Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF ENTOMOLOGY— BULLETIN No. 66. L. O. HOWARD, Entomologist and Chief of Bureau. SOME INSECTS INJURIOUS TO TRUCK CROPS. I. THE ASPARAGUS MINER. NOTES ON THE ASPARAGUS BEETLE^ By F. H. CH TTENDEN, Entomologist in Charge of Breeding Experiments. 1 T II. THE WATER-CRESS SOWBUG. THE WATER-CRESS LEAF-Bfem By F. II. CHITTENDEN, Entomologist in Charge of Breeding Experiments. III. THE CRANBERRY SPANWORM. THE STRIPED GARDEN CATERPILLAR. By F. II. CHITTENDEN, Entomologist in Charge of Breeding Experiments. ) LEAFHOPPERS OF THE SUGAR BEET AND THEIR RELATION TO THE "CURLY-LEAF" CONDITION. By E. D. BALL, Ph. D., Special Field Agent. % V. THE SEMITROPICAL ARMY WORM. By F. H.CHITTENDEN and H. M. RUSSELL. VI. THE HOP FLEA-BEETLE. By F II. CHITTENDEN, Se. D., in Charge of Truck Crop and Special Insect Investigations. VII. MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS By F. 11 CHITTENDEN, Sc. D., in Charge of Truck Crop and Stored Product Insect Investigations. WASHINGTON: GOVERNMENT PRINTING OFFICE. 19 10. U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF ENTOMOLOGY— BULLETIN No. 66. L. O. HOWARD, Entomologist and Chief of Bureau. SOME INSECTS INJURIOUS TO TRUCK CROPS. I. THE ASPARAGUS MINER. NOTES ON THE ASPARAGUS BEETLES. By F. H. CHITTENDEN, Entomologist in Charge of Breeding Experiments. II. THE WATER-CRESS SOWBUG. THE WATER-CRESS LEAF-BEETLE. By F. H. CHITTENDEN. Entomologist in Charge of Breeding Experiments. III. THE CRANBERRY SPANWORM. THE STRIPED GARDEN CATERPILLAR. By F. H. CHITTENDEN, Entomologist in Charge of Breeding Experiments. IV. THE LEAFHOPPERS OF THE SUGAR BEET AND THEIR RELATION TO THE "CURLY-LEAF" CONDITION. By E. D. BALL, Ph. D., Special Field Agent. V. THE SEMITROPICAL ARMY WORM. By F. H. CHITTENDEN and H. M. RUSSELL. VI. THE HOP FLEA-BEETLE. By F. H. CHITTENDEN, Sc. D.. in Charge of Truck Crop and Special Insect Investigations. VII. MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. By F. H. CHITTENDEN, Sc. D., in Charge of Truck Crop and Stored Product Insect Investigations WASHINGTON: GOVERNMENT PRINTING OFFICE, 1910. B UREA U OF EN TO MO LOG Y. L. 0. Howard, Entomologist and Chief of Bureau. C. L. Marlatt, Assistant Entomologist and Acting Chief in Absence of Chief. R. S. Clifton, Executive Assistant. Chas. J. Gilliss, Chief Clerk. F. H. Chittenden, in charge of truck crop and stored product insect investigations. A. D. Hopkins, in charge of forest insect investigations. W. D. Hunter, in charge of southern field crop insect investigations. F. M. Webster, in charge of cereal and forage insect investigations. A. L. Quaintance, in charge of deciduous fruit insect investigations. E. F. Phillips, in charge of bee culture. D. M. Rogers, in charge of preventing spread of moths, field work. Rolla P. Currie, in charge of editorial work. Mabel Colcord, librarian. Truck-Crop and Stored Product Insect Investigations. F. H. Chittenden, in charge. H. M. Russell, C. H. Popenoe, D. K. McMillan, H. O. Marsh, E. G. Smyth, Thos. H. Jones, agents and experts. E. D. Ball ,« special field agent. E. G. Titus, a I. J. Condit, H. S. Heller, & W. B. Parker, collaborators. a Resigned June 30, 1909. * Resigned January 31, 1910. u I I \ I LETTER OE TRANSMITTAL. U. S. Department of Agriculture, Bureau of Entomology, ItVasMngton, D. C, January 25, 1910. Sir: I have the honor to transmit herewith, for publication as Bulletin Xo. 66, seven papers dealing with certain insects injurious to truck crops. These papers, which were issued separately during the years 1907 and 1909, are as follows: The Asparagus Miner and Notes on the Asparagus Beetles, by F. H. Chittenden; The Water- Cress Sowbug and the Water-Cress Leaf-Beetle, by F. H. Chittenden: The Cranberry Spanworm and the Striped Garden Caterpillar, by F. H. Chittenden; The Leafhoppers of the Sugar Beet and Their Relation to the "Curly-Leaf" Condition, by E. D. Ball; The Semi- tropical Army Worm, by F. H. Chittenden and H. M. Russell: The Hop Flea-Beetle, by F. H. Chittenden; Miscellaneous Notes on Truck-Crop Insects, by F. H. Chittenden. Respectfully, L. O. Howard, Entom ologist a nd Oh iff of Burea u . Hon. James Wilson, Secretary of Agriculture. in PREFACE The present publication comprises a series of articles which have been issued in seven parts and are now brought together as a siiiLfl*- bulletin. It relates to a line of investigations begun in 1896, the earlier results of which were published in previous bulletins of the present series, in Yearbooks of the Department, and in circulars of the Bureau. The title, "Some Insects Injurious to Truck Crops," is used in a wide sense and includes insects injurious to sugar beet, since the same class of insects which affect this important crop also attack table beets and spinach. The initial article is the first treatment that has been given to the asparagus miner in a Government publication. The second article, entitled " Notes on the asparagus beetles," is a sequel to a general article on the asparagus beetles which appeared in the Yearbook for 1896. It places on record all important new localities to date, and furnishes similarly the latest information in regard to remedies. The importance which has been assumed by the water-cress sowbug since 1902 has necessitated the preparation of a publication covering this species, with suggestions for its control. The subject of water-cress insects has never been considered in a Department publication hith- erto, and similar treatment of the water-cress leaf-beetle to that furnished on the sowbug follows. The cranberry spanworm is given monographic treatment not hitherto furnished for it. It is an omniv- orous feeder, and has attracted attention on various crops, and especially on asparagus and strawberry. A similar article on the striped garden caterpillar, also an omnivorous form, completes Part III of the bulletin. The article representing Part IV is a detailed consideration of the sugar-beet leafhopper and of other affiliated species in their relation to the "curly-leaf" condition of the sugar beet. It was prepared by Dr. E. D. Ball while special field agent of this Bureau in Utah : he has been engaged on this work for a number of years. The semi- tropical army worm is the subject of Part V. It was the most trouble- some insect on truck crops in Florida during 1007, and was given detailed study from every possible standpoint by the authors. In the experiments with remedies, which were conducted by the junior author, Mr. II. M. Russell, a series of 15 trials was performed, proving that a spray of arsenate of lead is far superior to Paris green under local VI SOME INSECTS INJURIOUS TO TRUCK CROPS. conditions. The final article of the series, entitled "The hop flea- beetle," has been a subject of study for a number of years. Its treatment is monographic to date, and, while some of the data fur- nished are preliminary in character, it will constitute a basis for future work on the same species. This insect is given the name of flea-beetle because of the local name,- "hop flea," used in the hop- growing region of the Pacific coast, but it is also a pest in sugar-beet fields and in urious to rhubarb, radishes, and other truck crops. In the preparation of the article the writer has been fortunate in obtain- ing the cooperation of various experts, including, particularly, Messrs. H. J. Quayle and Theodor Eder. Following this article are a few miscellaneous notes on truck-crop insects, the first two giving additional information in regard to the principal asparagus pests treated in Part I, the last furnishing addi- tional observations on the water-cress insects treated in Part II, with notes on the first injurious occurrence of the destructive pea moth and of a western root-maggot in the United States. F. H. Chittenden. CONTEXTS." Page. The asparagus miner (Agromyza rimpU x L< >ew I F. II. Ck ittenden . . 1 Descriptive 1 Distribution 2 Historical and biological notes 2 Recent injury 3 Remedial measures 4 Notee on the asparagus beetles F. II. Ckittendt n.. 6 The common asparagus beetle ( f'rioceris asparagi L.) 6 The twelve-spotted asparagus beetle {CriocerU 1 t- punctata L.> 9 The water-cress sowbug < Mancasellns brachyurus Hargerj F. H. CkitU ndt n.. 11 Descriptive 11 Reports of injurious occurrence 12 Methods of control 12 The water-cress leaf-beetle (Phsedon aeruginosa Suffr.) F. H. Ckitterub . . 16 Injurious occurrence 16 Descriptive 16 Literature 18 Habits of this and a related species 18 Methods of control 19 The cranberry spanworm (Chora pampinaria Guen.) F. H. Chittenden. . 21 Descriptive 21 Distribution 23 Biologic literature 24 Unpublished office notes 25 List of food plants 25 The insect's life history 26 Natural enemies 2'i Remedies 26 Bibliography 27 The striped garden caterpillar (Mamestra legitima Grote) F. H. Ckittendt . Descriptive 28 Biologic notes 29 Natural enemies 31 Summary of habits 32 Methods of control 32 The leafhoppers of the sugar beet and their relation to the "curly-leaf" condi- tion E. D. Ball.. 33 Introduction 33 The beet leafhopper ( Enu ttix tenella Baker) 35 Descriptive 35 Food plants Distribution 36 Life-history studies Economic relations 41 Economic summary and proposed remedies 47 Bibliographical references "The seven papers constituting this bulletin were issued in separate form on March 16. April 23, and August 31, L907, and on January 27, January 28, May S. and July 19, L909, respectively. VII VIII SOME INSECTS INJURIOUS TO TRUCK CROPS. The leafhoppers of the sugar beet and their relation to the "curly-leaf" con- dition— Continued. Page. Other leafhoppers 49 Eutettix strobi Fitch 49 Eutettix scitula Ball 49 Eutettix seminuda Say 50 Eutettix clarivida Van Duzee 50 Eutettix insana Ball, E. albida Ball, and E. pauperculata Ball 50 Eutettix striata Ball 50 Agallia sanguinolenta Prov 51 Agallia cinerea Osborn and Ball 51 Agallia bigelovix Baker 51 Agallia quadri punctata Prov. and A. novella Say 51 Empoasca sp 51 Conclusions in regard to ' ' curly-leaf " 52 The semitropical army worm (Prodenia eridania Cram.). F. H. Chittenden and H. M. Russell. . 53 Introduction 53 Descriptive 54 Origin and distribution 57 Literature and history 57 ' Recent injuries and biologic notes 58 Early records 62 Life-cycle periods and generations 62 Natural enemies 63 Methods of control 65 Resume of experiments and conclusions 68 Summary 69 Bibliographical list 70 The hop flea-beetle (Psylliodes punctulata Melsh.) F. H. Chittenden. . 71 Introductory 71 Descriptive 72 Distribution 73 Recent injuries 73 Methods of attack, food habits, and generations 76 Life history and habits 79 Notes on other species 81 Local conditions and natural influences 82 Methods of control 83 Arsenicals 83 Contact sprays 85 Bordeaux mixture 87 Mechanical and cultural methods 87 Literature 91 Bibliography 91 Summary 92 Miscellaneous notes on truck crop insects F. II Chittenden. . 93 Successful use of arsenate of lead against the asparagus beetle 93 A note on the asparagus miner 94 Injurious occurrence of the pea moth in the United States 95 A new western root-maggot 95 Notes on water-cress insects 96 Index 99 ILLUSTRATIONS. PLATES. Page. Plate I. Leafhoppers (Eutettix spp.) and their work. Fig. 1. — Eutettix tenella: a, Adult: b, nymph; c, wing; d, e, genitalia; /, eggs (greatly enlarged); g, section of beet stem, showing fresh cgg^ in place; h, same, showing eggs ready to hatch; i, old egg scars on beet stems; j, small leaf of sugar beet, showing characteristic ; "curly- leaf" condition; /:, enlarged section of back of an extreme case of "curly-leaf," showing "warty*" condition of veins. Fig. 2. — Eu- tettix strobi: a, Work of nymphs on lamb's-quarters; b, work of nymphs on sugar beet. Fig. 3. — Eutettix scitula: Adult. Fig. 4. — Eutettix clarivida: a, Wing; 6, head and pronotum; c, d, genitalia. Fig. 5. — Eutettix nigridorsum: Work of nymphs on leaf of Helian- thus. Fig. 6. — Eutettix straminea: Work of nymphs on leaf of another Helianthus. Fig. 7. — Eutettix insaaa: Wing. Fig. 8. — Eu- tettix stricta: a, b, Genitalia 34 II. Work of Eutettix tenella on sugar beet. Fig. 1. — Three "curly-leaf" beets, the result of attack by Eutettix tenella, and one normal beet from the same field, showing difference in size. Figs. 2. 3. — "Curly-leaf beets as seen in the field. Fig. 4. — Normal beets from same field 44 III. Work of Eutettix tenella on sugar beet. Fig. 1. — A large beet becom- ing "curly.'' Fig. 2. — Back of a leaf affected by "curly-leaf."' showing "warty " condition and curled edges 44 IV. Work of Eutettix tenella on sugar beet. Fig. 1. — A field of beets de- stroyed by "curly-leaf." Figs. 2, 3. — Cages used in the life-his- tory experiments 46 V. Spraying apparatus used in hopyards in British Columbia VI. View of hopyard, showing sheep keeping down weeds 88 VII. Method of capturing hop flea-beetles on tarred horse-sledges 90 TEXT FIGURES. Fig. 1. The asparagus miner (Agromyza simplex) : Fly 1 2. The asparagus miner: Larva, pupa, work 2 3. The water-cress sowbug ( Mancasellus brachyurus) 12 1. Cross section of cress pond, showing arrangement for avoiding damage by water-cress sowbug 13 5. The water-cress leaf-beetle (Phsedon aeruginosa): Larva, pupa, adult 17 6. The cranberry *\K\n\\orm (Cleora pampinaria): Moth, larva, and pupa.. 7. The striped garden caterpillar (Mamestra legitima): Moth, larva, and pupa 29 8. The semitropical army worm i [Prodenia eridania): Moth, egg, egg-maae, larvae 54 X SOME INSECTS INJURIOUS TO TRUCK CROPS. . Page. Fig. 9. The semitropical army worm: Work of larvae on "careless weed" in potato field 59 10. The semitropical army worm: Field of late Irish potatoes, showing vines entirely stripped by larvae 60 11. The semitropical army worm: Larvae eating bark of "careless weed;" also nymph of spined soldier-bug (Podisus maculiventris), predaceous on larvae of Prodenia eridania 61 12. Hop flea-beetle (Psylliodes punctulata) : Larva and adult 72 13. View of hopyard, showing how flea-beetles keep down vines 76 14. Hop leaves, showing work of flea-beetle 77 15. Work of flea-beetle after vines are grown 78 16. Trained hop shoots stripped by flea-beetle 79 17. Breeding and control cage in place over a hill 80 18. A crew spraying hops in British Columbia 86 19. Tarred catchers for hop flea-beetles 89 U. S. D. A., B. E. Bui. 66, Part I. tamed March 16, 1907. SOME INSECTS INJURIOUS TO TRUCK CROPS. THE ASPARAGUS MINER. (Agromyza simplex Loew. I By F. II. Chittenden, Entomologist in Charge of Breeding Experiments. The stalks of asparagus are frequently attacked by insects, and in recent years have been reported considerably injured by the larva or maggot of a minute black fly to which the name asparagus miner has been given. The larva mines under the epidermis of the stalk, and when it has transformed to the puparium or "flaxseed" stage the thin outer skin becomes more or less ruptured and the presence of the insect is easil}T detected. It operates more abundantly near the base of the stalks and penetrates belowr the surface of the ground to a depth of 7 or 8 inches. During the year 1906 this species attracted considerable attention by its abundance in some of the principal asparagus-growing sections of New England and it bids fair to become a pest of considerable importance. It was first noticed on asparagus Fig. 1.— Agromyza simplex: Fly, dorsal view at left, lateral view at right. Highly magnified (original). in 1896, ten years earlier than the present writing, prior to which time nothing was known of its habits. It is a native species and evi- dently restricted to asparagus as a food plant. Until the year L906 it had not been recognized as doing injury to cutting beds, although attack had been observed in various sections. The mines of the larvae about and below the bases of the stalks are frequently so abundant that they have the effect of girdling, so that the injured stalks can be readily pulled from the ground. DESCRIPTIVE. The parent insect is a two- winged fly (tig. 1), metallic black, with large prominent head and eyes, and clear wings, the wing expanse being about one sixth o( an inch (1 nun.). l Fig. 2.—Agromyza simplex: a, larva, lateral view; b, thoracic spiracles; c, anal spiracles; d, puparium from side; e, same from above; /, section of asparagus stalk, showing injury and location of puparia on detached sec- tion; a-e, much enlarged; /, slightly reduced (original). 2 SOME INSECTS INJURIOUS TO TRUCK CROPS. The larva (fig. 2, a) is about one-fifth of an inch long and milk- white in color. Like other maggots, it is footless, large at the posterior extremity, and tapering toward the head. The puparium (fig. 2, d, e) is not unlike the "flaxseed" of the perni- cious Hessian fly, with which it has been aptly compared. At a little dis- tance, also, it suggests a Lecanium scale. This stage is remarkable be- cause of its peculiar flattened and curved position, as seen from the side. It is red in color, and meas- ures about 3.5 mm. in length and about 1 mm. in width. The egg has not been observed. This species belongs to the dipter- ous family Agromyzidae, and was described by Loew in 1869,a the locality being given as u Middle States." DISTRIBUTION. In its injurious occurrences this species appears to be limited to the eastern United States, from New England to Tennessee. From avail- able data it is quite obvious, however, that it may be destructive over a considerable territory, including a large portion of Massachusetts and Connecticut, Long Island, the District of Columbia, Pennsylvania, and Tennessee. As it is recorded from New Jersey, it is probably injurious there, although no reports of injury in that State have reached this office. In time it will doubtless attract attention in inter- mediate points and in States farther north and west. It has also appeared in asparagus beds in California. HISTORICAL AND BIOLOGICAL NOTES. In May, 1897, and afterwards this fly was observed in abundance by the writer on terminal shoots of asparagus, particularly at Cabin John, Md. Two weeks later no more flies were seen, but June 26 they reappeared and were then usually seen in copula. It was sur- mised at the time that this second appearance indicated the first new generation of the }^ear and its abundance on asparagus seemed to show that it lived in some manner at the expense of that plant. Examination of asparagus plants at that time, however, failed to show attack. The facts which have just been narrated were published in 1898. b "Diptera Americse septentrionalis indigena, Centuria octava 84, p. 46. &Bul. 10, n. s., Div. Ent., U. S. Dept. Agric, p. 62, 1898. THE ASPARAGUS MINER. 6 In 1900 we received complaint of injuries in the District of Columbia, and from Knoxville, Tenn., and in the meantime the species came under the observation of Mr. F. A. Sirrine, who has stated " that work was first observed in asparagus fields on Long Island in 1896. This statement is made in a bulletin of six pages, which represents all that was known of the species at that time. Late in September, 1900, word was received from Mr. Frederic Voigt, ^Tennallytown, D. C, of injury to the stalks of asparagus on his and a neighboring truck farm. When the writer visited the field, however, although injury was apparent on the outer skin of some stalks, no living specimens could be obtained, only the dried puparia being in evidence at this time. October 2 of the same year, Mr. Samuel M. Bain, University of Tennessee, Knoxville, Tenn., sent a stalk of asparagus showing the work of this miner upon the skin, and, October 27, specimens of the dried puparia. February 18, 1901, Mr. T. Miles Brous, Bustleton, Philadelphia, Pa., wrote that this insect, which he accurately described, seemed to cause much greater trouble than the common asparagus beetle. A neighbor had lost two or three new beds of asparagus on account of its ravages. By the writer's direction, Mr. F. C. Pratt visited a large truck farm at Brookland, D. C, where asparagus was one of the main crops, June 18, 1902. Asparagus was still being cut for market, but volunteer plants were growing here and there in fields of corn, cantaloupe, and potatoes, between rows. A few flies were seen on terminal shoots of asparagus that showed wilting, and many volunteer plants were found badly infested, most individuals having transformed to pupae. Although stems break off just below the ground, the entire colony of insects below that point is left with sufficient moisture and nourish- ment for their maintenance. The puparia were present in great numbers underneath the outer skin of the root, and as many as nine puparia were counted in a space only an inch long on one stalk. The stalks below the point of injury appeared to be perfectly sound. Larvae also were found in rotting stalks that broke off just below ground. During 1905 Mr. Ralph E. Smith reported this species as becoming abundant in California, though not of any great importance at that time. His description of the insects' manner of work leaves no doubt as to the identity of the species.6 RECENT INJURY. During September, 1906. Messrs. »I. B. Norton and A. IX Shamel, of the Bureau of Plant Industry, furnished stems of asparagus from Concord, Mass., showing severe infestation by this species, nianv « Bui. 189, N. Y. Agric. Exp. Sta., p. 277, Geneva, L900, 6 Bui. 165, Univ. of Oil. Agric. Exp, Sta., p. 96, L905, 4 SOME INSECTS INJURIOUS TO TRUCK CROPS. puparia being present under the mined outer skin. In the neighbor- hood of Concord, a very important asparagus-growing region where hundreds of acres are devoted to this crop, the infestation was practi- cally absolute, the insect being found even as abundantly as the common asparagus beetle, being present wherever rust was found, as also where no rust was present. The specimens submitted were about the average as regards the degree of infestation, some plants showing injury 7 inches below the surface. Severe injury was reported on the farms of Mr. Frank Wheeler and Mr. Charles W. Prescott, at Concord, Mass. The growers in that region had never noticed this insect until Mr. Shamel's examination showed that its injuries were extensive. Later Mr. Shame! reported finding infestation in every field and patch of asparagus which he visited in Massachusetts and Connecticut, particularly at Suffield, Granb}^, and Hartford, Conn., and he believed attack to be widespread. October 26, 1906, Mr. Ralph E. Smith wrote, by request, that the conditions under which this asparagus miner was found in abundance in the yellow stalks of asparagus in California, as reported by him in an article on Asparagus Rust Control,0 had prevailed for two or three years. The insect was al waj^s very abundant at the base of these yellow, dying stalks, although the injury was attributed to the "centipede," reported as wireworms on a previous occasion.6 REMEDIAL MEASURES. Witn our present knowledge of the life economy of this species, two methods of control suggest themselves as of greatest value, and it may be that the}7 will prove all that is necessary under ordinary conditions. (1) In spring permit a few volunteer asparagus plants to grow as a trap crop, to lure the fly from the main crop or the cutting beds for the deposition of her eggs. After this has been accomplished the trap crop should be destroyed b}T pulling the infested plants and burning them with their contained puparia. The time to pull the plants will, vary according to locality and somewhat according to season also. The second and third week in June would be about the right time in and near the District of Columbia. On Long Island this work should be done a week or two later. In the northernmost range of this insect — for example, in Massachusetts — the last of June and the first of July would probably be a suitable time. (2) The second generation can be destroyed in like manner by pull- ing old infested asparagus stalks as soon as attack becomes manifest and promptly burning them also. «Bul. 172, Univ. Cal. Agric. Exp. Sta., p. 21; &Bul. 165, 1. c. THE ASPARAGUS MINER. 5 If this work were carefully done over a considerable area, it would leave little necessity for other methods, since it would do away with these insects in the vicinity and leave few to be dealt with another season; unless, indeed, this insect has an alternate food plant. The cooperation of neighboring" asparagus growers and thoroughness are essential for success. This method will operate also against the rust which is now present in many fields infested by the miner. NOTES ON THE ASPARAGUS BEETLES. By F. H. Chittenden, Entomologist in Charge of Breeding Experiments. Since the publication of the writer's general article on the asparagus beetles in the Yearbook for 1896, a many notes on their distribution and destructive occurrences have been published. Some additional data were published soon afterward.6 The following- brief review of the subject is submitted as a sequel to those articles and a summary of the further dissemination of these pests in a decade of years. THE COMMON ASPARAGUS BEETLE. ( Crioceris asparagi L. ) The predictions made by the writer in regard to the future distri- bution of the common asparagus beetle have been completely fulfilled as regards its western spread, although it has not as yet been reported as far south as Kentucky. Mr. J. G. Sanders, however, informs the writer that it has been established about Columbus, Ohio, since 1903, and Mr. Charles Dury, Cincinnati, Ohio, reported this species at Indian Hill, about 7 miles from that city, on asparagus beds in 1905. Hundreds were observed during June. The customary injury was noticed, and plants appeared as though scorched with fire. In 1897 the species was observed to have continued its spread westward along Lake Erie, and was then known in nine counties in northeastern Ohio. The fol- lowing year it was first noticed in western Virginia. In 1898 also it was reported to have been present at Benton Harbor, Mich., since 1896. By 1899 it had made its appearance in Canada, accompanied b}^ the twelve-spotted species, in the Niagara River region. It is interesting to note that in 1900 the present species, which had been rapidly increasing its range in the East, including New York, after occurring in injurious numbers in Maryland, was apparently totally destroyed by the hot spell of July and August that occurred in the District of Columbia and neighboring parts of Virginia and Maryland; whence the conclusion that this condition prevailed to a considerably larger extent than came to the writer's personal notice. In 1901 Dr. James Fletcher noted that the species, though present in the Niagara district, had not increased to the extent that was feared. It had spread to Guelph, Ontario, that year, and did much damage about St. Catharines. In 1904 its occurrence around Toronto was a Yearbook U. S. Dept. Agric. f. 1896 (1897), pp. 341-352. 6 Bui. 10, n. s., Div. Ent., U. S. Dept. Agric, pp. 54-59, 1898. 6 NOTES ON THE ASPARAGUS BEETLES. 7 noticed. It was reported also 40 miles west of Chicago, 111. It has become very generally distributed in asparagus growing districts in New York State, and has reached Glens Falls, which approximates its northernmost limit in this country. In 1905 we received complaint of this insect as a pest in Illinois, at Park Ridge, and of its occurrence about Chicago. Reports from Michigan showed that it had been present there in 1904 in the vicinity of Ada, about 10 miles from Grand Rapids, and that it was a pest in that vicinity. Although the data given above indicate that the species is now well distributed throughout the Upper Austral region, for some reason its occurrence in Indiana has not yet come to our knowledge; neverthe- less although there are naturally many uninvaded localities, it is undoubtedly established in that State, most probably near Lake Michigan. As an example of its manner of distribution, it might be noted that in May, 1905, the beetle was found for the first time in Warrenton, Fauquier County, Va., a little farther inland than it had ever been noticed in that section. Yet this species has been permanently estab- lished in the adjoining Alexandria County for many years. August 8, 1905, Mr. Ralph E. Smith wrote of the occurrence of this species in California, stating that during two seasons it had been very abundant at Bouldin Island, the principal asparagus center of that region. As Mr. Smith was familiar with this insect and its occur- rence on the Atlantic coast, there is little doubt that his identification is correct. In the winter of 1904 to 1905 Bouldin Island was flooded and remained under water for over a 3 ear. It had just been reclaimed and there were no signs of the beetles. There is, therefore, a possibility that the insect was exterminated in that region, and this includes the State, if the occurrence of the species was only local. The dying out of this asparagus beetle in small localities where it has not become thoroughly established is not without precedent, as its recorded occurrence at Rock Island, 111., many }^ears ago, has been verified by specimens now in a Chicago museum, properly labeled as collected there by the late A. Bolter, an experienced collector of Coleoptera. Indeed, it would seem that few vegetable-feeding insects are more subject to extermination in a limited locality not contiguous to one also infested than is the present species. October 26, 1900, Mr. Ralph E. Smith, at the writer's request, reported the status of this species in California. He wrote that during the summer he found the beetles again, and that they were very abun- dant in fields near Oakley, Cal. It could not be stilted that the insect was of general occurrence in the State, but apparently it existed only in a few scattered colonies. As previously reported the colony at Bouldin Island appears to have been exterminated by flood, and 55908°— Bull. 66—10 2 8 SOME INSECTS INJURIOUS TO TRUCK CROPS. the Oakley occurrence was the first that Mr. Smith had noted since. In most of the asparagus acreage of the State the insect was not yet present. Mr. Franklin Sherman, jr., has kept a careful record of the occur- rence of this species in North Carolina, and informed the writer, on the occasion of a visit in 1906, that it is common in the east-central part of the State in the trucking belt, and especially abundant at Raleigh, Wake County, Goldsboro, Wayne County, and Warsaw, Duplin County. In order to make the present account of the known distribution of this species as complete as possible, inquiry was made of the official entomologists of the States of Kentucky, Iowa, Missouri, Nebraska, and Minnesota, all of whom reported that the occurrence of this spe- cies in their States had not been brought to their attention. Mr. James G. Moore, however, assistant in horticulture at the University of Wis- consin, Madison, Wis., stated that the asparagus beetle had been found in Wisconsin, but he had no special data on its distribution. REMEDIES. With regard to remedies good results have followed the experimental use of arsenate of lead. This insecticide has come into very general favor in recent years, and in the correspondence of this office we have for sometime advised its employment against most leaf -feeding beetles, like the asparagus beetles. In Connecticut Dr. W . E. Britton a has made a practical test of this remed}T on asparagus plants, spraying them from all four sides in succession because of the slight leaf exposure as com- pared with most other plants. The day following treatment (June 4) many dead beetles and larvae were found on and under the plants. A few had survived and were feeding, but ten days later only a few living larvse could be found, and the beetles did not again become abundant on the plants during the summer. The same amount of good might be accomplished with scarcely greater expense by spray- ing from opposite sides and repeating just before the time for the last generation to develop and in time to check the beetles before they go into winter quarters. In Pennsylvania Prof. H. A. Surface,6 in a series of experiments with Paris green and arsenate of lead, applied to asparagus plants the first week of June, 1905, found that not more than 50 per cent of the insects were killed when Paris green and lime were used. With lead arsenate 90 per cent were killed, while in one experiment, by the addi- tion of resin soap, which is used as an addition to an insecticide to a Kept. Conn. Agric. Exp. Sta. f. 1903 (1904), pp. 275, 276. & Monthly Bulletin, Div. of Zool., Pa. State Dept. Agric, Vol. IV, May, 1906, p. 8. NOTES ON THE ASPARAGUS BEETLKS. 9 enable the poison to adhere better to smooth plants, 100 per cent of the insects were killed on the 50 plants treated. In this case the arsenate of lead was used at the rate of about 1 pound to 24 gallons of water, and 2i pounds of soap were added. Arsenate of lead has been used with satisfactory results on asparagus at the rate of 1 pound in 16 to 21 gallons of water. Additional experi- ments are necessary to ascertain the exact amount of the poison that can be used economically to produce the best effect. In Professor Surface's experiments evidently only a single spray was applied. THE TWELVE-SPOTTED ASPARAGUS BEETLE. ( Crioceris 12-punctata L. ) Nearly every year since 1896, when the distribution of the twelve- spotted asparagus beetle was recorded by the writer," the appearance of this species has been noted in new localities in the United States, until it is now well distributed westward and especially northward. In 1898 Dr. J. B. Smith stated that it then occurred throughout the State of New Jersey "south of the shale from the Atlantic coast to the Delaware." The following year (1899) it was recorded by Dr. E. P. Felt from different counties in New York, and as far west as Buffalo. In some places the species was abundant, while in some near-by locali- ties it could not be found, showing that it was still locally distributed through New York. It was afterwards recorded present in Albany, Batavia, Leroy, Syracuse, Riverhead, Oswego, Center, Glendale, Richmond Hill, Penfield, Elmira, Geneva, Ithaca, and about Brooklyn, N. Y. It was also stated to occur in the Niagara district in Canada as far back as Hamilton, Ontario. An interesting point in regard to the occurrence of asparagus beetles in the Niagara peninsula was that the two species appeared to have arrived almost simultaneously in that region, but that the twelve- spotted form was by far the more common one. In after years dif- ferent observers noted its further spread in Canada, commenting upon the fact that it led the common species in becoming diffused by natural means. By 1902 it had appeared in Connecticut, at New Haven, and later in other parts of that State. Since some writers on these asparagus beetles have overlooked the author's second article6 it may be well to mention that facts additional to those printed in the writer's original article are given therein, including a description and illustration of the egg and its manner of deposition, and what is practically a complete account of the life his- tory of the species, the insect being found to develop and to feed where possible almost exclusively on the berry, although the beetles attack young asparagus shoots before the berries appear. " Yearbook U. S. Dept. Agrie. I L896 (1897), pp, 350-351. &Bul. 10, Div. Ent, U. S. Dept Agric, pp. 57 59, 1898. 10 SOME INSECTS INJURIOUS TO TRUCK CROPS. The young larva. — The freshly hatched larva has not hitherto been described. It may be briefly described as follows: Head rounded, nearly twice as wide as long as seen from above; thoracic plates distinctly separated at the middle, with the intervening space yellow; legsinfuscated, clear whitish at sutures. General color very pale yellowish, nearly white, and the surface much wrinkled. Length 1 mm. , width 0. 35 mm. U. S. D. A., B. E. Bui. 66, Part II. Issued April 23. 1907. SOME INSECTS INJURIOUS TO TRUCK CROPS. THE WATER-CRESS SOWBUG. (MancaseUus brachyurus Harder.) By F. H. ChIttendbn, Entomologist in Charge of Breeding Experiments. During the past three years this isopod has attracted very consid- erable attention because of its occurrence in troublesome number- in water cress (Nasturtium officinale) grown for market in portions of Virginia, West Virginia, and Pennsylvania. The species is purely aquatic, thus differing from our common dooryard sowbugs, which, although most abundant in moist locations, are strictly terrestrial. It belongs to an entirely different family, the Asellida?. which contains three genera, mostly fresh- water forms, inhabitants of streams, wells, pools, and lakes. DESCRIPTIVE. This species is so distinct from the more common sowbugs (Onis- cidse) that a brief description will suffice. Its general appearance is shown, dorsal view, in figure 3. The body is much depressed, and the legs are long and strong. Seen from the side, it is decidedly shrimplike. The peculiar structure of the antennae may be noticed in the illustration. They terminate in long flagella. composed of many joints. When mature this sowbug attains a length of 13 or 14 millimeters, or a little upward of half an inch, and is a little more than twice as long as wide, and gray in color. This creature is not an insect, but a crustacean, and therefore classed with crayfish and crab-. A detailed description is given by Miss Richardson,0 who briefly men- tions McKees Spring, Gaylord, and Lexington, Va.. as localities where this sowbug was " reported injurious to water cress." By recent correspondence we have obtained necessary information in regard to the habits and manner of operation of this sowbug. and we have also been successful in ascertaining what promises to be a very perfect reined}' for the pest in its occurrence in streams ami in spring water. It appears to a licet cress only below the surface of the water, attacking the roots and lower leaves, and cutting off the stems a Monograph of the [sopods of North America. By Harriet Richardson. Bui. 54. U. S. National Museum, Washington, L905, pp. 411-412, Bgs. 460-461. 11 12 SOME INSECTS INJURIOUS TO TRUCK CROPS. near the bottom, causing bunches of the plant to float. In portions of streams where these sowbugs have been found most abundantly they are frequently seen crawling in a thick mass at the bottom. They feed, so far as known, exclusively on cress, not being reported as attacking any other form of vegetation. REPORTS OF INJURIOUS OCCURRENCES. This sowbug has been observed as a pest since 1902. Our first report of its pernicious habits was made in 1901, when we received specimens through Mr. J. W. Bryan, Anacostia, D. C, from Hall- town, W. Va., where it was very injurious to water cress. In March, 1905, Mr. Powell Arnette reported injury at Gaylord, Va., to cress grown in spring water. The sowbugs were always found in the water and did not attack cress above the surface. After destro}dng the last vestige of cress in one of his ponds they remained on the bottom " a foot deep,'' crawling about on the mud. During 1906 (June 18) Mr. John H. Keed, Carlisle, Pa., wrote in regard to this species and its destructive work on water cress in his locality. Specimens were re- ceived August 11. The sowbug was ob- served principally on the roots and lower leaves, crawling up along the stem and cutting off the leaves. August 10 Mr. George C. Jordan, Washington, D. C., sent specimens from Basic City, Va., stating that this " water bug " was devouring his cress beds, and, since a million or more were colonized on the plants, there would be no crop at the rate they were reproducing. When the plants were lifted the sowbugs were observed to drop from them. Fig. 3. — The water-cress sowbug (Mancasellus brachyurus). En- larged (after Richardson) . METHODS OF CONTROL. Three ways of controlling this species are suggested. The first and most important consists in a method of growing the water cress so as to eliminate injuries by the sowbug. The second falls under the head of direct remedies, and none of these has as yet given sat- isfactory results. The third consists in the use of fish or fowls as destroyers. This last means of eradicating the pest has not yet had a fair trial. The following description of a successful method of disposing of the cress sowbug has been placed at our disposal by Messrs. B. Bryan THE WATER-CRESS SOWBUG. 13 & Son, who are practical cress growers and have had several years' experience with the pest : A METHOD OF GROWING WATER CRESS TO DISPOSE OF THE SOWBUG. The damage done by the sowbug to water cress has made it our greatest enemy in cress growing, and only after fighting it for four years have we suc- ceeded in finding a way to keep down its numbers so as to be sure of a crop. As cress is ordinarily grown — in lakes or streams of spring water anywhere from 6 inches to 3 feet in depth — it seems impracticable to apply any insecti- cide. At first we tried to catch the bugs with wire-netting traps placed where the whole stream of water had to pass through them, but the bugs remained among the cress, and we caught only about 20 per cent. Later, in using copper sulphate to kill moss in the cress, we found that it also killed the sowbngs, snails, etc., when applied freely. Further experiments, however, proved that bluestone could not be applied in deep running water any better than the insecticides previously tried, and when applied in shallow or still water it injured the cress. The method we are employing at present to fight the sowbug is largely a matter of arrangement of cress beds (see fig. 4), and can be used only where the bottoms of the beds can be graded and drained or where level land adjoins Fig. 4. — Cross section of cress pond showing arrangement for avoiding damage by the water-cress sowbug. the source of the water supply. We dug long trenches in level land, making them 1G feet wide and about 15 inches" deep. Lengthwise they were graded to give a fall of 3 inches in 100 feet, and crosswise to make the center of the trench several inches deeper than the sides. In the center and running the full length of the trench a trough made of three 10-inch boards was sunk below the bottom of the trench in such a way that all of the water might be drained out of the trench through it. Then, with the upper and lower ends of the trench and trough arranged to be opened or closed, the trench could be filled or emptied at will and the flow of water regulated up to 8 inches in depth over the cress. Of course fertile soil was put in the trenches aiid the cress could be planted either before or after the water was turned in. With cress beds arranged as above, manipulation to dispose of the sowbngs is simple. By cutting off the water supply and allowing the water to pass out at the lower end of the trench, the sowbngs will collect in the trough, following the receding water, as they can live only in water. No little puddles should remain among the cress, as the bugs will collect in them Instead ol' in the trough. It will be found necessary, also, to use boards to walk on in gathering the cress, as prints of one's boots in the beds would make holes for the hugs to shelter in. The bugs do not move until nearly all of the water is drawn out o( the trench. Thus they are collected in a small amount of water in the trough ami can then be readily killed with a liberal amount of bluestone, either solid or in solution. 14 SOME INSECTS INJURIOUS TO TRUCK CROPS. To make the work thorough, water should not be turned into the trench again for twelve or twenty-four hours, in which time the few bugs left among the cress stems will die or find their way to the trough. The trenches can be cleared of bugs in warm weather as frequently as desired, but less danger is done the cress crop if the work is done just after gathering the cress. The same method of disposing of the sowbugs could be used in greenhouses in the winter, but cress grown in the open air could not be exposed in freezing weather, making the remedy inapplicable in cold weather. We have not used water in these trenches deeper than 10 inches, and are not able to say how a larger or more rapidly flowing supply of water would act, nor have we grown winter cress in them, as our water supply is insufficient for that purpose. OTHER REMEDIES. About the only other remedies which we have been able to suggest are the use of a substance, such as sulphate of copper or chlorid of lime, which might be placed in the water to destroy the pest. As the former has already been tested by Messrs. B. Bryan & Son (see page 13), it need not be mentioned further. Mr. John H. Reed states that a grower at Healing Springs, Va., has a remedy consisting of a poisonous material which is placed in the water, but he does not know the ingredients nor whether there would be danger to stock drinking the water below the spring. He writes also of the possible use of chlorid of lime. A tank of bleach composed principally of chlorid of lime ran into a creek at Mount Holly Springs, Pa., killed everything that was living in that stream for about half a mile downward, but did not poison stock that drank the water. The bleach came from a paper-mill tank which had burst. If chlorid of lime is tested it should be used on a very small scale at first to note the effect on plant life. It is apt to be harmful to trout and other fish present. Mr. Reed also suggested the employment of ducks to destroy the pest, but this would necessitate the abandonment of cress culture for a season, as the ducks would injure the condiment both by eating it and by fouling the water. Among other remedies, we have recommended draining off the water where possible and exposing the sowbugs to the drying effects of the sun. FISHES AS A POSSIBLE MEANS OF DESTROYING THIS ISOPOD. In response to inquiry, the following information was received from the Bureau of Fisheries, through Mr. Lawrence O. Murray, Acting Secretary, Department of Commerce and Labor, in regard to the fishes which might be found useful in the destruction of this aquatic isopod in its occurrence on water cress : Among the fishes which would probably prove most useful for this purpose and with which it is suggested that the Department may wish to experiment THE WATER-CRESS SOWBUG. 15 are the fresh-water killifishes Fundulus nolo his. i\ diaphanus, and /■'. dispar. The first occurs from Michigan to Alabama, Mississippi, and Texas, and is rather common in small lowland ponds. The second is found from Maine to North Carolina in river mouths, in the Great Lakes, and in practically all of the small lakes in the upper Mississippi Valley. The third occurs in smaller lakes and ponds from northern Ohio to Illinois and south to Mississippi. Specimens of each of these species could be obtained at any one of several small lakes in the northern part of Indiana. It is probable that some of the catfishes might also be useful in this connec- tion, and it is suggested that it might be worth while to try one or more of the small species known as "mad Toms," belonging to the genus Schttbeodes. One or more species of this genus can be found in almost any small, sluggish stream in Pennsylvania, Virginia, and West Virginia. The writer believes that carp should prove of value in keeping down this cress sowbug, there being one drawback, however, that the carp must be watched to see that they do not develop too rapidly and that they do not attack the cress or make the water muddy. Cat- fish have been tried and found wanting in the case of the water-cress leaf-beetle, which will be considered elsewhere (pp. 1G-20). THE WATER-CRESS LEAF-BEETLE. (Phsedon aeruginosa Suffr.) By F. H. Chittenden, Entomologist in Charge of Breeding Experiments. INJURIOUS OCCURRENCE. Among plant-feeding native insects which have recently appeared in new roles is a little blackish leaf-beetle, Phcedon aeruginosa Suffr., which was reported for the first time as injurious to water cress (Nasturtium officinale) in Pennsylvania, in 1903. During September Mrs. Hannah B. Hannum, Brandywine Summit, Pa., sent larva? and adults of this species, with statement that they were devastating her water-cress pond. Both larva? and beetles fed chiefly on the lower side of the leaves. In confinement they con- tinued feeding, attacking the stalks also. The larvae all reached development about the same time, being fully matured September 11 and 12, on the last of these two days crawling about the rearing jar and ceasing to feed. The pupal period was not observed, but it probably lasted ten days or a fortnight, as the weather was cool. The beetles continued for some time in our rearing cages, frequently pairing, but depositing no eggs. August 19, 1904, Mrs. Hannum sent additional specimens of this species in the beetle and nearly grown larval stages. It was noticed that the beetles did not swim rapidly, but steadily, and they were seemingly not discomposed by being somewhat out of their natural element. It seems probable that they fly from plant to plant, and like most beetles undoubtedly are able to float for many hours, and perhaps even swim short distances until they reach a landing place. September 13 our correspondent sent still another lot of this species, mostly beetles, but a number of larvae were included. Specimens of the larvae of a syrphus fly accompanied this sending and probably fed at times on the small larvae of the beetle. DESCRIPTIVE. The oeetle. — This species belongs to the tribe Chrysomelini of the family Chrysomelidae. It is classified in our publications on the Coleoptera of America north of Mexico with Plagiodera, but Eu- ropean systematists place allied forms in the genus Phasdon Latr., which now comprises seven species occurring in our country. They are very small semiglobose forms. The outline is oval, with the thorax 16 THE WATER-CRESS LEAF-BEETLE. 17 narrowed anteriorly and the apex margined. The elytra have eight punctate striae, with a short subsutural and submarginal row of punctures. The third joint of the tarsi is emarginate apical ly. The present species measures a scant one-eighth of an inch in length (3 mm.), is shining bronzy black, and has the elytral intervals apparently smooth, but in reality faintly rugulose when highly mag- nified, while the thorax is microscopically reticulate. The original description appeared in 1858.a The egg. — The eggs have not come under observation. They prob- ably resemble those of the European Ph. armoraci(B L., described by Fryer as " elongated oval and of a dark orange color." Fig. 5. -The water-cress leaf-beetle (Phcedon ceruginosa) : a, adult; b, larva, from above; c, same, from side; d, pupa. Enlarged twelve times (original). The larva. — The larva appears somewhat like that of a related genus, Galerucella, only that it is very much smaller. It is about three or four times as long as wide, depending upon whether it is somewhat contracted or fully extended. The head is subtruncate in front, with the antennae lateral (in preserved specimens). The head is shining black, and the remainder of the body very dark brown or brownish black relieved by lighter areas between the segment-. The first thoracic segment is a little wider than the head: the ond considerably wider than that, and the third widest, being nearly as wide as the first two abdominal segments. The second abdominal is widest, and at the same time the widest part of the body. The surface is sparsely covered with long hairs placed on piliferous tu- bercles, which are arranged some distance apart, as shown in figure 5, b. The tubercles on the sides of the dorsum are sometime- very prominent, and the larva is able to extend these, possibly, at will. From the abdominal segments large tubercular sections bearing hairs at their summit extend on each side. The anal segment is pale, like the ventral surface, which bears dark piliferous tubercles. Length, 5 mm.; width, 1.2-1.5 mm. a Knt. Zeitung, Stettin, Vol. \i\. pp. 395, :»!»<;. L85& 18 SOME INSECTS INJURIOUS TO TRUCK CROPS. The pupa. — The pupa is illustrated by figure 5, d, which will answer better than a verbal description. The color is yellow, and the length is slightly less than that of the adult. The distribution of this species is probably moderately wide and additional study must be given this subject. At present we know of its occurrence in the District of Columbia, in Massachusetts, and probably in West Virginia. LITERATURE. Brief mention of the occurrence of this leaf-beetle as an enemy of water cress in Pennsylvania in 1903 was made by the writer,0 but Mr. Frederick Knab, of this office, mentioning the same species as Plagiodera viridis, has recorded h its occurrence in great abundance upon water cress near Springfield, Mass., in 1902. The identity of the species in question has been verified by the comparison of speci- mens, and Mr. Knab's record was evidently made on the assumption of Crotch c that aeruginosa was merely a variety of viridis. HABITS OF THIS AND A RELATED SPECIES. WTe can not at the present writing give an approximate statement of the life- history of Phcedon aeruginosa, and hence must depend on what is known of the related Ph. armoracice, which is common to both continents.^ This latter has evidently been introduced into this country, but its habits have apparently not been studied here. It is known in England as the blue beetle and mustard beetle/ and is of considerable importance locally, in some seasons ravaging entire fields of mustard, cress, cabbage, and kohlrabi. It passes the winter as adult, reappearing in spring on cruciferous plants. Fryer stated that in the three years prior to 1881 the Isle of Ely, England, suffered from the ravages of this species, entire fields being injured. Mustard was attacked at about the time of the formation of the seed pod and after the stalks were stripped nearly to the cuticle the beetles trans- ferred their attention to kohlrabi, which they completely consumed, at first attacking the leaves and afterwards the bulbs, leaving nothing but bare stalks. The water-cress leaf -beetle is doubtless no exception to the general rule among most Chrysomelidse and other species of Phsedon, in laying its eggs on the under side of the leaves. Both larvae and aYbk. U. S. Dept. Agric. f. 1903 (1904), p. 564; 6 Entomological News, March, 1903, p. 89 ; c Crotch, Proc. Acad. Phila., 1873, pp. 54, 55 ; * Phcedon armoraciw L. syn. : Plagiodera cochleariw Panz., Gyll. ; Phcedon oetulw Kust. It is not the same as cochleariw Fab. «Fryer and others have given accounts of this species in The Entomologist (Vol. XIV, pp. 44, 187, etc.). THE WATER-CRESS LEAF-BEETLE. 19 adults attack the cuticle of the stem after feeding on the leaves, as has been noticed in the case of armoracice. E. A. Fitch has ob- served the partiality of the latter for water cress and other crucif- ers which grow in watery places and mentions the destruction of an entire crop of horseradish. Kaltenbach a records, according to Gyllenhall and his own obser- vations', Veronica beccabunr/a, Cardamine amara, and Cochlearia armoracia or horseradish as food plants, and states that the larva undergoes metamorphosis in the earth, the pupa state lasting four- teen days. Cornelius b is cited as having observed two generations, the spring generation being found in May and June and the second in September. Thomas H. Hart records the water starwort of England (C allitricha verna) as another host plant. T. R. Billups,c an ento- mologist as well as truck grower, mentioning this species as Phcedon betida\ states that it is " one of the greatest insect pests the market o-ardeners around London have to contend with." Our American o species undoubtedly hibernate as adults and appear in early spring under boards and similar shelter. METHODS OF CONTROL. How to successfully control this insect under ordinary conditions is quite a problem. Paris green was tried by our correspondent, mixed with flour and sprinkled over the plants when the dew was on, and this reduced the numbers of the insect somewhat. Owing to the moist condition of the plants, however, the flour formed a paste which stuck like glue, and it was therefore abandoned. Applied in water it rolled off the plants. We were not informed if this appli- cation was made with a spraying machine. If the plants were sprayed lightly with a fine spray, it might answer, or, better, Paris green dry with only 20 parts of flour, or plaster or air-slaked lime. An arsenical should not be used within about a week of the time of cutting the cress for market. In the case of Paris green there is practically no danger of poisoning even if it were used later, as the washing which is given the cress will carry away all perceptible traces of the poison. If conditions should be such that the pond or stream in which water cress infested by this species is growing eon Id be completely overflowed, it would cause the insects to rise to the surface, and in the ease of running water would wash them downstream. Flooding alone might not entirely solve the problem, as these beetles are able to survive considerable immersion. When the cress is grown in sufficiently large bodies o( water e\- o Pflanzenf einde, p. 26; & Stett Ent Zeit, 1863, p, L23; °The Entomologist, Vol. XIV, 1881, p. 236. 20 SOME INSECTS INJURIOUS TO TEUCK CROPS. periments should be made with some of the fish mentioned on page 15 as possibly useful for destroying cress insects. Ducks might also be found valuable. Catfish were tried, but without avail. Mrs. Hannum has recently written that she attained the greatest success by growing the water cress in running water which carried the beetles away. In cold weather it was necessary to plant in houses where the cress did well until the coming of warm and dry weather, when the beetles would sometimes clean it out almost en- tirely, leaving only the roots. By tearing the cress out of the houses and in ponds which were not exposed to running water she could replant her beds, and hoped in time to get rid of the pest. U. 3. D. A.. B. E. Bui. 66, Part III. Issued August 31, 1907 SOME INSECTS INJURIOUS TO TRUCK CROPS. THE CRANBERRY SPANWORM. (Cleora pampinaria Guen.; By F. H. Chittenden, Entomologist in Charge of Breeding Experiments. A brownish spanworm has been observed by the writer during recent year- on asparagus in the District of Columbia in such numbers as to indicate that it is especially attached to this crop, at least in this region. In consideration of the fact that so few insects attack asparagus, the accompanying account has been prepared. The spe- cies appears to have attracted no attention since 1884,7 a when it was considered in relation to its ajopearance in cranberry 1 From material recently collected, several facts hitherto unrecorded have been gained, and there are a number of unpublished notes of the Bureau showing a tendency on the part of the species to become omnivorous. At any rate it is not confined to cranberry, as the name given above would imply, nor to strawberry, as might be in- ferred from another name, " brown strawberry spanworm."* which has also been given it. The list of food plants which will ] ently be furnished show- a considerable range. Owing to the fact that the insect has not often been observed concentrated on any -ingle crop, little mention of it has been made in literature by economic writers. Cranberry is a favorite food plant, and i> >ometimes in- jured to a considerable extent, especially in Massachusetts. DESCRIPTIVE. This insect belong> to the Lepidopterous family Geometridse, the larvae of which are well known under the commOD names of -pan- worm-, measuring-worms, inch-worms, and loopers. The moth which produces this spanworm is quite variable in color and marking-. The average expanse of wing i- from a little less than an inch to upward <.t' an inch and a fourth ). but may exceed this, attaining, according to Dr. A. S. Packard.1 a measurement of an inch and a half. The ground color of living specimens i< pale °Tho numbers in superior type refer t<> corresponding numbers in the appended bibliography, p. l'7. 21 22 SOME INSECTS INJUKIOUS TO TKUCK CROPS. leaden gray, and of old mounted material a duller gray, thickly dif- fused with black and brown dots and other markings more or less con- stant, forming irregular lines across both fore- wings and hind-wings. On both there is a marginal regular scalloped black line and within this a strongly dentate or zigzag white line. The general pattern of the wings varies considerably from that shown in figure 6, 2. Plate VIII, fig. h 1855 ( 1856). Probably this species. Appears in Carolinas, Georgia, and Florida early In October and feeds upon the petals of the cotton flower; larva and adult described and figured. 2. Gtjenee, M. A. Species General des Lepidopteres, Vol. IX. Phalenites, pp. 245, 246, iMs. 1857. Original description as Boarmia pampinaria from near Baltimore, as /,'. frugal- laria from Georgia, and as B. sublunaria from North America. 3. Landon, M. D. Kept Comm. Agr. f. 1864 I 1865), p. 90. Erroneously figured as the "cotton caterpillar (Xoctua sylina)." 4. Packard. A. S. Report U. S. Geological Survey Terr., Hayden, Vol. X, pp. 482. 442, Plato XI. fig. 20. 1876. Technical and detailed description of moth : synonymy ; distribution and note on larva and pupa, the former feeding on pear. 5. Glover. Townend. Cotton and its principal injurious insects. 60. 30 SOME INSECTS INJURIOUS TO TRUCK CROPS. tained, but it was about the 21st of October, which would give a period for the pupa of ten months, as the moths of this lot began issuing August 21.a One individual transformed to pupa October 17 and the imago issued August 24 of the following year. October 15, 1898, the larva was brought to the writer by Mr. P. H. Dorsett, from his greenhouse at Garrett Park, Md., where the species was feeding on the foliage of violet. The same year, Xovember 3, this larva was found rather abundantly by Doctor Howard in tobacco fields in southern Virginia, near the Xorth Carolina border line, upon the leaves, which in some cases were badly ragged.6 The first moths issued in July. During 1900 and 1901 correspondence was had in regard to this caterpillar with Mr. H. Walter Mc Williams, Griffin, Ga., who sent specimens, as also larva? of the so-called cotton cutworm (Prodenia ornithogalli Guen.), with which the insect was associated in both years. The caterpillars were noticed there in greatest numbers during Xovember, and both species were reported as destroying a number of garden crops, among which were cabbage, collards, turnip, ruta-baga, rape, peas and related plants, as also some other vegetables. Mature larva? were seen as late as the last week of Xovember. Among other office records are two which also have a bearing on the biology of this species. One of these was made by Mr. Theo. Pergande, who found the larva? in the District of Columbia feeding on blackberry and on flowers of a goldenrod (Solidago sp.). The other is a short note by Mr. F. M. Webster upon the rearing of the moth in spring from the seed pods of milkweed (Asclepias incar- nata) , near Lafayette, Ind. " The larva appeared to subsist upon the seeds, the pods being attached unopened to the wrecked plant." c October 21 the larva was found at Washington, D. C. We have no further records in regard to the habits of this species other than the capture of moths in the District of Columbia July 25, August 22 and 25, and September 2, and there are specimens also in the U. S. National Museum from Lewis County, X. Y., July 4, collected by O. Meske, and others from Xew Jersey without definite locality. The species is also said to occur at Portland, Oregon. It is interesting to note that among these specimens are inflated larva? and mounted heads labeled " pretty cutworm," which might be termed a manu- a The rearing jar was kept under somewhat unnatural conditions, at times too warm and dry, but the effect of one condition might have been counteracted by another, and the date of issuance of the adults was not far from that which would be assumed in nature — more likely earlier than otherwise. & Yearbook U. S. Dept. Agric. for 1898, p. 142. c Insect Life, Vol. II, p. 382, 1890. THE STRIPED GARDEN CATERPILLAR. 31 script name, as I do not find this insect mentioned under this cogno- men in print. With present knowledge of the species it can not properly be classified as a cutworm. Among the files of the Department of Agriculture there are a few notes which are of interest as showing the cycle of period- from egg to about the last stage of the larva. These notes were made in 1882 by Mr. Albert Koebele, and the mounts which were made with them are not sufficiently fresh for description. From these notes the fol- lowing is taken : Moths collected at sirup, near the District of Columbia. Septem- ber 16, were placed in a rearing jar with grass, where two batches of eggs were laid between 11 and 12 o'clock at night, one of these being deposited around the stem of grass. September 18 the eggs hatched, showing the egg period to be only 2 days. On the 21st the larvae had completed the first molt, making the first larval instar 3 days. September 23 the second molt was observed, which gives 2 days as the second larval instar. September 27 larvae changed their third skin, leaving 5 days as the period of the third instar. October 1 the fourth molt occurred, making 4 days for the fourth instar. By October 9 all the larvae had changed the fifth skin, when they developed cannibalistic tendencies and were removed to a larger jar. The period of this instar was 8 days. The remaining larva1 refused to eat and finally died, so that the complete life cycle could not be ascertained. NATURAL ENEMIES. Soon after bringing larvae in from the field some were noticed to be dying from fungous attack. In the asparagus Held- Estigrm m (Leucarctia) acrcea Dru, and Dissosteira Carolina L.. the salt-marsh caterpillar and Carolina locust, respectively, were also dying in con- siderable numbers, and it was conjectured that the disease might have originated with these and spread to the Mamestras. After the dis- eased caterpillars had been frequently removed, however, the fungous attack abated. Specimens of infected larva4 were referred to the Bureau of Plant Industry, and the fungus was identified by Mrs. Flora W. Patterson, assistant pathologist, as an undescribed species of Verticillium. At another time larva4 which showed sign- of dis- ease after capture were examined by Mrs. Patterson, who recognized the presence of the fungus Sporotrichwn minimum Speg. A Larva, when placed with diseased insects, including some of its own species, did not contract the fungous disease, from which it seems probable that the disease is not readily communicable, and hence of no use as a possible means of destroying this species. 32 SOME INSECTS INJURIOUS TO TRUCK CROPS. SUMMARY OF HABITS. From present knowledge of the caterpillar two generations annually are indicated, although only one has been observed. Moths have been reared by the writer in July and August and they have been captured out of doors during the same months and in September. From available data it would appear that an average life history would be about as follows : Egg period, 3 to 5 days ; first larval instar, 3 days ; second larval instar, 2 days; third, 5 days; fourth, 4 days; fifth, 8 days, and pupal stage, 7 to 10 months. Hibernation occurs in the pupal stage. The observed food plants include asparagus, cabbage, collards, turnip, ruta-baga, rape, peas and related plants, greenhouse violet, tobacco, grass, and blackberry. Of wild plants, golden-rod and milkweed have been observed, the larva attacking the flowers of the former and the seed pods of the latter. METHODS OF CONTROL. Although the early habits of this species as it occurs in the field have not been observed, there is no doubt that, like the zebra cater- pillar, the young when first hatched are gregarious for some time, and hence may* be easily discovered and destroyed by mechanical means or by arsenicals. All of the caterpillars of this class readily succumb to arsenical poisons, and for this species in its occurrence on asparagus and some other plants arsenate of lead is to be preferred. It may be used at the rate of about 1 pound combined with 15 to 25 gallons of water or Bordeaux mixture. If an adhesive resin soap, such as resin fish-oil soap, is added, it makes this mixture all the more permanent, and a single application is then all that is necessary. Paris green may be used in the same manner at the rate of 1 pound to 100 or 150 gallons of water. It is evident that this species, like the zebra caterpillar, does no particular harm as a rule in its first generation, but is much more abundant in the second or late fall gen- eration, when certain plants are injured by it. Owing to the diffi- culty of locating the larger larvae, it is evident that hand-picking would not be applicable for them in their later stages. U. S. £>. A., B. E. But. 66, Part IV. Issued January 27, IdO©. SOME INSECTS INJURIOUS TO TRUCK CROPS. THE LEAFHOPPERS OF THE SUGAR BEET AND THEIR RELATION TO THE "CURLY-LEAF" CONDITION. By E. D. Ball, Ph. D., Special Field Agent. INTRODUCTION. Ever since the introduction of the sugar beet into the intermountain region more or less loss has resulted each season from a condition called "curly-leaf," or "blight.*' (See PL I, fig. 1, j; Pis. II, III; PL IV, fig. 1.) Around Grand Junction, Colo., the beet growers have suffered frequent losses from this source. Supt. George Austin, of the Utah Sugar Company, reported a serious loss around Lehi, Utah, in 1897. In 1903 the beet crop in Sevier Count}7, Utah, was somewhat injured, the next year the damage was worse and more widespread, while in 1905 it extended throughout the State of Utah and the adjoining portions of Colorado and Idaho. Until 1905 the condition had been looked upon as a result of some fungous or bacterial disease, or due to a soil or climatic condition. During that season it was noticed for the first time that a leafhopper (Eutettix tenella Baker) was present in large numbers in the fields where this damage was the worst, and the writer, in connection with his duties as entomologist of the Utah Agricultural Experiment Sta- tion, commenced an investigation of the insect and it> relation to the damage. It was then too late to work out its life history, so most attention was paid to a study of its relation to the " curly-leaf " condi- tion and to experiments with remedies. This investigation was con- tinued in 190G and 1907, in cooperation with the Bureau of Entomol- ogy, and the life history was worked out. Owing to the small num- ber of insects appearing these two seasons, little more was done with remedies, but many new facts were learned in regard to methods of attack and the causes of the injury. The writer's attention was first called to the "curly-leaf" in August, 1900, by Prof. F. H. Shaw, then chemist of the Grand Junc- tion (Colo.) Sugar Factory. A careful examination was made at this time and again in succeeding year-, but no explanation was found 34 SOME INSECTS INJURIOUS TO TRUCK CROPS. for this condition. These examinations were, however, always made late in the season after the curly-leaf character had become general and after the greater number of insects had disappeared. Examina- tion of the beets always revealed a few specimens of Eutettix tenella along with other leafhoppers and miscellaneous insects, but never in sufficient number to cause suspicion. Late in June, 1905, reports began to come in to the Utah experiment station of the appearance of an insect in the beet fields of the southern and central portions of the State, and on July 8 the writer, in com- pany with Mr. George Austin, visited the fields around Lehi and there found the beet leafhoppers, associated with smaller numbers of false chinch bugs (Nysius) and leafhoppers of the genus Agallia, causing serious damage to the young plants, especially in the late-planted fields. From the size of the beets and the number of the beet leafhoppers present when first examined in 1905, the prediction was made that the insects would not be able seriously to retard the further growth of the beets. This prediction was based on the ordinary amount of damage done by insects of sucking habits. That the number of insects found would be able to injure or even seriously retard a very young beet was recognized, but that the same number could have any appreciable effect on large beets was contrary to all expectations based on a knowl- edge of similar attacks by Nysius, Agallia, and other sucking insects. The trouble soon afterwards appeared in the Cache Valley, Utah, and was under observation there throughout the remainder of the sea- son, while several trips were made to various parts of the State. Wherever it appeared it gradually grew worse, and although the year 1905 started with eveiything favorable in the early season, the Utah beet crop fell below the average about 75,000 tons. This, however, did not anywhere represent the entire loss, as both sugar content and purity of the beets harvested fell far below the average, entailing fur- ther loss to the sugar companies and bringing the total to more than half a million dollars. In Sanpete and Sevier counties, in the southern part of Utah, a large part of the acreage was abandoned early in the season, while the rest barely paid the expense of harvesting. In Utah County the crop varied from a total loss on a few late fields to a full crop, with an average of more than a half crop harvested. In the Cache Valley, in the northern part of the State, the loss was about one-third in tonnage, and in Weber and Boxelder counties less than that. In 1906 a very small number of leafhoppers appeared, and, as the season was cool, even where they were most abundant little damage was done. A careful study was made of the life history and distribu- tion of the species, and a number of tests were made of its injury to the beets. BjI. 66, Pt. IV, Bureau of En-omo.og/, U. S. Dept. of h j PLATE |. '. i . 't i ft A Leafhoppers (Eutettix spp.^ and Their Work. Fig. l —Eutettix teneUcu a, Adult: b, nymph; c, wing; • /. • . genitalia; /, eggs (greatly enlarged); .n beet stems; .;. small leaf • - el show- ing characteristic "curly-leaf " condition; t, enlarged section of back of am case of "curly-leaf," showing "warty" condition of veins, big. 2.— J a. Work of nymphs on lambsquarters: 6, work of nymphson sugar beet ! Eutettix scitula: Adult. Fig. 4.— Eutettix clariridn: a. Wing; b, head and i r c, d. genitalia. Fig. 5. — Eutettix nigridorsum: \V«»rk of nvmphson leaf of Helianthus. Fig. 6. — Eutettix dramiiiea: Work of nymphs on leaf of another Helianthus. Fijf. 7. — Eutettix in-nitu: Wmg. Fig. 8, — Eutettix stricta: a, 6, Genitalia. (Authors illus trations.) LEAFHOPPEBS OF THE SUGAB BEET. 35 THE BEET LEAFHOPPER. (Eutettix tend la linker.) DESCRIPTIVE. The adult (PL I, fig. 1, a) is a small, pale yellowish-green species, little larger than an Empoasca or Typhlocyba, with which it might easily be confused in the field were it not for the stouter build and greater activity. When fresh or when flying this leafhopper appears almost white, and for this reason it has often been called the "white fly." (Wing, PL I, fig. 1, c ; genitalia, PL I, fig. 1, d, e.) The eggs (PL I, fig. 1, /) are white, elongate, slightly curved and tapering at one end, and are thrust into the leaf stem in a slightly downward direction. At first they are scarcely visible (PL I, fig. 1, g), but as the stem grows they are pushed out with the opening up of the injured spot until at hatching time they are often half free (PL I, fig. 1, h). After the eggs hatch, the egg scars continue to en- large and remain throughout the season as irregular, elongate, crater- like swellings (PL I, fig. 1, i). The eggs are deposited on all parts of the leaf stem, usually one in a place. In the cages they were often placed close together, very likely in this case by different insects, however, and a number were inserted into the midrib and secondary veinlets of the leaf and a few into the leaf margin near the base. The nymphs (PL I, fig. 1, b) are very active, pale creamy white or variously colored forms. The commonest form is pale creamy in color with a brown saddle on the middle of the abdomen and various mottlings on the prothorax and wing-pads. Some have the same pat- tern with a reddish ground color, more are creamy yellow, and occa- sionally one is seen with a broad and somewhat irregular dark stripe down the back. When small the nymphs will be found most com- monly down in the unfolding leaves at the center of the beet, but as they grow older they spread out over the plant. FOOD PLANTS. The original food plant of this species is still in doubt. In the spring it was found on greasewood (Sarcobatus), sea-blite (Dondia), several species of Atriplex, Russian thistle, and rarely on other plants of these two families occurring on the waste land. As these places dried up, most of the leafhoppers went to the sugar beets in the areas under observation. In one case, however, the species was found in some numbers on greasewood during egg-laying time, which would suggest this plant as its original host. Its known distribution is all within the area in which this plant is abundant. 36 SOME INSECTS INJURIOUS TO TRUCK CROPS. DISTRIBUTION. This leaf hopper is apparently a native of the southwestern part of the United States. It has been collected from about the region of Denver, Colo., south along the edge of the mountains, through New Mexico, and west through Arizona, Utah, and southern Idaho to the coast in California and Oregon. Though confined to the mountain region, its distribution is restricted to the lower levels, and it is never taken on the mountains themselves. From this region it has not spread very far up to the present time. It was taken at Fort Collins and Lamar, Colo., in 1901 — in one case 100 miles north of its known habitat, on wild plants, and in the other an equal dis- tance east, but was rare in both situations. In Utah it has spread to the northern line of the State and into Idaho as far as that par- ticular beet area has been extended, while it has not as yet been taken from the wild plants north of Ogden, Utah. LIFE-HISTORY STUDIES. Search was made for this species as soon as the growing season commenced in the spring of 1906, but no specimens were discovered in the Cache Valley, Utah, up to the time the beets came up. A trip to Sevier County, Utah, at the time the very earliest beets were just showing (April 22) failed to disclose a single individual, either in the beet fields or in waste places or hedgerows adjacent to the beet-growing districts. The first specimens discovered this sea- son were found at Thompsons, Utah, May 3, feeding on Russian thistle, and a few days later the insect was found on the same plant and on an annual saltbush (Atriplex) at Grand Junction, Colo. Beet fields were examined at Grand Junction, Colo., May 8, and in Utah at Lehi, May 9; Smithfield, May 12; Garland, May 13; Lehi, May 17; Corinne and Penrose, May 22; and Provo and Lehi, June 1, without finding a single leaf hopper on any of them. The beets were not up at Lehi on May 9, nor at Smithfield, but the fields were examined carefully, especially where weeds were beginning to appear. Fields at Logan, Utah, were under observation during all this time and up to July 1, but no leafhoppers were found. RECORD AT LEHI, UTAH. On June 21 a field was examined at Lehi in which there was an average of one or two leafhoppers to a beet. They were all adults and two-thirds of them females. The beets in this field were from 6 to 10 inches across, and no sign of injury was observed. On exam- ining the other fields in the valley a very much smaller number of leafhoppers was found. Some fields had one individual to 10 beets, LEAFHOPPERS OF THE SUGAR BEET. 37 while some had none at all. The average would not have been more than one leafhopper to 25 beets. They were most numerous on the higher, drier fields, and on the early beets. Two patches of very late beets close to the first one visited had no leafhoppers at this time. Eight females from this field were dissected, and fully developed eggs were found in each one, 9 in one, 7 in another, and from 2 to 4 in each one of the others. Only large eggs could be seen with the lens used, and probably some of these were crushed while being re- moved. The fact that all females had fully developed eggs and that there were more females than males indicated that these adults had been out a long time and were not new ones of a brood that had just flown in from surrounding wild land. On June 29 a few were found in the late beets, but no nymphs were found anywhere. July 10 the adults were present in about the same numbers as be- fore, the females still containing eggs, and a few very small nymphs were found. July 23 the adults were slightly less numerous, and the nymphs from small to one-third grown and quite abundant. A few of them were nearly grown, but no fresh males could be found. More nymphs were found on the early beets, more " curly leaf '' on the late ones. August 3 the nymphs were mostly about two-thirds grown, some were small, and some full-grown. Large numbers of adults of the new brood were out, about half of the leafhoppers being adult at this time. August 14 the adults were abundant. The leafhoppers were nearly all adults or large nymphs, but a few small nymphs were still to be found. On August 29 the insects were mostly adult, males being still in the majority, but there was still quite a number of full-grown nymphs. Many females were dissected and a few found that had from 4 to 7 large eggs, but the rest had no sign of any. These few were probably the last remnant of the over-wintered brood of females. September 12 the adults were still common and more males than females were taken by sweeping. Large nymphs were still present in small numbers. Ten females were dissected, but no e. 1<» leaf- hoppers were introduced into cage 8; of these 23 were females, 55968°— Bull. G<>— 10 1 40 SOME INSECTS INJURIOUS TO TRUCK CROPS. apparently all fresh, 10 were males, and 7 were large nymphs, the aim being to get as many of the earliest ones of the maturing brood as possible without introducing any belated ones of the parent brood. By this method it was hoped to get the succeeding brood, if there was to be one, as soon in the cages as it appeared in the field, and thus establish a minimum time between broods. On August 14 this cage was examined, and all leafhoppers seen were adults. There were no signs of egg scars or of damage. On August 30 but few leafhoppers could be seen, and no egg scars or damage. On September 12 the leafhoppers were almost all gone, and no eggs had been laid, either in the cage or field, and dissection showed that the females had no visible eggs in the abdomen up to date. It was thought at this time that the adults would lay eggs in the fall and then die. Accordingly a new lot was started, as shown below. Cages 10 and 11 (large lantern globes). — On August 30, 30 leaf- hoppers were introduced into No. 10, of which 12 were females. In No. 11 one female and several males were introduced. On September 12 no egg scars could be found in either cage. Cages IS and i^-(silk scrim with a glass top). — On September 12, 20 leafhoppers, nearly all of which were females, were placed in cage 13. On October 20 the field of beets was harvested. The cages were removed and the beets labeled and sent on for examination. Each leaf and stem, and even the parts of the beet itself protruding from the ground, were examined carefully, but no sign of any egg scars could be found on these beets or on those from the previous cages. Many of the leafhoppers were alive at the time the cages were re- moved, and there seems to be no doubt that they must hibernate as adults. SUMMARY OF LIFE HISTORY. By the time the beets were thinned the leafhoppers began to appear in the fields and by the middle of June were well distributed. They gradually increased in numbers for some time after this. Egg laying began at Lehi, Utah, late in June and continued until late in August, each female depositing about 80 eggs, the period of deposition ex- tending through several weeks, the greater number of the eggs, how- ever, being deposited in the ten days preceding the middle of July. The nymphs appeared in small numbers by July 10, and were still to be found in small numbers in September. A great majority of them emerged from the eggs the last ten days in July and changed to adults some twenty days later. The first adults appeared from these nymphs the last of July and continued to increase in number through August. The egg stage in the cage experiments was between thirteen and fifteen days; the larval stage between sixteen and twenty-two days. LEAFHOPPERS OF THE SUGAR BEET. 41 ECONOMIC RELATIONS. The first fact observed in 1905 was that different fields were affected very differently, and much time was spent in studying conditions in an attempt to discover just what combination of factors was neces- sary to produce the " curty-leaf," so fatal to the beets. Even in the worst fields examined there would be here and there a beet that was apparently untouched and growing as usual, while in the best fields only here and there could an affected one be found. As a result of the season's observations there seemed to be little question that the " curly-leaf " condition was the result of the attack of the leafhoppers combined with the effect of a very hot, early season. In many places it was noticed that along the edges of the fields where the beets had any shade — such as would be furnished by a hedgerow, or even by a vigorous stand of sweet clover on a ditch bank — there would be a marked difference for the first few rows. In Sevier County, where many of even the early-planted fields were abandoned and where the rest averaged from 2 to 4 tons per acre, one field was seen that did not show much damage and yielded 12 tons per acre. This field had a block of tall poplar trees on the south and a row of equally tall ones on the west side. In other places it was observed that the fields that were the weediest had better beets than those that had been well cultivated. Under ordinary condi- tions the results in all these cases would have been just the reverse, and the only explanation that seemed plausible was that the shade of the trees and of the weeds kept the ground from becoming quite so hot and thus allowed the beets to overcome the effects of the leaf- hoppers. In ordinary practice the beets are not irrigated until they have made considerable growth; thus the taproot is forced to de- scend for water, and a long, symmetrical beet results, while if watered too soon the beets are short and sprangly. In one place, in 1905. it was found that the water had escaped from a ditch and irrigated one corner of a field much earlier than it had been applied to the rest, and this corner was the only place that was not seriously affected with the u curly-leaf.'' In another place the water supply failed just as they started to irrigate the field, and the remainder was not irrigated until a week later. The difference in the amount of " curly-leaf " on these beets showed plainly to the end of the season just how far the early water reached. At first these differences were attributed to the effect of the early water on the beet itself, but on further investigation a number of fields was found where subirrigation was depended upon entirely and where, ordinarily, fine beets were raised. In these fields the taproots of the beets were found to extend into a stratum of satu- rated soil and yet the beets were badly affected and continued to grow 42 SOME INSECTS INJURIOUS TO TRUCK CEOPS. worse throughout the season. The only explanation found for that condition was that, while the beet had plenty of water, still the top soil was dry and dusty, and the ground was as hot as in an ordinary field, while in the fields that were irrigated early the evaporation from the moist surface kept the temperature down until the beets were large enough to shade the ground. This would also explain the fact that everywhere in the State, except in Sevier County, the late beets were affected much worse than the early ones. In other portions of the State the early beets were large enough to shade the ground in the rows by the time the hot weather and leaf hoppers appeared. In Sevier County, on the other hand, the hot, dry weather came on earlier and the leaf hoppers were so much more numerous that even the earliest beets could not withstand their attack when exposed to the full force of the sun. The unusual numbers of the beet leafhopper were apparently largely the result of a winter and spring favorable for the preserva- tion of insect life, as almost all injurious insects were present in in- creased numbers during that season (1905). The leafhoppers had, however, evidently been increasing for several years and had even before this reached destructive numbers in Sevier County, as the beet growers there had been suffering increasingly from what they called " blight " for two years previous to this, and this increase in the number of insects, followed by a winter favorable to their sur- vival, resulted in the outbreak of 1905. The leafhoppers were present in every field examined in Utah that season, and occurred in the greatest abundance in the areas in which the " curly-leaf " was worst. The average number of adults of the over-wintered brood to a beet varied from 3 or 4 up to 10 or 15, and probably even more than that in Sevier County, judging from the number found there later. No serious damage was done where there were only the smaller numbers, and even where the damage was worst it seemed to depend more upon how early they appeared and the tem- perature and moisture of the locality at that time than on the actual number above an average of possibly 5 or 6 to a beet. In 1906 they appeared in very small numbers. The field at Lehi, Utah, where the experiments were conducted, was by far the worst found, and here they averaged only about 1 or 2 to a beet, while the average of the valley would not have been more than 1 to every ten or fifteen beets, and the average of the State was even less. A field in Boxelder County, Utah, was examined in August, 1905, in which the leafhoppers had recently appeared in large numbers, averaging 100 or even 200 in some places to the beet. The beets were large enough then to shade the ground, and the field was well irri- gated from that time on. Almost no curling of the leaves could be ! LEAFHOPPERS OF THE SUGAR BEET. 43 found in this field, and in the fall the yield was nearly up to the average. This was the only field examined in which the leafhopper- did not appear until after the adults had hatched out. On the other hand, many fields were examined in which the leafhoppers had been present early in the season but had almost disappeared after the nymphs had matured, and yet in these fields the curling continued to develop throughout the season and the beets grew worse instead of recovering. Spraying with kerosene emulsion was tried on a field in the Cache Valley, Utah, in 1905. This field contained numerous adults and nymphs in all stages. Four nozzles were used, each one set about 18 inches above the row and pointing obliquely down and forward, and just in front of them a bar drew the beet tops over and caused the leafhoppers to jump just as the spray struck them. An emulsion diluted with 15 parts of water had little effect on the adult.-, and only killed a few of the smaller nymphs. Most of the nymphs would kick about on the ground and some would become quite still, but a little later most of them would recover and hop away. An emulsion diluted with 8 parts of water produced the same effect on the adults that the weaker dilution did upon the nymphs, and killed the ma- jority of the nymphs that it struck. Many of the latter would, how- ever, escape the spray on account of the broad leaves of the beet, and the results were not considered entirely satisfactory. In the cage experiments it was expected that the number of leaf- hoppers necessary to cause " curly-leaf " on different-sized beets would be ascertained, but owing to the fineness of the gauze neces- sary to hold them the temperature and moisture could not be con- trolled and no ;' curly-leaf " was produced.5 The damp conditions of the cages also made it difficult to keep the insects for any length of time. In one experiment 1G leafhoppers. 12 of which were females ready to deposit eggs, were placed on a beet with a top 8 inches in diameter °This manuscript was originally prepared and submitted at the close of the season of 1906. Some revision was made to include the important farts of the work of 1907, but the main discussions, including the above paragraph, were written in 1906. since that writing " curly-leaf *' has appeared in cages arranged by Prof. E. 6. Titus in joint investigations with the writer. Mr. H. B. Shaw, assistant to Dr. C. O. Townsend, in charge of Sugar Beet Investigations, Bureau of Plant Industry, U. S. Department of Agriculture, lias also succeeded in pro- ducing "curly-leaf" under experimental conditions. He writes me under date of •October 23, 1908, that curly top or -curly-leaf" appeared in the cages on the experimental plat at Garland, Utah, in which lie Introduced the beet leaf- hoppers, and that later he sent a number of leafhoppers to the office i>t' Sugar Beel Investigations, Bureau i t Plant Industry, where •'• of them were placed in a cage with 11 young beets, «) of which showed distinct Symptoms of " curly- leaf" within five weeks after the insects were Introduced, 44 SOME INSECTS INJURIOUS TO TRUCK CROPS. and consisting of a dozen or more leaves. Over another beet of the same size a check cage was placed. Seventeen days later the eggs had just begun to hatch, and already the beet in the cage without any hoppers was nearly twice the size of the first one. The beet on which were the leafhoppers continued to grow for a week or more, then practically stood still, and on the seventeenth day it was apparently smaller than when examined five days before. Seven days later a large number of nymphs had hatched out, the outer leaves were dead, and the rest looking sickly; ten days later than this the cage was examined again and the beet was dead and dry, while the beet in the check cage had again doubled in size. Twelve leafhoppers and their eggs stopped the growth of a beet in less than two weeks, and they, together with their progeny, killed it in less than two weeks more. The same number of adult specimens of Agallia, Nysius, or Empoasca would scarcely have made an impression on a beet of that size. CHARACTERISTICS OF " CURLY-LEAF." The first symptom of " curly-leaf " or " blight " of the beet is a thickening of all the smaller veinlets of the leaf, giving it a rough- ened appearance on the underside. This is followed by a curling of the edge (PL III, fig. 1) and a final rolling up of the leaf (PL I, fig. I, j; PL II, figs. 2, 3; PL III, fig. 2), the upper surface always being rolled in. As this progresses the small veinlets grow still larger and more irregular, knotlike swellings appear at frequent intervals (PL III, fig. 2), and in extreme cases little nipplelike swellings appear, extending to a height of nearly one-fourth of an inch (PL I, fig. 1, k) . This will be noticed first upon a medium-sized leaf, gradually spreading to the younger ones, while at the same time the beet almost stops growing and a large number of fibrous roots are sent out (PL II, fig. 1). These roots are not confined to two irregular lines as in a healthy beet. The beet often continues in this way throughout the season, in bad cases it shrivels and dies, while in a few instances there is a partial recover}7 and a new set of leaves, though the sugar content remains very low. Many of the species of this genus of leafhoppers produce a discoloration or distortion of the leaves of their food plant. This appears to be of the same nature as the work of the gall-forming species, and is a process little understood. The wrinkling and folding of the leaves by some of the species is very similar in appearance to the work of some gall-forming aphides. Some species also produce a change in color similar to that produced in many galls. In the case of Eutettix strobi (PL I, fig. 2 «, b) and E. scitula on the Chenopodium or on the sugar beet and of E. nigridorsum and E. straminea (PL I, fig. 6) on the Helianthus the discoloration appears as Bui. 66, Pt. IV, ^rnology, U. S. Dep- Plate II. Work of Eutettix tenella on Sugar Beet. Fig. 1— Three '• curly-leaf " beets, the result of attack by Eutettix tenella, and one normal beet from the same Reld, showing difference in size. Figs. 2, 3 " Curl v-leaf" beets as Been in the field. Fig. L— Normal beets from same field. (Original ) Bui. 66, Pt. IV, Bureau of Entomology, U. S. Dept. of Agriculture. Plate III. Work of Eutettix tenella on Sugar Beet. Fig. l.— a Largebeet becoming "curly." Fig. 2.— Back of a leaf affected by "curly-leaf, snowing "warty" condition and curled edges. (Original.) LEAFHOPPERS OF THE SUGAR BEET. 45 soon as the little nymphs begin to feed, and this is soon followed by the distortion of the leaf in a certain definite way in each case. That this is not caused by the mechanical injury of the puncture or due alone to the loss of sap seems to be abundantly proved by the fact that the Chenopodium is often attacked by other sucking insects in much larger numbers without producing either the red pigment or the gall-like distortion. The fact that a certain characteristic color and appearance are always produced by a given species, no matter whether on a Chenopodium or on a sugar beet, and that the color and form vary for the different species of the same genus even when working on the same plant, would indicate that there is some definite agency back of it all. It has also been noticed that in all this group the greatest amount of damage is done in hot, dry situations. Whether or not the " curly-leaf " condition is entirely the result of the change in the beet caused by the attack of the beet leaf hopper is still an open question, but that there is some relationship between the leafhopper attack and the " curly-leaf " does not seem to admit of a doubt in the light of the facts brought out in the investigations. The amount of damage in a given valley was directly proportional to the number of leaf hoppers present, the injury appeared only after the appearance of the leafhoppers, and the " curly-leaf " condition is known to occur only on beets growing wdthin the range of this insect. Attention was not called to the damage early enough in 1905 to ascertain whether or not the " curly-leaf " appeared before the first appearance of the nymphs. At Lehi, Utah, the " curly-leaf " ap- peared very soon after the first nymphs. In the Cache Valley, Utah, the nymphs were common by the time the first curling was noticed. In 1906 very careful watch was kept in all parts of the State for the very first sign of leaf -curl, and in no case did it appear (except on the mother beets) until after the nymphs began to hatch out. In fact, in almost every case examined the cast skins of nymphs could be found on the back of curled leaves, while on healthy beets these were very seldom found. In all observations of both years more leafhoppers were found on the curled beets than on others. At first this was thought to show a gregarious habit in the adult, but it may be due to the fact that a given female lays most of her eggs on a single plant and the nymphs tend to remain there. In Eutettix strobi and the other leaf-curling forms, where the nymphs are brightly colored and depend on their discolored spots for protection, it is not unusual for a given nymph to pass its whole life on a single leaf, or on two or three adjoining ones; in most eases but a single nymph will be found on a plant, and sometimes the adult and the nymphal skin of each stage may be found under a single leaf. Tt is very likely that the same habit persists in Eutettix tenella and that this fact, in part at 46 SOME INSECTS INJURIOUS TO TRUCK CROPS. least, accounts for one beet being badly affected while the adjacent ones are unharmed, fin the case of Eutettix strobi and its allies, where most of the leaves of a small plant are affected by the dis- tortion, the plant usually shrivels up and dies, but where only one or two leaves on a large plant are distorted the plant does not appear to be affected at all, and in no case does the color appear in any of the new leaves. In several cases small beets have been seen in which every leaf has been deformed by the work of strobi, and they had apparently stopped growing. In the case of the " curly-leaf," however, the abnormal condition apparently spreads from leaf to leaf until finally the whole plant is affected, even though the leafhoppers may have disappeared before the process is complete. This was abundantly demonstrated by the mother beets set out in the spring of 1906. These beets were selected from the best-looking beets of 1905, and would naturally have been ones that showed little or no effect of the " curly-leaf " the season before. In every case observed the first leaves sent up by these beets were as curly as the average of the year before, and most of them formed stunted lettucelike heads, and later withered and died. Some, however, survived through the season, and a few sent up stunted blos- som stalks, but as a seed crop they were an entire failure. This curl- ing took place before any leafhoppers were found in the beets, and in rows adjoining young beets that were not at all affected and did not become affected during the season. This would indicate that the agency, whatever it may be, that causes " curly-leaf " remained in the beet itself over winter and was transmitted to the first leaves in the spring. In early September, 1907, the sugar-beet region around Spreckels, Cal., was visited by the writer and a number of cases of what was commonly called " blight " or " curly-leaf " were examined. These, however, proved to be quite different in character from the " curly- leaf " condition caused by Eutettix tenella. The leaves of the beet were found to be covered with pale spots, the edges were turned down instead of up, and the whole appearance was quite different. A care- ful search was made over many acres for specimens of tenella, but none was found; instead a species of Empoasca was always found associated with this appearance of the beets. The matter will be dis- cussed further in connection with that species (p. 51). OTHER RECORDS. Prof. E. G. Titus reports that on a trip through the sugar-beet regions of the West in September, 1904, he found Eutettix tenella at La Grande and Echo, Oreg. At La Grande little damage was done, while at Echo one field of 10 acres was so seriously injured by what Bui. 66, Pt. IV, Burea, I El Plate IV. Work of Eutettix tenella on Sugar Beet. — Cages used in tlu> life-history Pig. 1.— A field of beets destroyed by "curly-leaf." Fig experiments. (Original, i LEAFHOPPEKS OF THE SUGAR BEET. 47 was then called "blight" that it was not harvested. Many of the beets had died and the rest were small and stunted, while the leaf- hoppers could be swept up in numbers. In California " curly-leaf " conditions were seen by Professor Titus at Oxnard and Spreckels and reported to be quite serious on the higher lands back of Salinas. Whether this was the true " curly-leaf " or the type found there this year was not determined. In August, 1907, another trip was made by him through the same territory and a few specimens of Eutettix tenella taken at Payette, Idaho. Little damage was being done that season, but field men re- ported considerable loss in 1905 in both Payette and Blackfoot, Idaho. A few E. tenella were taken at Union, Oreg., and Echo, Oreg., in August, 1907, only slight damage shoAving in either place. Large nymphs were taken with the adults. In California a number of places were visited by Professor Titus in August, 1907, but no specimens of Eutettix taken. In September another trip through the California districts was made, and a few specimens of E. tenella were taken at Chino on the 13th. Xo very definite cases of " curly-leaf " were noticed. ECONOMIC SUMMARY AND PROPOSED REMEDIES. The " curly-leaf " condition or " blight " of the sugar beet, as it occurs in Utah and the surrounding region, appears soon after an attack of the beet leafhopper (Eutettix tenella Baker). Its severity is conditional upon the number of insects present, upon the time of their appearance, upon the size of the beets, and upon the temperature of the surface soil, together with the temperature and moisture of the surrounding air. More should be known about the places of hibernation and early spring history of this insect. It could not be found in the rubbish around the fields in early spring, and only a few specimens were found in waste places up to the time they appeared on the beets. When once the place where the greater number of them pass the winter is discov- ered, it may be possible to destroy them there or on their spring food plants before the}' migrate to the beets. After they have appeared on the beets it will be necessary to be very prompt in the matter of remedies if the injury is to be prevented. A thorough -praying with kerosene emulsion at a strength of 1 part of the stock solution " to .""> parts of water would destroy most of the insects that it hit. and by using a drag in front of the nozzles to turn the leaves over and cause the insects to jump, most of them could be reached. Where the insects "For directions regarding the preparation ami usi> of kerosene emulsion see Fanners' Bulletin 127, V . s. Dept of Agriculture, pp. 20-21, and Circular 80, Bureau of Entomology. 48 SOME INSECTS INJURIOUS TO TRUCK CROPS. were coming in in numbers this spray would need to be followed by a second one 10 days later. Several mechanical devices have been used to catch different leaf- hoppers, and no doubt several of these could be used against this insect with advantage. The tar pan, or " hopper-dozer," drawn over the beets two or three times in the first few weeks would capture a large number of them. The females, before the eggs are laid, are quite heavy and do not jump or fly as readily as the males and would be easily caught. A modified form of this machine, consisting of a couj^le of tarred wings to be drawn along on each side of a row of beets, while a drag agitated the tops and caused the insects to fly, would probably capture more than the simpler tar-pan. If the insects appeared while the beets were quite small, they could be largely destroyed by rolling when the weather was cold or damp and the insects sluggish. A number of preventive measures may be used to assist the beets in withstanding the attack of the leafhoppers. In some sections early planting will produce beets large enough to shade the ground by the time the beet leafhoppers appear, and thus reduce the temperature below the danger line. In a few places, like the Grand Junction dis- trict in Colorado and Sevier County in Utah, early planting alone would not avail, as the insects appear soon after the earliest beets come through the ground. For such sections early and frequent irri- gations would assist in keeping the ground cool until the beets grew large enough to shade it and thus take care of themselves. All preventive measures will depend for success upon some method of controlling the temperature in the field so that the ground may not be hot and dry at the time the leafhoppers appear. BIBLIOGRAPHICAL REFERENCES. 1895. Gillette, C. P., and C. F. Baker. — A preliminary list of the Hemiptera of Colorado. is a western species occur- " Science Vol. X. p. L66, L887. *Bul. 23, o. s.. Div. Km.. V . S. Dept Agric, p. 17. 1891 «' Bui. 80, 111. Agric. Exp. Sta„ p. 424, UKH). 50 SOME INSECTS INJURIOUS TO TRUCK CROPS. ring in Colorado and Utah and has been found on sugar beets only at Grand Junction, Colo. The adults of the species are almost in- variably found on poplar trees, and it seems probable that the eggs are deposited on twigs of the trees and that the nymphs drop to the ground to find a home on the Chenopodium. The adults of Eutettix strobi and E. seminuda are often found on trees and may have the same habit. In the case of E. strobi and E. scitula, nearly all in- stances of bad infestation have been near trees. In the case of E. scitula these have been poplars, but two of the worst instances of injury from E. strobi were alongside apple trees. Eutettix seminuda Say. — Eutettix seminuda is a white insect with a brown saddle. It occurs from Kansas east to the Atlantic coast. The nymphs are pale, with a brown saddle on the abdomen and some brown on the thorax. Nothing is known as to their native food plant, but from the close relationship to the preceding species it is likely that it will prove to be a Chenopodium. There are two broods in a season, the first one appearing slightly earlier than in the case of E. strobi. Eutettix seminuda has been reported on beets in Illinois. It does not occur in the "West, where the writer has worked on beets. Eutettix clarivida Van Duzee (PL I, fig. 4, «, b, e, d). — Eutettix clarivida is a green species with four black points on the margin of the vertex. It occurs very commonly on the shad scale {Atriplex con ferti folia) and on one or two other species of the same genus in the arid regions. It has been found on beets at Grand Junction, Colo. The nymphs are green, with two black spots on the vertex. The life history is not known. Eutettix insana Ball (PL I, fig. 7), E. albida Ball, and E. pauper- culata Ball occur on different species of Atriplex in the arid regions, and may be expected to occur on the beets. Eutettix stricta Ball (PL I, fig. 8, «, b) is an Arizona species and the nearest relative of E. tenella that we know. There is probably more danger from this than from any other species of the group, if the sugar beet should be introduced within its range. All the species of Agallia in a given section will be found attack- ing the sugar beet more or less. Several of the species seem to be almost omnivorous in food habits, but where they do show a pref- erence it is for the relatives of the beet. For two of the species (cinerea and bigelovice) a definite food plant is known, and in both cases they are close relatives of the beet. The species of Agallia are divided into two groups, based on structural and life-history charac- ters. In one group, which includes sanguinolenta, uhleri, cinerea, and bigeloviw, they seem to prefer warm and rather dry situations, the adults hibernating and spreading over the beet fields in the spring in time to lay their eggs and produce their single brood of young there. LBAPHOPPERS OF THE SUGAB BEET. 51 Agallia sanguinolenta Prov. is the mosl abundant species of the ge- nus in the western country and is found in all fields. Together with A. uhleri this species has been observed to do considerable damage in the Arkansas Valley, in Colorado, and around Lehi, in Utah. The nymphs appear early in Juno and mature in the last half of July and the first half of August, a few running on through the month. Agallia cinerea Osborn and Ball is found almost exclusively on the "shad scale" of desert regions, and from this adults often fly to near-by fields of beets. It was common at Grand Junction and Loma, Colo., and at Monroe, Utah. Under the hot desert condi- tions the nymphs appear in June and mature the last half of July, while on the beets they do not mature until some time later. Agallia bigelovice Baker occurs in abundance on a tall species of sea-blite (Dondia) growing on alkaline soil, and has been found in the beet fields at Grand Junction and Palisades. Colo. Agallia quadripunctata Prov. and .1. novella Say belong to the other group of the genus and pass the winter as partially grown nymphs, which change to adults in late May and June. The nymphs appear again in August and develop slowly until fall, when they hibernate. These two species and A. sanguinolertfa are discussed by Osborn and Ball (Iowa Experiment Station Report for 1897, p. 112), the nymphs and adults being figured and the life histories given. The dates given there are, however, too early for western conditions. This group thrives best in damp situations where rank vegetation abounds, and will not do any serious damage to beets unless planted alongside places of this character, from which the nymphs can mi- grate in early spring. By the time the adults are mature and ready to fly, the beets are well started and beyond their injury. Empoasca sp. — A large number of adults of a small green Em- poasea were found on sugar beets at Spreckels, Cal., in early Septem- ber by Prof. E. G. Titus and the writer. The beet crop was not seriously injured, but a number of beets were found in which there was a slight curling of the leaves resembling " curly-leaf." except that in this case the edges of the leaf turned down rather than up. and the surface of the leaf, instead of being roughened, was covered with small pale spots. This pale spotting of the leaves is quite charac- teristic of the injury of the Empoascas and their relatives and is com- monly seen on apple and rose leaves. The insects were all adult- at this time, so that it was impossible to be certain that they had bred on the beets, but from the appearance of the leaves it is probable that they had. The nymphs of nearly all of this group are slender, pale- greenish forms and are found mostly on the underside of the leaf, while the white spots caused by their punctures show more plainly on the upper surface. 52 SOME INSECTS INJURIOUS TO TRUCK CROPS. Professor Titus reports finding an Empoasca common on beets at Chino, Cal., in August, 1907, and states that the beet leaves showed the characteristic spotted appearance, but that no curling was noticed. In his trip in 1904 Empoascas were noticed in several places in Cali- fornia, and quite serious damage from " blight " or " curly-leaf " was found in a few places, but the particular nature of the injury was not observed. The Empoascas nearly all pass the winter as adults, hibernating in rubbish and sheltered places near their food plants. In the spring they feed on anything that offers until their food plants start, and then they gather on them, laying eggs in early summer. The young nymphs feed on the underside of the leaf and are quite active and keep out of sight. Spraying with kerosene emulsion, 1 part of the stock solution to 8 parts of water, proved to be a satisfactory remedy for an Empoasca on potatoes in Iowa some years ago, and no doubt could be used on the beets with success. Burning off rubbish around the field in the late fall would probably reduce their numbers. CONCLUSIONS IN REGARD TO " CURLY-LEAF." As a result of the above investigations, it appears that there are at least two distinct kinds of " curly-leaf " that have been confused under one name. One, in which the leaves become rough and warty and curl up and in which the beet is stunted and does not recover ; the other, in which the leaves remain smooth but show numerous pale spots and in which the edges turn down, and in which, as far as known, the injury is confined to the leaves attacked. The first-mentioned kind of " curly-leaf " occurs from Grand Junction, Colo., west to the Pacific coast and is the one that has been seriously injurious in the inter- mountain region. This condition is brought about by the attack of the beet leaf hopper (Eutettix tenetta), and will, no doubt, be confined, for some time at least, to the southwestern part of the United States, the native home of this insect. The second kind of " curly-leaf " has been found in California quite commonly, and doubtless will be found to occur sparingly at least in the eastern part of the United States, or wherever an Empoasca attacks the sugar beet. Besides these two types of this injury it is quite possible that in rare cases other types with still other causes have been seen and not recognized at the time as distinct. Investigations in the California field have been so meager that it is impossible to say as yet which type has caused the greatest injury. In the intermountain region, where most of the work has been done, practically all the injury is known to have been caused by the first type. C. S. D. A., P.. B. Bui. 66, Part V. Issued January 28, 1909. SOME INSECTS. INJURIOUS TO TRUCK CROPS. THE SEMITROPICAL ARMY WORM. i Prodi iiiu eridania < 'ram.) By F. H. Chittenden and II. M. Russell. INTRODUCTION. During the summer of 1907 a smooth or hairless caterpillar {Pro- denia eridania Cram.) related to the cotton cutworm came under the observation of the junior author at Orlando, Fla. It was observed attacking the foliage and, in many cases, the stems and fruits of all forms of garden truck grown in that vicinity, the list including tomato, potato, sweet-potato, eggplant, pepper, okra. collards. and cowpeas. The infestation was of considerable severity, and great in- jury was done in fields and gardens in that and in some other regions of Florida, notably at St. Augustine and on the west coast of the Manatee River. What is believed to be the same specif- was reported injurious in Porto Rico by Mr. W. V. Tower. Aside from a brief notice which has been made of the present invasion there does not appear to be any other record of the injurious habits of this species; hence the following account has been prepared for publication by the senior author. The chapters on recent injuries, natural enemies, and experiments with remedies have been compiled from the junior au- thor's notes. The technical descriptions of the egg and larva have been prepared by Dr. H. G. Dyar, while other assistance in the prep- aration of this article is duly acknowledged in its proper place. In ordinary seasons the species under consideration confines itself largely to weeds, among which are the poke-weed, spiny amaranth or careless weed of the South, and a wild Solatium. It has habits different from those of the northern cutworms and can scarcely be classified with the climbing cutworms, although it has the climbing habit. It has a decided tendency to travel in armies like the army worms and i- practically confined to semitropical region-. It is remarkable ;is being injurious throughout the warm season and breed- ing continuously, there being evidently at least four generations a year in nature. 58 54 SOME INSECTS INJURIOUS TO TRUCK CROPS. DESCRIPTIVE. The adult is a noctuid moth, and while the larva is quite readily referable to the genus Prodenia, the moth has little of the appear- ance of our other two North American species." The moth. — The adult or moth has a wing expanse of nearly 1J inches (33-38mm) ; the fore-wings are dull gray, sprinkled and dotted with brownish and black scales forming a pattern as shown in figure 8, d. There is considerable variability in these markings, some individuals having a strongly marked reniform spot, a very prominent blackish posterior marginal line, and a similar black line 'ig. 8. — The semitropical army worm {Prodenia eridania) : a, Egg-mass on leaf; b, egg, much enlarged, showing lateral view at right and top at left ; c, section of egg ; d, moth ; c, dark form of larva nearly grown ; /, g, larva, full-grown, a, d-g, En- larged; 6, highly magnified; c, more magnified. (Original.) on the latero-posterior margin. Individuals also occur in which there is a straight, broad, jet-black dash or band beginning at the middle of the fore-wing and extending to the lateral margin. This is the nigro fascia of Hulst. The hind- wings are pearly white above, this pearly luster being still stronger below. The body is brownish gray and the antenna? are yellowish brown. The darkest forms of this species are marked very much as in the genus Acronycta. The eggs. — The eggs are deposited in irregular masses, as shown in figure 8, a, closely placed together, sometimes in two layers and a Prodenia otviithogaUi Guen. ("cotton cutworm") and P. commelinw S. & A. THE SEMITBOPICAL AHMV WORM. 55 covered with whitish down, from the body of the female. They are distinctly green when first deposited and have the appearance illus- trated ai A and <■. The larva, — The caterpillar resembles that of the other two species of Prodenia sufficiently to be naturally referred to that genus, and it is subject to similar variation in color. The ground color is dark grayish in pale individuals and nearly black in the dark form-. These latter, especially when approaching maturity in the penulti- mate stage, are sometimes so dark as to resemble Mamestra. The body is ornamented with a narrow, slightly interrupted, median yel- low longitudinal dorsal stripe, a similar slightly wider dorso-median stripe, and a wide and brighter yellow substigmatal -tripe, which becomes obscured in the thoracic segments of the penultimate stage. In the very dark forms the triangular velvety dorsal spots character- istic of the genus can scarcely be seen, and in the paler form- they are seldom as distinct as in the other two species. When full-grown the larva measures about an inch and a fourth to an inch and a half in length (25-37mm). and the width varies from one-fourth of an inch to a little larger. The head measures nearly 2.5mm. The mature larva is illustrated at f and g of figure 8 and a dark form nearly grown at e. The pupa. — The pupa resembles closely that of Prodenia comme- lince. The head and abdomen are well rounded. The color is mahogany-brown, with the head, spiracles, and anterior edges of the abdominal segments darker. The surface is smooth and shining, with the anterior edges of the abdominal segments finely punctured. The anal segment terminates in a two-spined cremaster-like process. Length, 16-18 mm: width, 5-6 mm; length of head to end of the wing- cases, 10mm. The following technical description of the egg and larval stages was kindly contributed by Dr. H. G. Dyar. rBCHNICAL DESCRIPTION OF HIK BOG AND LARVAL STAGES. The egg. — Hemispherical, smooth, pale green, shining; ribs very tine. obscure, numerous, ill-defined, radiating from the micropyle; cross-strise imper- ceptible. Diameter, o.(>mm. Laid in a patch, covered by a thin layer of whitish Wool. Stage I. — Head rounded, bilobed, month pointed, whining greenish-black; eyes black, month brown; width about o.:>,m,ii. Body robust, uniform, joint 12 Blightly enlarged, foot of joints 7 and B a littlo Smaller than the others and Dot used in walking; translucent greenish, cervical shield, lei: plates, thoracic feet, anal plate, and the large round tubercles shining black: tubercles i and ii of joint L2 in a square; seta> rather coarse, moderate, black, simple. si, i;/, ll. Head rounded. Blightly bilobed. the vertex level with joint 'J. shin- in.- luteoiis. blackish shaded over the vertices of the lobes; ocelli black, month brown, width. 0.4""". Body somewhat thickened at joints ."• and 12, feel normal. equal; greenish luteous, cervical shield and anal plate blackish Infuscated; 56968°— Bull. M— 10 5 56 SOME INSECTS INJURIOUS TO TEUCK CROPS. tubercles rather large, low-conical, black; leg shields slightly smoky; tubercle vi present; a large red blotch around tubercles i and iv on joints 5 and 12; setae short, black, stiff; traces of a white dorsal line showing especially by the cut between the red blotches at tubercle i of joint 5 ; no other lines. Stage III. — Head rounded, the vertex just within joint 3, pale reddish over the lobes and sides, luteous on the face, shining, very small in proportion to the body; width, 0.6 mm. Body robust, slightly thickened at joint 5, more so at joint 12 ; feet normal ; pale green ; a straight dorsal and a subdorsal white line and traces of a broken lateral one ; subventral region slightly pale, without defined line; tubercles small, black; a large, vinous, somewhat elevated blotch on tubercles i and iv on joint 5 and on tubercle i on joint 12, more diffusely about the spiracle on joints 11—12 ; anal feet reddish ; cervical shield small, infuscated, cut by three white lines ; anal plate blackish ; thoracic feet blackish, abdominal ones greenish. Stage IV. — Head rounded, rather quadrate, not notched, the clypeus high, vertex even with joint 2; pale red, paler on the clypeus, ocelli and antennae dark; width 1.0 mm. Body robust, thickened at joints 5 and 12, feet equal; blackish olivaceous, dorsal and subdorsal lines straight, yellowish white, edged with vinous dottings ; traces of a lateral line ; subventral region paler below the spiracles, especially after joint 5 ; large blackish-red blotches at tubercles i and iv on joint 5 and on joint 12 and tubercle i and stigma tally on joints 11-12 ; white dotting in the ground color most conspicuous stigmatally ; thoracic feet black, abdominal ones pale, anal pair reddish. Stage V. — Head quadrate, rounded, slightly bilobed, shining light red-brown, the clypeus high; ocelli and setae black; width, 1.6mm. Body thickened at joints 5 and 12, feet equal, normal, the abdominal ones pale, slightly infuscated, the thoracic ones black-ringed ; dark gray to black, strigose-dotted with white ; dorsal line narrow, subdorsal broader, straight, even, yellowish white, centered with reddish mottlings, cutting the sooty-black cervical shield, but not the anal plate; a quadrate black patch between the lines on joint 5, a small angular one next the subdorsal line on all the other segments, large on joint 12 and shaded across; a narrow white-dotted lateral line, scarcely different from the dots of the ground color ; subventral band straight, yellow-white, broad, broken at joint 5, reddish-filled around the spiracles, black spots at tubercles iii with a distinct white dot below ; subventral region of thorax blackish, of abdomen paler, white- dotted. Stage VI. — Head rounded, quadrate, about as high as wide, slightly bilobed, the vertex level with joint 2; clypeus high and large; red-brown, darker reticulate, mouth parts concolorous, ocelli black ; width 2.1 to 2.4 mm. Body robust, cylindrical, tapering from joint 5 to joint 2, the head small ; joint 5 slightly, joint 12 distinctly, enlarged and abruptly tapered to joint 13; black, strigose-dotted with white ; cervical shield deep black, white-dotted, cut by three white lines ; anal plate similar, small, cut by the dorsal line only ; dorsal line narrow, black-dotted and broken, yellowish white, reddish on the centers of the segments; subdorsal line broader, straight, yellow-white, reddish centered on the segments, with a median row of gray dots, but not incised on the margins ; a row of segmental black triangles above it, free of white dots, largest on joint 5, the one on joint 12 now scarcely larger than that on joint 11 ; upper half of the lateral area grayer, with many white dots, lower half blacker, with few dots on joints 5 to 13, separated by a row of brighter dots representing the lateral line ; on joints 2 to 5 this distinction is weakly developed ; spiracles in a blacker shade with a white dot above tubercle iv ; substigmatal band broad, even, undulate, weak and broadly gray, centered on joints 2 to 5, fading out at THE SEMTTROPICAL ARMY WORM. 57 joint 5, sharply reappearing at joint 5 posteriorly, then pale yellow, centered with blackish mottlings at the centers of the segments and red above these; Bubventral region black-shaded, strongly so on joints 2 to 5, weakly on the ab- domen, white-dotted, paling to the venter; thoracic feet dark brown, the ab- dominal ones pale brown, shining; a single cylindrical, round-tipped neck gland reaching to the end of the labial palpi ; crochets of abdominal feet in a single row, dark; tubercle iv sligbtly above middle of spiracle on joint 7. [Harrison G. Dyar.] ORIGIN AND DISTRIBUTION. This is a Lower Austral form and probably of tropical origin. In the National Museum are specimens from Cocoanut Grove, Crescent City, and Orlando, Fla. The species is also recorded from Talla- hassee, and reported from St. Augustine and the region about the Manatee River in Florida. From Texas we have specimens from Bos- que County (Belfrage) and Dallas, and there are specimens col- lected at Pernambuco, Benito Province, Brazil, by Mr. Albert Koebele. Dr. J. B. Smith records the insect from Georgia and Central and South America, and Grote records it from California. This indi- cates a range extending from Brazil to Mexico, Central America, and the Antilles, and from Florida westward through the Gulf region and Texas to California. LITERATURE AND HISTORY. Considering the fact that this species is really common in the South and that it feeds gregariously and voraciously, it is somewhat remarkable that it has not hitherto attracted attention by its depre- dations. The moth was described by Pierre Cramer in 1782. 1 a Its natural food plants were known to Smith and Abbot, who wrote of it in their classic work published in 1797.2 The illustration ac- companying that work, though over-colored as usual, depicts a per- fectly recognizable moth of this species but a too-brilliant and light- colored larva. Light and dark forms of the moth are figured. The species is mentioned as PhaloBna phytolaccce and is compared with the related Prodenia commelince and Laphygma frugiperda^ which form the subject of the two plates and pages immediately preceding the account of phytolaccce. As Smith and Abbot's work is not accessible to many, the following copy of their account of this insect is republished: IMIAI..KNA PHYTOLACCA Poko-\Y('0(t llioth. Phytolacca decandra. Linn. Virginian poke-weed. Ph. Noctua spirilinguis cristata, aiis deflexis: primoribus rusco striatis puncto obscuro margine postico nigro macula to; anterior] punctato. " Numbers in superior type refer to corresponding numerals in the appended bibliographical list (i». TO). 58 SOME INSECTS INJUKIOUS TO TRUCK CROPS. Feeds on the Poke, Careless, &c. It went into the ground July the 5th, and came out the 16th. I once met this caterpillar in such abundance, that among a great quantity of Poke plants there was scarcely a single leaf untouched ; most of these caterpillars, however, were fly-blown by a kind of Ichneumon. The moth is rare. This is allied to our Ph. frugiperda and Commelinw. Between the under wings of all these there is the greatest affinity. Their pupae too are of a similar bright red color, and their smooth-striped caterpillars have much resemblance to each other. KECENT INJURIES AND BIOLOGIC NOTES. On May 14, 1907, this species was observed on the leaves of tomato in the truck garden of Mr. C. M. Berry, at Orlando, Fla., where it was eating holes in the leaves. Numbers of plants, here and there, were infested and in most cases the entire plant was injured. The same larva was observed on pokeweed {Phytolacca decandra), and afterwards on spiiry amaranth {Amaranthus spinosus) . By May 20 the larvae were scattering and had grown rapidly, some being an inch long. While young, these larva? feed on the underside of the leaf, but with larger growth some were noticed feeding on the upper surface as well. May 24 an egg-mass was found on a leaf of the spiny amaranth, laid in two sections on the under surface, one on each side of the midrib. One mass had hatched at this time and the larvae were be- ginning to eat pinlike holes through the leaf. On July 3 a field of Irish potatoes was found to be very badly in- fested bj these larvae. They were now nearly full-grown and had stripped the potato vines, many being observed crawling away from the field in all directions. On one side the}7 infested a garden at least 600 feet away, and were feeding upon eggplant, pepper, okra, and castor-oil plants. Some interesting notes were made on the abundance of this species in this potato field. On a single young plant of Amaranthus, 41 larvae were counted, and as many as 314 on a plant measuring 6 feet in height. A careful estimate of the larvae on 10 plants of careless weed, not over 6 feet in height, gave a total of 1,300 individuals. (See fig. 9.) To illustrate the voracity of these larvae, where any potatoes were exposed, they were soon covered by the larvae and the entire contents eaten out so that they were rendered worthless in about ten minutes. About this same date, July 3, the larvae were reported making quick work of amaranth; whenever a branch became broken from any cause, larvae entered at the break and excavated tunnels several inches in length. Pokeweed was entirely stripped of leaves, the stalks and the shoots being eaten off at the outer end. Potatoes dug THE SEMITROPICAL ARMY WORM. 59 at this time were frequently found full of holes, the work of these larvae. The following day, July 4, the amaranth was almosl com- pletely denuded, illustrating the rapid work of this species when in large numbers (see figs. 10, 11). By July 8 the larvae had almosl completed their work in the field, after having eaten everything clean. Many were full grown and had commenced to enter the ground. July 9 the potato field was stripped, the vines were dead and dry, and the larvae had almost disappeared. The ground was full of pupae, none of them at a greater depth than 4 inches, and in IhM Pig. 9.— The Bemitropical army worm (Prodenia eridania) ; Work of larvae on "careless weed " in potato field; 311 larva? wore on this plant when photographed. (Original, i many eases only 2 inches. Upon digging into the hills, it was found that they did not average more than four good-sized potatoes to the hill, and in many eases these had been rendered useless by the inroads of the larva1. (This crop averaged small because of Late planting.) Many Larvae were found feeding on sweet potatoes at Mr. John M. Cheney's place at this time, most of them still in young stages, A few fully matured larvae also were found, showing the overlapping of the two generations; in fact, observations conducted both in the 60 SOME INSECTS INJURIOUS TO TRUCK CROPS. field and at the insectary at Washington, D. C, show that this species is undoubtedly a continuous breeder, as in the case of the variegated cutworm {Peridroma margaritosa Haw.), the larva? being present in the field throughout the long summer season of the South. July 30, by request of the county commissioner, Mr. H. H. Dick- son, the junior author went to the County Home and found a sweet- potato patch badly infested, thousands of larvae present, and the leaves turning brown and drying out. Superintendent Harris stated that an earlier brood did great damage to cowpeas, but this could not be verified by specimens. In the sweet-potato field the larva? started on the south side and, after stripping the first four or five rows, moved over to the next rows and eventually infested the entire Fig. 10. — The semitropieal army worm (Prodenia eriflania) : Field of late Irish potatoes showing vines entirely stripped by larvse ; Orlando, Fla., July 6, 1907. (Original.) field. A Mr. Porter, near the County Home, reported 5 acres stripped in three days after the larvse were noticed at work, these having started at one side of the field and swept it clean. The larva? of a third generation were observed at Mr. Cheney's place at this time; most of them, however, had already gone into the earth to transform. August 3, adults that had pupated about July 25 began to emerge. Thus the pupal period occupied about nine days. At this time a number of young larvae Avere noted feeding upon amaranth, wild Solanum, and castor-oil plants. When disturbed they dropped and hung by threads. THE SEMTTROPICAL ABMY WORM. 61 By the first of September Mr. Cheney's patch of sweet potatoes was entirely free from this insect, evidently owing largely to parasites and to the spraying with arsenate of lead. August 30, 1907. Mr. Wm Donnell. St Augustine, Fla., reported thai a cutworm, which he identified as this species, had been very destructive in that region, being especially abundant on beets, and Pig. 11.— The semltropical army worm (Prod en ia eridania) : Larvae eating bark of "care- less weed;" also nymph of Podisus macuHventria, predaceons on the larre. (Origi- nal.) later affecting cabbage, carrots (by eating the tops), ami some other plants, it- operations being most noticeable at night. .Mr. E. L. Worsham, while employed by this Bureau, noticed this species on the west coast, near the Manatee River, in Florida, and reported it working quite extensively in that region in August On November 23, 1907. an egg-mass was found on pokeweed at Dade City, Fla., and December "J another was observed, from which 62 SOME INSECTS INJURIOUS TO TRUCK CROPS. the larvae hatched December 4. These molted between December 10 and 13, while being transported to Orlando, but soon died, as frost killed off the food plants. July 25, 1908, Mr. H. H. Dickson asked for a remedy to apply against the larvae on sweet potatoes at the Orlando Truck Farm. Egg-masses received May 24, 1907, hatched at that time and the larvae entered the earth in the rearing cage June 19. In dry sand the pupae were found at a considerable depth, but in moist sand they were found barely under the surface. July 8 larvae in the rearing-cage were almost full grown. Larvae hatching from egg-masses, and others a few days old, were also found in abundance on sweet-potato plants. As soon as hatched they separate, feeding on the leaf on which the egg-mass was laid, perforating the underside full of minute holes, and leaving only the upper epidermis, which turns brown. On growing larger they. sep- arate, as in the case of most caterpillars, except those of peculiarly gregarious habit, and soon become widely scattered. Even when abundant it is common to see eight or a dozen on the underside of a single leaf, and frequently as many as an hundred. Occasionally a nearly full-grown larva feeds on the upper side of a leaf. In many cases large larvae were found hiding during the day at the bottom of furrows. June 15, 1908, the larvae of this insect were found to be very abund- ant at Orlando, Fla., in one part of the town feeding on pokeweed, and in another on amaranth. EARLY RECORDS. Among the records of the Bureau of Entomology is one of May 22, 1887, when larvae and pupae were received from Mr. E. A. Schwarz with report that the species was very injurious to the eggplant at Cocoanut Grove, Fla. In September, 1905, Mr. F. C. Pratt sent to the Bureau a large colony of the larvae found feeding on pokeweed at Dallas, Tex., the moths from which began to issue September 26. LIFE-CYCLE PERIODS AND GENERATIONS. Larvae mailed from Orlando, Fla., July 3, arrived at Washington, D. C, July 5 and began to enter the earth for pupation the following clay. On the 16th two had transformed to pupae, on the day follow- ing three more, and the remainder transformed within a week. This experiment shows a pupal period of about 9 days, allowing 1 day for the larvae in the earth before pupating. The weather was quite hot. In a cooler temperature in August the pupal period required 11 to 13 days. The moths hatched from different lots were separated and the egg- period observed. In one case this lasted from August 8 to 12, or THE SEMITROPICAL ARMY WORM. 63 4 days, and in another case from July 18 to 22. or 4 days. In the first instance the temperature averaged between 70° and 80° F. and in the second from 80° to 88° F. Evidently this is the maximum period. As regards the duration of the entire life cycle, it was noticed that eggs deposited July 3 produced caterpillars on the 0th. or in 6 day-. These penetrated the earth, being full-grown, on the 2Gth. making the entire life period of the larva? 17 days. They began to issue as moths August 5. This gives a total period for the life cycle of 31 days for extremely hot weather. In an ordinary outdoor summer tempera- ture the period would be about 35 days, or 5 week-. Our rearing records are not quite as accurate as could be desired, owing to unfortunate conditions at the insectary and to three changes in the office force during the time when the insect was under observa- tion. There were, however, positively four generations here, and about the same number was observed at Orlando. There is also the possibility of an earlier fifth generation in nature. The exact periods for the appearance of these should be recorded in the field. NATURAL ENEMIES. The unusual abundance of this species at Orlando. Fla.. during the season of 1907 afforded a most excellent opportunity for the study of its insect natural enemies. These came under observation as early as May and were still abroad as late as August, appearing to increase somewhat as the season advanced. PARASITES. The parasitic species observed were seven in number; the pre- daceous enemies, six. Ophion t it i/r/ Pack. (?) — Issued July 17-August 1. Limnerium sp. — Issued May 25-30. Meteorus sp. — Issued July 11-August 2. Chelonus sp. — Issued July 6, 1908. Spilochalcis spp. — The Meteorus was attacked by two species of secondarv parasites of the family Chalcididae. These issued August 2 from the peculiar brown cocoons of the Meteorus. Winthemia quadripustulata Fab., a moderate-sized tachina fly. i- a No a parasite on the larva of this species. Adults issued Augi but did not appear abundant. Of a lot of larvae taken at random from different portions of a field, upward of 50 per cent bore tachina- fly eggs. Evidently a large percentage fail to hatch.1 "A small fly was also observed feeding on the pupffi. It is AphiochaUl nitjri- cepa Loew, one of the Phoriche, which comprises species of scavenging habits and not parasitic. 64 SOME INSECTS INJURIOUS TO TRUCK CROPS. PREDACEOUS ENEMIES. Calosoma sayi Dej. — The larvae of the carabid beetle Calosoma sayi were observed in considerable numbers and were reared to adults. They were first noticed July 6, when they were quite abundant in the furrows between rows of sweet potato. They were found concealed by the vines, feeding on the larvae of the Prodenia, and after sucking out the juices of one larva they immediately attacked another. The adults issued in our rearing cages August 11. Polistes annularis L. — The large brown wasp Polistes annularis was observed July 2, flying quite commonly in sweet-potato fields. One was watched which alighted on a leaf and began searching for prey, after the custom of such wasps. The search was continued from plant to plant and from leaf to leaf until a Prodenia larva was located, when it was at once seized behind the head and chewed into a shapeless mass. Other wasps of this species were also seen on fence posts dragging Prodenia larvae about with them. It is interesting to note that Mr. F. F. Crevecoeur, Onaga, Kans., reports having seen this wasp being carried away by the asilid robber-fly, Deromyia ternata Loew. Stiretrus anchorago Fab., var. diana Fab. — The bluc-and-red and the uniformly blue forms of the soldier-bug Stiretrus anchorago, which are common in Florida, were observed in numbers attacking the Prodenia larvae in July. Podisus maculiventris Say. — During July the spined soldier-bug was seen preying upon the Prodenia larvae. (See fig. 11.) In one instance 18 nymphs were counted on a single amaranth plant infested by the cutworm. The length of the life cycle of this species from hatching (not from egg-laying) was determined to be 16 days in hot July weather. Apateticus (Eupodisus) mucronatus Uhl. — July 17, and again in December, 1907, this pentatomid bug was observed preying on the larva of this species of Prodenia at Orlando, Fla. It is considered a rare species and this is probably the first observation which has been made on its habits. Owing to the obscurity of the host insect in the past, no records can be found of any of these parasites or of other natural enemies which affect it, but in Smith and Abbot's work mention is made of a species of " Ichneumon " which attacks the larva (see p. 58). Pontia rapce L. — July 22, 1907, the young larvae of the imported cabbage worm, which had hatched out on cabbage used as food for Prodenia eridania Cram, in our rearing cages at Washington, were THE SEMITROPICAL ARMY WORM. 65 observed feeding on the eggs of the latter.0 The cabbage worms were between one-quarter and three-eighths of an inch in length at this time. A FUNGOUS DISEASE. Empusa sp. — September 8, 1907, a few Prodenia caterpillars, which were found dying of a fungous disease in our rearing cages, were referred to the Bureau of Plant Industry for identification of the fungus. Mrs. F. \V. Patterson stated that it was a species of Empusa. METHODS OF CONTROL. The arsenical poisons are effective against this army worm under ordinary conditions. Experiments performed at Orlando, Fla., how- ever, brought out the fact that Paris green, on account of the frequent rains which occur at the height of the principal outbreaks in the infested regions of Florida, such as Orlando, is almost ineffective and it is therefore necessary to use arsenate of lead. Owing to the greater adhesiveness of the latter it remains on the plants when the former is washed off. Paris green, arsenate of lead, and a special preparation which may be called adhesive copper arsenite, were tested, the last by request of its inventor. It was used in experiments Xos. 8. 10, and 11. A barrel sprayer, fitted with Vermorel nozzle, was used for a number of these experiments, but for most of them a knapsack sprayer of fine quality was employed. Sweet potatoes were sprayed in every case except in experiment Xo. 5, where collards were also sprayed, and the work was usually begun between 8 and 10 a. m. in bright sunlight. Spraying experiments commenced July 12 and were continued until August 7. Experiment Xo. 1. — July 12. infested plants were sprayed with a solution of Paris green. 5 ounces, and freshly slaked lime. 5 ounces, in 50 gallons of water. The spraying was done in the morning and rain fell before noon. The next day when the field was examined the larvae were found uninjured and practically no poison remained on the leaves. The experiment was therefore a failure. Experiment Xo. 2. — July 12, Paris green, 8 ounces, and freshly slaked lime, 1 pound to 50 gallons of water, were sprayed the same day and with the same results. Experiment No, 3. — July 17, Paris green was sprayed as in Xo. 2. Again rain fell hard and steadily before noon, with the same results as in experiments 1 and 2. a This would seem to furnish at least one reason why this Important insert has heen ahle to supplant its American cousins such as Pomtia nai>i L.. /'. pro- todicc Bdv. & Lec., and /'. monuste L., all of which feed on erucifers and are called cabbage huttertiies or M worms. *' 66 SOME INSECTS INJURIOUS TO TRUCK CROPS. Experiment No. 4- — Arsenate of lead, 2 pounds to 50 gallons of water, was used. Kain fell as before, resulting in partial failure of the experiment, the poison being washed off before it had time to dry thoroughly. Experiment No. 5. — July 20, arsenate of lead was used as in experi- ment No. 4. Collards were also sprayed. Rain did not ensue for at least six hours, giving the spray time to dry on well in the warm sun. The following day it rained hard for several hours, but the next day the spray was found to be as thick on the sweet potatoes as when first put on, in spite of two partially rainy days. The poison was nearly as thick on the collards. An examination of the infested plants two days after spraying showed that only 25 per cent of the caterpil- lars were killed, but July 23, a day later, few large larvae remained on the plants, showing that as soon as they have eaten sufficient poison they are killed. July 29, when the rows sprayed with arsenate of lead were again examined, they were found in much better condition than the check or unsprayed rows, few larvae being seen feeding, while dead ones were plentiful. Experiments Nos. 6 and 7. — July 20, a sweet-potato patch was sprayed with Paris green, 8 ounces to 50 gallons of water. As in the case of experiment 5, no rain fell for about six hours ; therefore the poison dried on well, as previously. The following day it rained hard for several hours, with the result that by July 22 the poison was all washed off and only a few dead larvae were found. All of the Paris green experiments were failures, since the rain washed the poison off either before it could dry or after it was well dried on the plant. Experiment No. 8. — July 23, the adhesive copper arsenite (com- bined with dextrine and glucose) was used at the rate of 1 pound to 100 gallons of water and applied as in previous experiments. The following day no results were observed, but the foliage was not burned. At the end of a week no good was accomplished and the ex- periment was pronounced a failure. Experiment No. 9. — July 25, plants were again sprayed with ar- senate of lead, 2 pounds to 50 gallons of water, the conditions being as in experiment No. 5. Rain at 12.45 p. m. washed off the poison, consequently the spraying was a failure. Experiment No. 10. — July 25, plants were sprayed with the copper arsenite mixture ; 10 ounces to 50 gallons of water were applied as in experiment No. 8, an equal quantity of lime having been added. The spray did not show well on the foliage and was invisible when dry. It does not remain in suspension as well as Paris green and much residue remains in the tank. July 28, a few dead larvae were found THE SEMITBOPICAL ARMY WORM. 67 on the vines and only a few live ones, buf the same condition- were observed on the check row.-. The experiment was an absolute failure. Experiment No. 11. — July 29, plants were sprayed with copper arsenite mixture at the rate of 15 ounces to 50 gallons of water. In this case \\ ounce- of copper arsenite and 1 quart of thick lime v used with 5 gallons of water. Two day- later the -pray showed better than in experiment No. 10 because of an abundance of lime and was very finely and evenly applied to the leaves. Four larva- were dead on a few plant- examined against 32 living Prodenia and 3 living sweet-potato sphinx-moth larvae (Phlegethontius convolvnli L.). August 0. this -pray >till remained on the foliage, seeming to adhere well, but the experiment was a failure in killing larvae. Experiment Xo. 12. — July 20. plants were sprayed with arsenate of lead. 3 pounds to .50 gallons of water, applied as in previous experi- ments with lead arsenate. There was no rain for 24 hours. On a few plants examined three days later 41 dead larvae were found and 49 living, an observed death rate of less than 50 per cent. It should be pointed out at this time, however, that it is difficult to find dead larvae, as they sometimes dry up or crawl away. August 2. the vines were almost free from larva?. The experiment was pronounced very successful. Experiment Xo. 13. — July 30. arsenate of lead. 2 pounds to 50 gal- lons of water, was used without ensuing rain. In some row- exam- ined August 1 about 20 per cent of the larva1 were dead ; in others 48 per cent, 54 per cent, and 01 per cent were killed in two days. August 5, these rows appeared entirely free from larva unless closely in- spected, when only 5 or 6 could be found to a row. These might have crawled from unsprayed weeds or other plant-. Ex peri an nt X<>. 14. — July 30. arsenate of lead, 3 pounds to 50 gal- lons of water, was used. Three days later 84 per cent of the larva under observation were destroyed, the rows being quite clean. In both of these experiments. 13 and 14. many dead larva were found in rows not -prayed, as many as rive rows away from the sprayed one-. Experiment Xo. Id. — August 7. arsenate of lead. 2 pounds to 50 gallons of water, was sprayed by a laborer, under supervision. It rained at 1 p. m.. but the spray remained on the leave- in large amounts and. for having been applied by an inexperienced hand, was well distributed. In this experiment, for some reason, the first four row- sprayed at one filling of the tank produced quite a number of burned leave-. This was attributed to a possible mistake in weigh- ing out the chemicals. It did not. however, permanently injure the plants. Caterpillar- in the la-t I experiments, supposedly of the third gen- eration, were very small, not over one- fourth or one-third of an inch in length. As a consequence they were quickly killed, large numbers DO SOME INSECTS INJURIOUS TO TRUCK CROPS. of them being found dead soon after spraying. Forty-three dead larvae were found in a furrow beside one plant which contained 29 dead larvae. In another place 112 dead larvae were counted in 3 feet of furrow. RESUME OF EXPERIMENTS, AND CONCLUSIONS. Experiments 1, 2, 3, 6, and 7, in which Paris green was used at the rate of 5 to 8 ounces in 50 gallons of water, were failures because in each case the rain which followed the application washed off the poison. Experiments 4 and 9, in which arsenate of lead was used at the rate of 2 pounds to 50 gallons of water, were also failures for the same reason. Experiments 8, 10, and 11, in which copper arsenite was used at a rate of from 10 ounces to 1 pound in 50 gallons of water, failed, not because of burning the foliage, as was feared, but because the in- sects were not killed. Experiments 5, 12, 13, 14, and 15, in which arsenate of lead was the insecticide employed at the rate of 2 to 3 pounds in 50 gallons of water, were successful in each case. The results of this series of fifteen experiments show conclusively the superiority of a spray of arsenate of lead to one of Paris green when applied under suitable conditions. It is in every way more effective and more satisfactory than the latter, as Paris green is so likely to be washed away by the frequent rains of the wet season of Florida. These remarks apply practically to all cutworms, cater- pillars, and other larvae which devour truck and related crops in central Florida or similar regions. ADHESIVE COPPER ARSENITE MIXTURE. The preparation of copper arsenite used in the experiments that have just been reported was stated by its inventor to be free from soluble arsenious acid and to possess the adhesive properties found in no other adhesive insecticide. It was stated to be composed of 36 per cent dextrin and 4 per cent gum and was prepared to be used in conjunction with lime in the proportion of 1 part by weight to from 4 to 6 parts of lime — either dry or in solution, according to the foliage to be tested. The inventor also expressed his confidence that this insecticide would prove a most economical one for general garden and other use, as the loss by wind and rain would be reduced at least 50 per cent and the first cost of the article would be about half that of Paris green or arsenate of lead. Samples of this mixture were submitted to Mr. J. K. Haywood, Chief of the Miscellaneous Laboratory, Bureau of Chemistry, who furnished the following analysis, August 7, 1907 : THE SEMITROPTCAL ARMY WORM. 69 Analysis of 'r~>~>i Misc. Per cent. Moisture 4. 85 Total arsenious oxid 40.42 Total copper oxid 24.87 Gum and dextrin (approximate) 20. 00 Acetic acid and other undetermined 0.80 Total 100. 00 Soluble arsenious oxid 11.36 (10 day water ext. method.) From the above analysis the sample evidently consists of about 20 per cent gum and dextrin and 80 per cent Paris green. The amount of soluble arsenic is very high and would undoubtedly give rise to serious trouble. SUMMARY. The semitropical army worm is a smooth or hairless noctuid caterpillar, Prodenia erldania Cram. It feeds normally on weeds, such as the pokeweed and spiny amaranth or " careless weed " of the South, and is confined to semitropical America as a pest. When it becomes unduly abundant it attacks the foliage and, in some cases, the stems and fruits of all forms of garden truck growing in its habitat, the list of known food plants including tomato, potato, sweet potato, eggplant, pepper, okra, collards, and cowpeas. In its habits it is similar to the cutworms, having also the climbing habit, and when extremely abundant it migrates in armies like the common army worm, whence the name. Experiments show that the egg period may be passed in a min- imum of 4 days, the larval period in IT days, and that the entire life cycle, in an outdoor summer temperature, would be about 35 days or 5 weeks; also, that there are four generations and possibly five pro- duced in a year, the insect breeding practically continuously during the warm season. In ordinary years the species is largely controlled by natural enemies, of which seven are parasitic and six predaceous. A series of fifteen experiments was conducted against this species in Florida during 1907, which shows conclusively that a spray of arsenate of lead is the best remedy, being much superior to Paris green when applied under local conditions. It is in every way more effective, chiefly becau-e le^s likely to be washed away by the frequent rains of the wet season in that region. It is best applied at the rate of 2 or 3 pounds in 50 gallons of water, and applications must be renewed when the insects again become numerous, as the latter are apt to spread from unsprayed plants. 70 SOME INSECTS INJURIOUS TO TRUCK CROPS. BIBLIOGRAPHICAL LIST. 1. Cramer, Pierre. — Papillons exotique, Vols. Ill & IV, p. 133, pi. 358, fig. E. & F. (2), 1782. Description and figures of both varieties of moths. 2. Smith, J. E. and Abbot, M. J. — Lepidopterous insects of Georgia, Vol. II, p. 193, pi. 97, 1797. Described as Plialcena pJiytolaccw with brief account of habits. Figures of moth and larva. 3. Grote, A. R.— Bui. Buff. Soc. Nat. Sci., Vol. II, p. 28, 1873. Listed as Xylomiges Phytolacca? (S. & A.) and recorded from California and Atlantic District. 4. Morrison, H. K.— Proc. Acad. Nat. Sci. Phila., p. 62, 1875. Technical description as Actinotia derupta n. sp., from Texas, September 21. Briefly compared with Phytolacca' S. & A. 5. Grote, A. R.— Can. Ent, Vol. XI, pp. 205, 206, 1879. Received from Texas and referred to Prodenia phytolacece ; characters, etc. No excuse for Morrison's Actinotia derupta. 6. Hulst, G. D.— Bui. Brooklyn Ent. Soc, Vol. Ill, p. 77; Vol. IV, p. 7, pi. 1, fig. 9, 1881. Described as Leucania nigrofascia from one specimen taken by Koebele at Tallahassee, Fla. 7. Smith, J. B. — Catalogue Noctuidae Boreal America, p. 169, 1893. Bibliography ; synonymy and distribution. 8. [Chittenden, F. H.]— Yearbook U. S. Dept. Agr., 1907 (1908), p. 545. Brief unsigned notice of injury to truck crops in Florida. In Smith's catalogue of Noctuida?,7 fifteen references are given to this species, but as only a few of these are of interest in connection with the present account, the reader is referred to that list. The more important references are listed above. V. S. D. A.. B. B. Bui. 86, Part VI. 8, 1909. SOME INSECTS INJURIOUS TO TRUCK CROPS. THE HOP FLEA-BEETLE. (Psylliodes punctulata Melsh.) By F. H. Chittenden, Sc. D., In Charge of Truck Crop and Special Insect Investigations. INTRODUCTORY. A minute, metallic blackish flea-beetle. Psylliodes punctulata Melsh.. known by different local names, has been reported in recent year- as doing very extensive injury to the hop plant and considerable injury to sugar beet. Since 1004 it has been reported in numbers on sugar beets grown in several localities in Idaho. Utah, and Colorado. In the Northwest, and particularly in British Columbia, it does serious damage in hopyards, and has been especially destructive since 1903. During the past three years, indeed, this species has become unusually abundant, with the result that in the Chilliwack and Agassiz Valley hop-growing regions of British Columbia it has accomplished damage which has been estimated by Mr. H. J. Quayle as about SO per cent of the crop. Mr. Theo. Eder informs the writer that this means a cash loss of not less than $1*25.000 in that district. The species during that period has been the subject of considerable correspondence be- tween this Department and persons practically interested in the grow- ing of hops in the affected region. The insect has received the name of rhubarb fiea-beetle. from it- common occurrence, especially in the East, on rhubarb. In the Wot it is called the hop flea-beetle, or " hop flea." or simply " Ilea." and in literature it has received mention as the punctulated and the small- punctured flea-beetle. While the species is not known to be of the highest importance a- a sugar-beet pest, the probabilities are that it may become so. and at the present time it is probably the most important hop pesi in the entire world. The incorporation of some new matter, gained from con- versation with Mr. Theo. Eder and by correspondence with Mr. II. J. "18°— Bull. 66— 10 6 71 72 SOME INSECTS INJURIOUS TO TRUCK CROPS. Quayle, has added much to the value of the present paper. Although the species is much more serious as a pest in British Columbia than in the United States, it is likely to become important throughout the Pacific coast region where hops are grown. Mr. Eder repre- sents the E. Clemens Horst Company, which owns extensive hop- yards in British Columbia, and has already expended considerable sums in investigation and experiments. The hop flea -beetle is now abundant practically on the border line between British Columbia and the State of "Washington, and threatens our own industries. It is, therefore, advisable that everything possible concerning it should be made public before its appearance in the spring, although there are several points in its life history still to be worked up. DESCRIPTIVE. The hop flea-beetle (fig. 12) is a member of the tribe Halticini, family Chrysomelidse, and resembles other flea-beetles in its strongly Fig. 12. — The hop flea-beetle (Psylliodcs punctulata) : a, Larva; b, lower surface of head of same ; c, upper surface of anal segments of same ; d, beetle, a, d, Much enlarged ; 6, c, more enlarged, (a—e, After Carpenter; d, original.) developed hind thighs. It is of oval form, with a greenish tinge, brassy blackish, and punctulate or finely punctured, whence its spe- cific name. The femora, tarsi, and basal joints of the antennae are pale yellowish. The punctulations of the thorax are particularly fine and appear as if made with the point of a very fine needle. The punctures of the elytral stria? are closely placed, almost crenate. The beetle is only about one-tenth of an inch (2mm) in length and less than lmm in width. The male is particularly distinctive, hav- ing the first joint of the anterior tarsi broadly dilated and the last THE HOP FLEA-BEETLE. 73 ventral segment sinuate each side, while the middle of the disk near the apex has a semioval depression.0 The species was first described in 1847.1 b DISTRIBUTION. The hop flea-beetle is a native American species, quite distinct from any species found on hops in England or on the Continent. The collection of the U. S. National Museum and the published records and specimens before the writer show the species to be gen- erally distributed in the northern United States and southern Canada. from the Atlantic to the Pacific. It does not appear to occur south of Nebraska. The list of known localities follows : Cambridge. Mass. : Dundee. Ithaca. Long Island. Staten Island, and New York. X. Y. : New Jersey, generally distributed (Smith) ; Pittsburg. Pa.: Marshall Hall and Cabin John. Md. : Marquette. Detroit. Grand Ledge, and Byron. [Mich. ; University, N. Dak. : Lincoln and Omaha. Nebr. : Fair- field. Wyo. ; Denver. Longmont, Grand Junction. Delta. Montrose, Paonia. and Ft. Collins. Colo.; Logan. Garland. Lehi. Salt Lake, and Park City. Utah; Elko. Nev. : Blackfoot, Idaho; San Francisco. Mar- tinez. Monterey, Huntington Beach, Pasadena, and Chico. Cal. ; Tenino. Wash.; Astoria and Marion, Oreg. : Agassiz, Sardis. and Vancouver, British Columbia: Northwest Territory; Manitoba; and " Assiniboia " (now Saskatchewan). RECENT INJURIES. September 16, 1903. the late Dr. James Fletcher first reported this species injuring hops in British Columbia. During 190G Mr. Theo. Eder wrote from San Francisco, Cal., under date of April 9, that hop growers were troubled considerably in some sections by ;i hop fleas," or flea -beetles. May 29, specimens were received from Perkins, near Sacramento, Cal.. which proved to be the species under consideration. August 13, Mr. Hugh F. Fox. Xew York. X. Y., sent .specimens and transmitted a report from Mr. Geo. Heggie, manager of a large hopyard, the Stepney ranch, owned by Sir Arthur Stepney, at Enderby. B. C, where this pest was very injurious. Mr. Heggie wrote as follows: We have been sorely troubled this year in our hopyard with the "hop flea- beetle," which attacks the young vino and leaf as Boon as they appear above the ground, and eats out large holes in the leaf, resulting in the plant being a In the very closely related P8. COtwexior Lee. the last ventral segment <>f the male is convex and not impressed. The latter species is. moreover, larger, broader, and more convex, and the elytra! stria' are not Impressed. 6 The numbers in superior type refer to corresponding numbers in the ap- pended bibliography, p. in. 74 SOME INSECTS INJURIOUS TO TRUCK CROPS. impoverished in vitality and the growth thereby seriously retarded. We were troubled with them last year [1905], but not to the same extent, and had them till after hop picking. In the middle of July they were so numerous that the ground was fairly alive with them. They go into the ground in the evening and come out again in the morning, and there has been no spray found to have any effect without killing the plant. Substantially the same form of injury was reported during the same year at Agassiz, B. C, by Mr. John Wilson in a letter to Doctor Fletcher. Writing September 7, 1906, Doctor Fletcher stated that this species had been enormously destructive in British Columbia, one correspondent reporting the loss of many thousands of dollars. He estimated his crop as possibly TO bales, whereas he should have had 250. Writing of this species, January 30, 1907, Dr. E. D. Ball, while working in cooperation with the writer, stated that it was by far the most injurious species on sugar beet in Utah. It was found every- where and was apparently the most common species in early spring. It was observed hibernating around the edges of fields, in patches of dead mustard, along ditch banks, and in similar places. Where ditches were covered with patches of roses these seemed to furnish a favorite retreat. These clumps grew to a height of 2 or 3 feet and were very dense, and from them one could see the injury to the beets radiating in every direction, the affected area growing wider and wider as time went on. In early spring this species fed on almost anything that came to hand, but its injury to beets was practically all done at the time the plants were first appearing through the ground or within a few days thereafter. Cases were observed where the rows of young plants could be seen the entire length of the field one clay, and two clays later scarcely a beet plant could be found, the beetles having eaten the tender stem, causing the tops to fall off and the beets to die. Frequently they attacked beets just as the latter were pushing through the ground. Hundreds of acres had been destroyed in this way, injury varying greatly in different years and in different localities. Great damage was done near Logan, Utah, where the hedge mus- tard was overrunning the fields. At Lewiston, Utah, at the northern end of the same valley, injury was also severe, although there was little of the common black mustard. The destruction of a crop by this species does not necessarily entail a complete loss, as the growers replant. The late plants, however, are not, as a rule, as good as the earlier ones, and the weeds get such a start that the land is hard to cultivate. After the beets had reached a leaf diameter of 3 or 4 inches no material injury was noticed, although the beetles continued to appear in the fields throughout the season. Beetles were observed July 20, 1906, at Cache Junction, THE HOP FLEA-BEETLE. 75 Utah, enormously abundant on a form of hedge mustard along the railroad tracks, feeding on the half-grown seeds. Single plants were seen on which a double handful of beetles could be taken at one stroke of the net. In a letter dated July 20, 1908, the E. Clemens Horst Company, Perkins, Cal., wrote of extensive injur}' by this species, and as this letter contains much of interest it is transcribed herewith. The writer is greatly indebted to the same company for the excellent pho- tographs from which the ten half-tones illustrating this article are taken. We are extensive growers of hops on the Pacific Slope, California and Oregon, and also have about 600 acres of hops in two ranches in British Columbia. For the past three years we have been very much molested in British Columbia by a variety of flea-beetle that seems to take an esi>ecial liking to hop foliage and eats the young, tender shoots as they come out of the ground, and also the developed and partly developed leaves of the vines after the same are above ground. There are two other growers in the same section that were bothered one or two years previous to ourselves, and as they had some foreign varieties of hops we at first supposed the insects had been imported from England in the roots. Since, however, we have found that the same insect has been in the neighborhood in very small numbers for quite a long term of years. Our crops in British Columbia suffered quite a bit last season, but this year are very nearly a total failure. From the one place, Chilliwack. P>. C, containing 278 acres, we do not expect to reap a harvest of more than GOO bales, whereas we should have from 2,500 to 3,000 bales. From the other place, Agassiz, R. C, we do not expect over 250 bales of hops, whereas we should have 2.250 to 2.700 bales. This will give you some idea of the inroads made by the insect and the resultant loss to persons engaged in hop growing when their yards are attacked by these pests. Of course we readily understand that it would be somewhat out of the ordinary for your Department to attack this problem inasmuch as it is out of the United States, but inasmuch as the pests are now so numerous within about 20 miles of the United States boundary and only a short distance from the Washington State hopyards we believe it is well worth your considera- tion. Just imagine for a moment the loss that would fall to the numerous growers of hops in the States of Washington, Oregon, or California, if this pest should not be held in check, and would migrate to these sections. We have definite knowledge of their already having spread as far as Sumaa Junction, which is on the boundary line between the United States and Canada, where they are attacking cabbage, potato, beets, and other root crops, though the damage done here is not nearly as bad as in the hop fields. * * * A badly damaged hopyard is shown in figure 13. During 1908 injury from the hop flea-beetle was reported by Mr. W. W. Stockborger, of the Bureau of Plant Industry of this Depart- ment, lie mentioned the cases already cited and one reported by Mr. Robert Maitland, of Agassiz, B. C. the latter stating that the ravages of this insect would almost destroy the prospect for a crop during the season. Mr. John Wilson, Agassiz. B. C., who complained 76 SOME INSECTS INJURIOUS TO TRUCK CROPS. of this species in earlier years, reported, under date of July 11, as follows : The flea-beetles have been so numerous that they have stripped every portion of the yard this season. I have noticed these last three days that they are all disappearing, but they all disappeared last season about this time and a second brood came about the middle of July. This " second brood " was probably merely the first-developed gen- eration of the year. This species has also come under the observation of various other collectors and observers. During 190G Mr. Frederick Maskew, while working under the writer's direction in southern California, took it generally in many beet fields. Mr. E. G. Titus, while cooperating Fig. 13. — View of hopyard, showing how completely the hop flea-beetle keeps down the vines. Note occasional vine that grows up. Agassiz, B. C, June 24, 1908. (Original.) with this Bureau in the investigation of sugar-beet pests, found it abundantly, and many of the locality records given under the head- ing " distribution," in California, Utah, Idaho, and other States are from specimens collected by him on sugar beet in 1905, 1907, and 1908. Writing of this species in July, 1908, Mr. I. J. Condit stated that the beetles were then very common in the vicinity of Chino, Cal., on Chenopodium album and C . rurale. METHODS OF ATTACK, FOOD HABITS, AND GENERATIONS. This flea-beetle affects both surfaces of a leaf, gnawing through the skin and devouring the pulp, usually leaving the skin on the op- posite side entire; this later becomes discolored, forming yellowish- THE HOP FLEA-BEETLE. 77 brown freckles as the leaf grows and expands, the skin at this point in time becoming torn and frequently showing holes. When the beetle occurs in moderate numbers the leaves (fig. 14) become riddled, as by fine shot, the punctures being most obvious after the plants ha ve made some growth. In its attack on hops it frequently causes the leaves to look like a mass of network or more or less completely strips the vines of leaves, as shown in figures 15 and 16. As is the case with flea-beetles in general, this species does most harm to young plants. When the beetles occur in considerable numbers they are capable of doing great damage in a comparatively short time, com- pletely devouring the young and tender leaves as fast as they come up. Injury is most noticeable on hops, sugar beet, rhubarb, and some other vegetables. The beetle is a general feeder, the list of its food plants including, among vegetables, rhubarb, beet, cu- cumber, turnip, radish, cabbage, mustard, and po- tato. It feeds also on hops, red and white clover, nettle, dock (Ivimiex), lamb's-quarters (Chenopodium) , pigweed and tumbleweed (Amaranth/us retroflexus and A, yrachins). hedge mustard, and common wild-growing black mustard. The prob- abilities are that, as all of these plants are affected by the adult beetles, a considerable proportion of them serves as food for the larvae. On this head Mr. Quayle has written that the eggs, larvae, and pupae were taken at a depth of from three to six inches from the surface of the ground in hop fields and that the larvae apparently feed on the roots of hop as well as those of other plants growing in the yards. Since it is well known that the beetles occur in other regions where hops do not grow there must be other larval food plants. It would be interesting, and is important, to ascertain exactly what plant, or plants, is the favorite with the larvae. Fig. 14. — Hop leaves, showing work of flea-beetle. (Original.) 78 SOME INSECTS INJURIOUS TO TRUCK CROPS. Fletcher,11 in writing of this species, says that in Canada there are two generations a year, the first appearing in June and the second in August, The generation appearing in August is with little doubt the newly developed first generation, and, reasoning from analogy, i. e., from what we know of related flea-beetles, it is this generation of the beetle that hibernates ; thus the so-called " first generation " is simply that same generation reappear- following spring and ing the early summer As to hibernation, Piper 6 and Doane 8 have recorded that the beetle passes the winter under stones or rubbish, in which respect it resembles practically all other species of American flea-beetles, and that with the first warm days of spring the beetles emerge from their winter quarters and im- mediately commence feeding voraciously upon their various food plants. The following account of the life history and habits of the species in the worst affect- ed locality in British Colum- bia has been kindly furnished by Mr. H. J. Quayle, who has also given an account of reme- dial experiments which sup- plement those previously fur- nished by conversation with Mr. Eder ; indeed, without the information supplied by these two gentlemen this article would be quite incomplete. Before transcribing Mr. Quayle's account it may be well to draw from it, according to the statement of Mr. H. Hulbert, Sardis, B. C, that this species made its first appearance as a hop pest in British Columbia in 1894 and that it has been of great importance for five years, or since about 1903. In regard to Mr. Hulbert's statement that the beetles disappear about June 1 and reappear the last of July, it is obvious that during that period the larvae are maturing, the pupae are formed, and the beetles of the first, or new, generation appear. Fig. 15. — Work of flea-beetle after vines are grown. (Original.) THE HOP FLEA -BEETLE. 79 The following account of the life history and habits of this species as it occurs in British Columbia is taken from Mr. Quayle's manu- scripts: LIFE HISTORY AND HABITS. The adult. — The beetle appears very early in the spring and, according to reports, patiently awaits the coming of its food plant. This early attack of the beetle as the plants are bursting through the ground and before the leaves are fully expanded is one of the things that makes control work difficult Before the hops appear the beetles are known to attack the nettle, and often com- pletely riddle the leaves. They also attack other plants, and have been seen, and evi- dence of their work noticed, on potato, mangel, beet, turnip, dock, lamb's-quarters, pigweed, and red as well as white clover. Xone of these plants is attacked, however, in preference to hops and it is rarely that they are found at this season on anything but hop vines. In one or two cases they were observed in some numbers on potato, at a considerable distance from hop vines. On a small field of hops that was deserted last year on account of this flea-beetle and planted to clover, the leaves of the latter were considerably eaten. The first appearance of the beetles in this section, according to Mr. Hulbert, was fourteen years ago. and they have been attacking his hops for the past five years. The beetles jump very readily when dis- turbed, but fall to the ground, usually not far from the base of the vine. Experiments to determine the power of jumping, which is an important factor in control work, indicate that they may not jump more than a foot in the vertical and about a foot and a half in the horizontal. Feeding occurs almost entirely on the upper surface of the leaves, where they eat out small, nearly round holes about one-eighth of an inch in diameter. This is continued until the leaf is reduced to a network and finally nothing but the main ribs remain. Many of the vines grew to a height of three or four feet, then the foliage was completely stripped off, leaving the dead stalks, which may still be seen in the fields. Many of the vines are thus killed to the ground. Strings were put in place in VM)<, in anticipation of the usual crop, hut were taken down and saved for another year, as the vines that started afterward were too late to make a crop. Cultivation was stopped ami a thousand sheep were Imported from California by the Horsl Company to feed in their yards. The beetles, with their more or less cone-shaped bodies, readily make their way through anything into which they can get their heads, and our expert- Fig. 1G. — Trained hop shoots stripped by flea-beetle. (Original.) 80 SOME INSECTS INJURIOUS TO TRUCK CROPS. mental cages [fig. 17], which were covered with cheese cloth, had to be re- covered with calico. They also make their way through the soil with little difficulty. Experiments to determine this point consisted in burying them at different depths, enclosed in tin cylinders. In two days the beetles appeared through 2, 4, and 6 inches of loose soil, but did not appear from these same depths where the soil was made compact by tamping. The egg. — A few eggs have been taken on the hop roots about 4 inches below the surface. Obviously, these are most difficult to find and can not be detected at all without a magnifier. To more easily obtain the eggs and youngei stages, tin cylinders, 8 inches in diameter and 2 feet high, have been sunk to a depth of 8 inches in the ground, some enclosing hop vines and others in the open field. Large numbers of beetles have been liber- ated in each of these, and they will be taken up with the soil intact in the tins in two, three, and four weeks, and the soil carefully ex- amined for eggs and larvae. Beetles taken in mating, and enclosed in vials witl earth at the bottom, have laid eggs in from eight to ten days. The larva. — Larvae of what the writer believes to be this flea-beetle have been taken from 2 to 4 inches below the surface, both around hop roots and in the spaces between the vines away from any hop roots. While most of the larvae have been taken about hop vines, I think that they are not restricted, in feeding, to the roots of the hop ex- clusively, since some have been taken in spaces be- tween the hop vines and also because of the wide distribution of the beetle, both in the United States and in the valleys of the Chilliwack and Agassiz, away from any hopyards. Search about the roots of the nettle and other plants growing along the borders and roadsides failed to reveal any larvae. The pupa. — We have also taken pupae of what was considered this flea-beetle. Transformation to the adult was, of course, necessary to establish this positively and some of the pupae taken to the laboratory duly transformed. These were taken about the hop roots 3 or 4 inches below the surface. Both larvae and pupae, when sought at the same time, were extremely scarce, and sometimes an hour's search would result in finding nothing. Earlier in the Fig. 17. — Breeding and control cage in place over a hill. (Original.) THE HOP FLEA-BEETLE. 81 year would undoubtedly be a more opportune time for getting the younger stages, but our rearing-cage experiments, starting with the beetles in mating, should give us ample material for the study of the younger stages. The scarcity of the larvae at the time when sought is attributed by the writer to the fact that it was too late for the large numbers of spring and too early for those expected to appear about six weeks later, according to reports of previous years. Those few which were obtained are probably late individuals of the last brood. Two other kinds of larva? are taken commonly in the ground, these being wire- worms and carabid larva?. Many of these are very small, just about the size of our flea-beetle larva?, and the wireworms, when first hatched, are of the same white color, but both of these forms of larva? can be readily distinguished from the flea-beetle larva?. The few pupa? obtained are undoubtedly those of what we consider the flea-beetle. Development. — From all accounts this flea-beetle keeps emerging continuously throughout the season, though there are periods when the beetles occur much more abundantly than at others. Last year Mr. Hulbert stopped using the tarred boards June 1, when practically all of the beetles had disappeared. They did not reappear until the last week in July, when the jarring method was resumed. This year (1908) he continued the use of the tarred boards up to the second week of July, this difference over 1907 being attributed to the cold wet season. According to this, the next lot of beetles may not appear before the last of August of the present year. Beetles have been seen breeding con- tinuously during the past two weeks, though not abundantly, one pair being seen out of seventy-five or one hundred beetles. Beetles are usually present in considerable numbers in the fall, when the hops are mature, and do much direct injury to the product. NOTES ON OTHER SPECIES. A few remarks in regard to the larval habits of our other American and some European species of Psylliodes may be interesting. The writer has several times observed the beetles of the equally well- known PsylJiodes convexior Lee. in numbers on shepherd's purse {Bursa bursa-pastoris) in June near the District of Columbia, and it is probable that this is the larval food plant. Until the publica- tion of Mr. Quayle's article 12 there was no record of any of our four species having been reared; hence, the natural conclusion that they were root-feeders. In Europe no less than forty-nine species of Psylliodes are recognized in a recently published catalogue1 and the habits of those which have been studied indicate a preference for cruciferous plants, although several are attached to widely differ- ent groups of plants. Thus among European species are the hop flea-beetle (Ps. attenuate Koch), the potato flea-beetle [Ps, a/finis Payk.), and a species which is mentioned and figured by Taschen- berg& as the " raps-erdfloh " (Ps. chrysocephala L.). The last is very abundant and has been known for years to attack edible crucif- erous crops. It has been recently treated (1906) by Mr. Geo. a Reitter, Catalogue Coleopterorum Europce, pp. r>7L>-oT4. 1906. bPraktische Insekten-Kunde, l't. 11. p. 903, flg. 1\). Bremen, 18T9l 82 SOME INSECTS INJURIOUS TO TRUCK CROPS. H. Carpenter as a cabbage pest in an article in which the larva is described and illustrated in detail. As to its biology Mr. Carpenter a reaches the conclusion that the female beetle lays her eggs on the underground part of the stem and that the young larva burrows through into the interior and feeds in the central tissue of the stem and taproot until mature. The papal stage lasts about three weeks and is passed in an earthen cell just beneath the surface. The natural larval food plant is evidently a wild crucifer. LOCAL CONDITIONS AND NATURAL INFLUENCES. Inquiry was made of Mr. Eder during his visit to Washington, D. C., in December, 1908, as to the local conditions in the infested area. From what was learned through him it would appear that the insect's occurrence in such great numbers in the hopyards of British Columbia was due to the equable temperature and to the humidity, which keeps the soil practically always sufficiently moist for the oper- ations of the larva? feeding beneath the surface. There can be no doubt, from the writer's observations of our east- ern flea-beetles, that these are largely held in check, especially in regions like the District of Columbia, by the extremely dry heat of midsummer. At the time that the flea-beetles are developing as larvae or undergoing their transformation the ground is nearly baked by the heat during the da}^ and softened only by dews at night. The conditions are very different in British Columbia, and there are, moreover, no other natural causes known which might assist in de- pleting the numbers of the little pest. Among natural agencies only a single species of insect has as yet been discovered preying upon this flea-beetle, a hymenopterous para- site which was known to Fitch - and which he mentions as a " Chal- cidian." It is evidently a species of Perilitus, probably the same species, schwarzii Ashm.(?), as has been encountered by the writer on other species of flea -beetles of the genera Epitrix and Phyllotreta. It develops within the body of the adult or beetle. It is not known if this species occurs also in the Pacific region. If not, it might be possible to introduce it. Fitch's observations and conclusions are interesting, since we have no reason to doubt his theory. Briefly he observed on June 1, 1863, two flea-beetles pairing on a leaf of rhubarb. Presently a parasite alighted near them. It darted upon the back of the female, appear- ing to be inserting its sting in the tip of her body, whereupon she gave a leap and they both disappeared among the foliage. Fitch conjectured that the " chalcidian " was an egg-parasite of the flea- a Journal of Economic Biology, Vol. I, pp. 152-156, PL XI. London, England, November, 1906. THE HOP FLEA-BEETLE. 83 beetle and that the eggs of the latter were so minute that the larval parasite required several of them to nourish and bring it to maturity, as observed of an egg-parasite of the Hessian fly. The parent, watch- ing her opportunity, deposits an egg internally in the ovarie- of the flea-beetle, or in the passage-way therefrom, and the parasite larva, taking up its residence there, consumes the eggs of the flea-beetle, one after another, as they develop, whereby none of them will be extruded until after the parasite has attained its growth. In con- clusion he writes, " Most singular and truly wonderful as such a provision of nature would be, it is the most probable conclusion I am able to arrive at from past observations." METHODS OF CONTROL. Correspondents who have inquired for a direct remedy for use against this species have been advised to experiment with all of the usual flea-beetle remedies. These are, in brief, arsenate of lead, arsenate of lead with resin-fishoil soap, Paris green with and without Bordeaux mixture, Scheele's green, arsenite of lime with soda, dry Paris green with air-slaked lime, Bordeaux mixture alone, and kerosene emulsion. According to Messrs. Eder, Quayle, and others, most of these remedies have been tested more or less completely without being found to be thoroughly effective, owing to the great numbers of the flea-beetles and the rapidity with which the tops of the hop vines grow. All remedies that have been employed have been directed against the beetles only. Unless the hop plants are sprayed nearly every day it is practically impossible to keep them covered with any poison so as to entirely pro- tect them from the ravages of the " fleas." Among other substances tested were tarred boards and sheets, as for leaf hoppers. On account of the employment of cheap labor, chiefly Hindu, mechanical and hand methods were found of some value. Snuff was found effective on a small scale and finely powdered tobacco, such as is now on the market as an insecticide, is to be tested. According to Messrs. Quayle, Eder, and others, the difficulties encountered in the economic treatment of this species are due to two causes: (1) The continual emergence or appearance of the beetles, rendering any method that has yet been employed, such as an arsen- ical or contact spray, or any mechanical means of capture, such as jar- ring, of only temporary value, and (2) the extremely rapid growth of the young hop vines, making frequently repeated applications of a spray or other direct remedy a necessity. AKSKMC U.S. Araenati of laid. Arsenate of lead, applied at the rate of about 1 pound in from 20 to .'»() gallons of water, is advised for use against 84 SOME INSECTS INJURIOUS TO TRUCK CROPS. the hop flea-beetle. Being more adhesive, this mixture, when sprayed upon the plants, sticks more firmly to the leafage than Paris green, and is also very much less likely to produce scorching or burning; indeed, it has been used at T pound to 10 gallons of water on some of the hardier plants, such as potato, without injurious effects. This is, however, not advisable, owing to the extra cost, provided that a weaker solution will accomplish the object. Moreover, scorching is apt to follow its use at this rate on some plants, especially when these are exposed to the direct rays of the sun. The adhesiveness is still further enhanced by the addition of about the same amount by weight of resin-fishoil soap as of the arsenical employed. Mr. Wil- son reported that arsenate of lead, applied at the rate of 4 pounds to 40 pounds of Bordeaux mixture, was inadequate, yet Mr. Quayle re- ports that used at the rate of 5 pounds to 50 gallons it will kill a large number of the beetles, although many take to the new growth that is constantly appearing, or apparently carefully avoid those places on the foliage that have a good coating of poison. The failure of these two arsenicals must be attributed, in large part, to unsuitable spraying apparatus; either of these applications should kill insects on hops, as they have both been found effective, according to Fletcher, against this same beetle on rhubarb in the Northwest Territory and Manitoba. Dry Paris green. — Mr. Thos. Cunningham reported that very little impression was made by an arsenical spray in the region just mentioned, but stated that Paris green dusted on the plants seemed to produce better results. It was applied by means of a Leggett powder gun. Even then some trouble was experienced; in fact, as the arsenical dust or so-called " dust spray " struck the vines the " fleas " hopped to the ground. " In all my experience with insecticides," he says, " I have never seen anything which will approach the fleas in resistant power." Paris green spray. — Paris green, being the most readily obtainable insecticide, was advised by this Bureau when information as to remedies was requested. When properly prepared and applied, according to the directions furnished in Farmers' Bulletin No. 127, this insecticide should have no deleterious effect on the hop or other plants affected. It was advised that other food plants growing in the vicinity, such as rhubarb, turnips, and weeds, should be sprayed with the solution. Regarding its efficiency in hop fields Mr. John Wilson, in a report to the late Doctor Fletcher, stated that when applied at the rate of from 4 to 8 ounces, in combination with Bordeaux mixture, made according to the 1 1 40 formula, or in 40 gallons of water, it was not successful. Bui. 66, Pt. VI, Bureau of Entomology, U. S. Dept. of Agriculture. Plate V. THE HOP FLEA-BEETLE. 85 For use against this species in its occurrence on field and garden crops in Washington State, Messrs. Piper and Doane have advised Paris green. The former states that he obtained excellent results by using Paris green liberally but that it is necessary in the treatment of young plants to apply the remedy as soon as attack by the beetles is noticed. Both the wet and the dry methods are advised, as well as the addition of Bordeaux mixture. Other arsenicals. — Other arsenicals advised in such cases are arsen- ite of lime with soda,a which has the merit of being as effective as Paris green and lime and far cheaper, and Scheele's green, which is similar to Paris green and is employed in the same manner.6 SUMMARY ON THE USE OF ARSENICALS. To sum up the directions for the use of arsenicals, it should be stated that arsenate of lead should take first place because it can be purchased already combined in paste form, and especially because it contains a smaller percentage of free arsenic (60 to 70 per cent), and is therefore less likely to produce scorching or burning; and, moreover, being adhesive, it remains on the plant longer. Paris green, when combined with lime and water, or with Bor- deaux mixture, is almost equally as good as arsenate of lead, and is more readily obtainable in most markets, the ingredients being purchasable practically anywhere. It is quicker in action, but not so adhesive. The number of sprayings will naturally depend upon the locality and seasonal conditions; possibly it may be necessary to spray every few days when the plants are quite young and the beetles are most abundant. Later there should be longer intervals between sprayings. Dry mixtures are as a rule not in the same class with the sprays, as they can not be applied so economically, do not so thoroughly cover or adhere so closely to the leafage, and are more apt to cause burning to delicate foliage. Dry Paris green mixed with air-slaked lime in the proportion of about 1 part of Paris green to 10 or "20 of lime is sometimes used, but is less effective, and frequently much of the material is wasted in applying it. The spraying apparatus used in the hopvards of British Columbia is shown in Plate V and figure 18, the second illustration showing a crew spraying hops through the rows. CONTACT SPRAYS. Among the contact sprays tried during 1008 were whale-oil soap. 1 pound of soap to 10 gallons of water; kerosene emulsion, ] pound " Prepared in accordance with instructions in Farmers' Bulletin No. in:;. v. 37. 6 Discussed in the publication quoted, as also in Farmers' Bulletin No. 127. 86 SOME INSECTS INJURIOUS TO TRUCK CROPS. soap and 1 gallon of kerosene to 25 gallons of water; resin, 1 pound to 16 gallons of water ; and black leaf tobacco extract, 1 gallon to 65 gallons of water. Of these Mr. Quayle says that the last seemed most effective, with kerosene emulsion next, and that none of these sprays in the given proportion injured the foliage at all. It is entirely possible to kill most of the beetles well bit by the spray, but many escape between clods in the soil or are protected by the vine or are con- cealed in tbe growing tip. The percentage killed, however, will be satisfactory, but this [treatment] must be repeated so often that the operation becomes laborious and costly. While kerosene emulsion and whale-oil soap are practically never advised as standard remedies for mandibulate or chewing insects, Fig. 18. — A crew spraying hops in British Columbia. (Original.) such as this flea-beetle, both are employed in the infested terri- tory against the hop aphis, or " louse," and therefore the hop grower is familiar with their preparation and use. It has been ascertained that when these are used against the hop aphis the flea-beetles coming into contact with the emulsion are killed. The probabilities are that kerosene emulsion properly prepared and applied in the affected regions will be considerably less expensive than a tobacco extract, and it is possible to make a tobacco extract which would be comparatively cheap. In recent experiments made under the writer's direction at Norfolk, Va., whale-oil soap, used at the rate of about 1 pound to 10 gallons of water, employed against aphides, has proved quite as ef- fective and as economical as kerosene emulsion, considering the fact THE HOP FLEA-BEETLE. 87 that unskilled laborers are likely to make imperfect emulsions and waste the material in applying it. With competent help, and other things being equal, kerosene-soap emulsion should be the more eco- nomical spray. It would be well to continue the use of kerosene emul- sion at varying rates, including the rate that has been already used and up to 1 pound of soap and 1 gallon of kerosene emulsion to 30 gallons of water. It is possible that if the emulsion were diluted with 10 gallons of water still better results might be obtained, but if labor is cheap the weaker solution, other things being equal, should prove to be the more economical preparation. BORDEAUX MIXTURE. Bordeaux mixture, as has been known for years and frequently demonstrated, is a powerful deterrent against flea-beetles and other leaf-beetles, and its use should be continued. Since, as appears to be demonstrated by the observations of Mr. Quayle, this flea-beetle is quite discriminating in taste, it would be well to apply Bordeaux mixture over a considerable surface and use Paris green or arsenate of lead for the remainder of a field, i. e., to spray the majority of the plants in such manner that those which reject the Bordeaux mixture on treated plants would resort to those sprayed with Paris green or arsenate of lead. It should be determined which of these two insecti- cides has the greater deterrent effect against flea-beetles. MECHANICAL AND CULTURAL METHODS. Trap crops. — The great fondness displayed by this species for rhubarb suggests the use of the latter between rows, e. g., in the vicin- ity of woods, as an attraction or lure for the beetles, it being believed that the beetles will concentrate on these plants and thus give the crops an opportunity to grow to a sufficient height and strength to be able to resist the ravages of the pest. Since certain cruciferous crops are also attacked, such as turnips, it is further suggested that these and other varieties like swedes and rutabagas, rape, and mustard be employed. In the mild climate of the infested region all of these can be grown during the winter, and it seems probable that kale will be found equally effective. Beets, especially mangels, are grown in the affected region and tests should be made with these a- trap crops, as also with sugar beet in regions where this crop can be grown profitably. Rolling the fields. — One of the remedies attempted against this flea- beetle in its occurrence in beet fields, as reported by Doctor Ball. consists in the use of rollers. He reports that " running a corrugated roller over the field as soon as the damage is first discovered seems 55968°— Bull. 66—10 7 88 SOME INSECTS INJURIOUS TO TRUCK CROPS. to have a very good effect. Just why, is not so clear, possibly because it loosens the ground, breaking up any crust that may have formed, and allows all the beets to get through at one time and in this way some of them get ahead of the beetles. The farmers think it kills the beetles. Cleaning up hedge-banks and rubbish around the fields has been recommended and appears to have had a good effect. It is a lamentable fact that a field that is slightly weedy when the beets appear will not be injured as badly as one that is free from weeds, which probably accounts for the fact that replanted beets are rarely destroyed." The use of fertilizers. — Where fertilizers are used the plants are undoubtedly aided in recovering from attack by this flea-beatle, but fertilizers are not remedies. Possibly where mineral fertilizers are applied heavily they might have some effect on the larva?, but it is doubtful if a sufficient amount of an irritant salt would remain in the earth to destroy any large percentage of larvse at the time when those which have just developed from the egg or have just molted are feeding on the roots. It is worth mentioning, however, that Mr. Theo. Eder noticed that when a fertilizer consisting of 3 per cent nitrogen from nitrate of soda, 12 per cent potassium oxid (K20) from muriate (chlorid) of potash, and 9 per cent phosphorus pen- toxid (P205) from superphosphates was applied there were prac- tically no flea -beetles. This fertilizer, however, was considered too expensive, owing to the cheapness of hops in the affected region of British Columbia. Irrigation. — Irrigation has been suggested and, on the authority of Prof. E. G. Titus, the flea-beetle, when it is working on sugar beets, can be driven away during irrigation by disturbing the beets, thus causing the beetles to jump into the water and be swept away.a Tarred catchers. — Tarred sheets, boards, or similar contrivances on the plan of " hopperettes," in use against leafhoppers, have been em- ployed in the infested region for capturing the flea-beetles. Mr. Hulbert reports having destroyed large numbers by catching them on tarred sheets as they fell from the vines after being disturbed. Mr. Quayle also reports success with a " catcher " which he describes substantially as follows: The receptacle used consists of a stout canvas about 3 feet by 4, to which is nailed, on the under side, three strips of boards with one at right angles, to keep the canvas taut. A handle is fastened to two of these strips to project upward and backward, by means of which the apparatus is operated. This is lifted from vine to vine and the beetles jarred off with wisps of hay. Usually two men work together on the same row, the two canvases placed together on each side of the vine. 0 Bui. 67, Bur. Ent., U. S. Dept. Agr., p. 112, 1907. Bui. 66, Pt. VI, Bureau of Entomology, U. S. Dept. of Agriculture. Plate VI. THE HOP FLEA-BEETLE. 89 This method captures a satisfactory percentage of the beetles and should be comparatively inexpensive. But unfortunately the re- peated operations which are necessary bring the cost to a high figure. It cost Mr. Hulbert last year approximately $1.25 per acre for each operation. He went over his vines six times, and some parts of the yard eight or ten times. He expected to go over it at least twice more, so that the total cost would be from $10 to $15 per acre. In figure 19 a portion of a hop field is shown which illustrates the tarred "boards" in place for use. The flea-beetles arc dusted off of the vines upon these tarred receptacles with wisps of hay. as Fig. 19. — Portion of hop field with tarred hoards in place.. Flea-beetles are dusted with wisps of hay from the vines onto tarred hoards. (Original.) described above. All of the vines were tanglefooted, but the flea- beetles went up the poles and crossed over on the wires overhead until the tanglefoot was applied. Plate VII illustrates the method of capturing the hop flea-beetle on tarred horse sledges, also by shaking the vines. Millions were captured in this way. CLEAN CULTIVATION. Frequent stirring of the soil and other cultural operations >eem, as yet, to be of no appreciable help, according to Mr. Quayle, and the kind of soil also seems to have little or nothing to do with the abun- 90 SOME INSECTS INJURIOUS TO TRUCK CROPS. dance of the beetles, which are found in light, sandy, and heavy soils. Mr. Quayle further says: The control measures which have been tried have been necessarily directed entirely against the adult or beetle, and considering the rapid growth of the vines and the continuous appearance of the beetles no effective and practical remedy has yet appeared. With further work on the younger stages it may be possible to find here a vulnerable point of attack. One of the most promising remedies for this as well as other insect pests is the enrolment of clean methods of culture. Since it has been found that the flea-beetles ensconce themselves in any available shel- ter, such as the cracks in the hop poles, even although these may have no bark remaining, it has been thought desirable to dip the poles in a preparation which will not only close the cracks but which will also repel the pests. Fuel oil, a grade of crude petroleum, is being tried, according to Mr. Eder, since it can be purchased as low as 2 cents a gallon. Tar might serve the same purpose and should act as strongly as a repellent and close the cracks more closely and would not be so disagreeable to handle. The poles are dipped into the boiling fuel oil, but the tar would also have to be heated very hot before dipping. It is customary to plow thoroughly and to cultivate where possible so as to keep down the weeds, and this method of tillage must, of course, be continued, as the insects find food in weeds of the kind which have been mentioned in the opening paragraph, viz, dock, lamb's-quarters, pigweed, and the like, and also cruciferous weeds. If, by preventing the insects from hibernating in the hop fields in debris, the fields can be practically freed from them, the next step is to prevent their hibernating in near-by timber, as there can be little doubt that in such places are their favorite winter quarters. It is practicable in many cases to cut down small sections of timber in order to accomplish this purpose. In answer to the question as to the remnants after the hops are picked, Mr. Eder informed the writer that the expedient of cutting the tops and destroying them by burning led to the discovery that the beetles enter into the hollow stalks, remaining in hibernation there in great numbers. With the discovery of this habit he will permit remnants to remain as long as there is any prospect of the insects' trying to obtain winter shelter in them, and then will have all debris burned at about the time of the first frost. One method of destroy- ing field remnants and weeds, by sheep pasturage, is illustrated by Plate VI. The writer has suggested the addition of burlap wrapped about the poles which have been treated with tar or which do not have an odor strong enough to repel the insect. This will attract the insects for hibernation, and can be removed after the first frost, or there- Bui. 66, Pt. VI, Bureau of Entomology, U. S. Dept. of Agriculture. Plate VII. THE HOP FLEA-BEETLE. 91 abouts, and thrown into hot water, and after drying will be available for use in other seasons. If, with another year's experience, we could ascertain how best to control the insect, either by killing the beetles with arsenate of lead or other arsenical, kerosene emulsion, or whale-oil soap, or by destroy- ing the larva? in the ground, the problem would be partially solved. One, two, or perhaps even three of these remedies might be used in combination and excellent results obtained. In any ease, if we can partially control the insects by any one of them we should not forget that cultural remedies, and especially clean culture, are the most valuable remedies that can possibly be employed against insect pests. Indeed, with many species, if cultural practices were properly fol- lowed out, with the cooperation of our neighbors, insecticides would in the course of time, after the balance of nature had been restored, seldom be needed save in case of severe outbreaks, which are likely to occur more or less spasmodically with most of our noxious insects. LITERATURE. A complete bibliography of this species is appended and only a brief review of published accounts need be given. The original description of the species appeared in 1847,1 and it was not until twenty years later that we had any record of the insect's habits. In 1867 Fitch2 wrote a two-page account regarding injury to cucumber, rhubarb, and radish, furnishing notes on a parasitic natural enemy. In 1884 our first account of injury to hops, a brief one, was written by Dr. J. B. Smith.4 These accounts were followed by one from Piper0 on injuries to certain truck crops in Washington State in 1895 and by Doane s of similar injuries in 1900. The writer7 noted the abundance of the species on rhubarb near Washington, D. C., in 1897. Forbes and Hart0 have given a brief account of the insect from the standpoint of its injuries to sugar beet in Illinois, and Fletcher10-11 published fwo accounts of the species in 1904 and 1907, respectively. In 1908 ws s published II. J. Quayle's article,12 in which first mention is made of the larval habits of the insect. BIBLIOGRAPHY. 1. Melsiietmer, F. E.— Proo. Acad. Nat. Sci. Phila., Vol. Ill, p. 166, 1S47. Paginal description from Pennsylvania as Ilaltica pitncl itlata n. sp. 2. Fitch, Asa.— 11th Kept. Ins. Now York, pp. 38-40, 1867. A 2-page account with mention of food plants and a parasite: observed feeding on cucumber, rhubarb, and radish. 3. Fitch, Asa.— lira Ann. Reg. Rural Affairs. 1867 8 9, Vol. v. p. 204, 1^;:;. A brief note, with mention of attack on cucumber and melon. 4. Smith, J. B.— Bui. 4, o, s., Div. Ent., D. S. Dept. Agr.. i». 50, L884, Mere mention of occurrence in hopyardS, where the beetles eat small holes in the leaves, doing no great damage. 5. Horn, G. H.— Trans. Ahum-. Ent Soc., Vol. XVI. pp. 310, 311, -I!*. 1889, Revised technical description, distribution, and systematic bibliography. 92 SOME INSECTS INJTJBJOUS TO TKTJCK CROPS. 6. Piper, C. V.— Bui. 17, Wash. State Agr. Exp. Sta., pp. 55, 56, 1895. Short general account, with list of food plants. Species stated to be " by far the most destructive flea-beetle in the State" [of Washington]. 7. Chittenden, F. H.— Bui. 9, n. s., Div. Ent., IT. S. Dept. Agr., p. 22, 1897. Short note on abundant occurrence on rhubarb near Washington, D. C. 8. Doane, R. W.— Bui. 42, Wash. Agr. Exp. Sta., pp. 11, 12, figs. 2, 3, 1900. A 2-page general account with two original illustrations. 9. Forbes and Hart.— Bui. 60, Univ. 111. Agr. Exp. Sta., p. 472, 1900; 21st Kept. State Ent. Ills., p. 124. A brief account ; on sugar beet in Illinois. 10. Fletcher, Jas. — Kept. Entom. and Bot. Canada for 1903 (1904), p. 177. Mere mention as affecting hops at Sardis, B. C, in noticeable numbers. 11. Fletcher, Jas.— Kept. Entom. and Bot. Canada for 1906 (1907), p. 215. Account of injuries in the Fraser River Valley, B. C, in 1906, with quotations from John Wilson, Agassiz ; Thos. Cunningham, Vancouver ; and H. Hulbert, Sardis, B. C, which include experiences with remedies. 12. Quayle, H. J.— Journ. Econ. Ent., Vol. I, p. 325, October, 190S. A short article, with notes of injury in British Columbia ; account of habits, all stages, including the egg, being taken 3 to 6 inches from the surface of the ground, larvse feeding at the roots of hop And other plants growing in the yards ; list of food plants, and difficulties of applying remedies. SUMMARY. The hop flea-beetle, a minute, black insect, feeds on various succu- lent plants. It does serious damage to hops in British Columbia and less injury to sugar beet and vegetable crops in the Pacific coast region. Its life history is only partially known, but all stages have been found about the roots of hops and the larva probably feeds on most of the same plants as the adult. It is feared that this species may become an important hop-pest in Washington and Oregon, and it doubtless does more injury to beets than is generally accredited to it. Injury is most severe to young plants, but on sugar beet the operations of the beetles throughout the season undoubtedly have a deleterious effect and necessarily decrease the yield. The abundance of the beetles when they appear early in the season on young plants, their constant reappearance, and the constant new growth of the plants from day to day make it difficult to apply direct remedies with more than temporary benefit. Where the hops are sprayed with kerosene emulsion or whale-oil soap for the hop aphis the numbers of the beetles are lessened. Among measures which give promise of value are the institution of clean methods of cultivation, including deep fall plowing, treating hop poles in such manner as to prevent the beetles from hibernating in them, and clear- ing all remnants from fields so as to leave them as bare as possible to prevent the beetles from sheltering there in winter. Arsenate of lead, Paris green, kerosene emulsion, whale-oil soap, and Bordeaux mixture should receive further tests, as should the employment of trap crops in the manner advised in this article. U. S. D. A., Bui. 66, Part VII. I Inly 19. 190v. SOME INSECTS INJURIOUS TO TRUCK CROPS. MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. By F. H. Chittenden. Sc. D.. In Charge of Truck Crop and Stored Prod net Insect Investigation*. SUCCESSFUL USE OF ARSENATE OF LEAD AGAINST THE ASPARAGUS BEETLE. During the first week of June. 1908. Mr. W. A. Orton reported the common asparagus beetle (Crioceris asparagi L.) very injurious at Takoma Park, D. C, and made some experiments with arsenate of lead with complete success. Directions for application, as given in Circular 102 of this Bureau, were followed. The first application was made with 1 pound of arsenate of lead to 20 gallons of water and the second a week later, as the plants had grown rapidly in the mean- time and a great many new larva? had hatched. The second appli- cation was made at the rate of 1 pound to 15 gallons of water. The first application destroyed most of the insects, but after a few days a considerable number had developed. These appeared to have been all killed the day after the second spraying. Xeither spraying seemed to injure the plants in the least, but the liquid adhered in fine drops to the foliage and was visible there for some time. An unsprayed plat on a neighbor's place was considerably7 injured by these insects, and up to July 1 no more had appeared on Mr. Orton's crop. He pronounced the treatment very effective. The work was done with a compressed- air machine or autospray. Mr. Edward A. Eames, Buffalo, X. Y.. writing of the value of arsenate of lead as a means of combating the common asparagus Note. — The accompanying Tart VII includes short notes on sonic of the insects which have been treated in earlier parts of this bulletin and notes en two insects not hitherto recorded as injurious in the United States. To the former class belong notes on the asparagus beetles and the asparagus miner. species considered more in detail in Tart I. pages 1-10. and notes on water- cress insects in addition to what has been published in Part II. pages n -Jo. To the second class belong notes on the injurious occurrence o\' the pea moth in the United States and a short account of a new western FOOt-maggOt — P. EL G. 94 SOME INSECTS INJURIOUS TO TRUCK CROPS. beetle, stated that the larva? of this species threatened to devour his this year's spring-set asparagus to the ground. But after one thor- ough spraying with arsenate of lead it was difficult to find any but dead larvae on the plants. Successive sprayings were of course neces- sary, because the beetles continued to come from neighboring gardens to deposit eggs on the plants and because the developing plants con- tinually presented fresh unsprayed foliage for larval food. Mr. Eames stated positively that arsenate of lead adhered well, even through several rains, just as its various promoters claimed — a fact which justifies its use in any case even at more initial cost than other poisons which might be used. He also expressed the view that asparagus growers generally should be impressed with the fact that, because of the tendency to spray only once, additional informa- tion should be given of the value of extra applications. In conclusion, he stated that he believed arsenate of lead was a specific for this class of insects. Our correspondent is undoubtedly right. It seems to be as nearly a specific for asparagus beetles as anything that can be obtained, provided it is applied according to directions and that applications are repeated as often as necessary. The trouble is that many truck growers, after spraying a single time, consider that the matter should then be dropped, and if the desired result is not produced, i. e., if the trouble is not wholly stopped, the spraying is condemned or at any rate the insecticide is discontinued, while all that is necessary for the entire season is a second or third application. A NOTE ON THE ASPARAGUS MINER. The asparagus miner (Agromyza simplex Loew) was reported by Mr. I. J. Condit in the vicinity of Antioch, Cal., August 19, 1908, where the common asparagus beetle was also abundant. The miner was said to be equally numerous and stalks showing infestation were received. The miner-infested stalks could generally be detected by their roughened appearance near the ground. This species was also taken by Mr. Condit at Oakley and it seems probable, since the common asparagus beetle is found in both local- ities, that it is becoming generally distributed in California. In one place at Oakley Mr. Condit observed the miner quite common on some stalks, but it did not appear to be equally common over the entire ranch. During October, 1908, the writer observed this species well estab- lished on asparagus in the vicinity of Portsmouth, Va. In October, also, Mr. J. B. Norton reported very severe injury to asparagus in the vicinity of Concord, Mass. The roots of the plants were not only girdled, but the miners worked up the stalks some inches above the ground. MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. 95 INJURIOUS OCCURRENCE OF THE PEA MOTH IN THE UNITED STATES. Prominent among the injurious occurrences of the year 1908 was the discovery of the pea moth (Enarmonia nigricana Steph.) for the first time in the State of Michigan. August 10 we received from Mr. J. E. W. Tracy, Bureau of Plant Industry, specimens of the larva of this species and its work in growing peas and pods from Charlevoix, Mich. Mr. Tracy wrote that he obtained the specimens on that day and some days earlier and that Mr. E. W. Coulter and others in that vicinity knew nothing of the identity of this insect, which was causing them considerable concern. The caterpillar first showed itself in very small numbers four or five years before, but it had increased rapidly until the year of writing, when 15 per cent of the peas were ruined. The insect appears to start operations by eating the embryo stem and then moves along the pod until it makes its exit and dis- appears. Early varieties of peas were the worst sufferers in the affected district. At the time of writing our correspondent found a less number of living larvse than previously. This appears to be the first record of the appearance of this insect in the United States, although it has been known as a pest in Canada for several years and has undoubtedly been present in our Northern States, where peas are grown, without having been recognized as anything new or unusual. A two-page account of this species has been published by the writer in Bulletin No. 33, pages 96-98, which includes a brief illustrated description of the moth and larva and a consideration of the distri- bution, nomenclature, history, habits, and remedies. This insect first came to notice near Toronto, Ontario, in 1893, and notices of its ravages in Canada were given in several subsequent years by the late Dr. James Fletcher in his report as entomologist and botanist of the Dominion of Canada. It is an importation from the Old World and is well established in New Brunswick and Nova Scotia as well as in Ontario, and is also recorded from Manitoba. The name of this species was omitted from the Dyar catalogue of Lepidoptera, but is included in Smith's Check List of Lepidoptera under No. 5702. In most publications the species is mentioned as Semasia nigricana. A NEW WESTERN ROOT MAGGOT. August 10, 1907, Mr. E. M. Ehrhorn sent from San Francisco, CaL, some radishes, the roots of which were affected by a maggot. The adults were reared September 3 to 20 and were referred to Mr. D. W. Coquillett for identification. They were first mistaken for Pegomya cepetorum, because of the very close relation of the two species, but 96 SOME INSECTS INJURIOUS TO TRUCK CROPS. when more material of both sexes was obtained they were seen to be different. Mr. Coquillett states that some individuals have the bristles practically as in eepetorum, but in the males the median black stripe of the abdomen is continuous. This material corresponds so well with Stein's description0 of Chortophila planipalpis as to leave no reasonable doubt of the species. The type locality is Idaho. The insect will therefore be known as Pegomya planipalpis Stein, and may be called the western radish maggot. Another lot of the maggot was received from the same source October 1, larvae and pupae both being present. From this lot adults issued November 1 to 21. November 21, 1908, we received from Mr. Charles Heise, Aber- deen, Wash., a section of turnip mined by larvae which are probably of this species, as also a number of puparia. Our correspondent stated that his observations showed that the maggot works on onions as well as on turnips. As we do not know to the contrary, and do not know positively of the occurrence of any onion maggot in that State, this surmise may be correct. It remains to be verified or dis- proves The seed-corn maggot (Pegomya fusciceps Zett.) occurs in that region and is more apt to be the onion-feeding species. Two natural enemies of this radish maggot have come under ob- servation and have been identified by Mr. J. C. Crawford, as follows : Aphtvreta sp. — September 3, 1908, many braconids of a species of the genus Aphcereta emerged from material in which this root- maggot was breeding in infested radish from San Francisco, Cal. It is a small species, shining black in color, with dusky wings and yellow legs. In some specimens there are 21 joints to the antennae on one side and 22 on the other. It is very similar to the type of muscce, but is larger. Polypeza sp. — This species was reared from its host October 10, 1907, and appears to be undescribed. NOTES ON WATER-CRESS INSECTS. The water-cress leaf -beetle. — May 2, 1907, Mr. J. W. Bryan brought to this office from Halltown, W. Va., specimens of the water-cress leaf-beetle (Phcedon aeruginosa Suffr.), present in the beetle and larval forms, the larvae at that time about half grown. The beetles were beginning to die and a fungus attack was noticed when received. Numerous individuals of the beetle and one larva were parasitized by the fungus. The fungus was tentatively determined by Mr. Haven Metcalf, Bureau of Plant Industry, as Entomophthora splicer osperma. If this identification is correct, there can be no doubt that the fungus attacked the insect before death, and may therefore be a factor of value in its natural destruction. « Berl. Ent. Zeitschr., Vol. XLII, pp. 234-235, 1897. MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. 97 Since the publication of the writer's preliminary articles on the water-cress leaf -beetle and sowbug in the present bulletin (pp. 11-20) it has been noticed that earlier accounts of the related European PJuedon betulce L., known as the mustard beetle and ': blackjack, *? were made by Miss E. A. Ormerod, who furnished several references with illustrations in her manual." From this account it appears that injury was first noticed, at least in England, in 1854, to white mustard crops near Ely. Another account of this insect is given in the same author's report for 1886. b The water-cress sowbug. — April 16, 1907, Mr. C. A. Killinger. Ship- pensburg, Pa., sent specimens of the water-cress sowbug (Mancasellus brachyurus Harg.) in different stages, stating that it was destroying his water cress, working on the leaves under water, cutting them close to the stem. If the cress is light or does not grow fast, as happens in winter, they also work on the stems and roots, cutting the plants loose and causing them to float downstream. Our correspondent thought that this species was brought to that section from Virginia. Experiments conducted with lime in a small spring the previous summer succeeded in killing most of the sowbugs, but plenty of them remained at the time of writing. The lime, however, burned the cress, causing it to turn yellow. December 23, 1908, Mr. F. W. Houston, a grower and shipper of water cress at Lexington, Va., wrote of this species, inquiring for literature and a remed}^. He stated that he had a spring under culti- vation that was infested with the water-cress sowbug, and later — March 11, 1909 — he sent specimens. In this connection he wrote as follows : I have a spring under cultivation which has heen infested by them for several years. I fought them for a time by putting the water into ditches and exposing the rest of the cress bed to the sun. In these ditches I would make frequent applications of lime; this, of course, was done during the early summer, after the shipping season closes. It seems to kill all of the sowbugs. but when I put the water into the beds and reset the cress, hauling it from an uninfected spring, it was not long until the " bugs " were again noticed, and in a short time they were as thick as ever. Mr. Houston was advised that in the ease of the old beds the water should be drawn or turned off and that the cress should be completely destroyed and the spring reset with uninfested ere—. a Manual of Injurious Insects and Methods of Prevention. London. 1890, pp. 151-156. 6 Report on injurious Insects for 1886, pp. 59-60. NDEX Page. Actinotia derupta, bibliographic reference 70 Agallia bigelovise on sea-blite (Dondia) 50-51 sugar beet 50-51 cinerea on sugar beet 50-51 novella on sugar beet, habits 51 quadripunctata on sugar beet, habits 51 sanguinolenta on sugar beet 50-51 uhleri on sugar beet 50-51 Agromyza simplex 1-5 biological notes 2-3 descriptive 1-2 distribution 2 historical notes 2-3 injury, recent 3-4 on asparagus in California, Massachusetts, and Virginia 94 remedial measures 4-5 Allygus sp., of Bruner, probably Eutettix strobi 49 Amaranth, spiny, food plant of Prodenia eridania 53, 58-60, 62, 69 Amaranthus spinosus. (See Amaranth, spiny.) grsecians, food plant of Psylliodes punctulata 77 retroflexus, food plant of Psylliodes punctulata 77 Apateticus (Eupodisus) mucronatus, enemy of Prodenia eridania 64 Aphaereta sp., parasite of Pegomya planipalpis 96 Aphiochxta nigriceps eating pupae of Prodenia eridania 63 Apple, food plant of Cleora pampinaria 24, 25 Empoasca 51 Army worm, semitropical. (See Prodenia eridania.) Arsenate of lead against common asparagus beetle 8-9, 93-94 cranberry spanworm 26-27 hop flea-beetle 83-85. semitropical army worm 65-69 striped garden caterpillar 32 and Bordeaux mixture against hop flea-beetle 83-84 striped garden caterpillar 32 resin-fishoil soap against hop flea-beetle 83 M soap against common asparagus beetle 8-9 Arsenite of copper, adhesive, against semitropical army worm I analysis 69 lime with soda against hop flea-beetle v - Asclcpias incarnata. (See Milkweed.) Asparagus beetle, common. (See Crioceris asparagi.) twelve spotted. (See Crioceris U-punctata.) beetles, notes on distribution and destructive occurrences 6-10 99 100 SOME INSECTS INJURIOUS TO TRUCK CROPS. Page. Asparagus, food plant of Agromyza simplex 1-5 Cleora pampinaria 21, 25 Crioceris asparagi 6-8 12-punctata 9 Mamestra legitima 28-32 miner. (See Agromyza simplex.) Atriplex confer tifolia, food plant of Eutettix clarivida 50 insana 50 pauperculata 50 tenella 35 food plants of Eutettix albida 50 Ball, E. D., paper, The Leafhoppers of the Sugar Beet and their Relation to the "Curly-leaf " Condition 33-52 Beet, food plant of Eutettix seminuda 50 Prodenia eridania 61 Psylliodes punctulata 77, 79 leafhopper. (See Eutettix tenella.) sugar, "curly-leaf " condition with relation to Eutettix tenella.. 33-48, 52 leafhoppers 33-52 food plant of Agallia bigelovix 50-51 cinerea 50-51 novella 51 quadripunctata 51 sanguinolenta 50-51 uhleri 50-51 Empoasca 51-52 Eutettix clarivida 50 scitula 44-45, 49-50 strobi 44-45, 49 tenella 35 Psylliodes punctulata 71, 74-77, 92 Blackberry, food plant of Cleora pampinaria 24, 25 Mamestra legitima 30, 32 "Blackjack." (See Phsedon betulx.) "Blight" of sugar beet, characteristics 44-46 relation to leafhoppers 33-52 or "curly-leaf" of sugar beet around Spreckels, Cal., not work of Eutettix tenella 46 "Blue beetle." (See Phsedon armoracix.) Boards, tarred, against hop flea-beetle 83, 88-89 Boarmia collecta= Cleora pampinaria 22 fraudulentaria= Cleora pampinaria 22 frugallaria, bibliographic reference 27 = Cleora pampinaria 22 pampinaria, bibliographic reference 27 = Cleora pampinaria 24 sublunaria, bibliographic reference 27 = Cleora pampinaria 22 Bordeaux mixture, deterrent against hop flea-beetle 87, 92 with arsenate of lead against hop flea-beetle 83-84 striped garden caterpillar. . . 32 Paris green against hop flea-beetle 83-85 Bursa bursa-pastoris, food plant of Psylliodes convexior 81 INDEX. 101 Cabbage, food plant of Mamestra legitima 30, 32 Phxdon armoratix 18 Prodenia eridania 61 ornithogalli 30 Psylliodes punctulata 77 Callitricha verna, food plant of Phxdon armoratix 19 Calosoma sayi, enemy of Prodenia eridania 64 Cardamine amara, food plant of Phxdon armoratix 19 "Careless weed." (See Amaranth, spiny.) Carp, suggested use against water-cress sowbug 15 Carrots, food plant of Prodenia eridania 6 1 Castor-oil plant, food plant of Prodenia eridania 60 Catfish of no avail against water-cress leaf -beetle 20 suggested use against water-cress sowbug 15 " Chalcidian' ' parasite of Psylliodes punctulata recorded by Fitch 82-83 Chclonus sp. , parasite of Prodenia eridania 63 Chenopodium album, food plant of Eutettix strobi 49 Psylliodes punctulata 76 food plant of Eutettix scitula 44-45. 49-50 strobi 44—45 Psylliodes punctulata 77 rurale, food plant of Psijlliodes punctulata 76 Chittenden, F. H., and Russell, H. M., paper, "The Semitropical Army Worm (Prodenia eridania Cram .)*'... 53-70 paper, "Miscellaneous Notes on Truck-crop Insects" 93-97 • Notes on the Asparagus Beetles' ' 6-10 "The Asparagus Miner (Agromyza simplex Loew > ". . 1-5 "The Cranberry Spanworm (Cleora pampiuaria Guen.)" 21-27 "The Hop Flea-beetle (Psylliodes punctulata Melsh.)" 71-92 "The Striped Garden Caterpillar (Mamestra legitima Grote)" 28-32 "The Water-cress Leaf-Beetle (Phxdon aeruginosa Suffr.) " 16-20 "The Water-cress Sowbug (Mancasellus brachyvrus Harger) " 11-15 ( 'h lurid of lime, suggested remedy against water-cress sowbug 14 Chortophila planipalpis=Pegomya planipalpis Clean cultivation against hop flea-beetle 89-91. 92 Cleora pampinaria 21-27 bibliography 27 biologic literature 24 descriptive 21 23 distribution 23-24 food plants 25 26 larva , description 22 life history 26 moth, description 21 22 nal oral enemies 26 pupa, description remedies 2 synonyms 22 unpublished office notes 25 102 SOME INSECTS INJURIOUS TO TBUCK CEOPS. Page. Cleora tinctaria= Cleora pampinaria 22 Clover, red, food plant of Cleora pampinaria 25 Psylliodes punctulata 77, 79 white, food plant of Psylliodes punctulata 77, 79 Jochlearia armoracia, food plant of Phxdon armoracise 19 Collards, food plant of Mamestra legitima 30, 32 Prodenia eridania 53, 69 ornithogalli 30 Cotton cutworm. (See Prodenia ornithogalli.) food plant of Cleora pampinaria 24-26 Cowpeas, food plant of Prodenia eridania 53, 60, 69 Cranberry, food plant of Cleora pampinaria 21, 24, 25 spanworm. (See Cleora pampinaria.) Cress, food plant of Phsedon armoracise 18 water. (See Water cress.) Grioceris asparagi 6-9 control with arsenate of lead 93-94 remedies 8-9 12-punctata 9-10 larva, young, description 10 Crucifers, preferred food plants of Psylliodes 81 Cucumber, food plant of Psylliodes punctulata 77 Cultural methods against beet leafhopper 48 hop flea-beetle 87-91 "Curly-leaf" of sugar beet around Spreckels, Cal., not work of Eutcttix ten- ella 46, 51-52 characteristics 44— 46 conclusions 52 relation to Eutettix tenella 33^18, 52 leafhoppers ' 33-52 Cutworm, cotton. (See Prodenia ornithogalli.) Cymatophora pampinaria, bibliographic reference 27 = Cleora pampinaria 22 Deromyia ternata, enemy of Polistes annularis 64 Dissosteira Carolina affected by fungus 31 Dock, food plant of Psylliodes punctulata 77, 79 Dondia, food plant of Agallia bigelovise 51 Eutettix tenella 35 Ducks against water-cress sowbug 14 suggested remedy against water-cress leaf -beetle 20 Dyar, H. G., technical description of the egg and larval stages of Prodenia eridania 55-57 Eggplant, food plant of Prodenia eridania 53, 62, 69 Empoasca, association with so-called "curly-leaf" of sugar beet at Spreckels, Cal 46, 51-52 on sugar beet, habits, remedy 51-52 Empusa sp. , fungous enemy of Prodenia eridania 65 Enarmonia nigricana, injurious occurrence in United States 95 Entomophthora sphserosperma, fungous enemy of Phsedon aeruginosa 96 Epitrix, host of Perilitus schwarzii (?) 82 Estigmene (Leucarctia) acrsea affected by fungus 31 Eutettix albida on Atriplex 50 clarivida on sugar beet, appearance and habits 50 INDEX. 103 Page. Eutettix insana on Atriplex 50 nigridorsum on Ilelianthus, discoloration and distortion of leaves re- sulting 44-45 pauperculata on Atriplex 50 scitula on Chenopodium and sugar beet, discoloration and distortion of leaves resulting 44-45 sugar beet, appearance and habits 49-50 seminuda on beet, appearance and habits 50 straminea on Helianthus, discoloration and distortion of leaves result- ing r 44-45 stricta, bibliographic reference 48 near relative of Eutettix tenella 50 strobi, habits 44-46 on Chenopodium and sugar beet, discoloration and distortion of leaves resulting 44-45 sugar beet, appearance and habits 49 tenella, adult, description 35 at Lehi, Utah 36-37, 38-40 Maroni and in the Cache Valley, Utah 38 Monroe, Utah 38 bibliographic references 48 cage experiments, Lehi, Utah 38-40 descriptive 35 distribution 36 economic relations 41-47 summary 47-48 eggs, description 35 food plants 35 in Oregon, Idaho, and California 46-47 life-history studies 3B-40 summary 40 nymphs, description 35 relation to "curly-leaf" condition of sugar beet 33-48, 52 remedies, proposed 47-48 Exorista boarmix, parasite of Cleora pampinaria 26 Fertilizers against hop flea-beetle 88 Fish against water-cress sowbug 11-1") suggested remedy against water-cress leaf-beetle 20 Flea-beetle, hop. (See Psylliodes punctulata.) European. (See Psylliodes attcnuata.) potato, European. (See Psylliodes affinis.) punctulated. (See Psylliodes punctulata.) rhubarb. (See Psylliodes punctulata.) small-punctured. (See Psylliodes punctulata.) " Flea," name for Psylliodes punctulata in the West 71 Fundulus diaphanus, F. dispar, and F. notatus, suggested use against water- cress sowbug L5 Fungous disease of Prodenia eridania 65 diseases of Mamcstra Iccjitima 31 enemy of Phasdon nruginosa 96 Garden caterpillar, striped. (See Mamcstra Icgitima.) Geranium, food plant of Cleora pampinaria 24, 25 Goldenrod, food plant of Mamcstra legitinui 30. 32 55968°— Bull. 66—10 8 104 SOME INSECTS INJURIOUS TO TRUCK CROPS. Page. Grass, food plant of Mamestra legitima 32 Greasewood. (See Sarcobatus.) Guava, food plant of Cleora pampinaria 25 Haltica punctulata, bibliographic reference 91 Helianthus, food plant of Eutettix nigridorsum 44-45 straminea 44-45 Hickory, food plant of Cleora pampinaria 25 Honey locust, food plant of Cleora pampinaria 25 Hop flea-beetle. (See Psylliodes punctulata.) European. (See Psylliodes attenuata.) "Hop-flea," name for Psylliodes punctulata in the West 71 "Hopper-dozer." (See Tar pan.) "Hopperettes." (See Tarred catchers.) Hop plant, food plant of Psylliodes punctulata 71-92 Horseradish, food plant of Phsedon armoracix 19 " Ichneumon," parasite of Prodenia eridania 58, 64 Irrigation against beet leafhopper 48 hop flea-beetle 88 as affecting "curly-leaf " condition of sugar beet 41-43 Kerosene emulsion against beet leafhopper 43, 47-48 Empoasca on potatoes 52 hop flea-beetle. : 85-87, 92 Killifishes, fresh water. (See Fundulus diaphanus, F. dispar, and F. notatus.) Kohlrabi, food plant of Phsedon armoracix 18 Lamb's-quarters. (See Chenopodium.) Leaf-beetle, water-cress. (See Phsedon aeruginosa.) Leafhopper, beet. (See Eutettix tenella.) Leafhoppers and their relation to "curly-leaf " condition of sugar beet 33-52 Leucania nigrofascia, bibliographic reference 70 Lime, air-slaked, with Paris green, against hop flea-beetle 83 remedy against water-cress sowbug, burns cress 97 Limnerium sp., parasite of Prodenia eridania 63 Locust, Carolina. (See Dissosteira Carolina.) Mamestra legitima 28-32 biologic notes 29-31 control methods 32 descriptive 28-29 habits, summary 32 larva, description , 28-29 moth, description 28 natural enemies 31 pupa, description 29 Mancasellus brachyurus 11-15 control methods 12-15, 97 descriptive 11-] 2 injuries and remedies 97 injurious occurrences 12 Mangel, food plant of Psylliodes punctulata 79 Mechanical methods against hop flea-beetle 87-89 Meteorus sp., host of Spilochalcis spp 63 parasite of Prodenia eridania 63 Milkweed, food plant of Mamestra legitima 30, 32 [NDEX. 105 Mustard beetle. (See Phxdon armoracise and /'. betuUe.) common black, food plant of Psylliodes punctulata 71 75, 77 food plant of Phxdon armoracix 18 Psylliodes punctulata 77 hedge, food plant of Psylliodes punctulata 7 : white, food plant of Phxdon belulx 97 Nasturtium officinale. (See Water-ci Nettle, food plant of Psylliodes punctulata 7 Noctua xylina, bibliographic reference 27 Okra, food plant of Prod( n ia eridan ia Oph ion tityri, parasite of Prodenia eridan ia Orange, food plant of Cleora pampinaria 25 Paris green against common asparagus beetle 8 cranberry spanworm _ hop flea-beetle 8 Bemitropical army worm 65-69 striped garden caterpillar 32 and Bordeaux mixture against hop flea-beetle - flour against water-cress leaf-beetle 19 plaster or air-slaked lime against water-cress leaf-beetle 19 water against water-cress leal-beetle 19 dry, with air-slaked lime, against hop flea-beel le - Pea moth. (See Enarmonia nigricana.) Pear, food plant of Cleora pampinaria 24, 25 Peas, food plant of Enarmon ia n igricana 95 Mamestra legitima 23, Proden ia orn ithogalli 30 Pegomya planipal pis on radish 95-96 Pepper, food plant of Prodi n ia t ridan ia 53, 69 Perilitus sckwarzii (?), parasite of Epitrix Phyllotreta 82 Psylliodes punctulata Phxdon xruginosa 16 20 beetle description ». Hi- 17 control methods 19-20 descriptive 16-18 sr, description 17 fungous enemy 96 habits Lg injurious occurrence 16 larva, description 17 literature L8 Plagiodera viridis a synonym L8 pupa, description armoracia . habits 18 mi synonyms !> betul%= Phxdon armoracise L8 I" on white mustard 97 cochlearix Fab., distinct from Phsedon armoracia Phalxna Phytolacca . bibliographic reference 70 = Prodt iiia eridania 57 Plih psius irroratus, mistaken determination oi Eutettix strobi 49 Phyllotreta, host of Perilitus sckwarzii (f) Phytolacca decandtra. {See Poke weed.) 106 SOME INSECTS INJURIOUS TO TRUCK CROPS. Pigweed. (See also Amaranthus retroflexus .) food plant of Psylliodes punctulata 79 Plagiodera cochlearix Panz. , G y 11. =Phssdon armoracise 18 viridis=Phsedon aeruginosa 18 Podisus maculiventris, enemy of Prodenia eridania 64 Poke weed, food plant of Prodenia eridania 53, 58, 61-62, 69 moth, name for Prodenia eridania 57 Polistes annularis, enemy of Prodenia eridania 64 Polypeza sp., parasite of Pegomya planipalpis 96 Pontia rapae, enemy of Prodenia eridania 64 Potato flea-beetle, European. (See Psylliodes affinis.) food plant of Prodenia eridania 53, 58-59, 69 Psylliodes punctulata 77, 79 "Pretty cutworm," manuscript name for Mamestra legitima 30-31 Prodenia eridania 53-70 bibliographic list 70 control methods 65-69 descriptive 54-57 distribution 57 early records 62 egg, description 54 fungous disease 65 generations 62-63 history 57 injury to truck crops 53-70 larval stages, description 55-57 life-cycle periods 62-63 literature 57-58 moth, description 54 natural enemies 63-65 origin 57 parasites 63 predaceous enemies 64-65 Prodenia nigrofascia Hulst a synonym 54 pupa, description ! 55 summary 69 nigrofascia of Hulst —Prodenia eridania 54 orniihogalli, association with Mamestra legitima in damage to garden crops 30 phytolaccse, bibliographic reference 70 Psylliodes affinis, the European potato flea-beetle 81 attenuata, the European hop flea-beetle 81 chrysocephala on edible crucifers in Europe, habits 81-82 convexior, comparison with Psylliodes punctulata 73 on Bursa bursa-pastoris 81 notes on various species 81-82 punctulata 71-92 adult, habits 79-80 bibliography 91-92 control methods 83-91 descriptive 72-73 INDEX. 107 Page. Psylliodes punctulata, development 81 distribution 73 egg 80 food habits 76-77 generations 78 habits 79-81 host of Perilitus schwarzii (?) 82 injuries, recent 73-76 larva, habits 80 life history. . . . .' 79-81 literature 91 local conditions affecting abundance 82 methods of attack 76-77 pupa 80-81 summary 92 Quayle, H. J., account of life history and habits of Psylliodes punctulata 79-81 Radish, food plant of Pegomya planipalpis 95-96 Psylliodes punctulata 77 Rape, food plant of Mamestra legitima 30, 32 Prodenia ornithogalli 30 "Raps-erdfloh." (See Psylliodes chrysocephala.) Resin-fishoil soap with arsenate of lead against hop flea-beetle 83-84 striped garden caterpillar 32 soap and arsenate of lead against common asparagus beetle 8-9 wash against hop flea-beetle 86 Rhubarb flea-beetle. (See Psylliodes punctulata.) food plant of Psylliodes punctulata 71, 77 Rolling, remedy against beet leafhopper 48 hop flea-beetle 87-88 Root maggot, a new one from the West 95-96 Rose, food plant of Empoasca 51 Rumex. (See Dock.) Russell, H. M., and Chittenden, F. H., paper, "The Semitropical Army Worm (Prodenia eridania Cram . ) " 53-70 Russian thistle. (See Thistle, Russian.) Ruta-baga, food plant of Mamestra legitima 30, 32 Prodenia ornithogalli 30 Salt-marsh caterpillar. (See Esligmene [Leucarctia] acrsea.) Sarcobatus, food plant of Eutettix tenella 35 Scheele's green against hop flea-beetle 8 K Schilbeodes. (See Catfish.) Sea-blite. (See Dondia.) Semasia nigricana= Enarmonia nigricana 95 Shad scale. (See Atriplex confer ti/olia.) Shepherds' purse. (See Bursa bursa-pastoris.) Sheets, tarred, against hop flea-beetle 83 vx Snuff, against hop flea-beetle Solanum, wild, food plant of Prodenia eridania Solidago spp. (See Goldenrod.) Sowbug, water-cress. (Sec Mancasellus brachyurut.) Spanworm, cranberry. (See Chora pampinaria.) 108 SOME INSECTS INJURIOUS TO TRUCK CROPS. Page. Spilochalcis spp., parasites of Meteorus 63 secondary parasites of Prodenia eridania 63 Sporotrichum minimum, fungous enemy of Mamestra legitima 31 Starwort, water. (See Callitricha verna.) Stiretrus anchor ago, var. diana, enemy of Prodenia eridania 64 Strawberry, food plant of Cleora pampinaria 21, 24, 25 Striped garden caterpillar. (See Mamestra legitima.) Sulphate of copper, suggested remedy against water-cress sowbug 14 Sweet potato, food plant of Prodenia eridania.. 53, 59-62, 69 Tar pan, or tarred wings, against beet ieafhopper 48 Tarred catchers against hop flea-beetle 88-89 Thamnotettix. tenellus, bibliographic references 48 Thistle, Russian, food plant of Eutetlix tenella 35 Tobacco extract against hop flea-beetle 86 food plant of Mamestra legitima 30, 32 powdered, against hop flea-beetle 83 Tomato, food plant, of Prodenia eridania 53, 58, 69 Trap crops against hop flea-beetle 87, 92 plants in control of asparagus miner 4-5 Truck-crop insects, miscellaneous notes 93-97 Tumbleweed. (See Amaranthus gracious.) Turnip, food plant of Mamestra legitima 30, 32 Prodi a ia or u iihogalli 30 Psylliodes punctulata 77, 79 mined probably by Pegomya planipalpis 96 Veronica beccabunga, food plant of Phasdon armorociie 19 Verticillium, fungous enemy of Dissostt ira enrol i na 31 Estigmene (Leucarctia) acraea 31 Mamestra L gitima 31 Violet, food plant of Mamestra legitima 30, 32 Water-cress, burned by lime used as insecticide against sowbug 97 food plant of Mancasellus brachyurus 11-12 Phaedon aeruginosa 16 armoracix - - ■ 19 insects, notes 96-97 leaf-beetle. (See Phsedon aeruginosa .) method of growing to avoid damage by sowbug 13-14 sowbug. (See Mancasellus brachyurus.) Whale-oil soap against hop flea-beetle 85-87, 92 Willow, food plant of Cleora pampinaria. 24, 25 Winthemia quadripustulata, parasite of Prodenia eridania 63 Xylomiges phytolaccae, bibliographic reference 70 o