945 9 C5 py 2 NITED STATES DEPARTMENT OF AGRICULTURE BULLETIN No. 891 ContribntioR from the Bureau of Entomology L. O, HOWARD, Chief Washington, D. C. PROFESSIONAL PAPER July 28, 1922 THE GREEN JUNE BEETLE By F. H. CHITTENDEN, Entomologist in Charge, and D. E. FINK, Entomological Assistant, Truck Crop Insect Investigations CONTENTS Introduction Classification Descriptive Technical Description Distribation and InJHiieus Occarrence Nature of Injury Page 1 2 3 4 7 8 Page Life History and Habits 17 History and Literature 28 Control by Natural Agencies 81 Methods of Control 37 General SBmmary 48 Literature Cited 49 WASHINGTON GOVERNMENT PRINTING OFFICE 1922 Worm.*;- , . I OCT 1814^2 ■> II nil)——— nimww niirfi UNITED STATES DEPARTMENT OF AGRICULTURE ^"U^^\^t. BULLETIN No. 891 Contribution from the Bureau of Entomology L. O. HOWARD, Chief yu^'^«-ru Washington, D. C. PROFESSIONAL PAPER July 28, 1922 THE GREEN JUNE BEETLE.' By F. H. Chittenden, Entomologist in Charye, and D. E. Fink, Entomological Assistant. True]: (^rnp Insect Inrestigntions.' CONTENTS. Introduction Classification Descriptive Technical description Distribution and injurious occur- rence Nature of injury Page. Page. Life history and habits 17 History and literature 28 Control by natural agencies .31 Methods of control 37 General summary 48 Literature cited 49 INTRODUCTION. The green June beetle is one of the best known of Southern insects and is quite common in the Eastern States from New Jersey and southern Illinois southward. It occurs also somewhat commonly on Long Island, in southern Connecticut, and in the neighborhood of New York City. Injuries by this insect were at one time errone- ously believed to be practically confined to the beetle, since the larva? feed normally and largely on humus or mold, or soil rich in decaying vegetable matter, and in stable and lot manure. The beetles injure fruits of various kinds, including grapes, peaches, raspberry, blacld^erry, apple, pear, quince, plum, prune, apricot, and nectarine, and. frequently obtain nourishment as well on the sap of oak, maple, and other trees, and on the growing ears of ^ Cotinis niiida L. (formerly known as AUorhin said is that C. mutabilis is, in the great majority of its Individuals, larger and broailer. The shape of the olypeal horn is very variable, and its varieties do not correspond with variations in size, breadth, and color, large and robust specimens of the typical mutnhiUs having the horn either dilated toward the apex, parallel-sided, or triangular, and the same diversities may be seen in small and slender oblong examples of C. sobrina. It is the same with regard to form and color; for it is far from the case that the large and broad examples (C. mutabiJis) only are unicolorous ; smaller and narrower indi\ iduals exist equally unicolorous and of nearly all the color-varieties displayed by the larger set. It Is true that the variegated varieties described by Burmeister under C. sobrina are, as a rule, smaller than the others ; but they are connected by the most finely graduated series of variations, so that it is impossible to draw a distinction between the two series. The case is a very difficult one to deal with. It would not be satisfactory, and scarcely, practicable, to include under one specific diagnosis all the numerous varieties, some of which are possibly local, thus presenting an interesting study to future collectors and students ; the better course seems to be to treat the more distinct separately, giving the locali- ties of each. DESCRIPTIVE. The beetle (fig. 1) is larger and more robust than the common brown May and June beetles (Phyllophaga), measuring from three- fourths to a full inch or more in length, and about one-half inch wide. The color varies from dull brown with irregular stripes of green to beautiful uniform velvet green, the margins of the body being usually light brown varying to orange Aellow. The lower surface is metallic greenish or jellow. or metallic dark brown with a yellow- green tinge. The full-grown larva is illustrated in figure 2 and Plate II. When com- pared with that of Phyllophaga (fig. 3). it will be noticed that the former is stouter with shorter legs. The pupa, which is also stouter, is shown alone and Avithin its pupal case or cocoon in Plate III, A, B. The pupa of Phyllophaga (PI. Ill, C) differs from the pupa of Cotinis in that the pupa of the former is not encased in a regular cocoon. Fig. 1. — Adult of green June beetle {Cotinis nitida) of a type show- ing narrow margin about elytra and narrow margin on anterior half of thorax. One-third enlarged. HABITS DIFFERENT FROM THOSE OF WHITE GRUBS. The green June beetle differs from the May beetles in habits, be- ing strictly diurnal and most active in the heat of the day, whereas '4 BULLETIN 891, U. S. DEPARTMENT OF AGEICULTURE. the typical winged Phyllophaga is nocturnal. There is a still more striking difference in that the larva of the green June beetle travels on its back, whereas that of Phyllophaga either progresses on its side or, where possible, on the abdomen with the aid of the legs. The larva (fig. 2), particularly when mature, differs from the com- mon white grub of the genus Phyllophaga in being larger, and pro- Fir,. 2. — Full-grown larva of green .Tune beetle in natural position crawling on it.s back. Twice natural size. portionately so, as regards the size of the adults. It is also more robust and more nearly cylindrical ; its legs are considerably shorter and its mandibles and other mouth parts smaller. It differs also in the possession of stiff ambulatory bristles, which more or less closely cover the dorsum and enable the insect to crawl, not on its side, as is the case with the Phyllophaga larva, but upon its back. This is ac- complished by alternate contraction and expansion of the segments of the body, the stiff dorsal hairs materially assisting progress. The speed is prob- ably more rapid than that of any other known genus of the Scarabaeidae oc- curring in the United States. Indeed, it progresses on its back at about the same rate as the hairy caterpillars do on their legs and prolegs, and in a simi- lar manner. Fig. 3. — Time white grub {Phyl- lophaga sp.) which does not crawl on its back. Enlarged. Compare with figure 2. TECHNICAL DESCRIPTION. THE, BEETLE. The beetle of Cotinw nitida is re- lated, although rather distantly, to the brown May or June beetles of the North, belonging to a different group of the Scarabaeidae — the Cetoniini. The appearance is quite different. It is variable as to color, but is usually a beautiful velvety Bui. 891, U. S. Dept. of Agriculture. Plate I. Green June Beetle. Eggs, highly magnified. Bui. 891, U. S. Dept. of Agriculture. Plate II. Green June Beetle. Full-grown larvce of green June beetle {Cotinis 7H7?(fa), actual size. Bui. 891. U. S. Dept. of Agriculture. Plate III. B Green June Beetle. A, pupal cell opened to show pujia within; B, pupa removed from coll, showing more details of structure. C, pupa of a white grub {Phyllopliaqa sp.). Bui. 891. U. S. Dept. of Agriculture. PLATE IV. .1 Green June Beetle. A, Pupal cells; B, same showing exit holes of beetle. About natural size. THK GREEN ,TTT"N"E BEETLE. 5 green on the dorsal surface, with the niarB CucuMEER Plants Showing Root and Stem Injury by Larv/e of Green June Beetle. Bui. 891, U. S. Dept. of Agriculture. Plate VI. Views of Parsley Field Injured by Larvae of Green June Beetle. The upper field was re-sown twice, tile lower field three limes. Bui. 891, U. S. Dept. of Agriculture. PLATE VII. Work of Larv/e of Green June Beetle on Lawn at Norfolk, Va. THE (iEEEN JUNE BEETLE. 9 injurin*^ vegetable aiul other crops. The female beetles are strongly attracted to humus, decaying plants, and manure for the deposition of their eggs, but the larvse or grubs are often dii-ectly injurious to plant life by chewing tender seedlings, stems, and rootlets, e. g., as shown in Plate V, which illustrates injury to the root and stem of cucumber. This chewing may be continued until the roots or tender stalks become partially, if not completely, severed. The principal injury, however, is due to the work of the grubs in the soil, where they cause around the growing plants an upheaval, which disturbs the root system mainly by depriving it of necessary moisture. Their constant burrowing and tunneling under the earth in fields and gar- dens also loosens the surface soil, causing it to dry out and become porous, and retards the groAvth of shallow-rooted plants in much the same manner. Where larvae as well as beetles are unusually abundant, a similar effect is produced by the perforations which they make in emerging and again in reentering the soil, (PI. VI.) Many in- stances of this nature are known and are here cited. An extreme form of injury recorded by Riley (20) is to the effect that in the case of injury to celery the heart of the plant liecame choked with soil thrown up by the larvae, and the acid excrement of the larvae induced rot. Injury to lawns and putting greens is due, in the main, to the little mounds of earth which the grubs leave on the surface of the soil, and on the grass itself. These mounds not only disfigure the lawns and greens but, in the case of the latter, which should be kept smooth, they often deflect the golf ball. Here, also, the burrowing and tun- neling, as in the case of attack to cultivated fields, cause the grass to suffer from lack of moisture. Plate VII illustrates how lawns may be disfigured by these mounds, which show plainly on the grass. INJURY BY THE GRUBS TO LAWNS AND CEREAL AND FORAGE CROPS. During September, 1902, Mr. E. M. Talcott reported injury by this grub on the golf links of the Washington Golf Club at Rosslyn, Va. The grubs were extremely abundant in that vicinity. They crawled to the surface of the ground at night, and caused injury to the grass by boring short distances just beneath the surface, throwing out small amounts of earth, and making little hummocks of sufficient size to deflect the golf balls and thereby cause considerable annoyance. October 1, 1903, Mr. F. W. Barclay, Haverford, Pa., sent mature grubs with the statement that they did very considerable damage to the greens and turf of the Merion Golf Club at that place. The grubs were present in large numbers over an area of about 50 acres, and seriously injured the turf, nearly ruining the putting greens. It could not be noticed that the grubs ate the roots of old or growing 10 BULLETIN 891, U. S. DEPARTMENT OF AGEICULTURE. grass, but if freshly cut grass Avere placed in piles, say 1 foot deep on the soil, the grubs would come up and enter into the piles within a few hours. Wasps " had learned to search for the grubs in these piles of grass. The specimens sent had been caught after they had entered new grass piles. This suggests that after the insects have been seen to enter the piles they could be killed there by hand methods. In 1904, Mr. Barclay sent, May 28, a photograph showing the actual damage done to the golf links at Haverford. June 6, Mr. Samuel P. Hinckley, Lawrence, Long Island, N. Y., stated that on his tennis grounds little hills of sand, like ant hills, were thrown up and that by running a hooked wire down into them the white grub could be pulled out. At Louisville, Ky., special work was conducted by Mr. J. J. Davis on this species. Injuries were observed and reported by him to the golf grounds of the Louisville Country Club'. Here the grubs were not directly injurious to the grass, but worked in the putting greens during the night, throwing up little hills of earth. If these were not SAvept off early in the morning they would be trampled on by the players, thus packing a thin layer of earth over the surrounding grass, killing the grass in these particular spots, and roughening the green, Avhich should be perfectly smooth. At no time were the grubs observed actually feeding on the roots of the grass, and there was no evidence of injury to the grass other than the indirect injury noted. The entire golf course was plowed and seeded in 1909, and the first occur- rence of the beetles was in 1911. Each year the ground was heavily fertilized with animal fertilizers, principally sheep manure. March 6, 1915, Mr. Wm. Buck, Waterloo, 111., described these larvae as crawling on their backs and working after sunset and during the night. He stated that they worked underground and that they ate the roots of plants The grubs worked their way to the surface and collected under pieces of manure, and in their movement upward uprooted and exposed the roots of young alfalfa plants. Their burrowing also made the soil porous and spongy, a condition which accelerates evaporation and has a damaging effect on the plants. Injury was confined entirely to the young plants, those with even a moderately developed root system not being injured. Xo evidence was found that the grubs actually gnawed the roots. October 27, 191;"), this species was observed in abundance by Mr. A. L. Chapman, Washington, D. C, who stated that grubs of this June beetle had been eating the small terminal roots of grass, chiefly Capitol lawn and crabgrass, practically ruining the entire lawn. Pre- vious attacks had been noticed, but none as severe as this. On three occasions a pint or more of the grubs was taken from the cement floor « " Control by natural agencies," p. 31. THE GREEN JUNE BEETLE. 11 of the areaway leading into the basement. The grubs were most nu- merous and active on warm, humid nights, especially after rains. The lawn was about 50 by 50 feet, raised about 4 feet from the level of the street, and was kept constantly supplied with water by two h^^drants. The grass presented a yellowish brown hue instead of a grass green, showing lack of proper nourishment. Other instances of injury to lawns and golf links have been re- ported, but Avill receive no mention here. In rearing cages the grubs cut oH young stalks of wheat, rye, cotton, sorghum, and jjaspalum grass {Paspaluin dilatatwm) but did not attack other grasses or corn which were grown in these cages. INJURY BY THE GRUBS TO VEGETABLE AND GARDEN PLANTS. Practically all cases of injury mentioned below were accompanied by living specimens of the larvae of the green June beetle. February 4, 1901, Mr. S. J. Trepess wrote that the larvae occurred in large numbers at Glen Cove, Long Island, especially where there was mulching. There were large patches in lawns where the larvjie had entirely killed the grass. He reported that four large beds of geraniums were destroyed, that they ate the epidermis off the plants at the surface of the ground, destroyed strawberry plants set out from pots in September, and attacked roots and crowns, so that every day plants were seen to wilt. Injured plants were replanted about the beginning of October on land where no trace of the insects was visible. Each plant was usually attacked by from two to six larvaj. The soil contained much humus, which our correspondent recognized as the cause of the larvae being so numerous and thriving. Mr. Trepess had been bothered with these insects in his lettuce and violet frames for two years, and had caught many of them in tomato cans sunk in the ground, the top of the can being about half an inch lower than the surface. February 5, Hon. J. H. Bromwell, Cincinnati, Ohio, sent nearly mature larvae of this species, with state- ment that it was acting like a cutworm in working around the stalks of celery and other plants and actually cutting them off close to the ground. June 11, 1904, Mr. Moritz E. Kuther, Holyoke, Mass., sent speci- mens about one-third grown, stating that they were feeding on beans, beets, lettuce, potatoes, tomatoes, carrots, dahlias, roses, and other plants, nipping the 3^oung plants just underneath the crown, and after- wards pulling the leaves into the earth. ^ The trouble was described as having begun about three years previously and attack was first confined to lettuce and beets; later they were described as attacking '' Unfortunately, a common cutworm was involved in this attack, and it is not known positively that the grubs were responsible for the entire injury. 12 BULLETIN 891, U, S. DEPARTMENT OF AGRTCULTURE. everythinre every nisht, iind silso cuts tlie roots of geraniums and otlier flowers. January 11, 1913, Mr. E. B. Cantrell, Winston-Salem, N. C, re- ported that the grubs were very abundant in his garden; so much so as to interfere with the growth of the plants. The two years pre- vious Mr. Cantrell used stable manure freely on his garden and, as he surmised, this was doubtless responsible for the appearance of the grubs in such numbers. Writing March 18, Mr. Cantrell said : I have observed the grubs for a number of years and have never known them to occur on any kind of land or injure any kind of crops excepting where stable or lot manure had been used. Therefore their greatest numbers are to be found in gardens. The grubs breed and thrive on manure and almost any crops planted there. Especially in dry weather there is damage by them as they plow up and make holes that cause plants to suffer for moisture. Sometimes plants ai*e cut off, tomatoes on the ground eaten, and especially have they in- .lured my celery. May 17, 191-1, Mr. Edward T. Knight, Bureau of Plant Industry, reported injury by this grub to iris, which had been a source of complaint about a year before. October 24, 1914, Mr. C. F. Turner, Bureau of Entomology, found the grubs doing considerable damage in the gardens belonging to Mr. L. G. Buckner at Memphis, Tenn. Corn, potatoes, turnips, and eggplant were said to be attacked. Mr. Buckner wrote Novem- ber 5, 1914 : The grubs in our garden keep the ground near the surface pulverized. A rain, of course, packs the ground and in a day or two the ground is again pulverized. We are not sure that the plants died because the roots were eaten or whether it was the continuous working under and around them. They did not bother the plants on top of the ground. We had a very fine patch of turnips and they killed nearly all of them. They also ruined tomato vines and English peas. They attacked fall potatoes, not killing the vines, but I know they ate some of the potatoes ; however, not a great deal. Our garden has been well fertilized with stable manure. During the same month Prof. James Troop, entomologist at Purdue Experiment Station, received specimens from a correspond- ent at Bedford, Ind., who reported that the larvae damaged endive. The correspondent wrote October 27, 1914, as follows : The endive I have covered with a board to bleach. Frequently when I would lift a board off of the endive I would see the worm disappearing in the hole out of which his head had been protruding, and quite often they would in this manner eat a third and often half of the bunch of endives. The correspondent had adopted two methods for bleaching the endive — laying boards over the plants and bunching and tying up the heads — but the grubs attacked only that under the boards. 14 BULLETIISr 8&1, U. S. DEPARTMENT OF AGRICULTURE. December IT, 1914, Mr. A. Patterson, Ensley, Ala., wrote that these " grub worms " keep the soil in the garden very loose, especially around the roots of collards and turnips. They were unevenly dis- tributed in the garden, in 5 or 6 foot areas in holes 4 or 5 inches apart. The surface of parsnips was eaten off in places, some eroded areas extending completely around the root and stopping its growth. Mr. Thomas H. Jones, Bureau of Entomology, has contributed the following notes, based on specimens : November 22, 1915, Mr. J. O. Bethes, Franklinton, La., wrote in substance : This grub was taken from a garden here where the species is doing a great deal of damage. In the daytime the worm penetrates the earth to a depth of about a foot and at night comes to the surface and works up the ground in the manner of a mole. It is doing damage to turnips, cabbage, and other plants growing in the gardens this season of the year. December 28, 1916, Mr. Jones observed the larvae in water in a ditch at the Louisiana State University, Baton Rouge, La. Although they were motionless when removed they soon became active when brought into the office. They had eyidently bred on the parade grounds on the other side of a walk separating the groimds from the campus, since the beetles had been observed in large numbers in late summer. Numerous trails were found in the wet dirt, and there were holes and piles of freshly worked-over dirt in the grassland. The heavy rains caused the grubs to come to the surface. Prof. O. W. Rosewall had previously seen the grubs above the surface at night after heavy rains. March 16, 1917, Mr. W. J. Sutcliff, Monroe, La., wrote: A while back these grubs were in the garden by the millions, and yesterday a number were found dead. They, or some other insect, literally plowed the very top of the ground up, and by doing so they killed the little plants coming up. Digging down below the surface of the groimd for three or four inches, the ground is perforated with holes resembling on a small scale those made by crayfish. October 28, 1918, Mrs. A. M. Kistler. Morganton, N. C, sent speci- mens of larvae with the statement that she could furnish them by the bushel, and that they were infesting her garden and hotbed. They were described as destroying everything in the garden — cabbage, turnips, salsify, lettuce, radishes, peppers, tomatoes, and celery. Paris green was tried without effect, and kerosene emulsion was advised. November 13, 1919, Mr. C. S. Stewart, Baton Rouge, La., reported the grubs of this species in his garden. He wrote: For the past six years my fall garden has been ruined almost entirely from this cause. It is a grub that grows about 1 inch long, comes to the surface during the night, runs on its back, eats almost eveiything green, and to give you an idea of tJieir numbers I will say that I have picked up as many as 1,000 in a single night. Where they work and crawl the surface of the ground THE GREEN JUNE BEETLE. " 15 looks as if it had been raked. I use stable manurf, but within two years liave limed the soil. Right now I am plowing out my grub crop, turn the soil, pick up, and throw to tlu' chickens. I haven't anything in my garden this fall except grub worms. INJURY BY THE GRUBS IN A GREENHOUSE. A single instance of injury by the grubs of this species in green- houses was reported in November. 1898. Mr. W. E. Pray, Kinkora, N. J., reported injury in his violet houses (31). The larvae were first noticed soon after the plants had been put in the bed, and at this time they seemed to do little if any harm, but the ground was described as being *" kept wvU cultiAated for 2 inches deep b}' their movements.'" As the plants grew, t!ie larv;e, it is stated, began to feed upon the fibrous roots, and Avere so doing at the time of writing. They were e reached. In this connci'tum it sliould be notrd that the grubs are frequently brought into greenhouses Avith manure, and as a consequence of the superheated indoor atmos]:)here the beetles issue practically^ through- out the winter, as has happened at iVorfolk, Va,, and at Washing- ton, D. C. INJURY BY THE BEETLES. Attention has been draAvn to the injurious attack of the beetles to fruits. Of these, the thin-skinned fruits, especially figs, peaches, and grapes, are most often damaged, other fruits which have been listed being occasionally or slightly attacked. Injury to figs in South Carolina, Georgia, and other southern States is an annual oc- currence, and indeed one of the popular names of this beetle is " fig- eater.'' From Pennsylvania southAvard come frequent reports of injury to peaches, often to those which are quite sound, contrary to the opinion of some authors that only decaying, partially decayed, or overripe fruit is attacked. The green June beetle is a A^ery well- knoAvn grape pest, and Prof. H. Garman (32) reported injuries to this fruit in Kentucky as foUoAvs : The common green June bug, well known to every Kentucky school boy, be- comes very troublesome locally and occasionally by cutting the skins of grapes and utterly destroying the fruit of Avhole bunches and even whole vines. On the experiment farm at Lexington this pest would, if allowed to work unhin- dered, destroy the whole crop of the early A'arieties in the experimental vine- yard. It was formerly more troublesome than uoav, but is liable any season 16 BULLETIN 891, U. S. DEPARTMENT OF AGRICULTURE. to appear in such numbers as to be the cause of anxiety on the part of those liaving the vineyard in charge. The very sweet, tliin skinned, early sorts suffer most severely. On a visit to the vineyard, August 1, 1896, I found Moore's Early, Poughkeepsie, and White Imperial being severely damaged, while Bril- liant was only moderately injured. The clumsy beetles were clinging to the berries, in some cases a dozen on a bunch, greedily devouring the pulp and leav- ing them in an unsightly and utterly ruined condition. They were guilty dur- ing the same month of injury ro early peaches and plums. Webster and Mally (27) have reported injury by the beetles to tomatoes in southern Ohio, and state that melons are sometimes eaten; corn in the ear is a favorite food, and not infrequently the beetles are sufficiently numerous to injure noticeably both field and sweet corn. They have even been observed injuring young corn plants by gnawing into the stalk, and in one instance young sor- ghum plants were attacked. The beetles are also f requentl}^ complained of as a nuisance in well- kept lawns and golf greens, because of the little mounds of earth excavated by them as they enter the ground, but they are by no means as troublesome in this respect as are the larvae. In 1909 Mr. R. A. Vickery, Bureau of Entomology, observed the beetles at Salisbury, N. C, August 10, feeding on kernels of corn near the tip of the ear, the injury having first been started by the related Euphoria sepulchralis Fab. At Wellington, Kans., Messrs. E. 0. G. Kelley and T. H. Parks, Bureau of Entomology, observed beetles feeding on young stalks of corn July 19, They were boring large holes near the base of the stalk between the second and third joints. Mr. Kelley repeated this observation and later, August 10, 1911, found them feeding on corn kernels. July 14 of the same year Mr. G. G. Ainslie, Bureau of Entomology, observed the beetles feeding on sweet-corn kernels at Nashville, Tenn. At the same locality Mr. W. H. Larrimer, Bureau of Entomology, reported injury to sorghum July 21, 1913. The beetles were ob- served in the " throat " of the plants, evidently having been attracted by the honeydew of the corn leaf-aphis,® or by the sweet sap of the sorghum itself. This attack caused the leaves to split at the base, injuring the plants to quite an extent. When the field was revisited a week later the beetles had disappeared, and while the plants were attempting to outgrow the injury, the damaged ones were easily distinguished. July 9, 1915, adults were observed at Ocean View, Va., flying over lawns and hedges and floAver beds, those captured proving to be largely females. Later in the month they w^ere also observed at Portsmouth, Va. The parasitic sarcophagid flies were observed on hedges, and in all probability thus able to deposit their larvae on the adults of C. nitida, resting on the hedges. ^ Aphis maidis Fitch. THE GREEN JUNE BEETLE. 17 June 29, 1016, a sin«;le adult was captured at Norfolk, Va. B}'^ July 10 numbers were observed flying around hedges and lawns. By August 8 the beetles w^ere observed at Portsmouth, Va., in large numbers. They disappeared about September 20. In 191C Mr. J. E. L. Lauderdale observed adults at Baton Rouge, La., feeding on the juices of corn. They were observed between July 8 and Septem- ber 19, none being found after September 22, occurring in greatest numbers in August. On August 4 Mr. F. B. Milliken, Bureau of Entomology, observed the beetles at Wichita, Kans., feeding on egg- plant in the early morning, maldng large ragged cavities in the sides of the main stems or branches. During the next five years, up to 1922, few complaints of injury were received aside from the normal number to lawns and golf links, these emanating from Maryland, Virginia, District of Columbia, southern Pennsylvania, and New York. Injury to celery and en- dive, resulting in a loss of more than 40 per cent of the crop which might have been due to this insect, was reported at Sunbury, Pa., but without specimens. Complaints of injury in gardens were re- ceived from Louisiana in 1919, one correspondent at Amite stating that for six years his garden had been almost ruined from this cause. Beetles Entering Beehives. During July, 1903, the senior author's attention was called to great numbers of dead beetles of Colin is tiifida, found under the entrances to beehives on the grounds of the Department of Agricul- ture, where the living beetles were quite a nuisance. There were considerable numbers of them endeavoring to obtain entrance to the hives, and they occupied the attention of a number of the bees that were as intent on preA'enting their entrance as the beetles were on getting into the hives. On account of the hard exterior coating of this insect the bees' stings did not appear to penetrate until perhaps after a great many attempts. The beetles were per- sistent, but very slow and sluggish, and under the circumstances it can readily be imagined that an appreciable amount of honey that might have been produced was lost through the distraction of the attention of the bees to the intruders. The beetles appeared to be utterly unaware of their danger and as stupid as the Scarabaeidae are generally accredited with being, at least when not in flight. LIFE HISTORY AND HABITS. In the vicinity of Norfolk, Va., the beetles make their first appear- ance about the middle of June, reaching their height in numbers by the middle of July and continuing numerous until the middle of August, disappearing about the first week in September, 186606°— 22— Bull. 891 2 18 BULLETIN 891, U. S. DEPARTMENT OF AGEICULTUEF. Throughout a period of from 4 to 6 weeks the beetles occur abundantly, beino; most active late in the afternoon, when they fly either close to the ground or soar high among the tree tops. When they alight on trees serious injury sometimes results from the beetles gnawing into the young twigs, causing the latter to break off. The beetles are also attracted to ripe fruit and gather by dozens on ripe melons, tomatoes, and green corn. Mating occurs during periods of rest, when the beetles alight on tree tops, shrubbery, fences, or on lawns and grassy places, the fe- males attracting the males — sometimes many males attending one female. Before oviposition the females, buzzing like bees, fly close to the ground and select a place to enter the soil. After alighting they disappear rapidly from the surface and remain in the ground for two days at a time, sometimes coming to the surface to feed and again disappearing. EGG LAYING. The soil condition that attracts the parent beetles for egg laying is land originally sandy, subsequently richly incorporated with humus or organic matter, either in the form of well-rotted manure or decomposing vegetation. Such are the field conditions of the two principal infested localities in the vicinity of Norfolk, Va., where the green June beetle occurs in abundance. This gives a soft, warm, mellow soil, rich in organic food, retaining moisture, yet never soggy or cold during the egg-laying period, and affords easy access for the beetles to enter and deposit eggs. The conditions are ideal for incubation and the subsequent work of the larvae. Cage experi- ments demonstrated that a pure sandy soil does not attract the beetles to oviposit, but when well-rotted manure is added in about equal portions the beetles readily deposit their eggs.® The reported finding of larvse in dung has often raised the ques- tion as to whether eggs are deposited in manure. There are instances on record where larvae have been so found, and the larvae have received the local name of " dung grubs." Mr. F. Richardson, of Portsmouth, Va.. states that about 1908, when he first began haiding cow manure on his farm, he often noticed that hardened or caked pieces of dung when broken revealed the presence of numerous "grub worms," of what he supposed to be this insect. Several years after the use of this manure his place became noticeably infested with the grubs, so that he finally discontinued the use of this manure and supplanted it with stable manure. During the height of their season the beetles were often observed entering and issuing from the soil in the process of » The beetles were induced to lay in pure sand, altlioush reluctantly, and with much effort on the part of the female to escape confinement and to search through the sand for a suitable spot for deposition. THE GREEN JUNE BEETLE. 19 efjo:-laying. This matter of the dim: linbii will be discussed further under the heading; "History and literature," p. 28. Period oi- Incubation. The period of incubation in the field, as will readily l)e understood, depends in a larjje measure on climatic conditions for that period, and moisture particularly plays a part in the development of the em- bryonic larva. This fact has been illustrated with e^^s kept in the laboratory in vials. It was determined that the i}