 Hotchkiss, Sr., Wallace M. Norfolk 1 4427 Houston's Nurseries Mansfield Depot 5 4608 Hoyt, Charles E. Bethel 40 4535 Hoyt's Sons Co., Inc., Steplien New Canaan 500 4513 Hurlburt Nursery Hamden 1 4729 Hutt, Robert F. Glastonbury 3 4568 Hyatt, Thaddeus Stamford 10 4798 lies, Jr., Harry (2) Ridgefield 1 4781 Isselee's Sons, Inc., Charles Darien 5 4428 Jennings, Sereno G. Southport 2 4571 Johnson, Lincoln Stamford 15 4546 Johnson, Tom Stratford 1 4788 Joyosa Gardens Cornwall Bridge 1 4728 232 Name of firm Kateley, Milton M. Kauser, Alice Kelley «& Son, James J. Kellner, Arthur H. Kennedy, Wellington Keser's Sons, Inc., Otto Key Rock Gardens Knobling, Edmund Lanedale Farm Nurseries Langstroth Nurseries La Pari, V. Laviola, Cosmo Lawrence Greenhouses Leghorn's Evergreen Nursery Lemmon, Robert S. Lewis & Valentine Landscape Corporation Lewis Gardening Service Linley & Case (2) Lovely Garden (2) Lowescroft Gardens Luce, Mrs. Charles L. Luckey, Ada Mae Luckner, Jr., William Lynch, Mrs. John H. Maplewood Nursery Co. Marigold Farm Marlboro Gardens Mather Homestead Mayapple Nursery McCarthy, John P. McConville's Greenhouses & Nurseries McDermott, E. F. Meier, A. R. Melville Nurseries Merwin Lane Nursery Meyer Nursery, Ludwig Middeleer Milford Nursery Millane Nurseries & Tree Experts, Inc. Mill River Nursery Millstone Garden Minge, G. H. Moore HUl Nurseries Moraio Brothers Morgan, Everett E. Morgan & Sons, Wm. F. Morrison, George Mountain Grove Cemetery Assn., The Mount Airy Gardens Mount Carmel Nursery Munro, Edward A. New England Water Lily Gardens New Era Seed Company New Haven Park Commission New Haven Park Dept., Bureau of Trees Experiment Station Bulletin 434 MS Cebtified in 1939- -(Continued) Certificate Address Acreage number East River 1 4448 Norwalk 1 4791 New Canaan 6 4495 Norwalk 1 4771 Greenwich 20 4813 Portland 1 4732 Newtown 2 4659 Danbury 3 4678 New Csmaan 10 4470 Danbury 6 4469 Trumbull 2 4815 New Haven 1 4616 Branford 1 4780 Cromwell 40 4630 New Canaan 1 4429 Darien 9 4604 Kensington 1 4606 Ridgefield 1 4764 Unionville 1 4570 Manchester 1 4498 Newington 1 4720 Greens Farms 1 4557 Stepney 1 4626 Ridgefield 3 4709 Norwich 2 4786 New Canaan 20 4666 East Hampton 2 4705 Darien 1 4462 Stamford 1 4672 Danbury 2 4575 Manchester 2 4487 Windsor 1 4760 West Hartford 1 4430 Bridgeport 1 4518 East Norwalk 3 4524 Bridgeport 5 4512 Darien 10 4593 Milford 2 4658 Cromwell 100 4431 Fairfield 8 4478 Terryville 4623 Rocky Hill 4534 Waterford 4578 Old Greenwich 4745 Pawcatuck 4809 North Stonington 4702 Yalesville 4819 Bridgeport 4548 Stamford 4577 Mount Carmel 4783 New Haven 4474 Manchester 4566 Clinton 4492 New Haven 10 4614 New Haven 7 4432 Inspection of Nurseries 233 Name of firm Newington Gardens & Nurseries New London Cemetery Association New London County Nurseries Newton's Nursery Newtown Gardens New York, New Haven & Hartford Railroad Niantic Bouquet Shop North-Eastern Forestry Co., The North Greenwich Nursery North Street Gardens Northville Gardens Norwalk Perennial Garden Nyveldt's Nursery Oakland Nurseries Oldfield Nursery Old Orchard Nursery Outpost Nurseries, Inc. Ouwerkerk, Dirk K. Over-the-Garden-Wall Oxoboxo Nursery Palmieri Nursery & Florist Park Place Nurseries Parker, Mrs. Elizabeth Partrick Nursery Pendleton's Flower Gardens Peschko, Robert Pestretto, Frank Pestretto, Salvatore Peterson's Flower Shop Pflomm, Charles ^^'. Pierson, Inc., A. N. Pinchbeck Bros., Inc. Pine Hirst Gardens Pine Plains Greenhouses Piatt, Kenneth M. & Norman E. Polen, Romuald Polish Orphanage Farm Pomeroy Nurseries Prospect Nurseries, Inc. Q Gardens Farm Rahinak Flower Farm Race Brook Gardens Reliable Nursery, The Rengerman's Garden Reveley Landscaping Service, Tlie Reynolds' Farms Richmond, Gordon L. Ridgewood Nurseries Riese, F. K. Riverside Farm Robinson Estate, Seymour N. Rockacres Nursery Rockfall Nurserv Co., The Rolf, Mrs. Fred'H. Rose Hill Nursery Russell Street Perennial Garden IMS Certified in 1939- —(Continued) Certificate Address Acreage number Newington Junction 1 4463 New London 1 4545 New London 5 4679 West Granby 1 4451 Newtown 1 4763 Stamford 4 4651 Niantic 1 4769 Cheshire 96 4433 Greenwich 1 4584 Milford 1 4694 New Milford 1 4731 Norwalk 4 4613 New London 2 4554 Manchester 20 4683 Stratford 1 4755 Norwalk 2 4485 Ridgefield 700 4434 YalesviUe 10 4435 West Hartford 3 4636 Montville 2 4711 New Haven 1 4536 Marion 2 4723 Bridgeport 3 4821 Sandy Hook 1 4740 Norwich 2 4488 Danbury 1 4586 West Hartford 1 4773 Hartford 1 4792 West Hartford 1 4663 Bridgeport 1 4603 Cromwell 300 4481 Ridgefield 10 4640 Guilford 1 4494 Norwich 2 4629 Milford 1 4455 Southport 2 4550 New Britain 1 4594 New Milford 1 4555 Cromwell 30 4531 Milford 1 4779 Deep River 3 4587 Orange 1 4436 East Hartford 2 4642 Granby 1 4706 Clinton 2 4547 South Norwalk 1 4716 New Milford 15 4515 Milford 1 4754 Watertown 1 4676 Milford 1 4582 West Hartford 2 4691 Stamford 2 4824 Rockfall 4 4447 Guilford 1 4475 Gildersleeve 3 4708 Manchester 1 4645 234 Name of firm Sage Brothers Sakson's Nursery Sandelli Greenhouses Sasco Hill Nursery Savanella Brothers Nursery Scarano Nursery, AJphonse Schaeffer, Peter Schleichert Nursery Schneider, Adolf Schuller, John Schulze, Edward E. Scott's Nurseries Scotty's Landscape Service Sears, Roebuck & Company Seltsam's Pequonnock Gardens Seymour Gardens, Prudence Sharon Valley Nursery Silver City Nursery Silver Lane Nursery Simonsen, H. C. Sipocz Arrowhead Farm Soltes Nursery, M. J. Southbury Nursery, The Southington Nursery Southport Nursery South Wilton Nurseries Spring Nurseries Stack, Garrett M. Stafford Conservatories Standish, Norman S. Stannard, Julia State Street Nursery Steck, Charles A. Steck Nursery Steele's Nm-series, Charles Stocking, Milton C. Stray er, Paul Sunny Valley Nursery Sunridge Nurseries Sun Rise Nursery Swendson, Hans Sylvan Greenhouse & Nursery Taylor, Walter G. Tennett, Norman E. Thomson Co., The W. W. Tobin, Daniel J. Tollgate Nursery Torizzo, P. A. Tow Path Gardens, Inc. Tracy, B. Hammond Triangle Nursery Twin Pines Gardens University of Connecticut (S. P. HoUister) Valentine, William Valley View Nursery van der Bom, Mrs. F. \ Experiment Station Bulletin 434 [RMS Certified in 1939- —(Continued) Certificate Address Acreage number Woodbury 1 4556 Greenwich 1 4622 New Britain 1 4710 Southport 1 4674 Torrington 2 4437 Groton 1 4690 Ledyard 1 4787 Bridgeport 4 4517 Milford 1 4583 Higganum 2 4528 Bethel 1 4744 Bloomfield 10 4675 Woodbury 1 4644 Manchester 10 4685 Bridgeport 1 4620 New Milford 1 4468 Sharon 1 4639 Meriden 5 4762 East Hartford 1 4818 Plainville 3 4699 Fairfield 1 4477 Shelton 2 4445 Southbury 4 4523 Southington 15 4532 Southport 35 4491 Wilton 9 4696 Forestville 1 4438 Guilford 1 4782 Stafford Springs 1 4721 Hanover 1 4529 Wilton 2 4799 Hamden 4 4752 Newtown 20 4539 Bethel 4 4647 Greenwich 2 4750 Simsbury 1 4565 Stratford 1 4415 New Milford 15 4551 Greenwich 55 4730 North Haven 1 4624 Cheshire 1 4605 Bridgeport 2 4800 Wallingford 1 4687 Danielson 2 4812 West Hartford 3 4439 Ridgefield 2 4573 Avon 1 4537 West Hartford 5 4660 Hartford 5 4641 Yalesville 1 4590 YalesviUe 2 4440 New Milford 1 4501 StOITS Pomfret Center Southington Bethel 4444 4553 4504 4665 Inspection of Nurseries 235 Connecticut Nursery Firms Certified in 1939 — (Concluded) Certificate Name of firm Address Acreage number Vanderbrook & Son, C. L. Manchester 50 4441 Van Horn & Harrington Suffield 1 4700 Van Wilgen, William Branford 1 4778 Van Wilgen Nurseries Branford 22 4607 Vasileff Nurseries Greenwich 5 4671 Verkade's Nurseries New London 60 458.5 Vernick's Nurseries & Landscape Service Bridgeport 2 4774 Wagner, William H. Woodbury 1 4820 Wallace Nursery Wallingford 4 4650 Wallingford Nurseries of Barnes Nursery & Orchard Co. Wallingford 60 4543 Ward & Son, J. F. W^indsor 1 4452 Watertown Nurseries Watertown 1 4739 Wayside Garden (2) Canton 1 4825 Wayside Nursery Naugatuck 2 4717 Weinberger, William Ridgefield 1 4574 West Cornwall Nurseries West Cornwall 1 4567 Westerly Nurseries Pawcatuck 3 4465 West Mystic Gardens W'est Mystic 1 4519 Westover Trading Corp. Stamford 1 4759 Westville Nurseries New Haven 2 4761 Wethersfield Nursery Wethersfield 3 4712 Wheeler, Charles B. Stonington 1 4591 Whipple, Earle G. Danielson 1 4544 White Memorial Foundation Bantam 12 4776 Whittemore Co., J. H. Naugatuck 3 4442 Wildflower Nursery, The Brookfield 1 4772 Wild's Nursery, Henry Norwalk 30 4471 Willow Gardens Darien 1 4697 Willson, Stewart H Thompson^ ille 1 4561 Wilridge Nurseries Ridgefield 5 4589 Wilson, M. L. Litchfield 5 4704 Wilson Nurseries, C. E. Manchester 1 4806 Wilson Landscape Co., The Hartford 1 4811 Woodbourne Cultural Nurseries, Inc. (2) Manchester 100 4579 Woodbridge Nurseries New Haven 12 4540 Woodcrythe Nursery (W'. S. Sloan) New Canaan 1 4572 Wyllie, David North Haven 1 4559 Yale University School of Forestry Nursery New Haven 1 4443 Yale University Landscape Department New Haven 5 4527 Young's Nurseries Wilton 3 4767 Zack Co., H. J. Deep River 10 4600 Total 399 nurseries 4,833 acres The cost of inspecting these nurseries in 1939, including certain additional visits to make sure that the pests had been eradicated, was approximately $1,735.76, exclusive of traveling expenses. Other Kinds of Certificates Issued During 1939, 135 duplicate certificates were issued to Connecticut nurserymen, to be filed in other states. Altogether 97 dealers' permits 236 ConnecUcul Experiment Station Bulletin 434 were issued to registered dealers who do not grow the nursery stock that they sell. Shippers' permits to the number of 173 were issued to nursery- men in other states, who wish to ship stock into Connecticut. Also, 1,696 parcels of nursery stock were inspected and certified for shipment to accommodate individuals. There were also issued 190 miscellaneous certificates and special permits, 195 blister rust control area permits, 1,204 corn borer certificates, and 2,535 certificates for packages of shelled corn and other seeds, many of which were consigned to foreign countries. Inspection of Imported Nursery Stock Foreign nursery stock enters the United States at designated ports of entry under permits issued by the Federal Bureau of Entomology and Plant Quarantine and is released for transit to destination points, where it is examined by state inspectors. Importation permits are granted for rose stocks only. These ai'e used almost entirely by florists for grafting purposes. Although the number of shipments of nursery stock entering Connecticut from foreign countries in 1938-1939 was the same as the preceding year, the number of cases and plants was smaller, possibly because of increased domestic production on the West Coast. Thirteen shipments containing 37 cases and 276,400 rose plants, all of which were for propagation purposes, were imported. Of these plants 265,600 were Rosa manetti and 10,800 were Rosa miiltiflora. These plants were all imported by four commercial rose growers who received 124,100, 91,500, 50,000 and 10,800 respectively. They came from the following sources: Country Holland England No. shipments 12 No. plants 236,400 40,000 The time required to inspect this rose stock was equivalent to eight days' work for one man and this, together with the travel (815 miles) and other necessary expenses, amounted to a cost of approximately $125.75. Reports of the results of inspection of the 13 shipments were sent to the Federal Bureau of Entomology and Plant Quarantine. Results of Inspection Of the 13 shipments inspected, two, or 15 percent, were found infested with larvae of a sawfly, Emphyius cinctus Linn., which enter the pith of the cut stems of the rose plants seeking a place to pupate. Three shipments, or 23 percent, were infected with crown gall, a bacterial disease. In addition to the rose stocks mentioned above, the following miscella- neous plants and seeds entered Connecticut after federal inspection at ports of entry. These were not inspected in Connecticut: 3,550 pounds of seeds 1,167 rose bushes 234 dahlia plants 20 tubes of orchid seedUngs 4,547 orchid plants 12 Ficus cuttings 5 Primus trees 18,753 gladiolus bulbs 1,495 perennial plants 4 palms 167 miscellaneous bulbs and rhizomes 3 cactus plants 350 azalea plants Inspection of Apiaries 237 INSPECTION OF APIARIES, 1939 R. B. Friend ¥N 1939, Mr. H. W. Coley of Westport inspected bees iu Fairfield, New ^ Haven, Middlesex and New London counties, and Mr. W. H. Kelsey of Bristol inspected in the counties of Litchfield, Hartford, Tolland and Windham. Only two colonies were found infected with sacbrood, and the percentage of American foul brood was slightly smaller than in 1938. Mr. Kelsey reported a heavy winter loss of bees in the four northern counties. Altogether, 1,627 apiaries containing 8,936 colonies were inspected. These averaged 5.5 colonies per apiary as against 6.7 in 1938. There were 147 colonies in 83 apiaries infected with American foul brood ; 20 of these apiaries were inspected twice. The total cost of inspection in 1939 was $1,826.60. Table 2. Thirty Year Record of Apiary Inspection in Connecticut Average Average Number Number No. colonies cost of inspection Year apiaries colouies per apiary per apiary per colony 1910 208 1,595 7.6 S2.40 .28 1911 162 1,571 9.7 1.99 .21 1912 153 1,431 9.3 1.96 .21 1913 189 1,500 7.9 1.63 .21 1914 463 3,882 8.38 1.62 .19 1915 494 4,241 8.. 58 1.51 .175 1916 467 3,898 8.34 1.61 .19 1917 473 4,506 9.52 1..58 .166 1918 395 3,047 7.8 1.97 .25 1919 723 6,070 11.2 2.45 .29 1920 762 4,797 6.5 2..565 .41 1921 751 6,972 9.2 2.638 .24 1922 797 8,007 10.04 2.60 .257 1923 725 6,802 9.38 2.55 .27 1924 953 8,929 9.4 2.42 .25 1925 766 8,257 10.7 2.45 .22 1926 814 7,923 9.7 2.35 .24 1927 803 8,133 10.1 2.37 .234 1928 852 8,023 9.41 2.12 .225 1929 990 9,559 9.55 2.19 .227 1930 1,059 10,335 9.76 2.01 .206 1931 1,232 10,678 8.66 1.83 .212 1932 1,397 11,459 8.2 1.60 J 95 1933 1,342 10,927 8.1 1.69 .208 1934 1,429 7,128 4.98 1.40 .28 1935 1,333 8,855 6.64 1.556 .234 1936 1,438 9,278 6.45 1.429 .221 1937 1,437 10,253 7.1 1.28 !l8 1938 1,609 10,705 6.7 1.18 .177 1939 1,627 8,936 5.5 1.12 .204 Table 2 shows the number of apiaries and colonies Inspected, the average number of colonies per apiary and the average cost of inspecting each apiary and colony for each year since inspection began in 1910. 238 Connecticut Experiment Station Bulletin 434 In 1939 apiaries were inspected in 156 towns. Inspections were made in the following nine towns not visited in 1938: Fairfield County: Easton, Redding, Shelton; New Haven County: Ansonia, Guilford; Hartford County: Enfield; Tolland County: Union, Willington; Windham County: Sterling. In 1939 American foul brood was discovered in the following 48 towns : Fairfield County: Bethel, Danbury, Fairfield, Greenwich, New Canaan, Newtown, Shelton, Stamford, Trumbull; New Haven County: Branford, Meriden, Middlebury, Milford, New Haven, North Branford, Waterbury, Woodbridge; Middlesex County: Westbrook; New London County: East Lyme; Litchfield County: Bethlehem, Harwinton, Litch- field, New Milford, Plymouth, Safisbury, Sharon, Warren, Washington, Winchester, Woodbury ; Hartford County: Avon, Berlin, Bristol, Burling- ton, Canton, East Hartford, East Windsor, Granby, Hartford, New Britain, Plainville, Southington, West Hartford, Windsor; Tolland County: Coven- try, Mansfield, Vernon; Windham County: Windham. Statistics of Inspection The statistics of apiary inspection are shown below. Table 3. Inspection of Apiakies, 1939 Number of Apiaries Colonies County towns Inspected Diseased Inspected Diseased (Am.f.b.) (Am.f.b.) Fairfieldi 22 New Haven ^^ 21 Middlesex 15 New London' 19 Litchfieldi 24 Hartfordi 29 ToUandi 13 Windham 13 156 1,627 83 8,936 147 ' Fairfield County, one apiary inspected twice; New Haven County, one apiary inspected twice; New London County, one apiary inspected twice; Litchfield County, 17 apiaries inspected twice; Hartford County, 24 apiaries inspected twice; Tolland County, three apiaries inspected twice. 2 New Haven County, two colonies sacbrood. Summary of Inspection Apiaries Colonies Inspected, 1939 Infected with American foul brood Percentage infected Colonies treated Colonies destroyed Average number of colonies per apiary 5.5 Average cost of inspection 1.12 .204 Total cost of inspection for 1939 $1,826.60 153 15 1,222 19 115 10 815 20 86 1 840 5 121 1 965 1 318 24 1,570 40 547 27 2,529 56 164 4 515 5 123 1 480 1 1,627 8,936 83 147 5.1 1.6 2] 126 Control of the Gypsy Moth, i938-i939 239 Financial Statement January 1, 1939— December 31, 1939 Disbursements January 1 to June 30, 1939: Salaries S474.00 Travel (outlying investigations) 308.25 $782.25 July 1 to December 31, 1939: Salaries $618.00 Travel (outlying investigations) 426.35 1,044.35 Total disbursements for 1939 $1,826.60 Registration of Bees Section 2129 of the General Statutes provides: That each beekeeper shall register his bees on or before October 1 of each year with the town clerk of the town in which the bees are kept; and that each town clerk, on or before December 1, shall report to the State Entomologist whether or not any bees have been registered, and if so, shall send a list of the names and number of colonies belonging to each. In 1939, 1,627 apiaries con- taining 8,936 colonies were inspected. However, only 861 apiaries and 4,881 colonies were registered. After checking the registrations and inspections, and deducting duplications, the following figures were ob- tained, showing that at least this number of apiaries and colonies were kept in Connecticut in 1939: Apiaries Colonies Inspected 1,627 8,936. Registered but not inspected 324 1 ,563 1,951 10,499 REPORT ON CONTROL OF THE GYPSY MOTH, 1938-19391 J. T. AsHWORTH and O. B. Cooke ■pkURiNG the 1938-1939 scouting season, the gypsy moth control work was carried on as it has been in past years. Trees were examined in the open and in woodlands during the fall, winter and early spring for egg-masses, which were creosoted when found. In the spring infestations were sprayed with a mixture of lead arsenate and water, with fish oil added when a sticker was required, and during the summer months infested areas Vv'ere patrolled to detect gypsy moth larvae (caterpillars). Such work, in one form or another, was performed in 75 towns in Connecticut with the cooperation of the Bureau of Entomology and Plant Quarantine of the United States Department of Agriculture and the Civilian Conser- vation Corps. This cooperation is greatly appreciated, and the writers here express their gratitude to Mr. A. F. Burgess, who has general super- vision of gypsy and brown-tail moth control for the Bureau of Entomology and Plant Quarantine; Mr. H. L. Blaisdell, in charge of field work under ' This report covers the field work from July 1, 1938, to June 30, 1939, not the calendar year 1939. 240 Connediciil Experiment Station Bulletin 434 Mr. Burgess; Mr. S. S. Grossman, under whose direction gypsy moth control work was carried on in the various C.C.C. camps in the central part of Connecticut; and to Mr. A. F. Hawes, State Forester, who has general supervision of the C.C.C. camps. New Equipment In June it was necessary to replace 500 feet of spray hose that was worn out. The usual number of small wrenches and other tools that had worn out or broken were also replaced. Control Operations Following is a brief report for the past year of gypsy moth control operations carried on by the different agencies. Work Performed by State Men The regular state gypsy moth crews operated in Windham, New London, Tolland, Hartford and Litchfield counties. Windham County: Scouting work was performed in the towns of Brooklyn, Killingly, Pomfret, and Putnam, gypsy moth infestations being found in all these towns. Infestations in the towns of Brooklyn, Killingly and Putnam were visited during the larval season and caterpillars were found at all points. No spraying was carried on in this county. New London County: Scouting work was performed in the towns of Bozrah, Colchester, East Lyme, Groton, Lebanon, Lyme, Montville, Norwich, Preston, Salem, and Stonington. Infestations were found in all the towns visited with the exception of Bozrah, Lyme, and Salem. During the larval season the towns of Colchester, East Lyme, Groton, Lebanon, Montville, New London, North Stonington, Norwich, Preston, Stonington and Waterford were visited and caterpillars were found at all points visited except in East Lyme, Norwich, and Waterford. Tolland County: State crews performed scouting work in the towns of Andover, Bolton, Columbia, Coventry, and Vernon, all of which were infested. During the larval season, the towns of Andover, Bolton, Coven- try, Somers, Stafford, and Union were patrolled and caterpillars were found at points visited in Somers, Stafford, and Union. No spraying was done in this county. Hartford County: The following towns were scouted in this county: East Granby, Granby, Hartland, Suffield, and Windsor and infestations were found in all. During the larval season, known infestations in the towns of BurHngton and Enfield were visited, caterpillars being taken in each place. It was in Hartford County that, during the 1937-1938 scouting season, a large gypsy moth infestation was discovered covering an area of about 600 acres in the southern part of Granby, the northeast corner of Canton, and the northwest section of Simsbury. During the 1938-1939 scouting season state and C.C.C. crews destroyed 7,236,186 egg-clusters in this infestation. Because of the size and location of the infested area and the enormous number of egg-clusters present, we decided to forego spraying in other sections of the State. By concentrating operations here we made Control of the Gypsy Moth, 1938-1939 241 an attempt to reduce the gypsy moth population and to prevent the disper- sion of young larvae by wind as much as possible. Just prior to the spray- ing season a project was set up and the work placed in charge of Mr, LaBelle of the state force. A survey of the area indicated that at least five power spraying machines, operating two shifts a day, would be required to complete the project in the time available. This called for 75 men each shift to operate the machines efficiently. The situation was taker care of through the loan of three power spraying macliines and the necessary spray hose from the U. S. Bureau of Entomology and Plant Quarantine and the use of C.C.C. details furnished from Camps Robinson and White, located in the vicinity of the infestation. On the recommendation of Mr. Hawes, most of the lead arsenate used on this project was furnished by the C.C.C. Spraying was started May 27, 1939, and continued through July 1, 1939, at which time the advanced stage of the larvae made further spraying impractical. Approximately 1,562 acres of woodland were sprayed, using 22.5 tons of arsenate of lead. Litchfield County: State crews performed control work in six towns in this county, namely: Barkhamsted, Colebrook, Harwinton, New^ Hart- ford, Torrington, and Winchester. Scouting work was performed in the towns of Barkhamsted, Harwinton, New Hartford, Torrington, and Win- chester, and infestations were found in all except Torrington. Dming the larval season the town of Colebrook was patrolled, and caterpillars were found at points visited. State men scouted 374 miles of roadside and 13,595 acres of open and wooded country, destroyed 426,941 egg-clusters and 19,494 larvae and pupae. Work Performed by C.C.C. jVIen During the past year, details of men from the various C.C.C. camps located in the central and eastern sections of the State w^ere engaged in gypsy moth control work in the form of woodland scouting, cleaning and cutting out infested areas, banding and patrolling for caterpillars. The details from the C.C.C. camps in the eastern section of the State were unable to perform the same amount of control work that they had accom- plished in years past, because, immediately after the hmricane on Septem- ber 21, 1938, all the gypsy moth crews were put on emergency fire hazard work. This continued until the end of the year. The details in the camps in the central part of the State continued with gypsy moth work, with a greatly curtailed schedule, throughout the entire year. These various C.C.C. details scouted 5,673 acres of woodland and 21 miles of roadside, cleaned and removed the underbrush from 551 acres of woodland and destroyed approximately 7,824,665 egg-clusters. This includes the work accomplished in the Granby-Canton-Simsbury infestation previously mentioned. Previous to the larval season, they banded 154,299 trees in infested areas and during the larval season patrolled these banded trees, destroying 27,200 larvae and pupae. WPA Work Performed The Federal Bureau of Entomology and Plant Quarantine, with head- quarters at Greenfield, Mass., again carried on a gypsy moth control 242 Connecticut Experiment Station Bulletin 434 project in this State, using funds provided by the Works Progress Adminis- tration. As usual, the work of this agency was confined to the western part of Connecticut in what is known as the "Barrier Zone", a strip of land extending from Long Island Sound to the Canadian Border, with the eastern boundary passing through the western part of Connecticut. This Barrier Zone was established in an endeavor to stop the spread of the gypsy moth to the west. WPA crews worked in 21 towns in Fairfield, Litchfield, and New Haven counties. During the past season these men scouted 805 miles of roadside and 185,082 acres of open and wooded coun- try, and destroyed 9,034 egg-clusters and 6,457 larvae and pupae. They applied 272,248 bands to trees in and around infested areas previous to the larval season and during the spraying season sprayed 29 infestations in 10 towns in Litchfield County, using 106,202 pounds of lead arsenate. Scouting for Brown- Tail Moth There was no brown-tail moth scouting project carried on in Con- necticut during the 1938-1939 season. Financial Statement July 1, 1938— June 30, 1939 RECEIPTS Appropriation year ending June 30, 1939 $44,880.00 DISBURSEMENTS Personal Services: Salaries $39,011.55 Supplies and Materials : Stationery and office supplies 2.62 Insecticides 156.00 Gasoline 1,022.98 Auto oil and grease 45.67 Chemicals -50 Lumber and small hardware 2.99 Other supplies (miscellaneous) 22.28 Communication Service: Telephone 47.81 Postage 15.00 Transportation of Materials : Freight, express and parcel post -67 Heat and Light: Fuel 21.86 Electricity 15.36 Contingent Expenses: Insurance 409.83 Equipment : Tools, machinery and apphances (new) 385.89 Tools, machinery and apphances (repairs) .' 53.25 Automobiles (repairs) 488.85 Buildings and Land: Rent of storehouse and office space ^ ■ ■ ■ 420.00 Total Disbursements $42,123.11 Balance on hand, July 1, 1939 2,756.89^ $44,880.00 1 Reverted to State Treasury. Control of the Gypsy Moth, 1938-1939 243 O O O O O fO I fO OOOOOOOOOOOOOO' I o lOp—^rHOOO'*OO^O^O^lJ^OO CO t- 0\ 00 LT C^l OOOOOO |o OOOOOOOCOOOOCO lO 1-1 •- o o t— o o o o OO^Ot^'vDO^OeO'#Ot^O'#0 •:* t^ CN -r" I— I On ON OS O LO VO OOOOOO oooooooooooooo (Com OOOOOO 61) e o H s 2 I— I l> (N M fO I—I t? fO CO CO VO ON r— I ■^ CO a-c ■a OS S 3.2 i; ta « o Wag oco i—i CO T— i(Ma\ r-- i— ico coco CO O On ^ O f— I I— I t-- I— I tJ" t— VO 1— I LO to OOOOOOOO OOOOOOOO OS OV •* 00 ro t> OOoOOOOO OOOOOOOO ■^■^1— IIOOCOIN'* (M I— I t^ t> ON (M C\l I— I CO t- CO •^"^1— lOOOIM^-^ O i-H o o C^ T— I Tfi 00 ON VO o -* O ■^ CO ON VO 1-H t- lO CO -^ CO o CO vo CO O C^J O lO o 1— I o c] ON o o o o o ■^ O ON O CO 1-H LO C) CO vo (M On I— I ON ^O •<* r— I O (N i-T co'o" O O O O O Tj" o O O O O O I-H o ■^ O CO o O vo CO O Tj< CO O^. 00 t .2 >> c o o o 3 iS c S .5 fl 5 ^i 5 § -5 ^ 0 2c^ « ^ -3 « 1,-013-3 hT^t-GM^cBb 0 OjScBCOCt-iffl -r i K Control of the Gypsy Moth, 1938-1939 245 H SS Sg 03 "U ^a2 -11 o a z8& gS3o MS m Has ~ S in fo h- o o (M OD t- r— I 03 O ^ O fO O O I ro t~- O O I— I O t~- o o\ o o i-l t^vO r-H CO (M o o o o o C: — I O O C: I CJ OOOOOOOOfM \0 1— I rH \C ON CC CO O IM CO ^ ^ li^ O L*^ r^ O O lO o o f-OLt-^S^O^C: O rM O O ^ o — OC-IOOOO-.^ o c; o r-i o o ^^ ! a o o .ts >>_ eq_S2 o i rq y 3 «^ o o s °5 o 246 Conneclicat Experiment Station Bulletin 434 ss O O U * '=^-§ -1 n ui l-l o 6D to a; w^8 Id a a u o a OOrOOl^OOOlOVOOOVOOOOrHOOO -jHOOi^ONroococoe~io-#OLravooOi— loroo COOOVOCOeO'<*r-HO\CO OirO"-T"C^Jr- ifocoeoc-i CO t- VO (M 10 rf \0 \0 I— I O VO t^ l^ l> 00 (M O CO I— I O (N 1— I coocoe O 10 CO \0 t— I !>• O !N CO >0 CO (M ON_ o^-^^t-^^ '^ 1-H i> f- ON_co__co_r-i o_^__eo o\_ t~-^ edr-Tcoco \o 10 o"cded ■n*" i-ncoin oo I— lOioeNr— IO(NO>00'^TiiOOS* I— I c^v t- a\ 1—10 CO CO 1—1 1— I ON ^ t> r— I p— ( r-l OOt-0-*000(Mr-IOONOinONOtOOOO O^ ON LO Tf< O OD ON ON VO ON ON LO O CO 1—1 in CO ^^ rH O 'OUO f-" 10 (M* t-^'eO Or-l>00(MOOO'*\DOrMOi— irHO'^rOOO 1— IC0C0O^t^V0(Me^1C0\0(MI>C0i— (OCOCOOO ■* CO ■^VOIO t^CO OnOt— ICO 1— lO t- t- ON t>i— I eor— I coiMiM eocNi i-Hi— lOO'*ON'^r-Hm>^i— li— lO^Or— lO^OODOlO i-H CO 1— I r— I I— I I— I 0010 LO O I 1/5 10 CO I CO CN CO I (M 0010 o o I o a I MM G O o el C T5 Ih „ CO I? o or= « Oi^K~^i":" r9 ft '■ 2 3 to '3 Control of the Gypsy Moth, 1938-1939 247 "5^ « a GO 3^3 «.2S ■3 Q ^ Bo a 3"° a. W 3 9 rOOOrHOff\ICOO I TJH s^i t— I Tji o CO LO 1— ( I ^ C0C0COl>lrti— (fOUO iO-^t>COVOi— lost- OM>cs)coa\voo=o » t- ini— I I— I S^ lO OOO^Or— tco^o O ^^^ I— I ON CO t~- i> >o f- r— I C) 0\ i- >o 0\ o fO CO IM >0 fO O ON 0000-*0(N0 0000(MOO\0 t~,\OCOt--f0^roO ON ^ |^^ CO ro CO T}< VO O (M vo e^] vo 20 \D '^ CO -^ C^J o\ O f~l s ^ bri d o i3d o |gd ^^:| Q ^Q o a Q dt«^ UO=)(^ 248 Connecticut Experiment Station Bulletin 434 THE JAPANESE BEETLE, 1939 J. Peter Johnson Quarantine Activities CiNCE 1926, when the Japanese beetle was first found in Connecticut at ■^ Stamford, the Department of Entomology of the Connecticut Agricul- tural Experiment Station has cooperated with the United States Depart- ment of Agriculture, Bureau of Entomology and Plant Quarantine, in conducting the Japanese beetle quarantine in this State. This includes seasonal scouting of certain nursery and greenhouse properties and their sources of sand, soil and manure for classification purposes; the inspection and certification of all articles included in the quarantine regulations; and miscellaneous tasks necessary to the quarantine. Mr. H. N. Bartley, in charge of the federal Japanese beetle office, Boston, Massachusetts, supervises all the Japanese beetle quarantine activities in areas coinciding with the gypsy moth quarantine area. In Connecticut this comprises Hartford, Middlesex, New London, Tolland, Windham counties and a few towns in the eastern parts of Litchfield and New Haven counties, while the remaining portions of the State are super- vised from the New Haven office at the Experiment Station. Scouting Scouting has been conducted yearly and the procedure followed during the summer of 1939 to determine whether or not adult beetles were present on classified properties was similar to that of preceding years. Four crews, each consisting of one foreman and two scouts, reported for work on July 10. Three of them received one day of schooling in the methods of scouting in addition to general instructions. The fourth crew, made up of experienced men, was given instructions and immediately assigned to its territory. The crews followed a prepared itinerary and were stationed at Derby, Hartford, Middletown and Storrs, central locations in their respective districts. They scouted 56 nursery, greenhouse, or other similar establishments, and their subdivisions, a total of 110 units, three to five times. The minimum distance examined around each establishment was 500 feet, A total of 663 adult beetles was found on 34 of the 65 nursery and green- house properties scouted. The crews also scouted the premises of 116 dealers in sand, soil and manure and found 448 beetles on 37 of these. A total of 1,111 beetles were found on the property of scouted establishments, resulting in 11 changes in classification and 24 dropping their classified status under the quarantine regulations. Inspection and Certification The district inspectors responsible for inspection and certification of quarantined materials were located as follows : < The Japanese Beetle, 1939 249 Location No. of Inspectors New Haven 2 ^Manchester 1 iMiddletown 1 iWesterly, R 1 1 Total 5 The total number of plants inspected and certified for shipment to other states and foreign countries was 6,334,633. The number and kinds of certificates issued are shown in the following table : Table 5. Certificates Issued* Kind Farm Products Cut Flowers Nursery and Ornamental Stock. Sand Soil Manure Total "A" "B" Total 16 0 16 12 0 12 36,780 6,799 0 4 4 0 13 13 36,808 6,816 43,579 43,624 * For the calendar year 1939. As in past seasons, the district inspectors were able to make the necessary farm products quarantine inspections in addition to their regular duties. These were few in number and consisted of the following packages: apples 1, beans 15, corn 6, cut flowers 12. Control Activities The control activities in Connecticut ai'e confined to a general survey of the beetle conditions over the entire State, investigation of insecticides for controlling the insect and natural control by use of parasites. The parasite work is carried on in cooperation with the Japanese beetle research laboratories of the United States Department of Agriculture. Adult Japanese beetles were found in Berlin, Bolton, Cheshire, Crom- well, East Windsor, Elfington and Newington for the first time. Eighty towns are now known to be infested and there are probably many others that have not come to our attention. Prevailing dry weather in late June and July delayed the emergence of the adult beetles from the soil. The first one was found on June 22, Usually great numbers appear near the end of the first week in July but in 1939 the hard, dry soil held them back a week or more. Then, instead of a general emergence over a short period of two or three weeks, beetles continued to appear until early in August. The adult population was more uniform than usual over the entire season, from the second week m July until the middle of August, although there were exceptions to this in ' The district inspectors in Manchester, Middletown and Westerly, R. I., were under the supervision of the Federal Japanese Beetle Office, Boston, Mass. 250 Connecticut Experiment Station Bulletin 434 localized areas. A general increase in population was noted in all areas of infestation. Natural spread from local centers of infestation was more noticeable and apparently general. Scouts reported more beetles found in suburban and rural sections than in previous years. The last adult beetle in the season of 1939 was found on October 10. Adult beetle feeding occurred on apple, cherry, elm, horsechestnut, linden, mountain ash, Norway maple, pin oak, plum, sassafras, and Schwed- leri maple trees as well as grapevines and many ornamental shrubs, vines and plants. The skeletonized foliage was more apparent in the late season than in midseason. General feeding took place in Branford, Bridgeport, Darien, D anbury. East Haven, Fairfield, Greenwich, Hamden, Hartford, New Canaan, New Haven, New London, Norwalk, Putnam, Ridgefield, Stamford and Stratford. In some towns it was confined to localized areas and in others was very general. Restricted feeding occurred on some of the more favorite host plants in a few of the towns adjoining those already mentioned. The grubs of this insect damaged or destroyed upwards of 2,000 or more acres of turf in parks, golf courses and lawns. This estimate, in the opinion of the writer, is very conservative. Many acres of turf have been protected by the application of lead arsenate during the past season. The checking of recommended sprays and the development of new materials is carried on with the cooperation of Dr. Philip Garman. Among the sprays tested, lead arsenate is the most satisfactory from a general standpoint. It should be used with a good sticking agent such as wheat flour, fish oil or any of the desirable proprietary agents. Derris (containing at least 4 percent rotenone) with rosin residue must be used weekly to give protection to the foUage. Tetramethyl thiuram disulfide and rosin residue gave promise as a repellent. Derris and tetramethyl thiuram disulfide leave very little visual spray residue and may be used where white dis- coloration is undesirable. Two proprietary sprays containing 4 percent rotenone were used and compared favorably with the derris spray men- tioned above. During May, 1939, twenty-five colonies of Tiphia vernalis Roh., a parasite of the larvae of the Japanese beetle, were released in infested areas in Bridgeport, Devon, East Hartford, East Portchester, Fairfield, Fair Haven, Greenwich, Hartford, Meriden, Montowese, New London, Ridgefield, Waterbury, West Haven and Wilson. Since 1937, 75 colonies of parasites have been released in the State, including releases in Branford, Danbury, New Haven, Norwalk, Norwich, Putnam, Stamford and West- port. The causal organism of a bacterial disease, known as the milky disease, of the Japanese beetle larvae was isolated in 1-933 by workers in the United States Department of Agriculture after considerable study and effort. The bacterium appears to be effective when distributed in areas of heavy grub infestation in New Jersey, reducing the number of grubs appreciably after two feeding seasons, but experimental results to date do not warrant general use by the public. A laboratory method has been devised to propagate the bacterium in quantity. Experimental plots have been established in Bridgeport and New Haven to observe its true value in relation to the control of the Japanese beetle in Connecticut. Mosquito Control in Connecticut, 1939 251 MOSQUITO CONTROL WORK IN CONNECTICUT, 1939 R. C. BOTSFORD A s IN PAST years maintenance of state-accepted salt marsh areas for ■^ mosquito control continued from about April 1 to the middle of Sep- tember. The state appropriation for this work for the fiscal year was $12,000,00. The regular average crew of nine men patrolled the areas as rapidly as possible in order to discover any potential breeding places which might have developed during the previous winter. As soon as discovered, the worst of these were corrected, while those in fair condition were passed by until time permitted attending to them. Many small broods of mosquitoes developed in scattered areas, and a limited quantity of light fuel oil was sprayed on the surface of the water to destroy the larvae and pupae. At Grove Beach in Clinton a large brood had developed to the pupal stage in the ditches which had become stagnant due to lack of water circulation. These ditches were oiled immediately to prevent emergence, and the tide gates were opened to create a circulation of water. Although this occurred twice during the season, no mosquito nuisance was evident. Since this experience, all tide gates have been equipped with an adjustment so that they can be kept from closing tightly. Enough water is permitted to pass through to create the necessary circulation to prevent mosquito breeding. Mosquito control work under the Work Projects Administration con- tinued in cooperation with towns where labor and materials were made available. Although the Station sponsored many projects in name, no actual Station funds were available to cover their obligation as sponsor. In all cases the local town became co-sponsor and provided the stipulated requirements. All federal aid mosquito projects on state-maintained areas were carried on in complete cooperation and with the approval of the Station. Projects on salt marsh areas which in the future may be accepted for state maintenance were given attention. All completed projects have so far functioned to the satisfaction of the Station. The following resume of W.P.A. federal aid mosquito control projects is a continuation of last year's report showing work completed and new work in progress. Many of these projects are town sponsored and may be rated as flood control and sanitation projects with mosquito control as secondary: Ansonla: Cleaniag Beaver Brook; completed. Colony Street, draining swamp and walling up ditch. Town sponsored. Branford: Stony Creek Dike; completed. Here an old stone dike needing frequent and expensive repairs was replaced by a modem earthen dike and concrete tide gate emplacement. Station sponsored. East Hartford: Pewter Pot Brook; Station sponsored by request; completed. Panzy's Pond, correcting drainage. Station sponsored by request. ||, Fairfield: Ash Creek Park and Meadowbrook drainage; completed. Pine Creek Bridge. All town sponsored. Groton: Benham Road and Warren Street, draining swamp. Town sponsored. 252 Connecticut Experiment Station Bulletin 434 Guilford: Great Harbor Dike, rebuilding dike damaged by hurricane. Station sponsored. Hamden: Fairview Avenue, draining swamp and laying pipe. Town sponsored. Madison: Madison Yacht Club Marsh, outlet under construction. Town sponsored. Tuxis Pond, improving drainage. Town sponsored. New Britain: Piper Brook and Bass Brook, corrective work. Town sponsored. New Haven: West River, Wilmot Brook and Lawncrest Brook; corrective work. Town sponsored. East Shore Meadows, improving outlet. Town sponsored. North Haven: Blakeslee Road, swamp drainage. Station sponsored, by request. Norwalk: Lockwood Lane, swamp drainage. Town sponsored. Plymouth: Pequabuck River, corrective work. Town sponsored. Southington: Holcomb School Swamp; completed. Town sponsored. Stratford: Great Dike repairs abandoned. Sniffens Meadow, new outlet. Town sponsored. Bruce Brook, new bridge and corrective work. Town sponsored. West Haven: Berkshire Division, swamp drainage. Town sponsored. Westport: Town Dump Swamp, swamp drainage. Town sponsored. Following is a complete list of proposed projects included in a 1939 state-wide application by the Experiment Station. These have been approved by the U. S. Biological Survey and federal funds have been designated to cover the share of cost borne by the W.P.A. Some of these are already in various stages of operation and many incorporate important improvements to state-maintained areas. This list is subject to change. List of Project Sites Included Under the 1939 Project Application Branford Branford River Repair tide gate Sunset Beach Install tide gate BuUard's Meadow Install tide gate Oppel's Creek Install tide gate ^Stony Creek Complete present project ^Stony Creek Center Clean culverts Sybil Creek Rebuild tide gate Clinton Indian River Install tide gate Point Beach Dig outlet through dunes ^East Hartford. . iPitkin Street Install outlet East Haven Caroline Creek .'.... Install tide gate and jetties Meadow Mere Install tide gate Fairfield Casco Brook Install timber jetties : replace stone culvert with pipe. ^Glastonbury .... Hubbard Brook & Sycamore Street . . Install culverts and correct stream bed. Glastonbury Meadows Install outlet Groton Route No. 215 Install tide gate and outlet Groton Long Point Lower cidverts ; correct drainage Mosquito Control in Connecticut, 1939 253 Guilford iQreat Harbor Repair dike ; install jetties Guilford Sluice Tide Gate Install tide gate Leete's Island Quarry Install tide gate Vineyard Point Install tide gate ^Hamden Church Street Drain pond Oregon Avenue Dump Low spot to be filled Pot Hole North of Skiff Street Low area to be filled Whitney Ridge Manor Stream correction Waite Street Stream correction Mill River — North of Skiff Street . . . Drain low area Treadwell Street FUl low area Waite & Mather Street Fill low area Morse Street Ditch low area Winchester Dump and Powder Farm Stream correction South of Skiff Street Drain low area Madison Canoe Harbor Install tide gate ^Country Club Extension Stream correction Hotchkiss Meadow Install tide gate Foot of Harbor Street Install tide gate East of Norma Dee Cottage Install tide gate Overshore Install tide gate ^Scotland Avenue Lower culvert Foot of Waterbury Avenue Install tide gate New Haven .... ^Little River Install tide gate Hemingway Pond Install tide gate Pardee Street Fill low area ^Parker's Pond Drain pond Strong Street Install pipe line New London . . . ^Briggs Brook Stream coriection ^Coleman Street Stream correction ^Dell Avenue & Mahan Street to Sound Stream correction Fort Trumbull & Cotton Gin Correct drainage Ocean Beach Ditch small salt marsh Old ToAvn Mill Drain low area Shaws Cove Ditching Winthrop Cove Project Drain low area ^North Haven . . . Overbrook Road Stream correction Rear of Germains Correct drainage Norwalk Gulf Oil Co Install pipe line Old Lyme ..... ^Appleby's Pond Correct drainage Sound View Install tide gate Scott's Pond Install tide gate Old Saybrook . . . Plum Bank Correct drainage Stonington Lord's Point Install tide gates, outlets, and ditch areas known as 1, 2, 3 and 4. Stratford Common Meadows Install tide gate Lighthouse Meadow Install tide gate Lordship Road Install tide Westbrook Pochaug River Fill low area Lewis Salt Marsh Install culvert ^Lewis Swamp Install tide gate Stannard's Beach Correct drainage ^Westbrook Center Install culvert and ditch low 254 Connecticut Experiment Station Bulletin 434 West Haven Oyster River Install tide gate ^Anawan Avenue Correct drainage Cove River Install tide gate Westport ^Methodist Church Project Drain low area 2Post Road East of Stage Door Inn . . Correct drainage Saugatuck Shores Install outlet ^West Parish & Center Street Lower culvert ^Peat Swamp Correct drainage 1 In operation. 2 Fresh water work. ^ Subject to inspection and approval of the U. S. Bureau of Biological Survey. The following legislation passed the January, 1939, session of the General Assembly and places all state mosquito work under the new Board of Mosquito Control : "Be it enacted by the Senate and House of Representatives in General Assembly con- vened : "The director of the Connecticut Agricultural Experiment Station, the director of the state water commission, the superintendent of the state board of fisheries and game, the commissioner of health emd one person appointed for a term of four years by the governor, shall act as a board of mosquito control and shall administer the provisions of sections 2415 and 2416 of the general statutes. "Sections 2415 and 2416 of the general statutes are amended by striking out the words 'director of the Connecticut Agricultural Experiment Station' wherever they occur and inserting in lieu thereof the words 'board of mosquito control'; by striking out the word 'director' wherever it occurs and inserting in lieu thereof the word 'board' and by striking out the word 'deputies" wherever it occurs and inserting in lieu thereof the word 'agents." RODENT CONTROL! Howard A. Merrill* Mouse Control T\URiNG the past year (1939) extensive mouse control work has been ■*^ conducted with satisfactory results in Connecticut with a rodenticide in which zinc phosphide is incorporated. The work was carried out in orchards, nurseries, watershed plantings and other reforestation projects. More than 400 growers in the State cooperated in applying poison baits to control the mice on approximately 18,000 acres. The meadow mouse {Microtus pennsylvanicus) control method has been developed to a point at which 90 to 100 percent efficiency may be expected. As a further help to growers, semi-annual population counts of meadow mice are being made. One is made in the spring about apple blossom time and the other during the early p^art of September, by trapping all the mice on numerous plots of one acre each. The areas selected are favorable habitats of Microtus and comprise those that appear to have a relatively high population judging from observations of trails, nests, and feeding signs. Similar work is being carried on in each of the northeastern states, and by correlating the data we expect to be able to forecast what the population will be and to what extent control measures will be neces- sary. 1 U. S. Biological Survey and Connecticut Agricultural Experiment Station co-operating. * Ass't District Agent, Bureau of Biol. Surv., U. S. D. I. Rodent Control 255 During the fall of 1938 the meadow mouse population in orchards under observation was very high, about 100 Microtus per acre. That probably represented the peak of the mouse fluctuation. In several news letters sent out to the fruit growers and at all meetings the point was emphasized that extensive damage could be expected if control measures were not undertaken. It happened that many growers did not complete poison operations until early winter because of the added work resulting from the hurricane. In those cases a great deal of damage was done prior to poisoning. Nurserymen and foresters suffered severe losses of conifers and various deciduous trees and shrubs. Mouse damage in these plantings is not usually an annual occurrence. During the peak years of the Microtus population fluctuations, however, damage may be expected. It is during such years that we hope to be able to forewarn the growers that added precautions may be necessary, for at such times more than one poisoning may be required, because of the "drift", or reinfestation, of the mice. The spring population estimation in Connecticut in 1939, made on four well-distributed areas, showed a marked reduction in mouse popula- tions. The counts ranged from 2 to 24 mice per acre in impoisoned orchard cover. This reduction was noted throughout the northeastern states. The reason for it has not been definitely determined; but, it is felt that climatic conditions may have been an important factor. In September, 1939, thirty-six Microtus were caught in a one-acre orchard plot. Examination of several other orchards had previously been made, and this area gave all appearance of having the highest popula- tion. Pine Mouse Control Pine mouse (Pitymys pinetorum) control is still in the research stage. Results have been effective in certain instances, but have varied with the type of soil, vegetative cover, and the time of poisoning operations. Because pine mice feed both on the surface and underground, the problem is complicated. Areas will be treated during the spring and summer to determine whether or not better results can be obtained at these seasons of the year than in the fall. Different methods of bait application are also being tried. Owing to the heavy sod and soil conditions found in many of the orchards, the probe method has not proved entirely satisfactory, and it is felt necessary to try other means. To determine the rate of drift, or reinfestation, of pine mice into an orchard, a study area has been established in the Hoffmeister orchard at Hamden, Conn., and periodic observations are being made there. Woodchuck Control Many fruit growers annually sustain considerable damage to young orchards from woodchucks (Marmota monax). Much of this damage is done in the spring, when the woodchucks claw the trunks of the young trees and remove the bark. The woodchucks also burrow under the trees and thus cause excessive aeration of the roots and often upset the tree. (See Figure 1). Mowing machines are frequently damaged when they strike the woodchuck mounds. 256 Connecticut Experiment Station Bulletin 434 J^^lISi! ""St^- '-.3i>4 X. -"r^^^ Rodent Control 257 Commercial vegetable growers may also suffer serious injury to their crops through the activities of woodchucks. In woodchuck control it has been the policy not to conduct state or county campaigns. It should be remembered that these animals play an important part in the general wildlife scheme, and usually do not conflict with man's interests. Where they are causing damage, however, they should be controlled. During the past two years research has been con- ducted to develop a gas cartridge that can be easily handled, is reasonable in cost, and will give effective control. In the spring of 1939, approximately 2,000 of these gas cartridges or "bombs" were used by 50 growers. The results were excellent, and many requests were received from other growers who had learned of their effectiveness. During the coming year we hope to have a larger supply and make them available to all growers upon request, A Survey of Mammal Damage in Connecticut Nurseries Numerous complaints pertaining to damage by mice, rabbits, and deer have been received from nurserymen throughout the State. A survey was made to determine the extent of this damage and a considerable amount was discovered in the largest nurseries. In many cases the owners or managers were unaware of the injury until many dollars' worth of valuable stock had been destroyed. The survey was made in 21 of the State's nurseries, including about 3,310 acres, or approximately 65 percent of the total nursery area of Connecticut. Extensive damage, mainly by mice and rabbits, was found in 13 of the 21. Most of the rabbit injury was caused by the eastern cottontail (Sylvi- lagus floridanus mallurus) and the New England cottontail (Sylvilagus trans itionalis). However, some damage in the western part of the State was done by the European hare (Lepus europaeus hybridus). The greatest amount of rabbit damage was found in nurseries where fruit trees were grown. In seven, a total of 15,750 young fruit trees, valued at $.75 to $1.25 each, were injured, with a loss of approximately $15,000. (See Figure 1). In the 21 nm-series inspected, rabbit damage was found in 11 and the total loss amounted to approximately $30,000. Plants frequently damaged were: apple (Mains v.), pear (Pyrns v.), euonymus (deciduous and evergreen), magnoUa, Taxus, maples (Norway and sugar), and elms (American and Chinese). Hunting, trapping, and wire guards were used as means of protection but the results were not satisfactory. In many cases the damage occurred within a very short period of time, and no effective control method was available. It was after this injury was observed and the problems of control discussed with the nurserymen that our interest in the use of repellents was aroused. During the coming year a few experimental tests will be made to determine the feasibiKty of their use. It will not only be necessary to find a good repellent, but this must be reasonable in cost, easy to apply, and most important of all, it must not in itself injure the tender bark of the nursery stock. IMouse Injury Meadow mouse {Microtus pennsylvanicus) damage in nurseries is practically as severe as that caused by rabbits. However, unlike the 258 Connecticut Experiment Station Bulletin 434 rabbit situation, it is possible to control these pests by methods now available. Insufficient knowledge of control methods on the part of the nurserymen is the main reason for the difficulty. Clean cultivation is one of the best means of control, but where sod or mulch is used, trail baiting with the Biological Survey Rodenticide gives excellent results. Of the 21 nurseries inspected, mouse damage amounting to approximately $35,000 was found in seven. The principal plants injured were: dogwood (Cornus v.), Canadian hemlock (Tsuga canadensis), Douglas fir (Pseudotsuga taxifolia), Austrian pine (Pinus nigra), mugho pine (Pinus mughus), yew (Taxus v.), Carolina hemlock (Tsuga caroliniana), Colorado blue spruce (Picea pungens glauca), and Alpine fir (Abies lasiocarpa). Deer Injury The white-tail deer (Odocoileus virginianus) is found to prefer fruit trees in the nurseries as well as in the young orchards. Although other varieties were damaged to a slight extent, fruit trees were most severely attacked. Only one nursery out of the 21 inspected sustained any appre- ciable damage from deer. In this one, 5,000 apple trees, 400 plum trees, and 50 Ginkgo trees were injured. This amounted to approximately $4,500. The amount of deer damage in nurseries is relatively minor compared to that done in newly developed orchards. REPORT ON PARASITE WORK FOR 1939 Philip Garman, J. C. Schkead, W. T. Brigham and G. R. Smith Oriental Fruit Moth Parasites ■jr|isTRiBUTiON of parasitcs and careful parasite studies were continued ■"-^ in 1939. In order to increase om' stock and meet demands from peach growers, some parasites were purchased in New Jersey and additional collections were made by Mr. DeCaprio. We received 115 orders and distributed 6,175,000 Trichogramma, 18,944 Macrocentrus ancylivorus, 2,087 Diodes molesiae and 1,241 Bassus diversus. A few native species were reared from general collections and- placed in orchards where they had not been found previously. Recovery collections were made in a large number of orchards and careful studies of parasite and fruit moth populations were begun in four. Because of additional help in the laboratory during the summer, much time was spent in peach orchards and considerable data assembled. Con- densed results of the first year's work are shown in Table 6. The fruit moth populations are based on egg and twig counts collected on an hourly basis. Survival rates are calculated from the population study to which was applied the reduction brought about by egg, larval and pupal para- sitism. In two cases, the "estimated" population was based on com- parative records from other orchards but no actual counts were made there. As in previous years, low fruit infestation at harvest seemed to be corre- lated with the amount of larval parasitism in July, but there were some exceptions noted this year for the first time. Evidently other factors may influence the end results, and it appears probable that population densities Report on Parasite Work, 1939 259 of the fruit moth may afford an answer. Thus, if we have a population density of 100 units and parasitism amounting to 90 percent, 10 units of fruit moths will remain, whereas if the population rating is only 20, a parasitism of 50 percent will produce the same result, namely a survival of 10 units. Table 6. Condensed Results of Studies on the Oriental Fruit Moth, 1939 Orchard Fruit moth population estimates Relative July survival of fruit moth Elberta infestation at harvest, % Bishop 1939 Rogers Bussa Peters Andrews Hanford Piatt Hurlbutt Musante Bishop 1938 49 2.4 6.0 30 2.7 1.0 36 4.5 11.2 18 6.0 8.0 89 11.7 22.5 200 (est) . 23.7 30.3 125 26.0 31.9 100 67.5 25.2 150 83.9 42.4 200 (est) 117 63.4 Recoveries of introduced species were continued and the following were reared from orchard collected twigs. Species Bassus diversus Diodes moleslae Orgilus longiceps Maximum survival Number of orchards years wheie recovered 6 14 1 Bassus diversus continues to survive in various orchards, but Diodes molestae apparently does not live more than a year in this State. Orgilus longiceps was recovered for the first time in New London County. Japanese Beetle Parasites Cooperation with the U. S. Bureau of Entomology was continued and assistance was rendered in locating points for liberation of Tiphia vernalis colonies throughout the infested area. Twenty-five colonies of this species, each consisting of 100 mated females, were placed in the following towns: East Portchester 1 Greenwich 4 Ridgefield 1 Fairfield 2 Bridgeport 4 Devon 1 West Haven 1 Waterbtiry 1 Fair Haven 3 Montowese Meriden 1 1 Hartford 3 East Hartford 1 New London 1 Total 25 260 Connecticut Experiment Station Bulletin 434 Tiphia popilliavora recoveries were made at six different localities through- out the State where they had been released in 1937 and 1938. Since there have been 23 liberations of this species in Connecticut, the recoveries indicate that at least 26 percent of them have become established. Twenty- one of the 23 colonizations were scouted this year. Recoveries of Tiphia vernalis continue to be made in Bridgeport and New Haven and there are indications that parasitism by the species mentioned is building up rapidly. No systematic scouting program for vernalis was carried out in 1939, however. TESTS OF APPLE SPRAYS M. P. Zappe and E. M. Stoddard fyESTS of various sprays for control of apple pests, both insects and -■■ fungous diseases, have been continued as a cooperative project between the departments of Botany and Entomology. The tests were conducted in the Experiment Station orchard at Mount Carmel. The largest number of trees treated were Mcintosh and Baldwin, but several Fall Pippin, Wealthy, Gravenstein, Greening, Northern Spy, King, Sutton and Stark were included. Two types of sprays were used. Those containing sulfurs were applied to scab susceptible varieties and those without sulfur to varieties not particularly susceptible to apple scab. On the scab-resistant varieties the arsenate of lead-lime-fish oil mixture, which has been used several years, again produced a high percentage of good fruit with an excellent finish. No dormant or nicotine sprays have been appHed to this plot for several years. The absence of sulfur in these sprays has allowed the red mite and aphid enemies to increase so that it has been unnecessary to apply any special sprays for these pests. Sooty blotch and fruit speck have been satisfactorily controlled with this mixture. The materials used in these tests and the timing of the applications were selected to give the greatest amount of protection at the least cost. These tests should be of great practical value to fruit growers when there is a surplus of apples and the market price of the fruit is relatively low. Sulfur Plots Three different kinds of sulfur sprays were used on plots of Mcintosh and Fall Pippin, both of which are susceptible to scab. Applications began with the pink spray May 10, followed by the calyx, 7-day, 14-day and mid-July cover spray. The following materials were used: 1. Dry lime-sulfur 6 lbs. . Arsenate of lead 3 ' ' Water 100 gals. Dry flotation sulfur (with and without spreader) Arsenate of lead .5 lbs. 3 " Water 100 gals. Magnetic sulfur (with and without spreader) Preblossom Tibs. Post-blossom 5 " Arsenate of lead 3 " Water 100 gals. All the fruit on all plots was examined for insect and fungous injury at harvest time, and all injuries, however slight, were recorded. The per- centages of perfect and injured fruit are given in the following table. Tests of Apple Sprays 261 O K CO ABJds on — 5{08qQ jnjjns uoiiB^oJjj jopeaJds jnoqiiM jnj|ns noi'^B'jojj jCBJds ou — 5joaq3 japBSJds qiiM J3pB9Jds 'jnoq'liM jnj]ns-9nii| Xjq japB'dJds \\%i\\ jnjins uoilBloJjj japBdJds inoqijAv jnjins uoiiBjou ^ o LO o pH ■M 'M o o Li t- t- in O C^ 1— 1 o\ LC -* ci 1- I-- L-^ o 02 •^ ^"^ fj ^ ~' £5? — r- o &? CO ON Lt CI 1- t^ S r- cc o 'T 1— 1 *^ o \o M ^ ^ ^o if^ ^ 1- o^. CI ■-C o 'O LC m l^ ss o t- '^ 262 Connecticut Experiment Station Bulletin 434 The spreader used in the above plots was an oil emulsion and its inclusion did not result in any better control of insects and diseases. Both flotation and magnetic sulfur gave satisfactory control of apple scab. The dry lime-sulfur plot had a little more scab than either of the other sulfur plots but the difference was not enough to be significant. Curculio injury was too high in all the plots and accounts for the low percentage of perfect fruit. Conditions for curcuUo damage are very good in our experimental orchard, as adult curculios come from a peach orchard near the apple trees. Weather conditions favored curculios this season and they were more abundant and caused more injury than usual in all orchard sections of Connecticut. Arsenate of Lead-Lime-Fish Oil Plots The rest of the orchard, except for the variety Wealthy, was sprayed with the following mixture: Arsenate of lead Hydrated lime Fish on Water 3 lbs. 10 " 1 qt. 100 gals. The same number of applications were made as in the sulfur plots. Fish oil was omitted from the last application, July 12, because of the danger of excessive spray residue on the fruit at harvest. In order to determine the value of copper sulfate in controlling fruit speck and sooty blotch, two pounds of this material were added to the above mixture in the last applica- tion to half the Baldwin and Greening plots. Table 8. Lead Arsenate-Lime-Fish Oil Plots e8J= oo Good 86.14% 3.65% 86.86% 3.35% 83.75% 90.33% 82.64% Curculio 12.22 67.1 9.38 80.88 11.47 5.57 10.85 Codling moth Other chewing insects .006 1.16 13.84 14.88 0 2.35 3.45 13.29 0 1.79 0 1.01 .01 2.72 Scab .31 .78 .93 8.86 .56 1.53 .21 Blotch .33 62.66 .67 76.12 0 1.82 .12 Cedar rust 2.76 4. This mixture produced a high percentage of good fruit according to our method of scoring. We count all insect or disease blemishes as injured Tests of Apple Sprays 263 fruit, even though such injury is very shght and would easily pass a com- mercial grade. Curculio injury was higher than usual. Some of the fruit was scarred but not seriously injured. A mixture of lead arsenate, lime and fish oil has always been a very effective spray on non-scabbing varieties, and this year was no exception. The finish on the harvested fruit from these plots was much better than on the fruit from the lime-sulfur plots. Codling moth damage was hardly noticeable. Although fruit growers in nearby states experience considerable trouble with this pest, Connecticut orchards in general have had no difficulty with the insect in the past. However, we may have an outbreak some time in the future. Lead Arsenate-Lime-Fish Oil With and Without Copper Sulfate The following table indicates the effect of adding two pounds of copper sulfate to the last spray, July 12, in reducing fruit speck and sooty blotch (fish oil was omitted from the mixture on this date). Sooty blotch is usually negligible on fruit from trees sprayed throughout the season with a lead arsenate-Ume-fish oil mixture, and the addition of copper sulfate did not reduce its incidence enough to pay for the cost of the material. Table 9. Copper Sulfate Plots Baldwin — no copper sulfate Baldwin — with copper sulfate Greening — no copper sulfate Greenings with copper sulfate Good 82.75% 90.66% 89.62% 85.24% Curculio 15.05 8.45 6.32 11.21 Codling moth Other chewing insects .01 1.58 0 .6 0 2.32 0 2.37 Scab .41 .2 1.20 .78 Sooty blotch .45 .16 .76 .63 Wealthy Plots The variety Wealthy was sprayed with the following mixture, the application dates being the same as in the other plots : Dry lime-sulfur Lead arsenate iQlue Water 6 lbs. 3 " 4 oz. 100 gals. The results are given in the following table. 1 "Casco" waterproof glue. 264 Connecticut Experiment Station Bulletin 434 Table 10. Wealthy Plots Sprayed Check (no treatment) Good 72.96% 24.92% Curculio 12.80 47.65 Codling moth .07 .56 Other chewing insects .33 3.05 Scab .31 3.19 Cedar rust 16.18 42.73 The treatment gave a significant control of cedar rust on the fruit and very satisfactory control on the foliage. The 16 percent of infected apples was not of great importance from the standpoint of the production of a commercial crop, as over 16 percent of the fruit was removed in thinning and the thinnings included a large part of the rusted fruit. The above data include all fruit, that removed in thinning as well as that harvested, CONTINUED EXPERIMENTS ON CONTROL OF THE APPLE MAGGOT Philip Garman and J. F. Townsend T\URiNG 1939 a series of experiments was begun in an attempt to learn -^ whether or not there are any means of improving rotenone mixtures for use in killing the adult fly. Experiments covering the effect of light, heat and moisture indicated that high temperatures (100 to 105° F.) for three to five days have little effect in reducing the kill (Table 11). Similarly, high humidity had little effect in these tests. Light evidently plays a more important role, and the active principles are destroyed in a few days by strong sunlight. It seems probable that ultraviolet rays are not the only ones involved, although they are evidently the most potent, since material exposed under window glass eliminating short waves below 3100 Angstrom units was destroyed. The period necessary for this destruc- tion, however, is much greater than for strong ultraviolet radiation. In view of the efficient behaviour of oil-pyrophyllite dusts containing rotenone during 1938 and 1939, it was decided to try them in the orchard. The main advantage afforded by this combination seems to lie in stability against breakdown in storage and rapid settling on the trees which allows one to make heavy applications without excessive drift away from the point of application. Six months after preparation the dust killed just as rapidly as when freshly prepared. Stabilization against breakdown in strong ultraviolet light, however, appears to be non-existent. In the course of these tests we also investigated quebracho-fixed nicotine and Genicide dusts, both of which were without effect in killing the fly. For field work Apothecaries Hall Company of Waterbury prepared 400 pounds of .5 percent rotenone dust (derris containing 4 percent, used Control of the Apple Maggot 265 as a soui'ce of rotenone), to which was added 4 percent white lubricating oil. The carrier was aluminum silicate, known as pyrophyllite. This combination, exposed to bright sunhght (Table 12) in midsummer, retained its effectiveness for 3 hours and for 5.5 hours during an overcast period. Under shaded conditions it was also effective for that length of time. Just how long it remains effective under orchard conditions, especially in the shade, is uncertain. Table 11. Laboratory Cage Tests With Rotenone Dusts to Show Effect of Heat and Moisture in Destroying the Rotenone or Other Active Principle Egg punctures Materials used Treatment after dusting Mortality per female .5% rotenone 4% oU 3 days at 105° F. 30% RH. .5% " 4% " 3 days at 105° F. 80% R.H. .5%, " 4% " 3 days at 104-5° F. 70-80% R.H. .6% " no " 5 days at 104-5° F. 70-80%, R.H. .6% " no oili .6% rotenone no oil ■6% " " " .5% " —oil .5% " —oil Check — no treatment ' Sprayed lightly with water after dusting. In the laboratory tests outlined in tables and text, apples were dusted lightly with the insecticide, after which they were ex-posed to light and hung in the cages with the adult flies. Apples unexposed to Hght were hung in the cages directly after treatment. All cages were kept at controlled temperatures and humidity (76° F. and 60 — 70% R. H.). FHes of both sexes were used in each experiment, the number varying from 20 to 40 individuals. In addition to laboratory test work, a careful field experiment was made with the oil-impregnated dust mentioned above. The mixture was applied with a power duster to Gravenstein, Delicious, and several other varieties. Results were taken from Gravenstein only. Observations made at frequent intervals after applications indicated rapid destruction of the flies at first but their reappearance was noted after four or five days. The same trees were treated with a similar dust in 1938 but, as already reported (Conn. Agr. Expt. Sta. Rul. 428, p. 72), control was not entirely satisfactory theu because of heavy rainfall at critical periods. The rotenone dust used this year is believed to be superior to that used in 1938 because of its property of settling rapidly on the trees and the fact that applications could be made without excessive drift out of the orchard. Samples were taken of drops and picked apples and both were held for some time before cutting open in order to allow maggot eggs to hatch. 100%, in 3 days 0 100% in 3 days 0 100 %o in 4 days 0 100% in 7-8 days 0 100% in 6-7 days 0 100%o in 8 days 0 100%o in 4 days 0 100% in 3 days 0 100%, in 5 days 0 26% in 20 days 26 266 Connecticut Experiment Station Bulletin 434 H O W u< h W C5 ?^ is o « OJ r/1 M m & H P m P O O f^ K t4 w rr M o w 2 S o s H a m S o rt J o (» O 5 o 15 O > •^ O cu ^ Q ® '"OS S CO ec CO CO CO CO CO eo CO a\o\ co eo eo ro CO CO CO CO CO CO CO CO CO cO CO CO CO I— It— li—lr— I ,—t,-^r—{i-i<—l I I ' • I I I I I I— It— Ir— IrH e^]C^CSI«N)(N esiiM(M(N (^J(^^c^le^^(M m 10 o I— 1 1— ( (^ O O O I— I O O O rH O 00 O CO t~- t» CO M tC CO CB CO CO CO a) 03 tn CO ;^ ;>= ;^ ?>. ;>> CO CO CO CO CO •^ ^^ "Xi 'ZS "^ CO CO o o t- t— I (M (N I— I CO 03 CO CO 03 CO CO ;^?^^ CO CO CO 000 (M C-J CO 00^00 00 o o t^ esi o 00 CO CO CT\ vo eo iM O) 3 O ^. », a- ' ~ z z ^ z z z z ^ a o aj cB ^ '— -f^ -t^ fl 2 G B CO CO O CO O o V p c « c ^ H is •^'"■te iSoo 2 2 U^Z 10 Lo 10 10 1/3 10 10 in 10 in m c^ .a.a.a •2 CO o o fe5 fe CO CO OS CO CO CO ON On OS O U « aj oj g u w — OJ 03 5 oj :: z .a: : o ■3 a S a U W Control of the Apple Maggot 267 o A H O O P5 O H o u >- O H « O n -5 d a; Q 6 Q c CO 1-5 > o > o > o d 1-5 oooooooocoo CO 05 01 CO CO o o o CO '13 CO 03 to >^ a -o to >^ -d CO t» CB T3 l-H CO CO CO '^ O a q q c c a &5 fe5 fe5 ^ ^ ^ ..-.--_. CO to CO CO ^cSCdcOcScdcCCScS^ "fl 13 T3 "13 T3 T3 NO o O O lO «^] 13 "O CO CO •S .s .S .£ .3 .3 oooooT^ocor-cNioooooNco ooooovoot-inoNOooooeo be oj oj o CO to CO t/) to to x) 'w a, .5 to CO CO CO 3 3 2 3 3 3 O O O O O O ^ cC J2 X C a B r! C C a; OJ 0) ti a> 0) 0) o; tc be tJC be be be C C fl a C C CO ro CO en CO CO fTl ?^ f^ ^ ^-^ 1^ x-cxj:-o-0'T3'a'0'sZZZZ CO CO LO 'T' -^ UO UO t~- oooooooooooooo lOTT'-^T^iOTjiLomiiomior?'*'!? g g cotocococototot/jtotocococotoad aja)a)tt)aj43ajajaja;aja:!a>ajs-i!H oooooooooooooooo caflCflflflccaccccSc ooooooooooooooii, mLOuoLOuouoirtinmuoirtiniiOLOurj 1— ((McO'^iovor^-eooNOi— iiNco-^i-ovo 65 ^ 268 Conneclicut Experiment Station Bulletin 434 While the average for drops in this experiment is fairly high, it does not appear to be higher than for Gravenstein fruit from nearby orchards where trees were sprayed heavily with lead arsenate. Here the drop fruits averaged 28 percent infested and the picked fruit 3 percent, indicating about the same degree of control as obtained with rotenone dust. One to two pounds of dust per tree per application was used, and the trees were dusted each time from both sides. The program for dusted trees is as follows: (1) Dormant oils for aphis April 6 and 11 (2) Pink: Lime sulfur and 3 pounds lead arsenate plus spreader and safener in 100 gallons May 8 (3) Calyx: Same as pink May 23 (4) First cover: Same as pink June 2 (5) First maggot: .5% rotenone-oil-pyiophyllite July 3 (6) 2nd maggot: " " " " July 11 (7) 3rd maggot: " " " " July 21 (8) 4th maggot: " " " " Aug. 2 The apples handled in this experiment were of especially fine quality, beirig smooth, uniform, and of good color. The treatment did not control European red mite and there was a bad infestation on some of the trees included in the experiment. Results of the count at harvest are given in Table 14. The samples of picked fruit were taken at random to a height of about 9 feet from the ground. Drops were carefully sampled at random. The crop was about the same size as last year. Progress of the infestation in the test plots during two years of treat- ment with rotenone dusts is shown in Table 15. Conclusions While it appears too early to make specific recommendations concern- ing the use of rotenone insecticides for control of the apple maggot, it would seem that such materials may have a place late in the season when it is desirable to avoid poisonous residues. They will doubtless be more successful in dry than in wet seasons, and it should be kept in mind that combinations so far prepared lose their potency even in dry weather. They are not known to last more than four or five days on the trees. The extreme rapidity of kilhng action is in favor of rotenone dusts, as shown by cage tests which frequently give 100 percent knockdowns in 24 hours. Field observations indicate the same rapid destruction of flies in the orchard. Flies coming from unsprayed trees outside the orchard still remain a problem, but there is reason to beheve that the chance of elim- inating late-comers with rotenone dusts is very good. stickers for Standard Spray Mixtures 269 Table 14. Apple Maggot Control, 1939 Variety Gravenstein No. apples Number injured Number Percent Tree cut open by maggots questionable' infested PICKED 1 100 1 ■ 4 2 100 2 2 3 100 0 3 4 181 2 1 5 100 3 0 6 100 2 0 7 100 6 0 781 16 DROPS 10 3.3 1 120 10 6 2 200 15 2 3 200 11 6 4 200 15 12 5 200 44 22 6 200 32 26 7 200 58 23 1,320 185 97 21.4 'Tunnels few and obscure, doubtfully produced by apple maggots. T.\ble 15. Apple M.\ggot Control, 1938-1939 Variety Gravenstein Treatment Year Kind of fruit Percent injured by maggots .5% rotenone dust 1938 Drops 4 applications 1938 Picked .5% rotenone-oil- 1939 Drops p^Tophyllite dust 1939 Picked 4 applications 37 16 21 3 CONTINUED STUDY OF STICKERS FOR STANDARD SPRAY MIXTURES Philip Gakman and C. E. Shepard W/'ORK with Stickers for orchard sprays was continued in 1939. A series " of plots was used in the Burton Orchard at Mount Carmel as well as several rows at the Experiment Station farm. Work with "dynamite" sticker was continued and a new material consisting of bentonite and aluminum acetate was used for the first time. Aluminum acetate has the property of waterproofing spray mixtures and seems to serve as a safener as well as a sticker. Trees sprayed with aluminum acetate-lead 270 Connecticut Experiment Station Bulletin 434 arsenate mixture retained practically all their foliage throughout the season. Analysis of fruit at harvest showed considerable residue, especially where July treatments were made, indicating good adhesion. No lime is required in the mixture, aluminum acetate being safe on apple foliage. Further work is planned with this material. A series of oils, including soybean, Perilla, and fish oil, was compared with aluminum sulfate and a commercial spreader and sticker. In these tests, Table 16, the oils compared favorably, with a slight though probably not significant advantage for Perilla oil. Aluminum sulfate, however, equalled the adhesiveness of the oils for lime-lead arsenate combinations and field observations indicated that it gives less foHage burn in hot weather. A Perilla oil-wettable sulfur combination was also tried with success on Delicious and Astrachan varieties but showed some tendency to drop the foliage of Yellow Transparent. No russetting occurred on apples sprayed with this combination. A series of oil-sulfur combinations was tried on beans under glass, and it was found that Perilla oil gave less injury than most others. Table 16. Loss of Aksenic with Different Stickers Dates of Percentage lost Sticker experiment AS2O3 Pb. RainfaU Perilla oil June 8- -Julys 72 62 4.09 inches Fish oil " 78 62 Soybean oil " 79 69 Commercial spreader & sticker " 83 74 Aliiminum sulfate " 75 67 No sticker " 86 75 Perilla oil July 11- -Aug. 11 35 39 2.14 inches Fish oil " " 49 31 Soybean oil " " 40 43 Conmaercial spreader & sticker " " 62 51 Aluminum sulfate " " 39 28 No sticker " " 65 42 Spray formulae for 100 gallons: Lime 10 lbs., lead arsenate 3 Ubs., plus one of the following stickers Soybean oil 1 quart Perilla oil 1 quart Fish oil 1 quart Aluminum sulfate 3 lbs. Commercial spreader & sticker 1 pint In this series other materials were also added in an attempt to reduce injury, but without success. The quick-drying oils, such as hnseed oil and Perilla oil, when combined with sulfur can apparently be used with less danger of foliage burn than non-drying or semi-drying oils. Mineral oils are especially bad in these combinations. In the field tests, analyses by Mr. Shepard indicated that the arsenate weathered from "dynamite"-sprayed trees at a somewhat slower rate than lime-lead arsenate and Perilla oil, and it appeared possible to place Stickers for Standard Spray Mixtures 271 a much heavier load of poison on the foliage and fruit at the time of spraying. Table 17 shows some of the results outUned above. In these tests, moderately large Baldwin trees were sprayed with a power sprayer, using about 450 pounds pressure and multiple nozzle rods. Samples were taken at random by punching out 1 square centimeter discs immediately after the spray apphcation. A similar sample was taken one month later, the discs being taken from the same leaves and alongside the holes punched when the first samples were taken. A comparison of Perilla oil and "dynamite" stickers, as already mentioned, was made on four Baldwin trees at the Experiment Station Farm. The comparative losses at two different periods is as follows. Table 17. Showing Loss of Arsenic Tbioxide and Lead From Trees Sprayed with Lead Arsenate Plus "Dinaaute" Sticker, AND Lead Arsenate, Lime and Perilla Oil Figures are micrograms per 100 sq. cm. discs Sticker May 261 June 10' Loss % Loss Rainfall ' Dynamite' Loss of AsnOg in first experiment Amount per 100 discs 1,649 1,195 454 27.5 1,482 932 550 37.1 .32 in. Lime-Perilla oil 932 980 741 574 191 406 20.4 41.4 "Dynamite" Loss of lead in 3,080 2,080 2,800 1,700 first experiment 1,000 1,100 32.1 39.2 .32 in. Lime-PeriUa oil 1,860 1,760 1,200 800 660 400 35.4 22.7 Sticker June 231 Aug. 31 Loss % Loss Rainfall "Dynamite" 1,840 1,625 1,171 979 669 646 36.3 39.7 3.83 in. Lime-PeriUa oil 1,028 884 550 478 478 406 46.4 45.9 "Dynamite" Loss of lead in 3,720 2,390 3,310 1,955 second experiment 1,330 35.7 1,355 40.9 3.83 in. Lime-PeriUa oil 1,028 884 550 478 478 406 46.5 45.9 ' Dates of Etnalyses. 272 Connecticut Experiment Station Bulletin 434 The figures above indicate fairly consistent losses both of lead and arsenic in the second experiment but lack uniformity in the case of earlier ones. This may be due to inability to obtain an even cover with the earlier treatment. In the second experiment 10 days elapsed between the spray application and first sampling. This probably produced a more even coating than would have been obtained had the sample been taken imme- diately. It will be noted that the amount of both arsenic and lead was much heavier throughout the season on the "dynamite" trees and also the percentage lost between June 23 and August 3 was appreciably less. These facts are reflected in the amount of good fruit at harvest which was nearly 12 percent more on the "dynamite" trees. However, curculio control, Table; 18, was only slightly better than on the lime-oil trees, and the difference cannot be considered significant. The main advantage apparently lies in control of such insects as the red-banded leaf roller and others, which accounted for a large part of the difference between the two. As outlined in the 1938 report, better than 90 percent clean fruit was obtained with two sprays of lime-lead arsenate and two of "dynamite"- lead arsenate. The amount of lead arsenate on the fruit in 1938 was con- sidered high, even with the last application as early as June 13. This year, with only three lead arsenate sprays (pink, lead arsenate-oil ; calyx and first cover, "dynamite"-lead arsenate) and the last application June 10, there appeared to be no residue problem on Baldwins at harvest. The gap between calyx and first cover sprays was probably too great this year for successful curculio control, though similar conditions prevailed in other orchards where a closer schedule was followed. Table 18. Harvest Examination of Fruit Sprayed with " Dynamite" Sticker and Lime-Lead Arsenate-Perilla Oil Total exam. % good % curculio Lead arsenate and " dynamite " Sticker 1,225 75.8 16.3 Lead arsenate, lime, and Perilla oil 758 63.9 17.1 EXPERIMENTS WITH MANGANESE SULFATE AS SAFENER FOR LIME SULFUR-LEAD ARSENATE SPRAY MIXTURES Philip Garman 'C'OLLGwiNG the introduction of "catalytic" safeners for preventing the well known reaction between lime sulfur and arsenate of lead, experi- ments were begmi in 1937 to determine the possibilities of obtaining a cheap and efficient fungicide-insecticide for summer use on apples — ^and one reasonably free of spray burn. It is understood that the fungicide requirements of some varieties or strains are much less than of others. Mere reduction of lime sulfur content of the spray, however, does not always reduce spray burn but may even increase it. The original catalytic safeners contained manganese sulfate, a buffer agent, and some sulfur. Laboratory work with a number of products indicat- ed that one-half pound of soybean flour in 100 gallons was sufficient to Com Borer Insecticide Investigations 273 afford ample buffer action. Among manganese sulfates used were a number of fertilizer grades as well as the anhydrous products. Some of the fertilizer grades were entirely satisfactory, while one grade containing 10 percent ammonium nitrate served fairly well in orchard tests. The problem then considered was exactly how much manganese sulfate was needed. In the original products, the amount of the manganese sulfate recommended per 100 gallons varied from 4 to 6 ounces. This amount apparently so reduces the fungicidal value of lime sulfur that additional sulfur is needed. It was believed that the manganese sulfate could be cut down to a point where the fungicidal value of lime sulfui' would not be impaired and at the same time provide protection from spray bm'n. Experiments in 1938 on orchard trees indicated that homemade mixtures of soybean flour and manganese sulfate were equal to commercial products. Hence, in 1939, reduction of manganese sulfate was begun, using 2 ounces per 100 gallons with 2 gallons of hme sulfur, and 1 ounce per 100 where 1 gallon was used. These tests were satisfactory on Mcintosh during 1939, where the trees were heavily sprayed from both sides. They were also satisfactory for Gravensteins. During 1938, with a more difficult situation from the disease standpoint and larger amounts of manganese sulfate in the mixtures, results were not satisfactory. It is believed that a cheap and suitable spray can be devised containing lime sulfur, manganese sulfate and the usual amount of lead arsenate, but further tests are neces- sary to demonstrate its efficiency in moist weather. Apparently these sprays must be heavily applied both inside and outside the tree. CORN BORER INSECTICIDE INVESTIGATIONS ^ Neely Turner "poR the second successive year insecticidal experiments for control of ■*■ the Emopean corn borer in Connecticut were made to determine the possibility of modifying the standard schedule by eliminating at least one treatment. Marcross corn was planted April 24; corn borer eggs were fomid May 31 and larvae hatched on June 5. The standard schedule was staited June 7, with further applications June 12, 17 and 22. Commercial dual-fixed nicotine dust (3.75 percent nicotine) was used in hand dusters. The plots were four rows wide and 20 feet long, with each treatment applied on six plots repHcated at random. The season was dry and only one rain, on June 14, interfered with the schedule. Results were obtained on July 17 by dissecting 10 stalks taken at random from each plot. One hundred plants from mitreated plots contained 1,033 larvae. The results are summarized in Table 19. Applications three days apart were more effective than at longer intervals. There was little difference between dusts applied at four-, five- and six-day intervals. Treatment at weekly intervals was less effective, however. The modified schedules of two and three treatments were not as effective as the standard. ' Tests conducted in cc-operation with the Federal Bureau of Entomology and Plant Quarantine, Division of Cereal and Forage Insects. 274 Connecticut Experiment Station Bulletin 434 Table 19. Schedule Tests, First Generation Applications Dates (June !) % reduction of borers % No. 1 borer- free ears 1. Three-day intervals 7, 10, 13, 16, 19,22 75.3 52.6 2. Four-day intervals 7, 11, 15, 19, 23 65.7 46.0 3. Five-day intervals (standard) 7, 12, 17, 22 62.4 48.5 4. Six-day intervals 7, 13, 19, 26 62.4 49.6 5. Seven-day intervals 7, 14, 21 61.5 41.1 6. Three treatments, starting later than standard 9, 14, 19 49.2 31.1 7. Three — ^first standard omitted 12, 17, 22 54.7 35.4 8. Two treatments — early 7, 14 45.2 26.8 9. Two treatments — late 12, 19 43.9 27.4 10. No treatment 13.2 Second generation tests were made on Golden Cross Bantam corn planted June 21 and maturing September 6. The plot layout was similar to that used in the first generation. The standard schedule was determined as August 7, 12, 17, 22 and 27. Rainfall was below normal during the month and did not interfere seriously with the schedule. However, the three applications were subjected to 1.05 inches of rain in six showers between the time the schedule was completed and samples were taken. The results are given in Table 20. There were 932 larvae in 100 plants from untreated plots. Table 20. Schedule Tests, Second Generation Applications Dates (August) % reduction of borers % No. 1 borer- free ears 1. Standard 7, 12, 17, 22, 27 58.5 48.5 2. Fom- — 7-day intervals 7, 14, 21, 28 56.7 45.9 3. Four — first standard omitted 12, 17, 22, 27 54.9 42.4 4. Fom- at weekly intervals starting late 12, 19, 26, Sept. 2 47.9 46.7 5. Three at weekly intervals starting early 7, 14, 21 49.5 35.2 6. No treatment 19.3 None of the modified schedules was as effective as the standard. This type of test has now been made on four generations in two seasons. The 58.5 53.8 48.9 40.0 16.7 Corn Borers and Potato Yield 275 only modification that seems promising is the use of treatments at seven- day intervals, thereby eliminating one application from the standard schedule. Two tests were made comparing a dual-fixed nicotine dust in which quebracho tannin replaced gallo-tannin, with the standard dust containing gallo-tannin. In both tests the materials were equally effective. In one test, hand application of dual-fixed nicotine dust was compared with machine appUcation. The power duster was a commercial machine pushed by hand and fitted with four nozzles. Two of these were directed on each row of corn. The results are summarized below, and show that hand dusting was more effective than machine applications. Comparison of Hand and Machine Dusting % reduction % No. 1 borer- Treatment of borers free ears Hand Machine No treatment The 1939 tests were substantially Icls effective than similar treatments made in 1938. Two facts may contribute to the differences: (1) The 1939 season was dry and in general unfavorable for dusting; and (2) the infestation was heavier in 1939. Regardless of the reasons, the decrease in effectiveness was serious, averaging about 20 percent on the basis of No. 1 borer-free ears. Three tests were made in commercial cornfields. Two of these were reasonably successful but the third was not satisfactory because many borers had hatched before dusting was started. EFFECT OF CORN BORERS ON POTATO YIELD R. L. Beard TN AN effort to determine the economic loss incurred by infestation of ■*■ the European corn borer on potatoes, crop yields for infested and non- infested plants were considered. Two rows of early market (Irish Cobbler) potatoes were grown for this experiment. To insure as near uniform cultural conditions as possible, paired seed pieces were used, that is, for each hill in one row, a correspond- ing hill in the other row was planted with seed cut from the same potato. Although the Colorado potato beetle caused injury in both rows, no definite control measures were employed against it. Feeding practically ceased, however, when the first application of Bordeaux mixture was applied. The usual practice of keeping the plants covered with Bordeaux was followed, requiring four treatments. As far as could be observed, fhe presence of Bordeaux had no effect on the corn borer infestation. 276 Connecticut Experiment Station Bulletin 434 To prevent a natural infestation of corn borers in one row of the potatoes, all plants were examined five times at five-day intervals during the oviposition period of the moth. Wherever found, corn borer eggs were removed. Since the natural infestation was not heavy, it was artifi- cially increased on the second row. This was done by placing on each hill a total of four egg-masses in addition to those already present. Although counts were not made of the eggs placed on each plant, the number approx- imated 100. Since these were almost on the point of hatching, a maximum infestation should have been attained. Larval mortality is known to be high, however, and the number reaching maturity in the potato stalks was small. Dissections of the plants were not made until the potatoes were dug and by that time the dried condition of the stems and the migra- tion of the larvae made an accurate count of the population of mature larvae impossible. Nevertheless, the maximum number of larvae and/or pupae observed per hill was nine, the average number being 2.4. The egg-masses on half of the plants were placed at a low level, near the base, whereas the others were placed on the terminal stems of the plants. No difference in infestation was observed which could be attributed to the position of the egg-masses. A certain amount of migration of corn borer larvae occurred from the infested row to the non-infested row, but not enough to invalidate the experiment. The potatoes were dug on August 11, the yield being as follows: Infested row 164 potatoes weighing 55 lbs. 7 oz. Non-infested row 191 potatoes weighing 54 lbs. 11 oz. These figures indicate that the non-infested row produced more potatoes, but they were smaller judging by weight. Both rows gave yields of almost identically the same weight, which should be the basis of com- parison. The size of the plots was much too small to consider the yield in terms of bushels per acre. The same procedure was followed on two rows of late (Green Moun- tain) potatoes, which are susceptible to attack by the second generation of the corn borer. But in spite of the fact that, as before, four egg-masses were placed on each hill in one row, in addition to the natural infestation, so few of the larvae penetrated the plant tissues that the "infested" row contained no more borers than the non-infested row. The conclusion to be drawn from the experiment on the early potatoes is that an infestation of the European corn borer has no signiticant effect on yield. This is in line with observations made at the Station's experi- mental farm at Mount Carmel in 1937 by K. D. Arbuthnot, of the Bu- reau of Entomology and Plant Quarantine, of the U. S. Department of Agri- culture. It is not possible to confirm these experimental results by observa- tions in commercial potato fields because of the absence of borer-free check areas witliin an infested field. It has been observed, howcA^er, that very good yields of potatoes have beenjobtained from fields with infestations which would be considered severe. Experiments on the Potato Flea Beetle 277 BIOLOGY AND CONTROL OF THE POTATO FLEA BEETLE Neely Turner 'T'HE potato flea beetle (Epitrix cucumeris Harris) has been a serious pest •*■ of potatoes in Connecticut for many years. It also damages newly set plants of tomatoes and eggplants, and has been seen in injurious numbers on cucumbers and garden beans. As a rule feeding on these plants and seedlings ceases early in the season. Potatoes, however, suff"er throughout the season from feeding on the foliage, and in addition the larvae occa- sionally infest the tubers. In Connecticut "pimply" tubers occur chiefly on early (Irish Cobbler) crops. In 1933, 60 acres of Irish Cobblers growing on light, sandy soil were seriously damaged by larvae. The biology and control of the potato flea beetle was studied during the period 1931-1937 inclusive. Most of the work on control was done on potatoes, with a few tests on newly set tomato plants. Seasonal Life History Over-wintering adults have appeared usually during the last week in May. At that time they have been found feeding on weeds, but as soon as potatoes sprout and tomatoes are set in the field, they migrate to these crops. Eggs are deposited on the surface of the ground around potato plants from late in May until early in July. The larvae feed on the roots of the host plant and sometimes on the yonng tubers. Pupation occurs from late in June until late in Angust and emergence from July until late August. Lacroix (5) found that the peak of emergence of adults in Windsor was about the middle of July. Life History Studies Eggs obtained in oviposition cages in the insectary hatched in from six to nine days, the majority hatching in se\ endays. The pupal period was also from six to nine days. On potted plants in an open insectary the total period of development from egg to adult was from 38 to 81 days, with 95 percent requiring from 41 to 55 days. All the data obtained in both seasonal and life history studies indicate that there is only one complete generation of the potato flea beetle in Connecticut. Control Fitch (2) in 1867 suggested the use of inert dusts, such as road dust and lime, as repellents for the potato flea beetle. In 1894 Jones (4) dis- covered that Bordeaux mixture was an excellent repellent, and since his work was published this material has been the standard. In recent years various workers have conducted experiments in which arsenicals were added to Bordeaux mixture. In Connecticut there are really four problems involved in controlhng the potato flea beetle: (a) prevention of damage to tobacco, (b) protec- tion of seedling vegetables and newly set vegetable plants, (c) control of both adults and larvae on early potatoes, and (d) protection of late pota- toes from feeding by adults. Lacroix (6) has reported on the results of experiments on tobacco. 278 Connecticut Experiment Station Bulletin 434 Experiments on vegetable plants. Britton (1) found that tobacco plants could be protected from flea beetles by dipping them in a sus- pension of arsenate of lead at the rate of one pound in 10 gallons of water. In 1932 tomato plants were dipped in such a mixture, and a second lot dipped in a suspension of one pound barium fluosilicate in 20 gallons of water. Neither treatment was satisfactory. In 1934 a dust of barium fluosilicate, one pound, and lime, 3 pounds, was applied to tomato plants three times at weekly intervals starting June 6. There was much less injury to dusted foliage than to untreated plants. In 1936 and 1937 dust containing .75 percent rotenone (pure ground cube root mixed with a clay carrier) was used in the same manner. It was moderately effective. Experiments on early potatoes. Experiments conducted by R. B. Friend in 1928 had shown that arsenate of lead at the rate of 1.5 pounds in 50 gallons of water with one pint of fish oil, was effective in preventing damage by potato flea beetles (unpublished data). Accordingly this material was used in comparison with 4-4-50 Bordeaux mixture in both laboratory and field tests. The following season a dust containing barium fluosilicate, one pound, and hydrated lime, 5 pounds, was tested in the laboratory. The laboratory tests were made by spraying or dusting potted potato plants and caging them with a counted number of flea beetle adults. Results were taken in six days. The tests are summarized in Table 21, and show that Bordeaux mixture protected the foliage but did not kill many flea beetles. Table 21. Laboratory Tests- — Potato Flea Beetle Percent No. feeding Year Material beetles dead marks on one leaf 1932 Lead arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. Calcium arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. Barium fluosilicate 1.5 lbs., fish oil 1 pint, water 50 gals. Bordeaux mixture 4-4-50 No treatment 1933 Lead arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. Bordeaux mixture 5-6-50 Barium fluosilicate 1 lb., lime 5 lbs. (dust) Field tests on Irish Cobbler potatoes were made in 1932, 1933 and 1934. All tests were made on latin square blocks of plots, each plot being 5 rows wide and 16 feet long. The following is the record of the experi- ments: 33 183 27 141 74 49 0 50 0 510 15 26 89 Experiments on the Potato Flea Beetle 279 Year Date planted Dates sprayed Dates harvested 1932 May 2 June 2, 10 & 20 Aug. 8 & 9 1933 May 1 May 26, June 5 & 14, July 1 Aug. 3 & 4 1934 May 2 June 5, 11 & 28, July 9 ' Aug. 6 & 7 The materials used are given in Table 22. The barium fluosilicate was a commercial preparation {Duiox) said to contain 80 percent barium fluosilicate. Table 22. Materials Used — Field Tests on E.vrly Potatoes Materials Years applied 1. Lead arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. 1932, 1933, 1934 2. Calcium arsenate 1.5 lbs., fish oil 1 pint*, water 50 gals. 1932, 1933 3. Barium fluosilicate 1.5 lbs., fish oil 1 pint*, water 50 gals. 1932, 1933 4. Bordeaux mixture 4-4-50 1932, 1933, 1934 5. Barium fluosilicate 1 lb., Ume 3 lbs. (dust) 1934 * Fish oil omitted in 1933. Notes on the condition of plants treated with the various materials were made from time to time during the season. As a rule there was not a great deal of difference in the appearance of the plants until leaf hoppers appeared and caused tipburn. When this occurred those sprayed with Bordeaux mixture were in the best condition, with lead arsenate and fish oil a close second. Plants treated with barium fluosiUcate as a spray looked much like the untreated plants, and calcium arsenate produced results intermediate between untreated and Bordeaux-treated plants. Likewise those plants treated with barium fluosilicate and calcium arsenate died at the same time as the untreated plants, those sprayed with lead arsenate a few days later, and finally those treated with Bordeaux mixture. In all three seasons the plants treated with Bordeaux mixture died at least 10 days after those sprayed with lead arsenate and fish oil. The final criterion of results, the yield of potatoes, was obtained by weighing the marketable tubers by rows or plots at digging time. These results are given in Table 23, in which the average yield per 16-foot row is the miit. Table 23. Average Yield PER 16- ■FOOT Row- — Potato Flea Beetle Control lent Year Treatn 1932 1933 1934 Sprays Lead arsenate— fish oil 9.26 17.38 14.75 Bordeaux mixture 8.10 16.97 14.28 Calcium arsenate 7.28 14.52 Bariiun fluosihcate 7.04 13.67 .... Untreated check 7.06 14.79 9.77 Dust Barium fluosilicate 12.44 280 Connecticut Experiment Station Bulletin 434 The dilTerence between both lead arsenate and Bordeaux mixture yields and the untreated check is significant statistically. However, the slight difference in favor of lead arsenate and fish oil over Bordeaux mixture is not significant. Barium fluosilicate dust was used only one season and was not as effective as the two best spray materials. Irish Cobbler potatoes are grown in two different sections of Con- necticut. In the southern part of the State they are planted early on light, sandy soil and are harvested as early as possible. In the northern section they are grown on heavier soil as an early fall crop, with no particular effort to sell on the early market. As a rule the southern growers dust the crop and the others spray. After completion of these tests one grower in Milford used the barium fluosilicate dust compared with copper-lime dust which had been his standard treatment. The barium fluosilicate dust produced such excellent results that he has adopted it for his entire crop of early potatoes. As was noted above, vines sprayed with lead arsenate and fish oil matured much earlier than those sprayed with Bordeaux mixture, and the yields were about equal. As a rule, the price of potatoes declines steadily from July 1 until late potatoes are harvested. Early maturity is an. advantage in this case and therefore lead arsenate and fish oil should be a more satisfactory spray material than standard Bordeaux mixture. Experiments on late potatoes. Green Mountain potatoes planted about May 15 and harvested late in September were used in tests in 1933, 1934 and 1936. The plots were random replicates of various sizes. The materials and results of the 1933 tests are listed in Table 24. It was evident that the materials which were so effective on early potatoes were not satisfactory on the late crop. This was due to the fact that neither of the new materials controlled leafhoppers. Bordeaux mixture did control leaf- hoppers, and was also repellent to flea beetles. In the same year another test, similar in nature, was made at the Windsor Substation. The results are summarized in Table 25. Here the application of both lead arsenate and fish oil and barium fluosilicate dust increased the yield, but neither was as satisfactory as Bordeaux mixture. Since Bordeaux mixture was a repellent, it was believed necessary to supplement it with some insecticide which would actually kill the flea beetles. The work of Gui (3) had shown that calcium arsenate added to Bordeaux mixture increased its effectiveness in preventing damage by the potato flea beetle. Therefore this combination was included in the 1934 tests. Table 24. 1933 Tests on Late Potatoes Material Applied Yield per plot Bordeaux mixture 4-4-50 June 5, 14 July 19, 29 Aug. 7, 15 135.5 lbs. Lead arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. Same 59.0 lbs. Barium fluosilicate 1 lb., hydrated Ume 3 lbs. (dust) June 5, 14 July 22, 31 Aug. 8, 15 77.7 lbs. No treatment 60.5 lbs. Experiments on the Potato Flea Beetle Table 25. 1933 Tests on Potatoes — Windsor 281 Material Applied Yield per 100 feet of row Bordeaux mixture 8-8-50 May 29 June 8, 19, 30 July 8, 18 Aug. 18 175.5 lbs. Bordeaux mixture 4-4-50 Same 165.0 lbs. Lead arsenate 1.5 lbs., fish oil 1 pint, water 50 gals. Same — except Aug. 18 98.0 lbs. Barium fluosiUcate 1 lb., lime 3 lbs. (dust) Same — except Aug. 18 94.0 lbs. No treatment 76.5 lbs. At the same time barium fluosilicate dust was used for two June applica- tions and followed by Bordeaux mixture during July, August and Sep- tember. The results are given in Table 26. Table 26. 1934 Tests on Green Mountain Potatoes Material Applied Total yield of plots Bordeaux mixture 6-6-50 Bordeaux mixture 6-6-50, calcium arsenate 1.5 lbs.— 50 gals. Barium fluosilicate 1 lb., lime 3 lbs. followed by Bordeaux mixture 6-6-50 No treatment 9 times, June 11 to Sept. 14 870 lbs, Same 749 lbs. 7 times, July 2 to Sept. 14 ' 917 lbs. 389 lbs. In this test the addition of calcium arsenate to Bordeaux mixture was of no value. The combination of dusts and sprays produced excellent results, and was therefore repeated in 1935 and 1936. The results are given in Table 27. In both seasons the combination of dusts followed by Bordeaux mixture produced excellent results, but there was some indication that delayed application of spray was just as effective as the combination or spraying throughout the season. This project was temporarily discontinued due to the necessity for intensive research on control of the European corn borer. Following publi- cation of results of control experiments for the potato flea beetle on tobacco (6), several tobacco growers who also produced potatoes adopted a com- bination dusting and spraying program for potatoes. This consisted in the application of a dust containing from .75 percent to 1.0 percent rotenone 282 Connecticut Experiment Station Bulletin 434 to potatoes, at least two days before application of Bordeaux mixture spray. The dust was highly effective in killing flea beetles, and therefore prevented migration of beetles from potatoes to tobacco following applica- tion of Bordeaux mixture. The expense of the operation was justified by the protection of the tobacco crop rather than by any increase in yield of potatoes. Table 27. Tests on Green Mountain Potatoes Yield, bushels Material Applied per acre 1935 Bordeaux mixture 6-6-50 Barium fluosilicate 1 lb., lime 3 lbs., followed by Bordeaux mixture 6-6-50 Bordeaux mixture 6-6-50 No treatment 1936 Bordeaux mixture 6-6-50 Barium fluosilicate 1 lb., lime 3 lbs., followed by Bordeaux mixture 6-6-50 Bordeaux mixture 6-6-50 No treatment The possibilities of combination dust and spray treatments or of two types of sprays have not been exhausted. It seems logical to attempt to kill overwintering adults of the potato flea beetle during June in order to avoid large populations in July and August. Summary The potato flea beetle overwinters in the adult stage, depositing eggs in June and July, Adults emerge from July until September. There is one complete generation a year in Connecticut, Seedling and newly set vegetable plants may be protected from flea beetle damage by a dust containing at least .75 percent rotenone. On early (Irish Cobbler) potatoes a dust containing one pound barium fluosihcate and 3 pounds hydrated hme, or a spray containing 1.5 pounds arsenate of lead and one pint fish oil in 50 gallons of water, were most satisfactory. On late potatoes (Green Mountain) Bordeaux mixture was necessary for control of leafhoppers. Addition of calcium arsenate was apparently of no value. A combination of dusting and spraying was tested with inconclusive results as regards yield. 7 times, June 13 to Aug. 15 217 4 times, July 11 to Aug. 15 212 4 times, July 11 to Aug. 15 223 134 7 times, June 11 to Aug. 8 214 June 11 4 times, July 8 to Aug. 9 213 4 times, July 8 to Aug. 9 191 152 Wireworm Injury to Potatoes 283 Literature Cited (1) Britton, W. E., 1907: "Insect Enemies of the Tobacco Crop in Connecticut." 6th Kept. State Ent. of Conn. (2) Fitch, A., 1867: 11th Kept. Insects of New York. (3) Gui, H. L., 1932: "Control of Potato Flea Beetle on Potatoes." In 50th Annual Kept. Ohio Agr. Expt. Sta. Ohio Agr. Expt. Sta., Bui. 497. (4) Jones, L. R., 1894: "Spraying Potatoes." Vermont Agr. Expt. Sta., Bui. 40. (5) Lacroix, D. S., 1932: "Tobacco Insects in 1931." Conn. Agr. Expt. Sta., Bui. 335. (6j • — 1935: "Insect Pests of Growing Tobacco in Connecticut." Corm. Agr. Expt. Sta., Bui. 379. SURVEY OF WIREWORM INJURY TO POTATOES R. L. Beard ■fN October, 1939, a preliminary survey of wireworm injury was n •^ in 17 fields of potatoes, chiefly in Tolland County. In each field the ex made extent of wireworm feeding was estimated, soil samples were taken, and the history of the field insofar as possible was recorded. A satisfactory estimate of wireworm injury to potatoes is difficult to obtain. An estimate based on reports of growers at time of grading is not reliable because of the personal factor involved. Moreover, since the potatoes are not thoroughly cleaned prior to grading, many with superficial feeding scars are overlooked by even the most conscientious graders and will not be noticed by the buyer. This means that the number of potatoes culled because of wireworms is much smaller than the number actually scarred. In the present survey, the estimate was made by individually brushing and examining several hmidred potatoes in each field. All those showing any evidence of wireworm feeding, however superficial, were noted as being infested. This method, too, has its disadvantages. The samphng is time consuming, and since the potato digging is done in a short time, a relatively small number of potatoes can be examined. Even 500 is a very small sample in a field several acres in extent which may yield in excess of 400 bushels per acre. Also, it is difficult to sample the field in a random manner. As potatoes are harvested, the picking crew follows so closely behind the digger that the area of samphng at any one time is limited. Thus, unless considerable time is spent in each location, the entire field cannot be sampled. In recording the samples, units of 100 potatoes were considered. The fact that within a field the infestation in each unit did not vary greatly from the others indicates that in spite of the small size of the sample, a representative estimate was obtained. The percentage of potatoes showing evidence of wireworm feeding, together with the type of crop grown in each field in previous years, is here tabulated. 284 Connecticut Experiment Station Bulletin 434 Table 28. Location, Previous Crop and Wireworm Infestation Number of field Location %of potatoes infested 1935 Crop grown on la 1936 1937 nd 1938 1939 1 E. Windsor 2.3 Tobacco . 25 years .... Potatoes 2 S. Windsor 4.0 Tobacco . Potatoes 3 Somers 8.7 Potatoes Potatoes Tobacco Potatoes 4 Somers 9.6 Tobacco Potatoes Potatoes Potatoes 5 Ellington 13.3 Corn and grass Potatoes Potatoes Potatoes 6 Somers 14.6 Corn or tobacco Clover sod Potatoes 7 Ellington 18.0 Potatoes Clover Potatoes Potatoes 8 Ellington 21.0 Potatoes Tobacco Potatoes Potatoes Potatoes 9 Ellington 22.2 Potatoes Potatoes Potatoes Potatoes 10 E. Windsor 23.5 Potatoes . 9 years 11 Somers 25.7 Timothy and clover Potatoes 12 Somers 27.0 Potatoes Clover Clover Potatoes Potatoes 13 Somers 31.2 Potatoes Potatoes Potatoes Potatoes Potatoes 14 Somers 32.3 Potatoes Tobacco Tobacco Potatoes 15 S. Windsor 33.2 Potatoes . 8 years 16 Somers 38.0 Weeds Weeds Weeds Weeds Potatoes 17 Ellington 66.6 Corn and grass Potatoes Potatoes Potatoes In line with the belief that continued clean cultivation of the land results in an absence of wireworms, the two fields showing least injury had been planted to tobacco for many years prior to 1939. On the other hand, continued planting of land to potatoes, which are considered a cleanly cultivated crop, does not bear this out, so far as the present evidence shows. Otherwise, no conclusions can be drawn from these data relative to the type of crop rotation unfavorable to the wireworm population. Of course, strict comparisons of the fields are not possible because neither the wireworm populations nor the degrees of infestation are known for previous years. As far as can be judged from the statements of potato growers, wireworm injury in 1939 was less than in preceding seasons. Soil samples were taken from each field and analyzed by the Soils Department of the Experiment Station. No correlation could be observed between the wireworm injury and the physical and chemical nature of the soil. Control of Squash Insects 285 CONTROL OF SQUASH INSECTS R. L. Beard Summer Squash 'X'HE CHIEF insects causing damage to summer squash are the striped ■'■ cucumber beetle (Diabrotica rittata), the squash vine borer (Meliitia satyriniformis), and the common squash bug (Anasa tristis). The cucumber beetle appears in numbers early in June, and young squash plants, if not given protection at this time, may be completely destroyed. Later in the season the beetles, though present, are less abmidant, and the squash plants, because of their larger size and greater vigor, are better able to resist the feeding injury. The larvae feed on the roots of the plants and the beetle is instrumental in transmitting the bacterium Bacillus Iracheiphilus, which is responsible for wilt disease. Many dusts are in common use against the beetle, but most of these have only a repellent action. A derris dust containing .6 percent rotenone is to be recommended over other treatments, for this material serves not only as a repellent, but as both a stomach and a contact poison. The adult moth of the squash vine borer is in flight during the month of July and eggs are deposited on the basal portions of the squash stems. The borers which hatch from these eggs tunnel into the stems and are frequently responsible for the sudden wilting of an entire plant. On Hubbard squash, nicotine sulfate and lead arsenate have both been employed successfully against the insect, but these insecticides are not desirable for summer squash because of poisonous residues on the fruit. The squash bug begins to lay eggs the middle of June and, although it continues into September, about 80 percent of the oviposition is com- pleted by mid-July. The young nymphs feed on the leaves and stems of the plants, causing localized injury. Severe injury is seldom caused by the bug except in conjunction with other insects. Although a very con- centrated pyrethrum (Pyrocide) dust or spray is effective, the spray is too inconvenient to prepare and the dust is too expensive for common use in controlling the bug. Thus, although the chemical control of the cucumber beetle is efficient, that of the squash vine borer and the squash bug is not. It is possible, however, to avoid economic loss due to these last two insects by planting two crops of squash in sequence. The time of the plantings should be such that the first crop, receiving the bulk of the infestation, can be destroyed when the second comes into bearing. During the summer of 1939 this method was demonstrated to be satisfactory. The first planting of squash was made on May 8. This came into bearing the latter part of June, and a prolific yield was maintained throughout July. By the middle of July squash vine borer injury began to appear, and by August production of squash began to taper off. This curtailment was due to no single factor, but to a combination of dry weather, damage caused by the above mentioned insects, powdery mildew, and a leaf spot disease. Two planting dates were tried for the second crop, namely, June 28 and July 5. The latter date proved to be some- what more satisfactory. Squash from this planting was picked within 286 Connecticut Experiment Station Bulletin 434 four days of that from the June 28 planting, and there was less insect damage. Since the heaviest attack of both the squash bug and vine borer occurs before the middle of July and is directed against the larger plants, only the first crop of squash was severely infested. The squash bug con- fined its activities to this crop, and the vine borer caused only a negligible amount of injury to the June 28 planting of the second crop. Not only was the second crop of squash free from insect trouble, but it assured a continued production of squash of good quahty. At the time it came into bearing (the second week in August), the old vines of the first planting were coarse and unhealthy, and the fruit, maturing slowly, had a tough appearance. The new plants, on the other hand, were vigorous, clean in appearance, and bore an abundance of tender fruit. Production was curtailed prematurely in September by a severe attack of powdery mildew. Undoubtedly the optimum planting date for the second crop of squash would vary from year to year with changing weather conditions, but, considering the life histories of the insects in question, July 1 is recom- mended. This is late enough to preclude the possibility of the young plants attracting an appreciable number of insects from the first planting, and yet early enough for the plants to mature and bear fruit unless the weather conditions are extremely unfavorable. As soon as the second crop of squash begins to bear, the old vines of the first planting should be destroyed to reduce the insect population. Hubbard Squash The insect most destructive to Hubbard squash is the squash vine borer. The cucumber beetle attacks young plants in numbers, but can be controlled easily by dusting, as on summer squash. The squash bug is usually not present on Hubbard squash in sufficient numbers to cause damage. It has been shown by Friend (Conn. Agr. Expt. Sta., Bui. 328) that good results in controlling the squash vine borer can be obtained by using nicotine sulfate to kill the eggs or by spraying with lead arsenate and fish oil to kill the young larvae before they enter the stems. The number of inquiries concerning this insect, however, has seemed to justify a further consideration of the problem. Accordingly, in 1939 insecticide experiments were conducted on a small scale. The treatments employed included lead arsenate and fish oil. Western dynamite spray, and dual-fixed nicotine dust. The Western dynamite spray is lead arsenate prepared as an inverted emulsion with oleic acid and triethanolamine. The lead arsenate in both this spray and with the fish oil was used at the rate of 3 pounds per 100 gallons of water. The dual- fixed nicotine is a dust now in use in controlling the European corn borer. All of these insecticides act as stomach poisons, and to be effective must be present on the stem of the plant at the time the larvae bore their way into the tissue. Since eggs of the vine borer are deposited the last of June and through the month of July, four applications were made at weekly Effect of Salt Water Spray on Foliage 287 intervals, beginning on July 3. At the end of the growing season, all of the squash produced was picked and weighed, with the following results in yield: Average no. Average no. No. of hills squash per hill lbs. per hill Check 8 2.1 6.6 Lead arsenate, fish oil 10 3.4 13.6 Western dynamite spray 8 3.3 14.3 Dual-fixed nicotine dust 8 3.8 14.6 Although a satisfactory evaluation of the treatments cannot be made because of the small size of the plots, all of the treatments resulted in a significant increase in yield over the untreated check plot. The favorable showing of the dual-fixed nicotine dust is promising in view of the greater ease of application of a dust as compared with a spray. The experiment should be repeated, utilizing larger plots, before a definite recommenda- tion of this dust is made. FURTHER OBSERVATIONS OF THE EFFECT OF SALT WATER SPRAY ON FOLIAGE M. P. Zappe and E. M. Stoddard 1 nnuE original observations on salt water spray injury were made shortly •*■ after the tropical hurricane which struck New England on September 21, 1938 (Report of the State Entomologist for 1938, p. 103). The informa- tion in the present article is based on observations of the same plants during the summer and fall of 1939. Some of the evergreens had made a fair recovery, while others were dead or so badly injured that it was not worthwhile to attempt to grow them for several years in the hope that they would eventually recover. In most cases the most rapidly growing evergreens or the smaller plants made the best recovery, although the smaller plants of hemlock and Chamaecvparis were almost completely killed in the fall of 1938. In the following table, salt water spray damage was classified into one of the following grades : "none"^ — no visible injui'y was noted. "slight" — damage was noticeable but not serious, and plants stood the injury fairly well. "medium" — the injury was very evident and leaves were half burned. "severe" — the salt spray burned the entire foliage or, in the case of deciduous trees, almost completely defoliated them. In addition to the 1938 fall observations, further notes were made during 1939 on May 16, June 22 and November 8. The following table gives the results of these observations : ' The writers wish to thank Mr. Henry Verkade of New London for assisting in naming some of the horticultural varieties of evergreens and for some of the observations made in his nursery in the town of Waterford, Conn. 288 Connecticut Experiment Station Bulletin 434 O < < < a, CO H C/3 S ■> O bCbDbcS>>bCajQJ>S5S5SS-sSS a;:3;s;s o « 33:3 cEtD222g°°fe£c° £ 5-3 j3j: ^ > 5 be &X) g oj c :^— 2 73 C tn 7j G £ £ £ p OJ 3 3 3 OJ S 5 -3 -3 "3 a; > > OJ OJ Oi > <0 Oi r' a c ^ (/3 oi C C C t/j be 3 .2. £ 2 2 2 2 S-eS'S^ 0:1"^= 2 q-^-S CO c (1) 0^ !D ^ o; q; -c S 2 2 S 53-3^^3 5SS53552222 2-== a3 73 c/: G G v; ao cc c/; y; CO a; ^0)33333"^ ft e 3 a bn C s ■3 crt t- 0) OJ t- rv ft Q a; r '3 !- •- 3"3-!= ft 2 15 OJ 4J 3 r-.tr ft 3 ft ft 3 i. 3 a; ft 2 3 «-3-3.&3 ft ft c '3' £-3,--^U 3SZ3BP3- 3 ;-^ 3' ,3^3 3 ^ ^ T3 '"'Sr^BiDraiftajcWa;^ a; o 3 'ft 'S «.£ !-.£ ft "^ f^ 3 ^ 3 O) O " ■^ « '3 3 «, ~ e g.§ *-C^ siiecica pyramida pfilzerian 2F c II to C 3 . - ^ :; £ ^ S't e S~ u !- -i;-o- a;22-3j3a;s^St S X 3 3 M o-j OJ ^ ^ 03 aiajBBa3ccSsS;Ot»Oai •^ ^ ^j OJ ™ cc -, ;_ JU 0^ e ftO S .£ ^ ft ft fto SE ?^ ^.- 2 « 5iij C x tn xi C C X C :C C '/! » C C/3 tC «3 33 CC a; C 03 C O! « a; a; o; o; « s^ C C C C C C g O O O O O O S c c c c c c S ti£'>bcCti£6X)gbtCiy^t£CS Sij>>cb£C;,ebc s aj;:= 2 = = c— 2;r;z; 2 c — 5 oj p— 2 oj 2:= Oi v-j cc G y; y; S cc C x «;■ C S m J a: C K C c« C ai 0^ o a;) 0) a^ Q^ C C C e C C o o o o o o c c a c c c ^ o S S C £ 53 -^ S 'Ji X' rfi C £ £ > a; « t>C > SE S 73 C C K) aj z; C « S « 5<=-^ Ig-g-s CO :!"' CO "O "O . cc oS+jCO^CBCBS-c 2 3c _ ^ %.% - Q, u; « « c > is ^ S a 4J C CO »^ -S s c CO '"'cc ;. •- C - .= C3 CO ^ H 3 -P c" a; t; G j2 5 a; ^ E o o CO -Q > S o a; J3 C ■<- o; CO CO > a; ^ CO > ^ rocar auca glau( mac ca gl Isa ta gens ■§ CO ~ H) -^ c 3 C !j -s is s •i) .^ c '- ? Ss D 4i ^ ^ ^ - ^ 3".^' ' ' ' : 5 oa. E-H S.e ^-g .■5 e- ir-s e -s' -5 e S "5 O JJ o •2 e c 2 „ S-c r (^ 11 1 s 5^ h: : : : : -Si- - 290 Connecticut Experiment Station Bulletin 434 3 .a 1=1 O u H O OS > m CO a o a; O q; CO b o ^1 C a cs c "o ^- so o * a SI o o t-i a; « "2:: 3- A ^ :^ « « 2 ^ Ifl ^ v^ .s o a o a ^ a 3 ^ 3 ^ ^■-3 0) ?^a a ^ 3 OJ be -^ O ^ O c a. « ^ £ -S >s > CO CO CO g>^ CO^ o IB 4J CO 4) > 03 OJ 41 « 0) > > a; > be > lU S a; c/1 c« CO CO CO CO « "O ^i: g 5 ^^s-S _^ O ai ™ CO fc< > fl !- g OcO^^ CO pa 1-5 • (O CO § 4J H?Pa N 3 3 l.^" Illi fe ^ CO CO CO ^CC ^ ■^ . S «^ «« it-H =— "O ~o u'x.'aajz-o •^ _i.ji _i_:i j_j .i_J ^ ■ • ■ -c c S c CO o o o o _ o o o o S o. a On fi< c ?_, L- S^ Lrf t4 &H tN *"^ tn ^i 5a)a}(i3aja)>>>>>>bp>,bp ■§5 i5<-fi CO « 3 a almaluni \s palustr us indron pumila us sp. (?) schlippe c o -c-d Effect of Salt Water Spray on Foliage 191 a o o m H H a a m rjj -a o c ■o a bD ^ .a o ^ 3 «§. 03 o o be 3 O a be C8 • 2 &> -2 c^ q: ^ 292 Conneclical Experiment Station Bulletin 434 Although most of the evergreens were more or less injured by the salt spray, the pines and spruces showed less injury than many of the other types. White pine, however, was badly damaged; shortly after the hur- ricane all the foliage became brown and eventually dropped off. Many of the buds were not killed and the trees leafed out in the spring, although the foliage was weak and rather yellow. White pines in exposed places near the shore front were dead on the windward side the next summer. Most of the junipers were seriously injured except the Greek, Swedish, creeping and shore junipers which made a very good recovery during the following summer. Although all horticultural varieties of Chamaecyparis were injured, the p is f/em varieties were most seriously affected and many of them, particularly the smaller ones, were actually killed. The obtusa varieties were not so seriously affected and made a good recovery. Hem- locks were badly injured. Many were dead or of no value if alive, but the Japanese hemlock was only slightly injured and made a good growth during the next summer. The yews were only slightly damaged and made a good recovery. Arborvitaes were all damaged, some rather seriously, except Rosenthal's and the giant arborvitae, which withstood the hurricane and salt spray much better than the rest. Most of them will outgrow the injury in about two years. Douglas firs lost practically all their foliage and did not recover very much during the first summer after the storm. It is doubtful if they ever will be of any value. The Cryptomeria came through the storm in good shape and showed no partic- ular injury. The broad-leaved evergreens as a group were rather badly damaged, Japanese holly and daphne showing the least injury. The andromedas were severely injured and most of them were dead or worth- less by the spring following the hurricane. The deciduous plants varied considerably in their ability to withstand the wind and salt spray. Many of the trees were entirely defoliated by the storm. Some of them, especially the maples, started new growth in October, 1938, and went into the winter in a weakened condition. During the following summer the foliage was small, scanty, and of poor color. Many of the smaller branches and twigs died, and, in the case of Norway maples, larger branches were also killed. Frequently the bark on the main trunks of the Norway maples split during the winter, and this injury was followed in the summer by the development of Nectria cankers. In some cases this will result in the death of the trees. In New London County these cankers were very common on the maples and may be the cause of serious injury for some time to come. Horsechestnuts were least injured of the deciduous shade trees and appeared in perfect condition the follow- ing summer, even though they showed a fall growth and some even blossom- ed again after the storm. We know of none that were actually uprooted during the hurricane. Deciduous shrubs lost most of their foliage during the storm, but the following spring leafed out normally in most cases and continued to make a good growth throughout the season. Most of the azaleas (except Schlip- penbacki) and magnolias were severely injured, and many of them were dead the following spring. It is interesting to note that red dogwoods and small hemlocks which were protected during part of the storm by blown down trees and portions The Smaller European Elm Bark Beetle 293 of wrecked buildings were not seriously injured and made a good growth the following summer while those left exposed were dead or nearly so. References to Salt Spray Injury to Trees and Shrubs Boodle, L. A., 1920: "The scorching of foliage by sea winds." Jour. Ministry Agr. Great Britain, Vol. 27: 479. Moss., A. E., 1939: "When it rained salt water." ^\merican Forests, Aug., 1939. Wallace, R. H. and Moss, A. E., 1939: "Salt spray damage from recent New England hurricane." Fifteenth National Shade Tree Conference Proceedings, 1939: 112. Wells, B. W. and Schunk, I. \., 1938: "Salt spray an important factor in coastal ecology." Bui. Torrey Botanical Club, Vol. 65: 485. NOTES ON THE SMALLER EUROPEAN ELM BARK BEETLE^ Scolytus mullistrialus Marsham Philip Wallace I^BSERVATiONs are reported on the biology of Scolytus multistriatus ^-^ Marsh, as it occurs in Connecticut, with particular reference to its relation to Dutch elm disease. These investigations have been conducted cooperatively by the Entomology and Forestry Departmenls of this Station. The spread of Dutch elm disease in llie United States is due chiefly to the transmission of the fungus, Ceratostomella ulmi (Schwarz) Buisman, by the lesser European elm bark beetle, Scolytus multistriatus Marsh. (Collins, C. W. 1938). The adults are known to carry spores of the fungus from diseased elms, and to innoculate healthy elms when feeding on the bark and wood of small twig crotches, or when boring through the bark and attempting to breed in live elm wood. Infection does not take place unless the spores of the fungus are deposited in the vessels of the sapwood, and then only under favorable moisture and temperature conditions. Early records and geographical distribution. Scolytus multistriatus Marsh, is common on elms throughout central Europe and has been known to occur there for many years. The earliest record of this beetle in the United States was made by Chapman (1910). He fomid S. multi- striatus at Cambridge, Mass., in 1909, and stated that it undoubtedly had been introduced many years previously. In subsequent years intro- duction of this European elm bark beetle took place at several Atlantic ports and in several localities in northeastern and midwestern United States, near veneer mills which handled European elm burl logs, along railroads known to have carried such logs, and at points to wliich other infested elm material was known to have been carried. C. W. Collins (1938) gave a detailed report of the distribution of -S. multistriatus in the United States. He stated that its occurrence is limited to sections of the following states: New^ Hampshire, Massachusetts, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, West Virginia, Ohio, Indiana and Kentucky. ' The writer wishes to express his appreciation to the following persons; Mr. W. O. Filley, Station Forester, and Dr. R. B. Friend, under whose guidance these investigations were carried on; Dr. Raimon Beard for assistance in held work and in the preparation of this paper; Mr. B. W. McFarland, who did the photographic work, and agents of the U. S. Department of Agriculture who co-operated in bark beetle trap studies. 294 Connecticut Experiment Station Bulletin 434 The first record of this insect in Connecticut was made in 1932 by Felt, who mentioned its recent discovery in Stamford. Figure 2 is based on a recent survey which indicated that in this State Scolytus multistriatus occurs in most of the towns west of the Connecticut River, and in East Hartford, Glastonbury, and Manchester, east of the river. It appears to be increasing in numbers and slowly spreading eastward, but there has been no spread into northeastern Connecticut from the early infestation near Boston. The heaviest infestations occur in Fairfield and lower New Haven counties. The hurricane of September 21, 1938, appears to have had little influence on the distribution of this beetle in Connecticut to date. The S wultislrialui INFESTATION IN CONNECTICUT Q SPREAD DURING 1939 PREVIOUS TO 1939 Figure 2. excessively high winds, which might have carried any insect long distances, occurred when the flight season for these beetles was practically terminated, and a clean-up of elm wood in the previously heavily infested towns pre- vented an increase to outbreak proportions the following season. Host plants. This insect attacks all the species of elms within its range in this country and is reported to attack practically all the species in Europe. It is not reported from any other host than the genus Ulmus in the United States, but in Europe it has been recorded (Escherich, 1923 ; Nunberg, 1930) from aspen, ash and plum. The Smaller European Elm Bark Beetle 295 Life Cycle Chapman (1910) gave the first account of the biology of 5. multistriatus in this country. In 1935 Readio pubUshed a more complete account which agrees in most details with the observations here reported. C. W. Collins, et al. (1936) made further additions to our knowledge of the biology and habits of this insect. EMERGENCE of S mu/f/s»nofus ADULTS 1939 =»ST GENERATION 1 SECOND GENERATION 1 1 L LIFE CYCLE ol Sco//ruswtj/ristr'OfusUAns» Figure 3. In southern Connecticut the first adults emerge during the latter part of May, when the elm leaves are about two-thirds developed. The record of emergence indicated in Figure 3 was made from infested logs placed in emergence cans from which the beetles were removed daily. These cans were bottomless, placed directly on the soil, covered with two layers of 296 Connecticut Experiment Station Bulletin 434 black cloth, and kept in partial shade. Figure 3 diagrammatically repre- sents the life cycle of S. mullistriatus. In 1939 emergence of the first generation adults began on May 24, was at a peak on June 6, and was complete on July 10, a few days before the second generation adults appeared. Eggs of the first generation are deposited from one to 10 days after the adults emerge, and were noted from May 27 to July 15. The peak of abundance occurred about June 9, shortly after the peak of adult emer- gence. The first generation eggs began to hatch and larvae emerged on June 3. Larvae from these eggs were most abundant about July 17. It was observed that about 4 percent of the first generation larvae did not transform the same season but had what may be termed a diapause and hibernated as larvae. This phenomenon was noted by Becker (1937) in the case of Hylurgopinus rufipes Eichh. Pupation of first generation larvae was noted on July 8 and the peak was reached about August 10. Pupae continued to develop throughout the summer until cold temperatures prohibited further activity. Emergence of second generation adults commenced on July 12, reached the peak of abundance about the middle of August and continued until September 24. However, occasional adults were noted in the field somewhat later than this. Eggs of the second generation appeared on July 15 and were most abundant during the middle of August. Eggs were observed throughout the early fall. The second generation of larvae commenced to hatch during the third week of July and became more abundant until the eggs were killed by cold in early October. These larvae and a few of the first genera- tion larvae are the only stage of this insect which hibernate. By the middle of October the adults, eggs and pupae are all dead and the larvae are inactive within the bark. As soon as the temperature becomes warm enough in early May, the larvae begin to feed again and complete their development. This period may last until early July. Pupation of the overwintering larvae begins during the middle of May and ends about the first week of July. There are ordinarily two complete generations of this insect in Con- necticut, although often there is one and a partial second, and occasionally only one. It has not been determined whether or not this aberrant behavior of some individuals to produce only one generation is an hereditary char- acteristic. Of 1,851 emerging adults, 901 were males and 950 were females, giving a sex ratio of .51, almost an even proportion with no significant difference. Habits Feeding of adults. Some of the emerging adults feed for a few days on the bark and wood of healthy elms, usually at small twig crotches. Fransen (1931) stated that this period of feeding lasts from 7 to 10 days. An excellent description of the injm'ies caused by adults feeding in twig crotches is given by Wolfenbarger and Buchanan (1939). The adults bore into the center or slightly to the side of a twig crotch, excavating a The Sn alter European Elm Bark Beetle 297 small oval hole, somewhat greater in width than the diameter of the beetle, and slightly greater than the beetle in length. Extensive feeding scars measure 5 mm. in length, 2 mm. in width, and are 1 mm. below the surface, according to C. W. Collins, et at. (1936). Sometimes the adults burrow under bark scales at nodes or into depressions left by cladoptosis. When the attack is severe many twigs are completely girdled and hang from the branches like oak twigs attacked by the oak twig girdler, Oncideres cingu- latus Say. While making the burrow small pieces of bark and frass are thrown out but rarely is any attempt made to construct a brood gallery. It can be assumed that the only purpose of these burrows is foi feeding. The investigations of Wolfenbarger and Buchanan (1939) substantiate this hypothesis. They found that newly emerged S. mutti- striatus adults lived a significantly longer time when caged with elm twigs upon which they appeared to feed, than did those without food or water. Observations in 1939 indicated that only a small percentage of the adults feed on elm twigs at any time. This feeding may occur near the place of emergence or near the place where brood galleries are to be formed. Elm logs infested with S. nuiUistriatiis lao'^ae were placed in a pile at one end of a row of elms, 10 to 25 feet in height, and a pile of freshly cut elm logs was placed 250 feet away, at the other end of the row. At each 25- foot interval from the infested logs, 1,000 twig crotches were marked for observation. A cursory examination of these crotches was made weekly for evidence of beetle feeding, but none was found until a thorough inspec- tion was made after emergence from the logs was complete. It was pre- viously determined that no other infested elm, nor elm material attractive for beetle breeding, existed within a half-mile radius. The total number of beetles vshicli emerged from these logs, as indicated by the emergence holes, was 2,898. Twig crotch attack was very light and of little conse- quence more than 25 feet from the place of emergence (Table 30), and no indications of feeding were observed more than 75 feet away from the infested logs. Three feeding scars found 200 to 250 feet distant were pre- sumably attacks at the place of breeding, although no brood galleries of aS. multislriatus were formed in the fresh elm logs which were used to attract them. Table 30. Crotch Feeding Near Place of Emergence Diatance from Crotches Feeding Percent crotches infested logs observed scais attacked 0— 25 feet 25— 50 " 50—100 " 100—125 " 125—150 " 1.50—175 " 175—200 " 200—250 " 1,000 13 1.3 3 .3 3 .3 0 0 0 0 0 0 0 0 3 .3 Total 8,000 298 Connecticut Experiment Station Bulletin 434 Observations were made at two heavily attacked trap piles to deter- mine the intensity of S. multistriatus crotch feeding around attractive breeding material. The elm logs constituting the traps were barked and 4,932 egg galleries found. Assuming there was one male and one female for each gallery, there must have been 9,864 beetles attacking these two trap piles. The density of the egg galleries was 21.1 per square foot of bark surface. This may be considered very close to the maximum density of 5. multistriatus egg galleries to be found in such breeding material. From a tabulation of the egg galleries made in the logs of 81 trap piles it was found that in only one trap did the average density of egg galleries exceed 20 per square foot, i.e., 27.8. Table 31 is the record of observations made around these log traps. Table 31. Crotch Feeding Near Place of Attack Distance from trap pile in feet Crotches counted Feeding sears % Crotches attacked Trap No. 12 0— 6 6—15 16—20 20—30 638 964 608 241 51 17 1 0 8.0 1.7 .16 0. Trap No. 13 0— 6 6—15 209 694 15 22 7.1 3.1 Total 3,354 106 3.1 These observations of feeding at the place of emergence and at the place of attack are obviously not comparable, and furthermore should not be used as a correlation of abundance. The results do indicate that the beetles feed near breeding material as well as near the place of emergence and that feeding is negligible any great distance fromeither of these loca- tions. This is important from a standpoint of cleaning up breeding material. In the insectary it has been demonstrated many times that emerging adults do not need to feed on twigs or other material before commencing the brood tunnel. Many adults, when taken directly from emergence cans and caged with a freshly cut log, begin to burrow through the outer tark at once, and occasionally have been observed to excavate as much as 7 mm. of the egg gallery and deposit five eggs within 24 hours after emergence. It appears that twig crotch feeding is quite variable. The intensity of such feeding either at emergence or attack may depend on weather con- ditions and other factors beyond our present knowledge or control. Breeding material and attack. The characteristics which make certain elm wood attractive or unattractive for elm bark beetle breeding are at present not entirely understood. This beetle prefers to breed in dead, dying, or devitalized elm wood, although all such material is not The Smaller European Elm Bark Beetle 299 attacked. Trees affected with Dutch elm disease apparently often develop a certain physiological condition which makes them particularly favorable breeding centers. Observations of the intensity of crotch feeding near breeding places indicate that presumably the individual attractiveness of certain trees is an important consideration, as well as the location of the elms in reference to the source of the beetles and to the breeding material itself. The size of the material is not a limiting factor in breeding, for trunks of elms 70 inches in diameter and half-inch twigs have been observed heavily attacked in certain instances. Moreover, we have noted successful emergence from limbs .5 inch in diameter. If a certain portion of a tree is more heavily attacked than the rest, it can only be assumed that at the time of attack that pai't was more attractive to the bark beetles seeking breeding places. Observations of an elm, 10 inches D.B.H., which was completely cut off at the base and left standing at the time when beetle flight was at its peak, indicated that for this tree there was no correlation between height from the ground or diameter of the parts (except for branches less than 1 inch in diameter) and severity of attack. A great abundance of beetles in an area sometimes results in a con- spicuous attack on material ordinarily unaffected. We have recently observed an elm in full leaf and apparently healthy, being attacked by S. mullistriatus adults. This occm-red in a heavily infested area, on poor soil, during a period of drought. Attack has also been noted on elms the roots of which were flooded, and in the dead or dying area surrounding a wound or a nectria canker. Occasionally unsuccessful attempts to attack elms are noted in which the flow of sap was so great that it either forced the beetles to back out or killed them in situ. Such cases are common in elms, overthrown by the recent hurricane, which still retain many roots in the soil, but at one time were close to death from lack of soil moisture. The adult, usually the female, chooses a point of attack on a log in suitable condition for breeding, but no attempt is made to start a brood tunnel in such a position that the subsequent larvae will have space to move about and feed. In cages the beetles apparently prefer to start the gallery at the end of a log, and even though infestation is not heavy, parallel egg galleries may be observed as close as 5 mm. apart. Having chosen a point for attack, the adults at once commence excavating an entrance burrow. It is directed inward, and in vertical logs or trees is situated at the lower end of the egg gallery and directed slightly upward. The entrance burrow extends through the inner bark, usually scoring the xylem. It is slightly over one mm. in diameter, and may be distinguished from an exit hole by its somewhat smaller size, the reddish-brown frass surrounding it, and its general location at the edge of a flake or ridge of bark. A turning or nuptial chamber is then excavated. This is about 3 mm, long and 1.5 mm. wide, and usually meets the egg gallery at an oblique angle. Chamberlain (1939) considered that monog- amous species use this chamber for turning only and that mating takes place only once. Mating. Our observations of mating are restricted to a few pairs of beetles which were noted in copula when taken from emergence cages. 300 Conneclical Experiment Station Bulletin 434 Chapman. (1910) stated tiiat copulation first takes place at the entrance to the burrow after two to five days of characteristic behavior, from which time on the male works with the female in egg gallery excavation. He believed they mate several times thereafter. This species is monogamous and a pair constructs only one egg gallery. Observations by C. W. Collins, et al. (1936) indicated that whenever the female remains for some time at the gallery entrance, the butting activities of the male are accelerated. Suddenly the male reverses his position and copulates with the female. They immediately re-enter the gallery, the male entering backwards, where coition is presumably consummated. In order to obtain more information regarding mating, females were taken soon after emergence and caged with logs for breeding. The only time they had an opportunity to be with the males was the few hours between the time they emerged and the time when they were removed from the emergence cages. As shown in Table 32, these females, without further contact with males, excavated egg galleries of somewhat less than normal length and deposited fewer eggs than normal, but these were of average fertility. This indicates that mating may take place immediately after emergence. It is not apparent whether the shorter galleries and fewer eggs are due to restricted mating or to an overburden of work for the female. Table 32. Egg Galleries by Females Without Contact with Males after Emergence Cage Length No. Eggs mm. Eggs hatched No. 1 2 3 4 5 6 7 Average 19.7 23.8 91.6% % of Normal 70.0 34.7 95.4 When males alone were caged with logs, in all cases in which the male did not quickly die an egg gallery was excavated in the ordinary manner, but the galleries were short and no egg niches' were excised. The egg galleryi After excavating an entrance burrow and nuptial chamber, the female precedes the male and begins the egg gallery. This is usually constructed parallel with the grain of the wood, although many have been noted at a 45 degree angle with the grain, and occasional galleries run directly across the grain. The female does most of the actual excavation with the male usually close behind. They both enter head forward. The female pushes the boring 21 42 42 20 42 39 19 33 32 10 4 0 34 20 17 23 10 9 11 16 14 The Smaller European Elm Bark Beetle 301 dust backwards with the mandibles and fore-tibiae, working it past the body with the legs and by rotating the body. The male, in turn, pushes the dust backwards until it is finally ejected from the entrance burrow. Ordinarily great care is taken not to let frass accumulate in the egg gallery. Usually, the female penetrates to the xylem and constructs a nuptial chamber within 24 hours after attack, but the time required varies con- siderably. In the extreme cases of seven egg galleries, 24 hours after exposure to attack by beetles direct from emergence, the average length was 5.1 mm. In other instances three or four days are required to pene- trate to the cambium. We were unable to observe the activity of the adults by shaving down the bark and placing a glass plate over the egg gallery, as described by Swaine (1918) for observing Dendroctoniis beetles. Furthermore, the method of clamping a piece of bark against a glass plate which was used by Kaston (1939) for rearing and observing the larvae of Hylurgopinus rufipes is not satisfactory for observing the activities of the adults or larvae of S. muUistriatus in the egg gallery, because the packing of frass along the gallery and against the glass often obscures their activities. The observations noted herein were made in the following manner. Adults direct from emergence were placed in a cage with a freshly cut elm log. After 24 hours' exposure to attack, a section of bark about 6 inches square was raised at four places on the log. At each point where an adult had penetrated the bark flap, a designating number was scratched on the inner bark. The bark was then replaced and held down with two wires about the log. In this manner daily observations were readily made on egg gallery construction, oviposition, and hatching. Care must be used not to crush nor disturb the adults when replacing the flap, and it is also important each time to tighten the wires about the flap in order that it may be in close contact with the wood and lose as little moisture as possible. In the construction of 36 egg galleries observed daily, the average length excavated per day was found to be 3.21 + .1 mm.^ The average length of 311 completed egg galleries was 28.2 + 2.1 mm. The maximum was 83 mm. and the minimum 12 mm. It might therefore be assumed that about nine days are required for the construction of an average egg gallery, but a period of cold or wet weather markedly retards activity. However, adults often remain active in the tunnel two or three weeks after attack. Oviposition. Commencing about 1 mm. from the nuptial chamber, the female cuts out niches on both sides of the gallery wall. These are slightly larger than the egg and under optimum conditions are spaced very closely so that only a thin film of wood fiber separates them. In 197 egg galleries with a total length of 5,471 mm., 13,485 eggs were de- posited. The maximum number of eggs deposited in a completed gallery was 227 and the minimum was 17. The average per gallery was 68.5 ± 1.6. Of these 95.9 percent hatched. The average number of eggs per millimeter, computed from the average number of eggs deposited and the average length of a gallery, was 2.46. Actually the eggs are slightly ' Reference is made to the standard error. 302 Connecticut Experiment Station Bulletin 434 closer together than this indicates because the female sometimes does not deposit an egg in every niche nor use all the available space on the sides of the gallery. The female proceeds backward to the niche, slightly raises the abdo- men, and an egg suddenly appears in the space. She immediately gathers some frass and packs the egg in tightly, using the fore-tibiae and mandibles. Usually only a small, shining tip of the egg can be seen from the inner side of the bark, but sometimes the egg is entirely invisible. Only one egg is deposited in a niche, and generally the oviposition lags somewhat behind the egg gallery excavation. The female may cut niches and deposit eggs as fast as the gallery is constructed, but she often goes back after a period of excavation, cuts niches, and deposits an egg in each. Developmental Stages The egg. The egg is shining white, subspherical, about .6 mm. by .4 mm. The surface is regular and unsculptured. The eggs cause no pro- tuberances in the gallery for they are packed in flush with the gallery wall. In a few cases it was noted that fertile eggs were deposited within 24 hours after emergence of the adults. In other instances five days were required before oviposition took place. In 45 egg galleries observed, the average time between exposure to attack and oviposition was 2.68 ± .2 days. The total number of eggs deposited per tunnel is subject to considerable variation. Unfavorable weather slows down oviposition and diminishes this total. If the sap flow in the bark becomes too great, or if the bark dries out too quickly, the adults may leave or die in the gallery, although the eggs already laid may hatch. Apparently the presence of a male in the gallery has a salutary efi'ect on egg deposition. More than one mating may be necessary to fertilize a large number of eggs, and the male also relieves the female of much of the work in disposing of the frass. Egg galleries excavated in September are often shorter and contain fewer eggs than those made when high temperatures are more continuous. According to Wadley (unpublished laboratory notes, 1934, ref. Collins et al., 1936) Scolytus multistriatus is inert at 45 degrees F., crawls at 52 degrees F., flies at 70 degrees F., and is vigorously active at 85 to 90 degrees F. This may explain the fewer eggs and shorter galleries noted late in the season. From daily observations of oviposition during warm weather it was found that an average of 3.7 + 1.1 eggs were deposited per day. Occa- sionally no eggs were deposited for a day or more, and the maximum noted was 14 in one day. The incubation period for the eggs does not vary greatly except under adverse weather conditions, and hatching occurs in surprisingly direct sequence with the time at which the eggs were deposited. From observa- tions of 507 deposited at known dates during August, the average length of the incubation period was found to be 5.1 + .5 days. The maximum noted was nine days and the minimum was three days. About 24 hours before the shell breaks open, the egg loses its shining appearance and shrinks slightly. At this time, if the egg shell is carefully opened, the tiny larva, completely formed, may be removed. The Smaller European Elm Bark Beetle 303 Figure 4. Smaller European ekn bark beetle: Center above, female, lateral view, about 23 times enlarged. A, left tibia, posterior aspect; B, left antenna, lateral aspect; both enlarged 76 times; C, head of male, lateral aspect, enlarged 23 times; D, larva; E, head capsule, dorsal aspect; F, caudal segments, ventraJ aspect; G, pupa, ventral aspect. 304 Connecticut Experiment Station Bulletin 434 Larval period. The larva is scolytoid in form, creamy white and 3.5 to 4 mm. in length when fully developed. A fold in the integument, straight across the posterior half of the pronotum and terminating in a puckered depression on each side, readily distinguishes this larva from Magdalis sp., in which the fold is distinctly arcuate, and from H. rufipes larvae in which the characteristic fold and musculature are not readily discerned. The very sparse pubescence on the venter of the thoracic segments is an additional characteristic by which »S. multistriatus larvae may be distin- guished from other scolytoid larvae found in elm. When the egg shell breaks open the larva may be seen from the inner sm'face of the bark, wriggling about within its shell. During the next 24 hours the larva commences to feed and excavates a tunnel at right angles to the egg gallery. The first few millimeters of the larval tunnel are usually excavated entirely within the phloem, and the larva is not then visible. Very shortly the larva cuts entirely through the inner bark, and although the main part of the tunnel is within the bark, the sapwood is lightly scored throughout the length of the larval tunnel. As the larva proceeds, molts, and increases in size, the tunnel is correspondingly larger and may be 2 mm. in width after several ecdyses. Readio (1935) stated that there are five larval molts. The larval tunnel is tightly packed with frass and excrement and occasionally parts of larval exuviae may be found in the mass. As the larval tunnels are extended they diverge, forming a char- acteristic fan-shaped pattern. Larvae hatching from eggs at the ends of the gallery usually tunnel with the wood grain, parallel to the egg gallery. Occasionally in a heavily populated area the larval tunnels may cross and recross or two larvae may follow the same tunnel. The length of larval galleries from which adults have emerged varies greatly. The longest noted was 73 mm. and the shortest was 12 mm. The average length of 454 larval tunnels was found to be 36.5 + 1.2 mm. A short time before the larva pupates, it enlarges the end of the tunnel and constructs a bai'e cell, continuous with the larval tunnel and often at a right angle to it. This pupal cell is entirely within the bark, not visible from the inner side, and often contiguous to the underside of a flake of outer bark. Ordinarily these lai'vae are able to withstand extreme moistme condi- tions. Many within logs which remained indoors against a steam radiator for two weeks pupated and emerged without apparent ill effects. No detrimental effect on larvae within logs was observed when the logs were submerged for two months in the salt water of an ocean inlet. After sub- mersion for four months, the logs froze in the ice and when removed three weeks later about 50 percent of the larvae were alive and some developed to adults in the laboratory cages. This observation concm's with that of Collins et al. (1936), who found that these larvae can withstand two months" submergence in tapwater. Obviously the distribution of this insect may be influenced by the movement of infested logs along inland streams and coastal waters. Pupal period. The pupa is shining white and bears two distinct appendages on the caudal segments of the abdomen. The duration of the The Smaller European Elm Bark Beetle 305 piepupal and pupal stages was determined at 27 degrees C. in an incubator in which an open dish of water was placed to maintain proper humidity. The larva passes through a prepupal period of about 36 hours. During this time it is quiescent and the contents of the alimentary tract are voided. The average duration of the pupal period was 5.0 + .6 days. Collins et al. (1936) found that the hibernating larvae required two days for the prepupal stage and that the pupal stage lasted 10 days or more under natural conditions during May. Readio (1935) reported a prepupal period of one or two days and a pupal period of five to six days at 27 degrees C During the latter part of the pupal period the light color of the pupa slowly darkens, so that when transformation is complete the adult is light brown in color. Emergence of adult. The adult beetle is 2.3 to 3 mm. in length. The pronotum is shining black and finely punctured and the elytra are shining reddish brown, distinctly striate and feebly but densely punctured. A spine projecting from the upper part of the second ventral abdominal segment aids in distinguishing this beetle from many other scolytids. After the adult becomes somewhat hardened, it cuts its way through the outer bark to the surface and crawls about for a short time before flying away to feed or seek a place to breed. The emergence holes are round and slightly larger in diameter than the beetle. The frass from these holes is packed into the pupal cell and does not appear on the outer bark around the holes as it does about entrance burrows. Flight and Wind Dispersion No precise observations have been made relative to flight or wind dispersion of these beetles, but the importance of these factors cannot be overlooked. Certain data have been obtained on the movement of insects of similai" type and it is reasonable to assume that they may apply in part at least to the movement of 5. muUistriatus. Felt (1935) stated that the closely related hickory beetle, Scolylus quadrispinosus Say, was taken in Albany, N. Y., in 1927, on a roof top 125 feet above the sidewalk, well above adjacent tree tops, and fully three- quarters of a mile from any hickories. At the same location he also re- corded taking three species of pine bark beetles, Ips callipraphus Germ., Ips grandicollis Eichh., and Ips pini Say, which must have drifted or flown more than a mile. In the same paper Felt made available data from the Federal Bmeau of Entomology, recording the capture from an aeroplane of two species of Xylehoriis at an elevation of 2,000 feet, another species at 500 feet and four other species of scolytids at 200 feet. The importance of wind drift and air currents in relation to the dispersion of Scolylus mulfislriatus is fm'ther emphasized by Felt (1937) from reports of balloons released in southwestern Connecticut, New York and New Jersey. He stated that wind carriage of infected beetles affords the most reasonable explanation of the distribution of Dutch elm disease in the Northeast. However, this work was done before the disease spread southward through southern New Jersey and westward from New Jersey into eastern Pennsyl- vania. It may well be that natural barriers, availabihty of breeding mate- rial, and climate render insignificant the general efi'ects of the prevailing winds and upper air currents in the distribution of this beetle. Although 306 Connecticut Experiment Station Bulletin 434 doubtless wind drift occurs and may be responsible for some outlying infestations, transportation of beetle-containing material appears more significant. Observations of breeding habits lead us to believe that under ordinary conditions flight of S. multislriatus is usually limited to about one-quarter mile. The stimulus for flight is considered to be the desire for suitable breeding material rather than for food, and the beetles appear to be attracted to the nearest suitable elm wood, as observed by Kaston (1939) in the case of the native elm bark beetle, Hylurgopinus rufipes Eichh. Previous to the hurricane of September 21, 1938, the limits of the distribution of S. multislriatus in Connecticut were fairly well known. Although there was a heavy infestation around New Haven, North Haven, North Branford and Branford, no evidence of this beetle could be found east of Guilford during a careful survey in the summer of 1938. Much of the hurricane-elm material in these towns and in Guilford was destroyed by the U. S. Department of Agriculture and other agencies, before beetle emergence in July, 1939, but a heavy infestation still existed in Branford and North Branford, if the degree of attack on trap logs may be used as a criterion. After the emergence of the second generation, inspection was made of enormous quantities of elm wood in the towns along the Con- necticut shore, east of Guilford, where little effort has been made to destroy it. In this group of towns the only evidence of S. multislriatus was a light infestation in Madison, the town adjoining Guilford on the east. This beetle was recorded from Guilford in 1936 and was found there in fairly large numbers in 1937 and 1938, so the abmidance of elm-breeding material there during 1939 may have had little significance this season. Occurrence of the beetle this year in Manchester, Durham, Middlefield, Cheshire, Cromwell, Seymour and Berlin appears to be a parallel of the situation in Madison, for our investigations indicate that the spread prob- ably came from adjoining towns. A light infestation in Saybrook is believed to be the direct result of transportation of elm logs from the infested area. Figure 2 indicates the distribution of S. multislriatus in Connecticut and the spread in 1939. During the flight periods in 1939, there was an enormous amount of elm material available throughout Connecticut and much of it was in a suitable condition for breeding at all times. It is probable that the broken, uprooted and dying elms resulting from the hurricane will continue to offer suitable breeding material for these bark beetles for several more years, and that they will eventually spread to every locality in Connecticut where breeding places are maintained. Apparently the normal spread is quite slow, even with an abundance of suitable material present. Parasites and Predators The general effect of parasites and predators on S. multislriatus is little known. Field observations indicate that in some localized areas certain elm bark beetle enemies are present in great numbers and un- doubtedly are important in reducing the beetle population. Two hymenopterous parasites of Scolytus mullistriatus are known and both have been taken in Connecticut. Spathius canadensis Ashm. has The Smaller European Elm Bark Beetle 307 been recovered in large numbers, and Cheiropachys colon Linn, has been taken less commonly. A nematode parasite, Paras itylenchus scolyti Oldham, is reported by Oldham (1930) to attack Scolytus miiltistriatus and render as many as 60 percent of the brood sterile. The clerid, Enoclerus nigripes Say, is a common predator as adult and larva upon all stages of *S. multistriatus. The clerid eggs are deposited in the entrance burrow, whence the larvae make their way throughout the bark beetle egg gallery and larval tunnels, devouiing every host egg, larva, and pupa which they are able to reach. The adults are as voracious as the larvae and move rapidly over the surface of an infested log devouring every bark beetle in sight. The clerid attack upon a brood of emerging S. multistriatus adults is an astounding procedure to watch. It is difficult to evaluate the activity of birds in bark beetle control. The downy woodpecker, Dryobates pubescens medianus Swain., and the hairy woodpecker, D. villosus villosus Linn., are by far the most common bird predators of S. multistriatus in Connecticut. A woodpecker has been observed going methodically around a limb of an infested elm, tearing off small strips of bark and devouring the larvae as fast as it could proceed. Woodpeckers have also been observed picking out the adults as they com- menced to attack a decadent elm. In certain swamp areas the top limbs of nearly all the infested elms appear to have the bark shredded and a large proportion of the larvae were found to have been destroyed. Although the effect of birds is sometimes locally significant, it is believed that the important species are not numerous enough to exert any appreciable in- fluence on the European elm bark beetle population in general. The mycelium of an undetermined fungus is often found in association with dead larvae, pupae and adults within the bark, but its significance is unknown. Bark mites are often numerous within the egg galleries and larval tunnels of 5. multistriatus but their effect on the brood has not been studied. Rust (1933) found that mites destroy an approximate average of 50 percent of some bark beetle broods, and that 15 to 85 percent of the eggs of Ips oregoni Eichh. in ponderosa pine are devoured by predaceous mites. Survival of Larvae at Low Temperatures Recent observations on the effect of low temperatures on the survival of larvae of S. multistriatus indicated that while most naked larvae die when exposed for a short time to temperatures below -8 degrees F., some survived as low as -70 degrees F. Mortahty of larvae contained in logs and exposed for various periods to constant low temperatures shows trends which cannot be strictly correlated with duration or intensity of cold alone. It is believed that winter temperatures in Connecticut are responsible for little mortality of these larvae. Artificial Control There is scant information relative to the artificial control ^of this bark beetle which is based on field tests. The subject has been considered on the basis of what is known of the flight, feeding habits, and life history of the insect. 308 Connecticut Experiment Station Bulletin 434 Destruction of breeding material. The most obvious control measure consists of removing elm material which may provide attractive breeding places for the beetles, and the destruction of infested elm material. Investigations by D, Collins (1938) indicated that there is a definite correla- tion between the presence of beetle-producing or beetle-attracting wood and the occurrence of twig crotch feeding, and that such feeding is negligible more than 1,000 yards from breeding material. Field observations in Connecticut further support this conclusion, but evidence of crotch feeding has not been found here more than 200 yards from beetle-attracting or -producing wood. These observations indicate an entirely feasible program for the protection of valuable elms from bark beetle attack and the possible intro- duction of the Dutch elm disease fungus. Spraying. Various sprays containing poisons, repellents, and fungicides have been tested at several experimental laboratories. Complete reports are not available, but Felt and Bromley (1938) observed a reduction in intensity and depth of feeding on small potted elms, caged with a large number of beetles, when sprayed with lead arsenate and a sticker. A preliminary report by D. Collins (1938) indicated that in general the feeding on sprayed, caged elms was less than on un sprayed. He further observed that under natural conditions crotch feeding is so erratic that it is difficult to evaluate the results obtained in controlled experiments. It is apparent from the evidence reported that none of the materials tested are likely to give satisfactory control when applied to large elms in the usual manner, even with the current high-pressure spraying equipment. Chemical treatment of breeding material. Various chemicals were applied to the surface of bark beetle breeding material in an attempt to render it unsuitable for attack. After preliminary tests a light coal-tar creosote oil was selected. Extensive laboratory and field tests indicate that this material, when applied to the bark of elm, may render such logs permanently unattractive for bark beetle breeding. When applied to logs containing bark beetle larvae, the penetrating and killing effects have so far not been entirely satisfactory. In connection with a pruning project during the summer of 1939 in an infested area, the dead and dying wood pruned from about 700 field and woodland elms was treated with creosote. A random inspection of this material in October revealed that there had been no bark beetle attack to any of the treated logs. Creosote was carried in the field in a 12-quart pail and applied with a 4-inch paint brush. This creosote is obtainable from producers of illuminating gas at about 20 cents per gallon in 50-gallon drums, and is,known to the trade as "light creosote oil". The bark from 20 treated logs was burned in a pile about two months after application, and the odor of creosote was hardly noticeable. Appar- ently there is no reason why logs so treated might not be used for fuel. The application of creosote causes the bark to dry rapidly so that by the time the odor is dissipated to such an extent that it might no longer repel bark beetles, the bark is so dry and loose that it is entirely unsuitable for beetle breeding. The Smaller European Elm Bark Beetle 309 Trap logs. Trap logs have been tested for many years in attempts to reduce the infestation of various species of bark beetles, but the results have generally been obscure or unsatisfactory. Fluctuations in the density of beetle population may be due to factors entirely removed from trapping. Data from obsei-vations of 81 trap piles of elm logs placed at various points in southern Connecticut substantiate the conclusion of Martin (1936) that logs in semi-shade are most attractive to S. miilti- striaius. It was also noted that bark beetles seldom breed in the top quadrant of an elm log in any exposure. Emergence of Hylurgopinus rufipes adults from hibernation takes place during late April and early May (Kaston, 1939), before the emergence of S. mullistriatus. It has been found that trap logs placed during this period often serve as breeding places, not only for the H. rufipes adults then in flight, but for those adults often found hibernating at this time in the bark of the trap logs. S. mullistriatus adults emerging in late May and June were thus excluded from breeding in many trap logs which were placed in April and May because they were already infested with H. rufipes. An indication was desired of the effect of trapping of first generation adults on the subsequent density of population of the second generation. FoUowmg a comprehensive trapping program by the U. S. Department of Agriculture for the adults emerging from hibernating S. muJtistriatus larvae, similar traps were placed at two of the previous locations after the first generation emergence was complete and the pre\nious traps had been removed. The number of egg galleries formed per square foot of surface by the second generation was not significantly difi^erent from that of the first generation. These observations M^ere hmited and may not represent the actual beetle population, but they suggest a factor to be considered — availability of breeding material. Scrutiny of the small quantity of elm bark beetle breeding material in the area indicated that everywhere infestation was close to the maximum, and that under any conditions this material could have accommodated only a small percentage of the emergmg adults. It is suggested that the first generation adults which were trapped and destroyed, were a part of those which would have died inevitably from a scarcity of available breeding wood. The density of beetle population within an infested area fluctuates so rapidly due to ecological factors and to the aA"ailability of breeding material in particular, that it is beheved extensive research should precede the general use of traps to reduce elm bark beetle population. Summary S. mullistriatus, a native of Europe, was first reported in this country at Boston in 1910. Since that time it is known to have been introduced and become established in many sections of northeastern United States. Figure 2 indicates its distribution in Connecticut. All species of elms planted in this part of the country are subject to attack, and it is reported from practically all the species of elms in Europe in addition to aspen, ash and plum. There are ordinarily two complete generations of this insect in Con- necticut, although there is often one and a partial second generation and, occasionally, only one complete generation develops. Hibernation takes 310 Connecticut Experiment Station Bulletin 434 place ill the larval stage only. The first generation adults commence to emerge from hibernating larvae during the latter part of May. Oviposition takes place within a few days. The first generation larvae commence to pupate during the second week of July and second generation adults appear very shortly after the emergence of the first generation is complete, about the middle of July. All stages of the insect may be observed through- out the summer but activity ceases by the first of October. Some of the adults feed in the twig crotches of healthy elms for a few days shortly after emergence. This feeding may occur near the place of emergence or near the place of attack, and has not been observed more than 200 yards from either of these locations. Many adults do not feed in this manner but go directly to breed. This attack on elm twigs is quite variable and has indicated no correlation with factors other than distance from breeding material. Mating may occur within a few hours of adult emergence before the beetles move away or at the entrance burrow of the new egg gallery. This species is monogamous, constructs only one egg gallery, and is suspected of mating more than once. The average length of egg galleries was found to be 28.2 mm. and the average number of eggs deposited per gallery was 68.5. The presence of a male in the gallery appears to stimulate the female to increased egg pro- duction. An average of 3.7 eggs were deposited per day in the galleries noted. The larvae ordinarily are able to withstand extreme moisture condi- tions. It is considered that natural barriers, availability of breedmg material and climate render insignificant the effects of prevaihng wmds and upper air currents, in the distribution of this insect. The hurricane of September, 1938, appears to have had little influence on the dispersion of this bark beetle in Connecticut during 1939. Observations on the effect of low temperatures on survival of the larvae of S. multistriatus indicate that the factors of cold intensity and cold duration are responsible for little winter mortality in this State. Various parasites and predators are noted but they do not appear to exert enough control to be of importance in an outbreak. The controlling factor in an outbreak of these bark beetles is believed to be the availability of breeding material. The sprays used by various investigators to prevent twig-crotch feeding have so far proved of doubtful value for that purpose. An easy and cheap method of preventing infestation of elm bark beetle breeding material is the application of fight creosote oil to the bark. This has been tested extensively in the field and proven most satisfactory. Experiments with trap logs to reduce beetle infestation indicate that the density of beetle population fluctuates so rapidly within an area due to ecological factors and to the availability of breeding material in particular that it is believed extensive research should precede the general use of traps. Miscellaneous Insect Notes 311 Bibliography Becker, W. M., 1937: "Some Observations on the Larval Instars of Hylurgopinus rufipes in Massachusetts." (Unpublished). Fotuteenth Conference of Con- necticut Entomologists (New Haven). Chamberlain, W. J., 1939: "The Bark and Timber Beetles of North America." Chapman, J. W., 1910: "The Introduction of a European Scolytid (The Smaller European Elm Bark Beetle, Scolytus muUislriaius Marsh.) into Massachusetts." Psyche, 17: 63-68. Collins, C. W., 1938: "Two Elm Scolytids in Relation to Areas Infected with the Dutch Elm Disease Fungus." Jour. Econ. Ent., 31 (2): 192-195. Collins, C. W., W. D. Buchanan, R. R. WTiitten and C. H. Hoffman, 1936: "Bark Beetles and Other Possible Insect Vectors of the Dutch Elm Disease, Cerato- siomella ulmi (Schwartz) Buisman." Jour. Econ. Ent., 29: 169-176. CoUins, Donald L., 1938: "Feeding Habits of Scolytus muUislriaius Meush. with Reference to Dutch Elm Disease." Jour. Econ. Ent., 31 (2): 196-200. Escherich, K., 1923: "Die Forstinsekten Mitteleuropas." 2: 494. Felt, E. P., 1932: Proceedings of the Ninth Annual Conference of Connecticut Entomol- ogists (New Haven), p. 31. (Unpublished) Felt, E. P., 1935: "Bark Beetles and Dutch Elm Disease." Jour. Econ. Ent., 28 (2): 231-236. Felt, E. P., 1937: "Dissemination of Insects by Air Currents." Jour. Econ. Ent., 30 (3): 458-461. Felt, E. P. and S. W. Bromley, 1938: "Shade Tree Insects and Sprays, 1937." Jour. Econ. Ent., 31 (2): 173-176. Fransen, J. J., 1931 : "Enkele gegevens omtrent de verspreiding de door G. ulmi Schwartz veroorzaakte iepenziekte door de iepenspintkevers, E. (S.) scolylus F. en E. (S.) muUislriaius Marsh, in verband met de bestrijding dezer ziekte." Tijdschr. over Plantenz., 37 (3): 49-62. Kaston, B. J., 1939: "The Native Elm Bark Beetle, Hylurgopinus rufipes Eichh., in Cormecticut." Conn. Agr. Expt. Sta., Bui. 420. Martin, C. H., 1936: "Preliminary Report of Trap-log Studies on Elm Bark Beetles." Jour. Econ. Ent., 29 (2): 297-306. Nunberg, M., 1930: (Polish title) Contributions to the Biology of Bark and Cambium Beetles, Polsk. Pismo. Ent., 8: 99-122. Oldham, N. J., 1930: "On the Infestation of Ehn Bark Beetles (Scolytidae) by a Nematode, Paras ilylenchus scolyti n. sp." Journed Helminth., 8: 239-248. Readio, P. A., 1935: "The Entomological Phases of the Dutch Elm Disease." Jour. Econ. Ent., 28 (2): 341-352. Rust, H. J., 1933: "Many Bark Beetles Destroyed by Predaceous Mites." Jour. Econ. Ent., 26 (3): 733-734. Swaine, J. M., 1918: "Canadian Bark Beetles." Dominion of Canada, Dept. of Agr., Tech. Bui. 14. Wolfenbarger, D. 0. and W. D. Buchanan, 1939:" Notes on Elm Twig Crotch Injuries Produced by Scolylus muUislriaius Marsham." Jour. Econ. Ent., 32 (3): 377- 381. MISCELLANEOUS INSECT NOTES The Crazy Ant in Connecticut. In March, 1939, specimens of Paratrechina longicornis Latr. (determined by M. R. Smith) were coUected 312 Connecticut Experiment Station Bulletin 434 in a New Haven hotel. These ants were found in many parts of the building and were causing much loss by infesting food and some annoyance by appearing in large numbers in guest rooms. They were apparently nesting in cracks behind the woodwork and were controlled by systematic use of poisoned baits. According to Marlatt, the crazy ant is a tropical species which has been found in large buildings in various parts of the country. In the New Haven building it had been seen for at least a year prior to identification. [Neely Turner] Dermestid Larvae in Composition Board. Specimens of a Dermestes larva were received in July from a summer cottage near Hartford. These larvae had bored into the composition board used instead of plaster. Eight or ten holes had been made, and larvae were also found underneath a braided rug. The owner was advised that these larvae had developed on some decaying animal matter, and that they had a habit of boring in soft wood to pupate. It was suggested that a possible source of the trouble was a dead animal underneath the cottage, which had no cellar. Within a few days the owner sent the following information: "Following a suggestion in your letter and also because most of the larvae seemed to be near the fireplace, I poked around the chimney with long-handled brushes. Finally I dislodged a hard object from a narrow shelf just back of the damper, which probably was a squirrel. It must have fallen down, suffocated, and then baked hard by the fire, so that we did not realize it was there. Very likely these pests will soon disappear." [Neely Turner! The House Cricket, Gryllus domesticus Linn. A telephone call was received from Dr. Shay of the Health Department, Bridgeport, Conn., requesting information about crickets infesting a home on Birmingham Street in the north end of the city. The home was visited with Dr. Shay and one of his assistants and was found infested from attic to cellar with the house cricket, Gryllus domesticus Linn. It was a new house, built less than a year, and was located within a city block of a dump. Soil covered the debris in the dump which was maintained in such a manner as to leave only the latest material temporarily uncovered. The crickets had been in the house for about two weeks. They had eaten large holes in three dresses, ruining them. More than a hundred that had been killed by a fly swatter were observed. On August 12 a letter was received from a resident of Thorne Street, which is also in the vicinity of the same dump. The writer stated that the neighbors as well as his own family were suffering from an outbreak of crickets in their homes. It was recommended that a poisoned bran bait be used in each case. The formula follows: Wheat bran 5 pounds White arsenic or Paris green 4 ounces Cheap molasses 1 pint Water 7 pints Lemons 1 Miscellaneous Insect Notes 313 The bran bait should be scattered thinly around the places where the crickets are found and outdoors around the home. Domestic animals or birds should not be exposed to any quantity of the bait. If the bait is scattered very thinly, little danger exists for animals or birds. The house cricket was first reported in Connecticut from Shelton in 1918 and only four reports precede the present one in our records. Prob- ably this small outbreak originated in the dump. [J. Peter Johnson] Notes on Asiatic Garden Beetle Damage in a Field of Sweet Corn. On July 7, 1939, a letter received from H. E. Baldwin, Westport, Conn., reported injury to sweet corn seedlings. Enclosed with the letter were two adult beetles which were identified as the Asiatic garden beetle, Autoserica castanea Arrow. Earlier, when the seedlings were 4 to 6 inches Figure 5. Field of com in \A'estport, showing effect of a heavy infestation of the Asiatic garden beetle, Autoserica castanea Arrow. in height, many had turned a reddish color, wilted and died. An examina- tion showed that the roots had been eaten. The field had been used for pasture or hay prior to its use for corn. The land was plowed in the fall and seeded to sweet corn in the spring. The field was visited about July 10 for observation. As it had not rained for about 10 days, it was possible to see thousands of emergence holes through which the adult beetles had left the ground. Some adult beetles were collected from the soil about the roots of some of the weeds (pussley) in the field. The field was about five acres in size and more than half of the first planting had been destroyed by the grubs earlier in the season. The injury was spotty and irregular with many areas devoid of corn. 314 Connecticut Experiment Station Bulletin 434 On October 23, 1939, 24 diggings one square foot in area and 15 inches in depth were made 100 feet apart in the field. Eight yielded no grubs, and the others yielded from 1 to 11 each. A total of 51 grubs, or an average of 2.1 to one square foot, was found. As the average number of grubs found per square foot was considered sufficient to injure the 1940 corn crop, it was recommended that the field be plowed and harrowed in the spring when the grubs are just below the surface of the ground. At the time the diggings were made, the grubs were from 6 to 8 inches deep. It was further suggested that the field be harrowed more than normally. [J. Peter Johnson] Results of Trapping Rose Chafers. A complaint was received that rose chafers, Macrodactylus subspinosus Fabr., were very numerous in a cemetery in New Haven, and considerable feeding was taking place. During the period while the adult beetles were present, from June 12 until early in July, 39 Japanese beetle traps were in operation in the in- fested portion of the cemetery. These were located throughout the area where the chafers were feeding, to points just beyond the infestation, cover- ing approximately five acres. The traps were not visited regularly but were emptied and checked at intervals throughout the period. When the last rose chafers disappeared, in early July, all the insects captured were measured. Four quarts of chafers had been caught and one quart of these was counted. It contained approximately 8,000 chafers, so the total catch for the season amounted to 32,000. Many chafers were not captured in the traps and there seemed to be no decrease in numbers throughout the season. Although traps will catch numbers of rose chafers they cannot be considered as a reliable method of control for this insect. [J. Peter Johnson] The European Earwig. Some notes by B. H. Walden on the occur- rence of the European earwig, Forficula auricularia Linn., in Connecticut were published in the 1938 report. During the past season a few observa- tions were made in an attempt to learn something about the degree and the extent of the infestation. Four standard earwig traps as developed by the U. S. Department of Agriculture were placed in the yard in Westville, where the earwigs were originally found, by a representative of the Bureau of Entomology and Plant Quarantine, Division of Forest Insect Investigations. One hundred thirteen of the insects were removed from these traps in one of the periodical checks made during the season. As the standard earwig traps were not available in quantity, 60 simple traps consisting of 4-inch flower pots filled with excelsior and inverted on stakes 14 inches long were placed on 20 properties in the neighborhood. Three were placed in each yard. The properties were selected on the basis of their location relative to the original infestation. Four sites were trapped in the city block containing the original infestation while two sites were trapped in each of the adjoining blocks, totahng nine blocks in all. Sixty-three earwigs were captured in these traps at six of the locations. Miscellaneous Insect Notes 315 The earwigs were originally found in a back yard on McKinley Avenue. The properties found infested in 1939 were primarily northwest of the 1938 site, toward Barnett Street and Fountain Street. This would indicate that the center of the colony was situated north or west of the place of original discovery. Further trapping in the future will in all probability settle this question. While making observations to determine whether or not the earwigs were feeding to any extent on flowers or foliage, 16 were taken from four dead dahlia blossoms. One neighbor reported that he captured three or four a day on his dahlias. No feeding of any importance was noted during the observations. [J. Peter Johnson] Bark Beetle Damage to Plantation Pine. In the fall of 1939 it was noticed that a number of pines in the experimental forest plantations of the Connecticut Agricultural Experiment Station at Rainbow were in a dead or dying condition (Figures 6 and 7). A survey was made to deter- mine the identity of the insects causing the injury, the extent of the dam- age, and the nature of the stands most heavily attacked. Three of the most extensively infested blocks were examined in detail. These consisted of a planting of pure white pine, one of pure red pine, and a mixed planting of the two. The msects found to be causing primary injury to the trees were bark beetles of the genus Ips, and included three species: Ips pini Say, /. grandicollis Eichh., and /. calligraphus Germ. Also present under the bark of red pine were numerous specimens of another bark beetle, Hypophloeus parallelus Melsh. The pure white pine stand was planted in 1902 and spaced 5 by 5 feet. Originally it covered 0.6 of an acre, but most of the stand was destroyed by the hurricane of 1938, and only 179 trees remain. The average diameter is 5 inches and the height is about 40 feet. Of these, five have been killed, while five others are infested and undoubtedly will die. The trees attacked are thus 5.6 percent of the total. In this stand bark beetle damage may be secondEo-y, however, as the trees were drastically exposed and rendered liable to sunscorch and other adverse cHmatic forces. In addition, some were injured by falling adjacent trees. The pure red pine stand was planted in 1917, spaced 5 by 5 feet, and includes 0.8 of an acre. The height of these trees is about 27 feet and the average diameter is 4 inches. Of the total of 750 trees, the number attacked by bark beetles is 33, or 4.4 percent. Of these, six are dead and five are dying. The red and white pines in the mixed stand were planted alternately, 5 by 5 feet apart, in rows 10 feet apart. The white pine has an average diameter of 4.5 inches and a height of 26 feet. The number of trees attacked is 10, or 1.2 percent, and of these three are dead and two are dying. Al- though the red pines have a thriftier appearance, the number of injured trees is much larger. The height averages 27 feet and the diameter 5.5 inches. In all, 66 trees are infested, or 8.0 percent of the total, and six of these are dead and nine are dying. The dead red pines in this stand have deteriorated rapidly ; the bark has fallen from the trunks and the branches, and wind storms have caused many of the infested branches to break off 316 Connecticut Experiment Station Bulletin 434 Figure 6. Base of white pine tree killed by Ips bark beetles, showing pitch tubes on trunk and boring dust on ground around trunk. Miscellaneous Insect Notes 317 (Figure 7). Both Ips pini and /. grandicollis were found in the branches. All three species previously listed were also found hibernating in the organic layer beneath the trees. Figure 7. Red pine tree about 27 feet high killed by Ips bark beetles. It has been reported recently that bark beetles have attacked red pine plantations in the Pachaug State Forest in southeastern Connecticut. Specimens taken from these trees have been determined as Ips pini. However, many of the trees were also infested by a weevil, Pissodes approxi- matus Hopk. Furthermore, one of the plantings was injured by a fire which occurred in the spring of 1939. [G. H. Plumb and A. DeCaprio] Clover Mite in Dwellings. Each summer we receive complaints about clover mites {Bryobia praetiosa Koch) entering homes. These pests are of no great economic importance, but when they enter homes in large numbers they become a nuisance to the housewife. They are so small that they can easily gain entrance through screens and under doors and windows. 318 Connecticut Experiment Station Bulletin 434 Most of the recommended methods of control have failed when the mites are present in large numbers. At one house in Branford, where these pests have been troublesome for several summers, the householder applied tree tanglefoot under the lowest course of clapboards all around the house to prevent the mites from crawling up higher and getting in through the screens. This stopped the mites from entering until the tanglefoot had become hardened or bridged over by the bodies of mites. As long as the householder kept the tanglefoot fresh and sticky there was no trouble, but this meant almost daily attention. As most of the mites were on the south and west sides, the lawn on these sides was covered with a fine sulfur dust for about 15 feet from the house. Shortly after the sulfur dust application it rained for nearly two days, following which mites seemed to be as abundant as before. Another light coating of dust was applied on a warm sunny day. Several hot days followed immediately after the application. The householder reported about two weeks later that the mites were apparently all gone and there was no further trouble with this pest the rest of the summer. [M. P. Zappe] Calomycterus setarius Roelofs in Connecticut. This weevil, a na- tive of Japan, was first discovered in Connecticut in the town of Salisbury in 1932. Since then it has been found in the towns of Sharon, Stratford, Fairfield, Westport, and Greenwich. The largest infestation, in the town of Stratford, covers about one square mile. Adults have been rather abundant here and have been found feeding on Lespedeza, Desmodium and several species of clover. The larvae live in the ground and feed on roots of various plants. The adults are wingless and have the curious habit of crawling up the sides of houses and entering through doors and windows. They appear to prefer houses that are painted white. The Stratford infestation has apparently not increased in intensity. During the summer of 1939 the adults appeared to be less numerous than they were in 1938. Neither did their host plants show as much feeding injury in 1939 as during the previous year. It was feared that they might become abundant enough to cause economic injury to fields of clover, but this has not yet happened. [M. P. Zappe] PUBLICATIONS, 1939 W. E. Britton Connecticut State Entomologist. Thirty-Eighth Report. Bui. 428, 122 pp., 16 figs., with index. Aug., 1939. W. E. Britton and P. Garman Report of Committee on Injurious Insects. Proc. 48th Annual Meeting, Conn. Pomol. Soc, p. 76 (3 pp.). March, 1939. W. E. Britton and M. P. Zappe Inspection of Nurseries, 1938. Reprinted from Bui. 428, pp. 24-33, (10 pp.). R. B. Friend The Spruce Sawfly {Neodiprion polyiomum Htg.) and the European Pine Shoot Moth {Rhyacionia huoliana SchifF.). Proc. Eastern Shade Tree Conf., p. 50 (4 pp.). Dec, 1938. The Dutch Elm Disease Situation in Connecticut. Eastern Plant Board, Baltimore, Md., Nov. 16, 1938. Mimeog. Publ. Feb., 1939. Publications 319 Philip Garman EfTectiveness of Parasites for Controlling the Oriental Fruit Moth. Mass. Fruit Growers Assn., Inc., Rept. of 45th Annual Meeting, p. 70 (5 pp.). Jan., 1939. Control of the Rosy Apple Aphid in Connecticut Apple Orchards. Circ. 126, 16 pp., 12 figs. Dec, 1938. The European Red Mite and Its Control. Bui. 418, 34 pp., 6 figs. Nov., 1938. Important Insects of the Apple Orchard and Methods of Control. Proc. 58th Annual Meeting, Conn. Pomol. Soc, p. 81 (7 pp.). March, 1939. Fruit Insect Problems in Connecticut. The Rural New Yorker, p. 546 (2 pp.). Oct., 21, 1939. Neely Turner Construction of Metal Termite Shields. Pests, Vol. 7, p. 16 (2 pp.). Feb., 1939. Control of European Corn Borer by Sprays and Dusts. Circ. 130, 4 pp., 1 fig. Feb., 1939. Control of European Corn Borers on Dahlias. Circ.133, 3 pp., 1 fig. May, 1939. Neely Turner and J. F. Townsend Control of Termites in Buildings. Circ. 134, 14 pp., 8 figs. May, 1939. J. P. Johnson Control of the Japanese Beetle. Circ. 132, 14 pp., 7 figs. May, 1939. R. C. BOTSFORD Progress of Mosquito Control in Connecticut. Proc. 26th Annual Meeting, N. J. Mosq. Exterm. Assoc, p. 127 (6 pp.). March, 1939. B. J. Kaston A Note on Synonymy in Spiders (Araneae: Salticidae and Argiopidae). Ent. News, Vol. xlix, p. 258 (2 pp.). Nov., 1938. North American Spiders of the Genus Agroeca. Reprinted from the American Midland Naturalist, Vol. 20, No. 3, p. 562 (9 pp.). Nov., 1938. Notes on a New Variety of Black Widow Spider from Southern Florida. The Florida Ent., Vol. xxi. No. 4, p. 60 (2 pp.). Dec, 1938. The Native Elm Bark Beetle, Hylurgopinus rufipes (Eichh.), in Connecticut. Bui. 420, 39 pp., 19 figs. Feb., 1939. A. W. Morrill, Jr., and D. S. Lacroix Report on the Insect Investigations for the 1938 Season. In Report of Tobacco Substation at Windsor for 1938. Bui. 422, p. 42 (8 pp., 6 figs.). March, 1939. G. W. Barber, Associate Entomologist, Bureau of Entomology and Plant Quarantine, U.S.D.A. Hibernation of the Corn Eau- Worm in Southern Connecticut. Bui. 419, 27 pp. Jan., 1939. 320 Connecticut Experiment Station Bulletin 434 SUMMARY OF OFFICE AND INSPECTION WORK Insects received for identification 568 Nurseries inspected 420 Regular nursery certificates granted (399 nurseries) 409 Duplicate nursery certificates for filing in other states 135 Miscellaneous certificates and special permits granted 190 Nursery dealers' permits issued 97 Shippers' permits issued to nurserymen in other states 173 Blister rust control area permits issued 195 Certification and inspection of occasional shipments Parcels of nursery stock 1,696 Corn borer certificates 1,204 Packages of shelled corn and other seeds 2,535 Japanese beetle certificates Nursery and floral stock and farm products 41,574 Orchards, gardens, fields and lawns examined^ 240 Buildings examined for termites, etc 62 Shipments of imported nursery stock inspected 13 Number of cases 37 Number of plants 276,400 Apiaries inspected 1,627 Colonies inspected 8,936 Apiaries infected with American foul brood 83 Colonies infected with American foul brood 147 Towns covered by gypsy moth scouts 75 Infestations discovered 430 Egg-clusters creosoted 8,260,640 Larvae and pupae killed by hand 53,151 Infestations sprayed 31 Lead arsenate used (pounds) 150,496 Miles of roadside scouted 1,200 Acres of woodland scouted 204,350 Letters written^ 4,080 Circular letters issued 1,356 Bulletins and circulars mailed 6,067 Packages sent by mail and express 42 Post cards mailed '. 505 Lectures, papers and addresses at meetings 41 ' Including 46 calls on vegetcible survey. 2 Including 148 letters written from the gypsy moth office at Danielson. INDEX Adelges ahietis, 227 cooleyi, 227 Altica ulmi, 223, 225 Aluminum acetate, 269, 270 sDicate, 265 sulfate, 270 American foul brood, 237, 238 Ammonium nitrate, 273 Anasa tristis, 222, 285, 286 Anomala orientalis, 218, 224, 225 Anuraphis roseus, 224 Apple and thorn skeletonizer, 218 maggot, 222, 224, 264-269 sprays, tests of, 260-264 Armyworm, 224 Asiatic beetle, 218 garden beetle, 225, 313 Autoserica castanea, 225, 313 Barium fluosilicate, 278-282 Bark mites, 307 Bassus diversus, 258, 259 Bentonite, 269 Birch leaf-mining sawfly, 218 Black carpet beetles, 225 dye, 266 Blissus hirtus, 222, 224 Bordeaux mixture, 275, 277-282 Bran, 312, 313 Britton, Wilton Everett, 215-221 Brown-taU moth, 242 Bryohia praetiosa, 317 Cabbage maggot, 224 Calcium arsenate, 278-282 Calomyderus setarius, 318 Carpenter ant, 225 Cedar rust, 262, 264 Cerodontha femoralis, 216 Chalepus dorsalis, 223 Cheiropachys colon, 307 Chinch bug, 222, 224 Chinese praying mantid, 225 Cicada killer, 225 Cirphis unipuncta, 224 Clay, 266, 278 Clover mite, 317 Codling moth, 261-264 Colorado potato beetle, 216, 275 Conotrachelus nenuphar, 223, 225 Copper, 280 sulfate, 262, 263 Corn ear worm, 224 Crazy ant, 311, 312 Creosote, 239, 308, 310 oil, coal-tar, 308 Crown gall, 236 Cube, 278 CurcuMo, 261-264, 272 Cydocephala borealis, 222 Daiana integerrima, 223 Deer, 257, 258 Dermestes sp., 312 Derris, 250, 264, 285 Diahrotica vittata, 224, 285, 286 Diodes molestae, 258, 259 Diprion simile, 218 Dry lime-sulfur, 260-263 Dual-fixed nicotine dust, 273, 275, 286, 287 Dutch ehu disease, 219, 293, 299, 305, 308 "Dynamite" sticker, 269-272 Eastern cottontail, 257 Elm bark beetles, 219, 306 flea beetle, 223, 225 leaf beetle, 216 spanworm, 223 Emphytus cindus, 236 Empoascafabae, 224 Ennomos subsignarius, 223 Enoderus nigripes, 307 Epilachna varivestris, 219, 224 Epiirix cucumeris, 222, 224, 277-283 European corn borer, 218, 222, 224, 226, 273-276, 281, 286 earwig, 224, 314, 315 elm bark beetle, 222, 223, 293-311 foul brood, 218 hare, 257 pine shoot moth, 222, 227 red mite, 218, 222, 224, 260, 268 spruce sawfly, 219 Fall webworm, 223 Felted beech scale, 219 Fish oil, 239, 250, 260. 262, 263, 270, 278- 282. 286. 287 Fleas, 225 Flotation sulfur, 260-262 Forest tent caterpillar, 223 Forficula auricularia, 224, 314, 315 Fruit speck. 260, 262, 263 Fuel oil, 251 Gallo-tannin, 275 Genicide, 264 German roach, 225 Glue, 263 Grapholitha molesia, 218, 222, 223 Greenhouse whitefly, 216 Gryllus domeslicus, 312, 313 Gypsy moth, 218, 222, 223, 226 control, 239-247 Harlequin cabbage bug, 224 Heliothis obsoleta, 224 Hickory beetle, 305 tussock caterpillar, 225 House cricket, 312, 313 Hylemyia brassicae, 224 Hylurgopinus rufipes, 296, 301, 304, 306, 309 Hyphanlria cunea, 223 Hypophloeiis parallelus, 315 Indian meal moth, 225 Inspection of apiaries, 237-239 imported nursery stock, 236 nurseries, 227-236 Ips calligraphus, 305, 315 grandicollis, 305, 315, 317 oregoni, 307 pini, 305, 315, 317 322 Connecticut Experiment Station Bulletin 434 Japanese beetle, 219, 222, 223, 226, 248- 250 parasites, 259-260 Lampblack, 266 Lead arsenate, 239, 241, 242, 250, 260, 262, 263, 268, 270-273, 278-282, 285-287, 308 Leafhoppers, 279, 280, 282 Lepus europaeus hybridus, 257 Lime, 260, 262, 263, 270-272, 277-282 hydrated, 262, 278, 280, 282 sulfur, 268,272, 273 Limonius agonus, 224 Linseed oil, 270 Locust leaf miner, 223 Macrocentrus ancylivorus, 258 Macrodadylus subspinosus, 224, 225, 314 Macrosiphum solanifolii, 224 Magdalis sp., 304 Magnetic sulfur, 260-262 Malacosoma disstria, 223 Manganese sulfate, 272, 273 Marmota monax, 255, 257 Meadow mouse, 254, 255, 257 Melitiia satyr iniformis, 224, 285, 286 Mexican bean beetle, 219, 224 Mice, 254, 255, 257 Microlus pennsylvanicus, 254, 255, 257 Milky disease, 250 Molasses, 312 Mosquito control, 251-254 Murgantia histrionica, 224 New England cottontail, 257 Nicotine, 260, 273 sulfate, 285, 286 Oak twig girdler, 297 Odocoileus virginianus, 257, 258 Odontocera dorsalis, 216 Oleic acid, 286 Oncideres cingulatus, 297 Orgilus longiceps, 259 Oriental beetle, 224, 225 fruit moth, 218, 222, 223 parasites, 258-259 Oyster-shell scale, 227 Parasitylenchus scolyti, 307 Paratetranychus pilosus, 218, 222, 224, 260, 268 Paratrechina longicornis, 311 Paris green, 312 Pegomyia hyoscyami, 224 Perilla oil, 270-272 Phytomyza aquilegiae, 21 6 Pine blister rust, 227 leaf scale, 227 mouse, 255 Pissodes approximatus, 317 Pitymys pinetorum, 255 Plum curcuho, 223, 225 Popillia japonica, 219, 222, 223, 226, 248- 250 Poplar- canker, 227 Porlhetria dispar, 218, 222, 223, 226, 239- 247 Potato flea beetle, 222, 224 control, 277-283 leafhopper, 224 Powdery mildew, 285, 286 Pyrausta nubilalis, 218, 222, 224, 226, 273- 276, 281, 286 Pyrethrum, 285 Pyrophyllite, 264, 265, 268, 269 Quebracho-fixed nicotine, 264 Quebracho tannin, 275 Rabbits, 257 Red-banded leaf roller, 222, 272 Rhagolelis pomonella, 222, 224, 264-269 Road dust, 277 Rodents, 222 control, 254-258 Rose chafer, 224, 225, 314 Rosin residue, 250 Rosy apple aphid, 224 Rotenone, 250, 264-269, 278, 281, 282, 285 Sacbrood, 237, 238 Salt marsh mosquito, 218 Salt water spray, effect, 287-293 San Jose scale, 216-218, 227 Scab, 260-264 Scolytus muUistriatus, 222, 223, 293-311 quadrispinosus, 305 Smaller European elm bark beetle, 293-311 Sooty blotch, 260-263 Soybean flour, 272, 273 oU, 270 Spathius canadensis, 306 Spinach leaf miner, 224 Spruce gaU aphid s, 227 Squash bug, 222, 285, 286 vme borer, 224, 285, 286 Striped cucumber beetle, 224, 285, 286 Sulfur, 260-263, 268, 270, 272, 273, 318 Sylvilagus floridanus mallurus, 257 transitionalis, 257 Termites, 222, 225 Tetramethyl tliiuram disulfide, 250 Tiphia popilliavora, 260 vernalis, 250, 259, 260 Tree tanglefoot, 318 Trichogramma, 223, 258 Triethanolamine, 286 Walnut caterpUlar, 223 Western dynamite spray, 286, 287 Wettable sulfur, 270 Wheat flour, 250 White arsenic, 312 lubricating oil, 265 pine weevil, 222, 227 -tail deer, 258 Wilt disease, 285 Wireworms, 224, 283-284 "g^oodchucks, 255,/25'p "X" disease, 227 '"*" '^ Xyleborus sp., 305 Zinc phosphide, 254 stearate, 266 M U'c University of Connecticut Libraries 39153029045343