^^^"^^^^ X"^^^ ^^^P"/* \ ^ " \ ^^^^\ ^^^^\ /.^^^ ^ ^ '^, ISSsilS ^" '%. \i.afiCf ^ ' % ^^^ sf ^ WUSW . •- ^ \;rowin^- season, which i)ermits mor(» . — C.odlin-iiioUi Hither thin, but cpilte toUJ!;h, and is inndv. lurv.-i in its coroon on a lar^-ely of silk in which are mixed bits of •'-"•k-Hako (x2). ni.'ide. II is lined with whit(; the subst.'ii) which il i,^ Fk.-O. — (:.> make the first spraying for the codlin-nioth. b(^ carefully protcucted. During the winter they feed in small flocks, going over the samc^ territory day after day, carefully examining (^v(^ry i^ortion of the bark for insect food. They may \)c inchiced io visit an orchard regularly by tying stri])s of l)eef fat to a few of the branches and the destruction of codlin-moth larva^ will more than i)ay for the trouble involved. Means of control. When single brooded or when the second generation is only partial, the codlin-moth has not been found a very difficult APPLE INSECTS 19 pest to control by si)rayinj>; witli an arsenical poison. In the South and ])()rtions of tlu^ West, however, where two or more full generations develo]), sprayinj*; has in <>;eneral «;iven less satisfactory results. In sprayin<>,- for this insect a; apple stands upri«;ht on the stem Fit;. 17. — Two later stages, the calyx lo])es closed ; it is now too late to si)ray ei'fectively. with the calyx end directed ui)ward (Fig. !())• If at this time an arsenical spray is thoroughly aj^plied with sufficient force to drive the poison into the calyx cu]), minute i)articles of the poison will be deposited where the young larva will get it in his first meal as it centers the fruit. In about two weeks the calyx lol)es close as shown in Figure 17, and it is then too late to spray effectively, for it is then impossii)le to place th(^ poison where it will do the most good. The closed calyx lobes form 20 FRUIT INSECTS a tight roof over the cavity and prevent the rain from washing away the poison. To be most effective this first spray should be appHed as soon as possible after the larger part of the petals have fallen. Great care should be taken to hit each apple, the spray should be directed downward directly into the blossom end of the fruit and sufficient power should })e used to give a strong spray. In commercial orchards the best results are obtained where a good power sj^rayer is used and where the nozzle, on the end of a light extension rod, is handled by a man standing on an elevated platform or tower. In the Eastern states a fine, mist-like spray is most commonly used, but in the Far West remarkable results have been obtained by the use of a coarse driving spray, such as is produced by the Bor- deaux nozzle. Not all the larvae are killed in the calyx cavity, for quite a number always enter the fruit at some other point. A large part of these are killed by the poison on the leaves where many of them feed slightly before reaching the fruit, while others are doubtless destroyed by the poison adhering to the surface of the apple, although the number killed in this way is not large. This first spraying immediately after the petals fall is the most important operation in the fight against the codlin-moth, and no pains should be spared to make it as effective as possible. Not only does it control the injury by the first brood larvae, but it also prevents in large measure the losses occasioned by the later broods. In the Far West, where two full broods develop, some remarkable results have been obtained from this spraying alone when the application was made with great thoroughness, using a coarse driving spray and suflficient pressure to place the poison deep in the calyx cavity. In some cases as high as 95 or 99 per cent of the crop has been protected in this way without the necessity for any later spraying. Attempts to control the codlin-moth in the East by the one-spray method have not as yet shown it to be superior to the more common APPLE INSECTS 21 practice under Eastern conditions, where it is necessary to make repeated applications of a fungicide for the control of apple scab and other fungous diseases, but they have called attention to the great importance of doing very thorough work with the first spray. At the time the first spraying is made the codlin-moth eggs have not yet been laid and the majority do not hatch until about 3 or 4 weeks later. If about the time of hatching the foliage and fruit are thoroughly coated with a fine arsenical spray, many of the newly hatched larvae will be killed before reaching the apple, since many of the eggs are laid at some distance from the fruit and the larvae feed to some extent on the leaves. In case the first spraying, because of carelessness or for some other reason, has not controlled the worms, it may be advisable to spray for the second brood. This spraying should be done just as the majority of the eggs are hatching. The proper time may be determined by banding a few trees with burlap bands. When empty cocoons are found beneath them it shows that the moths are emerging. Eggs will be hatching in about a week or two. In New York the second brood larvae enter the fruit in late July and in August, but the exact time varies greatly with the season. The larvae of the later broods are much more numerous than those of the first and the loss which they inflict is correspond- ingly greater. Where the first spraying has been neglected one cannot hope to protect his crop by spraying for the second brood alone. But where the first brood has been reduced to a minimum by a thorough early spraying much good can oftentimes be accomplished by a later spraying to destroy the progeny of the few stragglers missed earlier in the season. Paris green has been for years the standard poison used against the codlin-moth, but it has now been almost entirely replaced by arsenate of lead. The latter has, on the whole, 22 FRUIT INSECTS given better results. It sticks better to the foliage and fruit, contains practically no free arsenic and may be coml^ined with the dilute lime-sulfur, as used for the apple scab. One pound of Paris green or 4 to 6 pounds of arsenate of lead in 100 gallons of water has, in general, given the best results. Paris green or arsenate of lead may be combined with Bordeaux mixture and arsenate of lead with lime-sulfur, but Paris green has proved injurious to the foliage when used with the latter. Success in controlling the codlin-moth does not depend so much on the kind of poison used as on the thoroughness and timeliness of the application. The personal factor is of the greatest importance. At picking time many infested apples are carried to the packing shed or storehouse, where the larva) emergen and spin up in cracks and crevices. In case the storehouse is near the orchard the windows should be screened to prevent the escape of the moths the following spring. Before the discovery of the arsenical method of controlling the codlin-moth banding the trunks with strips of burlap was widely practiced. These bands arc; put around the trunk and larger l)ranches, and beneath them a large proportion of the larvae will spin their cocoons. They should h^ examined and the larvae killed regularly every week during the cocooning season. It is generally believed that in properly sprayed orchards the use of bands will not pay for the trouble and expense involved. Heferences Howard, Kept. U. S. Dopt. Agr. for 1887, pp. 88-115. Cornell Agr. Exp. Sta. Bull. 142. 1898. Extensive bibliography. U. S. Bur. Ent. Bull. 41. 1903. Utah Agr. Exp. Sta. Bull. 87. 1904. Utah Agr. Exp. Sta. Bull. 95. 1906. Wash. Agr. Exp. Sta. Bull. 77. 190(3. N. M. Agr. Exp. Sta. Bull. 65. 1907. 111. Agr. Exp. Sta. Bull. 114. 1907. APPLE INSECTS 23 Quaintance, Year Book U. S. Dept. Agr. for 1907, pp. 435-450. 1908. N. H. Agr. P]xp. Sta., 19th and 20tli Rept., pp. 896-498. 1908. U. S. Bur. Ent. Bull. 80, Pt. I. 1909. Mo. State Fruit Exp. Sta. Bull. 21. 1909. Ga. State Bd. Ent. Bull. 29. 1909. Felt, 25tli Rept. N. Y. St. Ent. pp. 25-71. 1910. Extensive hihliocj- raphy. U. S. Bur. Ent. Bull. 80, Pt. V. 1910. U. S. Bur. Knt. Bull. 80, Pt. VI. 1910. Ont. Dept. Agr. Bull. 187. 1911. Wash. Agr. Exp. Sta. Bull. 103. 1911. U. S. Bur. Ent. Bull. 97, Pt. II. 1911. Felt, Jour. Ec. Ent. V, pp. 153-159. 1912. U. S. Bur. Ent. Bull. 115, Pts. I, II. 1912. The Lesser Apple Worm Enarinonia prunivora Wills li This insect is closely related to the codlin-moth, and both in its life history and the nature of its injury to the apple is very similar to that insect. Originally described ])y Walsh in 1867 as a plum pest, it has more recently shown itself a serious enemy of the apple in cer- tain localities. It is generally distributed throughout the East- ern states from Texas and Georgia north- ward to Ontario and Quebec and also oc- curs in British Co- lumbia. The full-grown T/'V '^" ~ " motli larva ; larvie are about § worm(xo), - Upper figure, partly srowii codliii- lower two, larva) of the lesser apple 24 FRUIT INSECTS inch in length, and pinkish or nearly white in color (Fig. 18). They leave the fruit in the fall a little later than the codlin-moth larvae and spin cocoons in similar situations ; occasionally pu- pation occurs within the apple itself (Fig. 20). The larva may be distin- guished from that of the codlin-moth by its smaller size, and by having a brownish, comb-like structure on the caudal curvature of the anal plate visible only under a Fig. 19. — Cocoon of the . i lesser apple worm with SXrong lens. empty pupa skin protrud- The CO- ing (x 7). c o o n 1 s about J inch long, lined with white silk and covered on the outside with bits of bark and dirt (Fig. 19). The following spring the larva changes to a brownish pupa less than J inch in length. The dorsal surface is armed with transverse rows of short spines by which the pupa works itself part way out of the cocoon before the emergence of the moth. The empty pupa case is usually left attached to the cocoon. The moth (Fig. 21) measures about yV inch across the expanded wings. The front wings have the gen- eral appearance of watered silk when viewed with the un- aided eye. The gen- eral color is a warm brown, darker on the Fk;. 20. — Empty pupa skin of lesser worm protruding from end of small apple. Fiti. 21. Lesser apple worm moth (X 5). APPLE INSECTS 25 front margin and at the tip and lightc^r towards the ])ase. Under a lens it is secni that this eff(H't is pro(hiced by groups of scales of three shades of })rown; reddish, chocolate and light l)rown ; in addition th(^ wing is crossed by three fine in- terrupted irregular pearl-l)lu(i lines, th(^ basal on(i being double in front. The hind wings an^ brown, paler towards the base. The moths emerge and e^ggs are laid at al)out the same time as those of the codlin- moth. The eggs are glistening milk y white, fiat and scale- like, and closely re- semble those of th(} codlin-moth, l)ut are |MH||^ • « only a little more than one half as large. They hatch in 5 or 6 days. The injury caused by this insect has often been confused with the work of the codlin-moth. Many Fig. 22. — Work of lesser apple worm at the P , 1 1 blossom end of a mature apple. 01 the young larvae enter the fruit through the calyx cavity, while others bore through the skin just outside the calyx, and still others enter at the side and near the stem. A larger proportion of the first brood enter at the calyx than is the case with the second genera- tion. In general, the burrows are not so deep as those of the codlin-moth. The larva remains near the surface and eats out a blotched mine just beneath the skin which turns whitish and greatly disfigures the fruit (Fig. 22). In the North there are two generations annually ; in the Ozark region there are three and sometimes a partial fourth brood. 26 FRUIT INSECTS Many of the first brood larvae pupate in the fruit and the empty pupa case is frequently found protruding from the burrow. Apples infested by small larvae are frequently placed in storage where they continue to feed and often cause considerable loss. The lesser apple worm moth has also been reared from plum, from black-knot, a fungous swelling on plum branches, and from certain insect galls on ehu and oak. Remedial ineasures. The treatment suggested for this insect is the same as that for the codlin-moth, except that there is especial need of mak- ing the second spraying, 3 to 4 weeks after the petals fall, very thorough. To kill the young larv« entering at the stem and side at that time the foHage and fruit siiould l)e tlioroughly coated with a fine arsenical sj)ray. References U. S. Bur. Ent. Bull. 68, Pt. V. 1908. Taylor, Jour. Ec. Ent., II, pp. 237-239. 1909. U. S. Bur. Ent. Bull. 80, Pt. III. 1909. Apple Fruit-miner Argyresthia conjugella Zeller The larva of this small Tineid moth is a serious pest in the apple orchards of western Canada. It also occurs in northern Europe, where it frequently destroys the entire apple crop. In Europe it originally fed on the berries of the Mountain Ash and in Canada on the fruit of the Wild Crab (Pyrus fusca) but it has now become thoroughly established on the culti- vated apple. In England and Scandinavia it has been found infesting the cherry. The injury is caused by the pinkish white larva, about | inch in length, which burrows in all directions through the fruit during July, August and September. The tissue around APPLE INSECTS 27 the l)urrows turns brown, decay ensues and the apple is ruined. Tlie parent moth (Fig. 23) has a spread of nearly J inch ; the front wings are iridescent purplish gray mottled with brownish ; on the front margin is a row of minute white and brown dots and a larger oblique white mark occurs near the apex ; on the hind margin is a broad creamy-white band interrupted near the middle by a brownish spot. The moths appear in May and June. The eggs are unknown. The young larvse enter the fruit at the side and on becoming full-grown leave the apple and seek shelter under the bark on the trunk or under leaves on the ground. The winter is passed Fig. 23. The apple fruit-miner moth (X 7.j). in the pupal state in white cocoons, the outer layers of which ar(; loose and have the threads arranged so as to form a beautiful openwork pattern. Remedial measures. Satisfactory methods of control have not yet been devised, but several thorough sprayings with arsenate of lead, so applied as to keep the fruit coatc^l with the poison, would doubtless do much to lessen the injury. References Kept. Exp. Farms Ottawa 1896, pp. 258-262, 1897. Kept. Exp. Farms Ottawa 1897, pp. 201-202, 1898. Reh, Prakt. Ratg. Obst- und Gartenbau, XXII, pp. 452, 453. 1907. 28 FRUIT INSECTS The Apple Red Bugs Heterocordylus malinus Reuter, and Lygidea mendax Reuter These two native sucking plant-bugs have in recent years caused considerable injury in certain orchards in New York and New Jersey by puncturing theyoung apples during May and early June. Many of the punc- tured apples fall to the ground, others dry up on the tree, while the remainder mature but are badly deformed and ren- dered unmarketable (Figs. 24 and 25). Red bug injury may be distinguished from 1 '»>g the work of the plum curculio ])y the fact insecl does not, n^move any of the Fig. 24 Mature apple defon puneturrs. that in making the puuclui-c It tissue, but merely sucks out tlie juices. When al)undaut the apple aphis fre- q u e n 1 1 y causes knotty and mis- shapen apples, but its work is usually characterized by a t^, or v i i,- u j j ^ i ^ l^iG. 25. — \ oung apples which dropped prematurely stunting or pucker- as a result of red bug injury. APPLE TX SECTS 29 Fig. 2( Red bug nymph feeding on a newly set apple. Much enlarged. ing of the blossom end which is not present in typical red bug injury. The life histories of the two species are very similar. The dull whitish, strongly curved, slightly compressed eggs are inserted their full length into the bark on the smaller branches (Figs. 27 and 28). They hatch soon after the opening of the leaves of the fruit buds and the minute, tomato-red nymphs at once begin to puncture the tender leaves. The clusters of fmji.*v«fc .* minute reddish dots ' ^ g Vf ^ caused by these punc- tures are quite conspicu- ous and are usually the first indication of the presence of the nymphs. The injury to the foliage is very slight. They may feed on the leaves until full grown but usu- ally attack the fruit as soon as it sets (Fig. 26). In the case of very small apples, the four sharp bristles of the beak penetrate quite to the center, the surrounding tissue becomes discolored and hardened and the apple is ruined. Fig. 27. — Eggs of H. ma- liniis inserted in a slit in the bark at the base of a fruit spur. Fig. 28. — Eggs of L. mendax in len- ticels on a two -year -old apple branch. 30 FRUIT INSECTS Fig. 29. - Fifth stage nymph of //. malinus (X 9) . The young nymphs of the two species are very similar. Those of L. mendax may be distinguished by their brighter red color, the absence of dusky markings on the thorax and ])y having the body clothed with fine short l)lack hairs. Both species pass through five im- mature stages and attain wings at the fifth molt (Figs. 29 and 30). The adults of both species are a])out } inch in length. In H. malinus (Fig. 31) the general color varies from red to nearly black and the entire dorsal sur- face is sparsely clothed with conspicuous white, flattened, scale- like hairs. In L. mendax (Fig. 32) the general color is lighter and these hairs are lacking. As far as we have ob- served Greenings, Pound Sweets and Spies, in the order named, are the varieties most subject to attack. Sometimes the whole crop is rendered unmarketable, but such severe injury is unusual. Remedial ineasicres. It has been found im- practicable to attempt to destroy either the eggs or p^^^_ 3^^ _ ^.^^^^ ^^^^^ ^^^^^^ ^^ ^_ the adults. The former mendax (X 9). APPLE INSECTS 31 are inserted in the bark where the embryo develops some distance from the surfaces ; the latter are relatively few and oeciir when the; trees are in full foliage, when it would Ix^ very difficult to hit them. Attempts to destroy the young nyinphs by spraying with kerosene emul- sion or whale-oil soap have not l)een suc- cessful, l)ut fairly good results have been obtained by the use of ''Black Leaf 40" tobacco extract, one pint in 100 gallons of water, applied very thoroughly just before the blossoms open. Sometimes a second apphcation, just after the falling of the petals, may be found necessary. " Black Leaf 40 " can be used with the lime-sulfur as used for a summer spray. When used wuth water add 4 to 5 pounds of soap to make the mixture stick and spread better. The spraying should be done on bright warm days, for in cool weather many of the nymphs hide away in the opening leaves. Reference Cornell Agr. Exp. Sta. Bull. 29L lOU. P'iG. 31. — ■ H. ma linus, adult (X 3|). Fi( . 32. — L. mendax, adult (X3|). The Apple Maggot Rhagoletis pomonella Walsh This native American insect, although originally feeding in the fruit of the w41d thorn, has during the past sixty years be- come a serious enemy of the apple in the Eastern states and 32 FRUIT INSECTS Fig. 33. — FuU-growi) apple maggot, side view ( X 7). Canada. While summer and early fall varieties are particularly subject to attack, winter apples are also sometimes badly in- fested. Sweet and subacid varieties are most susceptible, but such acid varieties as Greening, Baldwin and Oldenburg are sometimes attacked. In the Lake Cham- plain region the Fameuse is very subject to injury, and in western New York and Canada crab apples are sometimes badly infested. The inj ury is caused by a whitish maggot, J inch or more in length, which bur- rows in all directions through the fruit (Figs. 33 and 34). In the Northern states, the parent flies appear in early July and continue abundant well into September. The females do not begin egg-laying till two or three weeks after emergence. During this time they may be seen resting on the leaves or fruit and lapping up drops of moisture, or licking the surface of the waxy covering of the Fig. 35. — Apple maggot fly (x 4f). fj.^^^ ^^j^h their fleshy proboscis. They are blackish, two-winged flies with the head and legs yellowish ; the abdomen has three or four transverse white Fig. 34. — Full-grown apple maggot, ventral view. APPLE INSECTS 33 Fig. 36. — Apple maggot pu- paria (X 7). bands and the wings are crossed by four dark confluent bands (Fig. 35). They are sUghtly smaller than the house fly, which they closely resemble in shape (Fig. 37). The female is pro- vided with a sharp ovipositor with which she punctures the skin of the apple, usually on the side, and in- serts her minute, whitish, elongate egg directly into the pulp. The eggs hatch in from two to six days. On hatching the young maggots start their tunnels through the flesh but grow very slowly until the fruit be- gins to ripen or soften from decay (Fig. 38). When this occurs the maggots grow rapidly, and by their winding burrows soon reduce the interior to a brownish, sponge-like mass. It frequently happens that at picking time the fruit may show no signs of ....i-Mi^mmr-s^. infestation, only to go down sud- denly from maggot attack after having softened in storage or in transit. This is very likely to happen in the case of Fameuse and Mackintosh when grown in infested localities. Sometimes the burrows run for some dis- tance just beneath the skin, showing through as darkened trails, from which tlu^ insect has received, in some localities, the name of railroad worm. When full-grown, the larva escapes through a ragged opening in the skin of the fruit, usually after it has fallen, and then as a rule burrows an inch or so into the soil, where it hibernates in a brownish puparium (Fig. 36), .4 Fig. 37. — Ai)ple maggot fly resting on an apple (X 2). S4 FRUIT INSECTS which has been aptly Hkened to a grain of wheat. In New York, at least, there is a partial second brood of flies appearing in September. Remedial measures. As the eggs are inserted directly into the pulp beneath the skin of the fruit, and as the maggots never leave the apple until full-grown, it is impossible to kill them Vm. ."is. — Apples infested with apple maggot beginning to decay. with any poison or contact spray. The flies, however, can be readily destroyed by having the fruit and leaves covered with an arsenate of lead spray at the time of their emergence in early July. As stated above, the flies do not begin oviposition until three or four weeks after emergence ; during this time they feed considerably on the waxy covering of the fruit and lap up drops of moisture from the fruit and foliage. Experiments in New York have shown that if the trees are sprayed the first week in APPLE INSECTS 35 July with arsenate of lead, 4 pounds in 100 gallons of water, most of the flies will be killed. It has been suggested that the addi- tion of molasses or sirup to the poison spray would make it more attractive to the flies, but the experience of the majority of commercial growers indicates that this is unnecessary. When orchards are well cultivated, so as to give a minimum of pro- tection to the puparia through the winter, and when a good sys- tem of spraying is practiced, the apple maggot is not troublesome. It is probable that under these conditions most of the flies are killed by the arsenate of lead used for the control of the codlin- moth. References Maine Agr. Exp. Sta., Ann. Rept., 1889, pp. 190-241. Maine Agr. Exp. Sta. Bull. 109. 1904. R. I. Agr. Exp. Sta., Ann. Rept., 1904, pp. 191-201. U. S. Bur. Ent. Circ. 101, 1908. Cornell Agr. Exp. Sta. Bull. 324. 1912. The Apple Curculio Anthonomus quadrigibhus Say Apples are subject to attack by three species of weevils which are, in the order of their importance, the plum curculio, the apple curculio and the apple weevil. The first will be discussed in detail under plum insects (page 243). The apple curculio is generally distributed over the Eastern states and Canada, where it breeds abundantly in wild crab and thorn apples. As an apple pest its work has often been confused with that of the plum curculio, for the two species usually work together and deform the fruit in a similar manner. It has come into prominence principally in Missouri and southern Illinois, and as a rule only in connection with destruc- tive outbreaks of the plum curculio. Conditions favoring the presence of the one seem also to favor the abundance of the 36 FRUIT INSECTS other. Usually the apple curculios are greatly in the minority, and their presence serves merely to supplement the injuries inflicted by the other species. In Connecticut this species has been recorded as seriously injuring young peach trees })y punc- turing the twigs. The apple curculio is a reddish-brown snout l)eetle, and may be distinguished from its relatives by having four distinct humps on the posterior declivity of the wing covers, two on each side (Fig. 39). The thorax is usually striped with three ash-gray lines and th(^ front part of the wing covers are more or less grayish. The femah^ is about J inch in length, the male a little smaller. The beak is over one half the length of the body in the female, is slightly curved downward and carried projecting obliquely forward and does not hang down like an elephant's trunk as in the Fig. 39. — The apple curculio ( X 4). Pl^m CUrculio. The beetles hibernate in grass, under rubbish and in other sheltered places, and ap- pear on the trees soon after the petals fall. They begin to feed on the young apples as soon as they are as large as small peas, and the female begins egg-laying soon after. In feeding the beetle punctures the skin of the apple b}-- means of the small jaws at the tip of the beak and then eats out a cylindrical cavity in the pulp as deep as the length of the beak. Growth is stopped around the i:)uncture, the surround- ing tissue hardens and a knotty deformity results. The cavity excavated by the female for the reception of the egg is similar to the one made in feeding but is considerably enlarged at the bottom. After placing the oval white or yellow- ish egg, 2V inch in length, at the bottom of the cavity the female seals up the small external opening with a drop of excrement. APPLE INSECTS 37 In feeding and in excavating the egg-cavity very little of the skin is swallowed ; it is merely torn back out of the way. This is one reason why it is so ilifficult to kill the beetles with an arsenical spray. In southern Illinois oviposition extends from late May to about the middle of July, and the average number of eggs laid by each female is about 65. The eggs hatch in four or five days and the larva feeds on the pulp, becoming full-grown in about 20 days. When full-grown it is nearly one half inch in length, footless, and owing to the enlargement of certain seg- ments on the back is so strongly curved that it is unable to straighten out. It pupates within the cavity in which it has fed and in about one week the beetle emerges. The new brood of beetles, unlike the plum curculio, feed very little, but go into hibernation by the first of August. Remedial measures. Spraying with an arsenical as is practiced for the codlin- moth will destroy a small percentage of the apple curculios, but extensive experiments in Illinois have shown that addi- tional applications for the curculios do not kill enough to pay for the expense incurred. (Curculios thrive in overgrown, crowded, unpruned and uncultivated orchards, and may best be controlled by remedying these conditions. The trees should be pruned so as to admit as much sunlight as practicable, the ground should be kept free from weeds and the trees should not be so close together as to shade the entire ground. A large proportion of the infested apples drop and the insect completes its development in the fallen fruit. It is necessary, however, that the fruit remain in the shade, since even a few hours of direct sunlight is fatal to both larvse and pupse. Where the ground has been kept clean and smooth it will pay to rake the windfalls out into the sun, where they will dry up. This should be done early in the season, for great numbers of curculios develop in small apples not larger than a pea. Wild thorn 38 FRUIT INSECTS apples in hedges and wood lots adjoining orchards serve as cen- ters of infestation, and should be destroyed. Grassy borders and driveways, and particularly stone fences and stone piles serve as excellent hibernating quarters for the beetles. Clean orcharding is the most effective preventive of curculio attacks. References Uiley, 3d Mo. Kept. pp. 29-35. 1871. 111. Agr. Exp. Sta. Bull. 98. 1905. W. Va. Agr. Exp. Sta. Bull. 126. 1910. The Apple Weevil Pseudanthonomus cratcegi Walsh While generally distributed over the eastern United States, this weevil has been reported as injuring apples only in West Virginia. Walsh in 1866 reared the beetle from a Cecidomyiid gall on the wild thorn. The beetle is much smaller than the species last treated, being only yV inch in length. It is of a uniform light brown color and has the wing covers deeply striated but without hiunps or tubercles of any kind (Fig. 40) . The beetles emerge from hibernation in early spring. They feed on the foliage more or less throughout the season, but their principal food is the pulp of the fruit, which they obtain through minute punctures made in the skin. The minute, yellowish-white oval eggs are deposited in cavities in the pulp eaten out by the females. The opening of the cavity is then sealed with a drop of excrement. The eggs Fiu. 40. — The apple weevil (X 15). APPLE INSECTS 39 hatch in 4 or 5 days, and the yellowish-white footless grub eats out a winding burrow in the fruit or may form a large irregular feeding chamber. The grubs are unable to develop in apples that continue to grow, being killed in many cases by the pressure of the proliferating plant c(^lls. Under favorable conditions they become full-grown, and pupate in about 30 days on the average. The eggs are often laid in decaying fruit, and as many as 20 beetles have been reared from a single apple, although 4 or 5 is the more usual number. The pupae occupy cells inside the fruit, and in a little over a week transform to beetles. The beetles remain about the trees during the re- mainder of the season, going into hibernation at the approach of cold weather. There is only one generation a year. Remedial treatment. The fact that the beetles feed more or less on the foliage makes it possible to kill them by spraying with arsenate of lead applied as for the codlin-moth. It has been shown in West Virginia that when the trees are treated in this way the injurious work of this weevil is completely prevented. Reference W. Va. Agv. Exp. Sta. Bull. 12(3. 1910. The Green Fruit-worms Xylina antennata Walker Xylina laticinerea Grote Xylina grotei Riley While very widely distributed throughout the United States and Canada, these three very closely related species have only occasionally attracted attention by their attacks on apples and other fruits. They caused considerable loss in Illinois and Missouri in 1870 and hi New York in 1877, 1890 and 1913. 40 FRUIT INSPJCrS jk They are more frequently found feeding on foliage of various forest trees, notably poplar, soft maple, hickory, wild cherry and boxelder. In addition to the apple they also attack the fruit of the pear, peach, plum, apricot, quince and currant. The green fruit-worms are large, light yellowish or apple green caterpillars (Fig. 41), with a Fig. 41. — Grt'cii I'niit-vvornis feeding on i i i • young apples. narrow cream-colored stripe down the middle of the back, a wide cream-colored stripe along each side and many similarly colored mottlings or spots which sometimes form quite distinct stripes along the body above the broad lateral stripes. When fully grown they range from one to one and a half ^^ inches in length. They work during May and the first half of June. When young they feed upon the foliage or buds so that when the fruit is large enough for them to eat they are found to be about half grown. The caterpillars do not bore into the fruit, but usually begin eating on one side and often con- tinue feeding until nearly half of the fruit is eaten. They go from fruit to fruit, one caterpillar thus ruining several fruits ; in some orchards they have been known to destroy over a quarter of the crop. If the cavity eaten in the apple is not too large, it ^ , .., _ may heal over, leaving a light brown corky scar. Pupaof"^the The green fruit-worms do most of their damage to ^^^^" ^^"^*" , . . ^ worm. the 3^oung Iruits m May, but some of them continue working until nearly the middle of June. During the first week in June most of the caterpillars get their full growth APPLE INSECTS 41 Fig. 43. Green fruit-vvoriu antennata (X If). moth, X. and burrow into the soil beneath the trees to a depth of from one to three inches. Here they roll and twist their bodies about until a smooth earthen cell is formed . Most of them then spin about th(^m- selves a very thin silken cocoon ; some spin no cocoon. Soon after building the cocoon or earthen cell the caterpillar transforms to a dark brown pupa (Fig. 42). In about three months, or about the middle of September, the moths (Fig. 43) emerge and go into hibernation in sheltered nooks ; some of the ])upse, however, do not transform till early the following spring. The moths appear on the trees in March or April, and deposit their nearly globular, distinctly ridged, yellowish eggs singly on the bark of the smaller branches (Fig. 44). Means of control. As the green fruit-worms are about half grown when they begin feeding on the fruit it is then a very difficult matter to kill them with a poison spray. Earlier, when feeding on the buds and newly opened leaves, many of the young worms could doubtless be destroyed by a thorough application of 5. or 6 pounds in 100 gallons of water 'f'W' m FiCx. 44. — Green fruit-worm egg on apple twig, greatly enlarged. arsenate of lead, or dilute lime-sulfur solution. Reference Cornell Agr. Exp. Sta. Bull. 123. 189G. CHAPTER TTI APPLE INSECTS -BUDS AND FOLIAGE Tmo Hud-moth Tmetocera ocellana S(;hiffermullor This is one of tlie most numerous, (Icslructivo, and wide- spread of tlie inse(;ts attac^kin^- the opening- l)U(ls of fruit trees. It is a European insect which has l)een ravaging American orchards for nearly a century, and is now mon^ or less injurious yearly from Nova Scotia through Canada and the northern half of the United States to Oregon and Washington. Infested nursery stock is the principal source of new infestations. Working in the opening })uds, it often " nips in the bud " a prospe(;tive crop of fruit, and it is especially destructive on recently budded or grafted trees and nursery stock. It more commonly infests api:)le trees, but pear, plum, cherry, quince, and peach trees and bla('k])erry ])ushes are also attacked and sometimes seriously injured. Th(^ half-grown, dark brown, black-headed caterpillars hibernate in obscure little silken hibernacula on the bark of the twigs, usually near the ])uds. Early in the spring, or as soon as the buds begin to op(^n in April or May, these caterpillars leave their hibernating quarters and get into the opening buds (Fig. 45) , wher(; they feed upon the central expanding leaves and flowers, tying them together with silken threads. The petiole of one of the leaves is often nearly severed, and the edge of the wilting leaf is then rolled into a tube lined sparsely with silk 42 APPLE INSECTS — BffDS AND FOLIAGE 43 ^ in which the caterpillar lives for 6 or 7 weeks, going out to feed mostly at night. It often draws other leaves toward it and fastens them, thus forming a sort of nest. Some of the partly eaten leaves soon turn brown, thus rendering the work of the insect quite conspicuous. Where terminal buds are attacked the caterpillar some- times burrows down the shoot for 2 or 3 inches, causing it to die. The mature, nearly naked caterpillar is about half an inch in length, and of a cinnamon- brown color, with the head, thoracic shield and true legs black. Becoming full-grown in June, the caterpillars transform, and ten days are spent as brown pupa in silken lined cocoons formed of leaves either rolled or tied together in the nests. The moths emerge over a period of six weeks, from June 5 to July 15 in New York. The dark ash-gray moths, with a broad, cream-white band across the front wings, which have an ex- panse of 5 of an inch, are night-flyers and closely mimic the bark when at rest (Fig. 46). A few days after emerging, the females lay mi- nute, flattened, disk- like, oval, nearly transparent, smooth eggs either singly or in small overlapping clusters on the leaves Knight photo (X 4). ^Yig. 47). In a week or ten days a little black-headed, greenish caterpillar hatches, makes a silken tube open at both ends and sallies forth to feed Fig. 45. — Opening apple bud infested with a hud-moth cat- erpillar, showing the brownish particles thrown out at the tip by the larva. Fig. 46. — Bud-moth. 44 FRUIT INSECTS Fig. 47. moth. - Eggs of the bud- Greatly enlarged. upon the skin and inner tissues of the leaf, usually on the under- side along the midrib. A thin protecting layer of silk is spun over their feeding grounds, and the skeletonized portion of the leaf soon turns brown. Oftentimes when working on the underside of a leaf that touches an apple the little cat- erpillar eats into the fruit in several places, causing a blemish in the mature apple as shown in Figure 48. Most of this injury is usually at- tributed to the summer brood of codlin-moth larvae. Turning brown in color in a day or two, the little caterpillars continue to feed on the leaves during July, August and a part of September, molting 3 or 4 times and getting about half grown. Some of them leave the foliage and go into winter quarters on the twigs early in August. Before the leaves drop all are snugly tucked away in their very obscure silken winter homes about I of an inch in length and covered with bits of dirt or some- times made under a convenient piece of dead bud scale. There is thus but a single broofl of th(^ bud-moth annually. Five little parasites work upon this insect in Europe, and at least three parasites {Phytodietus vul- garis, Pimpla sp. and Microdus laticinctus) help considerably to check it in America. Birds also get some of the brown cat- erpillars, and a large muddauber wasp, Odynerus catskillensis, Fig. 48. — Apple injured by young bud-moth caterpillars in August. APPLE INSECTS — BUDS AND FOLIAGE 45 sometimes stores its cells with them to serve as deUcious morsels for its baby grubs when they hatch. Remedial treatments. This bud-moth is a difficult insect to control. In nurseries or young orchards it is often practicable to go over the trees in May, when the " nests " are rendered quite conspicuous by one or two brown, dead leaves, and either pick off and destroy the nests, or crush them on the trees with the fingers so as to kill the inclosed caterpillars or pupae. Skillful and thorough work with a poison spray will also control the bud -moth. Make two applications of arsenate of lead, 4 pounds in 100 gallons of water ; the first when the flower clusters first appear, and the second just before the blossoms open. Many growers add the poison to the lime-sulfur used against the scale and blister-mite, making the application just as the tips of the buds begin to show green, and thus avoid a separate spraying for the bud-moth. Recent ex- periments, however, have shown that this early application of the poison has little effect. If these applications are thoroughly made and followed by the spraying usually given for the codlin- moth just after the blossoms drop, this pest can be effectually controlled. References Cornell Agr. Exp. Sta. Bull. 50. 1893. Cornell Agr. Exp. Sta. Bull. 107, pp. 57-66. 1896. The Fringed-wing Apple Bud-moth Holcocera maligemmella Murtfeldt Since about 1895 the light, greenish-yellow caterpillars, a})out \ of an inch long with a black head and thoracic shield, of this satiny, brownish-buff Tineid moth have been more or less injurious in apple orchards in western Missouri and adjoin- ing states. The moths, which measure across expanded wings about I of an inch, emerge from the ground early in April, lay 46 FRUIT INSECTS their light yellow, oval, roughened eggs singly in the opening buds, and in a week or two the caterpillars appear. They fasten together some of the expanding leaves, feed within and work their way down into the center of the base of the open flower and leaf buds and developing shoots, often causing them to break off near the base. Thus the growth of the shoot is stopped, the terminal leaves killed and the prospective crop of fruit destroyed. In about four weeks the caterpillars get their growth, crawl into the ground an inch or two, transform in a delicate, white, silken cocoon through tiny, l)rown pupae to the moths which appear about the middle of July and lay eggs on the leaves for a second but less destructive brood of caterpillars which work in and kill the terminal leaves and buds on the new shoots. Becoming full-grown late in August, the caterpillars transform to pupae in the ground and hibernate in that stage. To control this fringed-wing apple bud-moth requires the most thorough work with a poison spray before the blossoms open, beginning just as soon as any green shows on the buds. Three applications of Paris green (1 pound in 100 gallons, with 3 pounds lime) have given good results. Two thorough sprayings with arsenate of lead before blossoming would doubtless prove equally effective. Reference Mo. Agr. Exp. Sta. Bull. 42. 1898. The Apple Bud-worm Exartema fnalanum Fernald This insect first attracted attention as an apple pest in northern Illinois in 1881, and has rarely been injurious since. The young caterpillars or bud-worms hatching from eggs laid singly on the terminal buds, are yellowish-white, tinged with pink or green. They devour the buds, then forming sort of a burrow by fastening a lower leaf -stalk to the branch ; they feed APPLE INSECTS — BUDS AND FOLIAGE 47 upon this leaf and the newly formed wood, sometimes burrowing into it a short distance. In a short time this burrow is deserted, and the caterpillar, now of a dark flesh color, with polished black head and cervical shield, constructs a short, yellowish, woolly tube or case on the leaves, from which it sallies forth to another. When full-grown in June the caterpillars are about J an inch long, and they transform in their cases to the adult insect, a Tortricid moth. There is but one brood annually. The front wings of the moth expand about J an inch, and at the base and tip of each there is a large grayish-brown spot, those at the base being darker and the others mottled with white ; be- tween these spots the wings are white, with silvery reflections. The tips of infested })ranches die back to the base of the first perfect leaf, and the trees present a blasted appearance. Apple trees only are attacked by this bud-worm, and it has a relentless enemy in the form of the small parasitic fly, Microdus eari- noides. As their work on the terminal buds and leaves is quite con- spicuous, many of the young caterpillars can be destroyed in their burrows by pruning off and burning the infested tips. Later, in June, when they are feeding from their woolly cases on the leaves, a poison spray would prove an effective treatment. The Cigar-case-bearer Coleophora fletcherella Fernald About 1890 this interesting little case-bearer first appeared in injurious numbers in apple, pear and plum orchards in New York and Canada, where it continues to do more or less damage each year. It has been reportt^l from New Mexico, Montana, Maine and British Columbia, when* it was doubtless introduced on nursery stock. (3n account of its small size and peculiar habits, the insect itself will rarely be seen by the* fruit-grrowor. 48 FRUir INSECTS Fig. 49. — Hibernating cases of the cigar- case-bearer. Herrick photo. Enlarged. but the curious little cigar-shaped suits in which the caterpillars live in May and June are quite conspicuous on the foliage. The caterpillar protrudes itself from its case, eats a tiny round hole through the skin of the leaf and then mines out the in- terior tissue as far as it can reach and still retain its case. Thus many small, blotch mines are made which soon turn brown, and often whole leaves are thus mined out. About September 15, the insect goes into hibernation as a minute, half-grown caterpillar in a tiny curved case attached to the twigs (Fig. 49). About the middle of April, the caterpillars move and proceed to eat holes in the opening buds, the expanding leave i^ the stems of the flowers and fruits and the young fruits (Fig. 50). Additions are built on to the winter case, but in about a month the dark, orange-colored, black-headed caterpillar, scarcely J of an inch long, deftly makes, by mining and cutting out a cigar-shaped area of the leaf, its larger cigar-shaped case or suit. In the latter part of June the caterpillars cease feeding, securely fasten the cases to the leaves or branches, and in about three weeks transform within through light brown pupae to the tiny steel-gray moths, with a wing expanse of about I of an inch (Fig. 51). The females soon lay minute, yellow, pitted eggs among the hairs on the young leaves. Hatching in about two weeks, the tiny caterpillars work as Fig. 50. — Cigar-case-bearer attached to young pear which also shows several scars made by other case-bearers. APPLE INSECTS — BUDS AND FOLIAGE 49 miners in the leaves for two or three weeks, then construct their curious Uttle curved cases from bits of the skins of the leaves, and by the middle of September migrate to the twigs, where they hibernate. This cigar-case-bearer is capable of doing much damage to the young fruit and the foliage of fruit trees, and as it is pro- tected by a case and mines in the leaves, it requires skillful and thorough spraying to successfully con- trol it. Possibly the strong sprays used against the San Jose scale in winter might reach the hibernating caterpillars in their tiny curved cases on the twigs. Early in the spring, or soon after the buds open and the caterpillars begin work, a thorough application of kerosene emulsion, diluted with 9 parts of water, has proved effective in Canada. In the commercial orchards of western New York case-bearers are usually controlled by the use of arsenate of lead, as recommended for the })ud-moth, page 42. IIefekences Fig. 51. Cigar-case-bearer moth (X 7). Cornell Agr. Exp. Sta. Bull. 93. 1895. Fletcher, Kept. Ent. Ottawa, for 1894, pp. 201-206. U. S. Bur. Ent. Bull. 80, Ft. II. 1909. 1895. The Pistol Case-bearer Coleophora malivorella Riley This interesting insect spends about seven months of its life (from about September 1 to April 1) in hibernation as a minute, half-grown caterpillar in a small, pistol-shaped case 50 FRUIT INSECTS about J of an inch long attached to the twigs of its food-plants, which are the apple especially, but also include the quince, plum and cherry. Early in April the little cases move and the caterpillars bore into and devour the swelling buds, expanding leaves, and espe- cially the flowers. For four days about May 1, the cases may be found again fastened to the twigs while the cater- pillars are molting inside. Unlike the cigar-case-bearer, this insect does not make a complete new case as it grows, but simply makes silken ad- ditions to the ends and sides of the old case. Most of their feeding is done openly and not as miners, irregular holes being eaten in the leaves, often skeleton- izing them. The caterpillars never leave their cases, but project themselves out far enough to get a foothold, then begin to eat, holding the case at a consider- able angle from the leaf. They are most destructive on the flowers, where they eat the petals and stems, thus destroy- ing the prospective crop. Sometimes they also bore into the young fruits. In the latter part of May they cease feeding, securely fasten the pistol-shaped cases, now Fig. Pist()l-c;i«c-l)earcrs attached for pupation. Pistol-case-bearer moth (X 5). APPLE INSECTS -^nUD^ AND FOLIAGE 51 about J of an inch lon^", to the smaller brandies (Fig. 52). These dark brown, bark-colored cases are made lar<4-ely of silk, particles of excrement and tlu^ pubescence of the leaves. Turn- ing around in its case, the orange-colored cateri)illar witli black head, thoracic shield and legs, transforms in about a month through a light brown pupa to a pretty, little, dark drab-colored Tineid moth (Fig. 53) with a wing expanse of about J an inch. It emerges from the '' handh 'ud of the Fig. 54. — Pistol-case- bearer, moth resting on its empty ease. pistol (Fig. 54). On the basal third of the front wings white scales predominate in the fe- males especially, the legs and antennae have alternating rings of dark and white scales, and there is a conspicuous tuft of scales on the basal joint of each antennae. The females glue their minute, pretty, cinnamon- colored, inverted cup-like, ribbed eggs to the surface of the leaves (Fig. 55). The tiny caterpillars hatch from these eggs in about a wxek, or late in July, and eat little holes in the leaves. They soon construct of silk and excrement little pistol-shaped cases to which they build additions until about September 1, when they begin to migrate to the twigs and there fasten their cases to the bark and hibernate until April. Since 1877 this insect has been very injurious in apple or- FiG. 55. — Eggs of the pistol case-bearer. Greatly enlarged. 52 FEU IT INSECTS cliards at int(U-val8 of several years in New York and Pennsyl- vania. It is widely distributed in Canada and the Unitcnl States, extending- westward to New Mexico, wluM'e it was doubt- less earri(>d on nursery stock. It is ca|xd)le ol" very d(\structive work and sometimes becomes so numerous that there is a (rase- Ix^arer for every two or thi-ee buds. 'iVo or three tiny ])arasites helj) to control it. I^^xperiments show that this pistol-case-beanT can \n) effec- tually controlled with two a|)|)licati{)ns of a, poison spray before the blossoms open, as reconunended loi- tlie bud-moth, paji;e 45. lll'M'KKIONCIOS Lintner, 1st Rept. SUilo lOiil., N. V., |)i). Il'»;i-1('>7. 1882. (^oriK'll Af?r. Kxp. Sla,. Hull. 121. IS97. N. Y. ((Jencva) Aj^t. K.\p. Sla. Hull. 122. 1S<)7. TiiK Palmer-worm Ypsolophus ligulellus Hiibner This little Tineid moth occurs throughout the eastern half of the Unit(Hl States, but has done n()tic(vd)le injury only in New York and the New T^n^land stat(^s. It is a n^markable example of the " ups and downs " of insect life, as it suddenly appears over a larji;e area, does much damage for a year or two, tluMi as suddenly disappears, often remaining in obscurity for half a century or more. Its first outbreak ocH'urred in 1791 in New l^^ngland, followed ()2 years lat(T by the second over a wid(^r t(u-ritory, including N(nv York in 1853, and after waiting 57 years, or in 1900, it again ravaged ap])le orchards in New York. Its favorite food se(^ms to be the foliage^ and fruits of apple, oak foliage, and, curiously enough, the spongy oak-apple galls are sometimes eaten. The caterpillars or palmer-worms are only about ] ^)f ^^ii i^^ch in length when full-grown, and of a general olivaceous or brownish-green color, usually with a light APPLE INSECTS — fillDS AND FOLlAdK 53 brown head; soiik* arc (hirkcr in color, witli nearly black heads and thoracic shields. Two lab'ral and two dorsal whitish stripes give the dorsum the; appearance of being traversed by two broad, dark stripes and a similar nar- rower mesal stripe of the general body color (Fig. 5()). The active little palmer- worms move with a wrig- gling motion when ,, re, rr^u ^ ■ ■, * n ^ ^ Fig. 56. — The palmer-wonu m its scanty silken touched, and work net(xo) on the foliage and young fruits for 3 or 4 weeks in June. They skeletonize the foliage and spin down when disturbed, but are not loopers or measuring-worms, and although only a})out half as large as Fig. 57. — Youhk apples eaten into l)y paliner-wornvs. Note the caterpillars in the first and third apples from the right. canker-worms, may l)e more destructive, as they frequently eat large, deep holes into the sides of the young fruits (Fig. 57). They feed openly on the leaves, sometimes fastening 2 or 3 leaves 54 FRUIT INSECTS together with silk, or, often rolhng the edge of a leaf slightly, fasten it with silk threads and feed beneath this partial protec- tion. Late in June, these palmer- worms transform to tiny brown pupae (Fig. 58), which may be at- tached by a few silken threads, at their posterior ends, to the injured fflHHn leaves, or may be found on the BP"" ground. In about ten days there m emerges from these pupae the minute m sray or grayish-brown moths with M a wing expanse of little more than | t an inch (Fig. 59) . They are quite t?# variable in color and markings. '^y The front wings are more or less T sprinkled with black scales and Fig. 58. — Palmer-worm pupaj. marked with 4 small, black spots arranged obliquely near the middle and 6 or 7 black dots near the fringed edge. The hind wings are heavily fringed and of a dusky color with glossy azure-blue reflection. There is but a single brood of palmer-worms an- nually ; the moths which emerge early in July apparently hibernate and lay their tiny, delicate, pearly-white, ob- long-oval eggs in the spring. The eggs are laid on the under side of the opening leaves in May ; they are tuckcnl away among the hairs or deposited in the angles of the veins. Fig. 59. — Palmer-worm moth ; the wings on each side represent a different variety (X 5). APPLE INSECTS — BUDS AND FOLIAGE 55 Climatic conditions undoubtedly have; much to do with the " ups and downs " of this insect. Excessively dry weather in April and May favors the development, and heavy rains often knock many from the leaves in June, and they never get back. Many of the palmer- worms are also killed by the maggot of a tiny parasitic fly known as Apanteles sp. Palmer- worms can be controlled with one or two applications of arsenate of lead, 4 pounds in 100 gallons of water or dilute lime-sulfur solution. The application should be made at the first appear- ance of the caterpillars in early June. References Cornell A^r. Exp. Sta. Bull. 187. 1901. N. Y. (Geneva) Agr. Exp. Sta. Bull. 212, pp. 10-22. 1902. Click-beetles Corymbites caricinus Germar Corymhites tarsalis Melsheimer Corymbites cylindriformis Herbst These three slender brown click-beetles, from f to ^ an inch in length, sometimes swarm on to apple and pear trees in the spring and attack the opening buds and the flowers, denuding orchards of blossoms in some instances. Thus far their ravages have been confined to Nova Scotia, British Columbia and other localities in Canada. In their larval stage as wireworms, these click-beetles doubtless bred on the roots of grasses, either in the orchards if in sod or in near-by fields, so that thorough cultiva- tion in late fall would help much to reduce their numbers. As the beetles drop quickly and feign death when the tree is jarred, they can be readily captured on sheets or plum curculio-catchers. Or many of them would doubtless succumb to a strong poison spray of arsenate of lead, 6 or 8 pounds in 100 gallons. Reference Fletcher, Rept. Exp. Farms Ottawa 1895, p. 149, 1896. 56 FRUIT INSECTS The Ribbed Cocoon-maker of the Apple Bycculatrix ponvifoUella Cleme ns Fig. 60. Cocoons of the ribbed cocoon-niaker. The small Init conHpicuous whitish, distinctly ribbed co- coons, about J of an inch long, of this insect, often occur in large numbers in autumn on the undersides of the smaller branches .^^ of apple trees (Fig. r^^^m 60), and may first ■. reveal to the fruit grower its presence in the orchard. It is usually a local pest in widely separated orchards, but has a wide distribution over the eastern half of Canada and in the United States from Maine to Texas. Although it is capable of doing much damage to foliage, it is rarely a serious pest, and attacks only the apple, other fruit trees being apparently immune even when growing in close proximity to apples. A little brown pupa hibernates in the white cocoons, and when the leaves _ are unfolding in May it works halfway out of one end of the cocoon and there emerges a tiny, light brown moth about yo of an inch in length with each front wing marked with a large, dark brown spot (Fig. 61). In a few days, minute, pale green, elliptical, iridescent, roughened eggs are laid singly on the under surface of the leaves. The tiny caterpillars which hatch from these eggs in from 6 to 10 days burrow directly into the leaf, where for about a week they make narrow mines Fig. 61. — Ribbed cocoon-niaker moth (X 8). APPLE INSECTS — BUDS AND FOLIAGE 57 nearly f of an inch in length. It then comes out of this mine and makes a thin, white, silken molting cocoon (Fig. 62), within which its skin is shed in a few days, and the greenish- brown caterpillar feeds openly on the surface of the leaves near the edges. A second larger molting cocoon is made in about 4 days. Two days later the caterpillars appear in their last stage niid proceed to skeletonize the foliage for about a lMi||# Fig. 62. — Apple leaf showing mines and "molting cocoons" of the caterpillars, enlarged. week, finally wandering about to find a suitable place to spin their true ribbed cocoons early in July on the leaves, young fruits or twigs and larger limbs. It requires 3 or 4 hours to build one of these ribbed cocoons (Fig. 63). The pupal stage lasts from 1 to 2 weeks in these summer cocoons, most of the moths emerg- ing by August 1 in New York. The mines of the young cater- pillars are usually near the centers of the leaves, while most of the skeletonizing is done near the edges and always on the upper surface. When badly eaten, the leaves turn brown and curl. The caterpillars often hang suspended from the leaves by silken 58 FRIT IT INSECTS threads, and may be blown on to otluT food-plants near by, where their cocoons are sometimes found. In Maine there is apparently but one^ brood of this insect annually, as the moths did not appear until spring from pupse formed August 1. In southern New York, however, there are two distinct broods, the moths emerging in July lay eggs early in August and the second brood of caterpillars work on the leaves during August and September in the same manner as the first brood. Being more numerous, the work of the second brood is Fk;. 6."->. — Tho ribbed cocoou-niakcr biiildiufi; its roeoon. Enlarged. usually more conspicuous and extensive than that of the spring brood. Eighty per cent of the cocoons made in autumn ar(^ within two feet of the ends of the branches on the lower third of the trees. The summer brood is far less liable to be attacked by parasites and diseases, moths emerging from 80 to 90 per cent of the cocoons in July, whereas it is unusual for moths to emerge from more than 50 per cent of the winter cocoons. Five tiny hymenopter- ous parasites, Cirrospilus flavicindus, Encyrtus bucculatricis, Mesochorus politus, Apanteles caccecice and Zaporus sp., play an important part in checking this pest. Many of the cocoons are often stripped from the twigs by birds in winter, and in APPLE INSE(rrs — BUDS AND FOIJAGE 59 summer the caterpillars are frequently found in webs spun across the surfaces of the leaves by the spiders, Didyna foliacea and Araneus displicatiis. There is also a great mortality, sometimes nearly 50 per cent, among the larvae and pupae in the cocoons in autumn, due apparently to some disease, causing them to shrivel and become dry and hard. Remedial measures. Sprays of whale-oil soap (1 pound in 1 gallon of water), the lime-sulfur wash, and probably the miscible oils (1 gallon in 10 of water) applied thoroughly at any time during the winter or early spring, while the tree is dormant, will soak through the white cocoons and kill the hibernating pupae. Judicious prun- ing and burning of infested twigs in winter would destroy many. The application of a poison spray in the latter part of June will kill many of the tiny caterpillars then feeding on the leaves. Reference Cornell A^^r. Exp. Sta. Bull. 214. 1903. The Lei^seu Apple Leaf-uolleu Alceris minuta Robinson Throughout tlu^ eastern United States a small, pale yellowish- green caterpillar, about J of an inch long, with a yellow head and thoracic shield, often draws the opposite edges of apple leaves together upwards and fastens them with silk. Living within the shelter of this folded leaf it feeds over the inner surface, often partially skeletonizing the leaf and causing it to turn brown. Sometimes nursery stock and young orchards are so badly infested, a majority of the leaves being folded and brown, that from a distance the trees appear as if a fin) had swept through them, and much injury results. Older bearing trees are rarely seriously damaged by the insect. Besides being a serious menace to young apple trees, and sometimes attacking 60 FRUIT INSECTS pears also, it is the yellow-headed cran})erry worm, a destructive pest of cranl)erry bogs (see page 462). There are three generations or broods of this insect annually on apple in the latitude of Missouri, but it is two-brooded in the cranberry bogs of Massachusetts. The moths are dimorphic ; those of the one or two summer broods have bright, orange- colored front wings, while those of the autumn brood have slaty- gray front wings, often with a dusting of orange scales. The moths have a Aving expanse of about | of an inch. The third or dimorphic brood, bearing the varietal name of Cinderella, appear in September and October, and hibernate in sheltered places. In the spring these gray moths emerge from their winter quarters and lay their minute, disk-like yellow eggs on the unfolding young l(\aves. Two or three broods of the caterpillars fold the leaves during the growing season, the first working in May, the second in July, and the third brood, where it occurs, works in August or September. A single folded apple leaf usually furnishers sufficient food for a caterpillar. After feeding for 3 or 4 weeks, it spins a delicate, silken w(rl) or cocoon within tlur k^af, and then transforms to a small brown pupa about \ of an inch long, and chara(;teriz(rd by a curious knob-like })roj(M*tion from tlnr front of the head. In a w(H^k or ten days tlu^se pupie work tlurir way about half out of the foldcnl knaves, and the moths (^merge. This apple l(\af-folder has many parasitic; (rnemicrs which are often eff(H'tive nids in restricting its injuries. A Tachina-fly and several hymenopterous parasites an^ known to prcry upon the cat(irpillars, and in Michigan a Hock of l)irds, pro})ably th(r rusty grackle, have Ixurn seen destroying many of the pupa^, neatly picking them out of the folded leaves. Remedial measures. It is often practicable in nurseries and young orchards to employ men or boys to go through and pinch the folded leaves, thus destroying the caterpillars within. This should be done APPLE INSECTS — liZfDS ANT) FOLIAGE 61 early in the season when the first brood is working, so as to pre- vent the development of later broods. The insect can also be controlled with a poison spray. Spray thoroughly just as the eggs are hatching early in the spring, when th(^ first leaves are unfolding, with arsenate of lead, 4 to 6 pounds in 100 gallons of water. Repeat the application in a few days if necessary. If the first brood is missed or not treated, quite eff(»ctive work can also be done against thc^ later broods of caterpillars with the poison sprays if applied just as the eggs are hatching. References Forbes, 4th Ropt. Ent. Til., i)]). 75-8;'). 1889. Mo. Agr. Kxp. SI a. Bull. 36, pp. ()3-73. 189(). Iowa A^-. Kxp. St a. Boll. 102. 1909. The Apple Leaf-sewer Ancylis nubeculana Clemens This insect works on apple leaves in much the same way as the lesser apple leaf-folder, but it differs much in its life history. The greenish-yellow caterpillar is about § an inch long when full- grown and has a yellowish head and cervical shield, the latter with a conspicuous black spot near each outer hind corner. These caterpillars hatch in early June, soon fold over a portion of a leaf, and finally draw the opposite edges of the whole leaf together upwards and securely fasten or sew them with silk. Within this hollow shelter they feed on the green tissues during the rest of the season, becoming full-grown in autumn. Their leafy home is then lined with silk and the caterpillars hibernate therein in the fallen leaves. There is thus but a single brood annually, the (;aterpillars transforming through yellowish-brown pupse to the moths in about 10 days in April. The pupa? wriggle their way through the back of the decayed leaves and the moths continue to emerge for about a month. The oddly marked front 62 FRUir INSECTS wings of these Tortricid moths are white with brown mottlings and shades, and have an expanse of about J of an inch. This leaf -sewer rarely does serious injury, but in a few instances it has appeared in alarming numbers in orchards in western New York and in Ontario, Canada. Well cultivated orchards rarely suffer from this pest, as most of the hibernating caterpillars are buried with the fallen leaves. The effective method of raking up and burning the leaves in autumn would be practicable in some cases. A thorough application of a poison spray in early June will also kill many of the caterpillars then just beginning work on the foliage. The Fruit-tree Leaf-roller Ar chips argyrospila Walker Recorded as common throughout practically the whole of the United States, this insect is one of the most destructive of the leaf-rollers infesting fruit trees. It has been especially injurious in the orchards of New York, Missouri and Colorado, attacking apple, pear, cherry, plum, apricot, quince, rose, currant, raspberry and gooseberry, besides about a dozen different kinds of forest trees ; curiously enough peaches seem to be exempt from at- tack. It is thus a very general feeder, and it sometimes strips fruit trees and ruins many of the young fruits. The eggs are laid in June on the bark of the twigs in small flat, light l)rovvn or grayish ])atches, each patch containing about 150 eggs and covered with an impervious gummy substance (Fig. 64). The winter is passed in the egg Fig. 64. — Egg-mass of th( fruit-tree leaf-roller on ar apple twig, enlarged. Ilerricl photo. APPLE INSECTS — BUDS AND FOLIAGE 03 Fig. 65. — Larva of the fruit-tree leaf-roller be- ginning its nest on an apple leaf. Knight photo. stage. The caterpillars hatch about May 1, and enter the opening buds, where they roll and fasten the leaves loosely together with silken threads into a nest within which they feed (Figs. 65 and 66). After the fruits set, they are often in- cluded in the nests and ruined by the cat- erpillars eating large irregular holes in them (Fig. 67). The caterpillars get their growth in 2 or 3 weeks, and are then about f of an inch long, light green in color with the head, legs and thoracic shield varying from brown to black. About ten days are spent as a brown pupa (Fig. 68) in a delicate silken web or cocoon in the nest early in June. The moths emerge, and soon lay the peculiar patches of eggs on the bark, thus com- pleting the life-cycle of the single annual generation of this leaf-roller. The pretty little moths, measuring about f of an inch across the expanded wings, vary considerably in coloring and markings (Fig. 69). The front wings are rust-brown in color, marked with bands and spots of very pale yellow. Fig. 66. — Apple leaf rolled by the fruit-tree leaf-roller. Knight photo. 64 FRUIT INSECTS A number of hymenopterous parasites attack this leaf-roller. Toads often eat many of the caterpillars that drop from the trees, and red- winged blackbirds are efficient enemies in Colo- rado. Means of control. The leaf-roller has been found a difficult insect to control by ordinary spraying with arsenical poisons. Recent work in Colorado has shown, how- ever, that over 95 per cent of the eggs can be destroyed by one thorough application Fig. 67. Small apples eaten by the leaf-roller. Knight photo. Fig. 68. — Pupa of the fruit- tree leaf-roller. Knight photo. of a miscible oil, one part in 19 parts of water, made early in the spring while the trees are dormant. Efficient work against the eggs can also be done with a 10 per cent kerosene emulsion whenever for any reason it is undesirable to use a mis- cible oil. In case the eggs have not been treated it is necessary to resort to arsen- ical sprays to kill the young caterpillars. Use arsenate of lead, 6 pounds in 100 x. en T7 -^ ^ 1 r n .u gallous of watcr, making the Fig. 69. — Fruit-tree leaf-roller moth. ° ' ^ Knight photo (x 2|). first application just as soon APPLE INSECTS — BUDS AND FOLIAGE 65 as the buds begin to })urst, and the second \\\wn the blossom buds in the cluster begin to separate. This should be followed by the regular spray for the codlin-moth just as the last of the petals are falling. References Col. Agr. Exp. Sta. Bull. 19, pp. 3-9. 1892. Mo. Agr. Exp. Sta. Bull. 71. 1906. Cornell Agr. Exp. Sta. Bull. 311. 1912. Col. St. Ent. Circular 5. 1912. U. S. Bur. Ent. Bull. 116, Pt. V. 1913. The Oblique-banded Leaf-roller Ar chips rosaceana Harris The caterpillar of this leaf -roller varies from a light yellowish - brown to apple green in color and is about f of an inch in length, with a brownish-black head and thoracic shield, the latter usually with a whitish cephalic border, and often more or less green bordered with black. It lives in a nest similar to that of the bud-moth, formed by rolling or folding and tying together leaves of apple, pear, cherry, plum, peach, rose, raspberry, gooseberry, currant, strawberry, and several other trees, wild berries, red clover, more than half a dozen weeds, and eats into growing cotton bolls. The insect is common and widely distributed throughout the northern United States, where it is sometimes quite injurious, especially on apple trees. In addition to eating the leaves and often checking the growth of shoots, the cater- pillars sometimes attack the young fruits, either gnawing olT the skin or eating holes in them. There are two broods of the caterpillars annually, the first brood working in May and June and the second in July and August. When full-grown, the caterpillars transform in their nest to brown pupse, from which emerge in a week or ten days the 66 FRUIT INSECTS Fig. 70. — The ob- lique-banded leaf-roller moth, from life. Knight photo (X 3^). oblique-banded, light cinnamon-brown colored moths with a wing expanse of about an inch (Fig. 70). The front wings are reticulated with brown and each is crossed by three broad, oblique dark brown bands. The females lay their eggs in flat patches (Fig. 71) on the bark, and the insect hiber- nates in this stage. Fig. 71, Egg-mass of the oblique-banded leaf-roller. Herrick photo. A large ichneumon parasite, Glypta simpUcipes, destroys many of the caterpillars of this oblique-banded leaf-roller. The Four-banded Leaf-roller Eidia quadrifasciana Fernald This smaller, bright yellow caterpillar, about J an inch long, sometimes works on apple trees with and in much the same way as the oblique-banded leaf-roller. It webs a few leaves together and riddles them. The insect is widely distributed over the northern United States, and has done considerable injury in apple orchards in Delaware, working with the preceding species, and has helped to nearly strip trees in Canada. The moths are lemon-yellow, with the front wings reticulated with orange-red and each crossed by two narrow oblique darker bands. They measure across expanded wings about f of an inch, and have been reared late in May and June. These two Tortricid leaf-rollers can be controlled by the measures recommended for the fruit-tree leaf-roller on page 64. APPLE INSECTS — BUDS AND FOLIAGE 67 The Apple Leaf-skeletonizer Canarsia hammondl Riley The small greenish or })rownish caterpillars of this insect are about i an inch long, with 4 black, shining tubercles on the back just behind the head, and usually with a broad darker stripe along each side of the back. They live upon the upper side of the leaves under a thin web of silken threads, where they eat out the green pulpy portion, leaving a network of veinlets and giving the foliage a skeletonized and rusty or highly blighted appear- ance. There are two broods of the insect annually, one work- ing in midsummer and the other, usu- ally the more nu- merous, in Septem- ber and October. ^ _ ,, ^ Fig. 72. — The apple leaf-skcletonizer moth (X5). Sometimes the cater- pillars work gregariously in a nest of several leaves webbed together. Pupation occurs on the leaves and the second brood hibernates in the pupa stage. ' This Pyralid moth (Fig. 72) has an expanse of about one half an inch ; the front wings are glossy purplish-brown, each marked with two silvery- gray transverse bands. This leaf-skeletonizer is most common in the Mississippi Valley, where it is sometimes quite destructive in nurseries and young orchards. It works practically only on apple trees, rarely attacking plum and quince. Two or three parasites attack it. As the caterpillars feed openly on the surface of the foliage, they can be easily killed with a poison spray applied as early in the' season as their skeletonizing work is noticed. 68 FRUIT INSECTS IllOFIOUKNCE Forbes, 4th Uvpi. Stat(! Knt. 111., ])[). ryH-VA. 1889. TiiK Lkaf-crumflkr Mificola iti(h'r slujots, and soon con- struct their peculiar easels of silk, excrement and other debris. Additions are built on around th(^ larger (^nd of the case as the caterpillar grows, and alth()u«2;}i rou^h exteriorly, it is smoothly lined with silk on the hiterior. As cold weather approaches, the cases containing; the partially grown caterpillars are fas- tened up for hiber- . _ nation. There is but a single brood annually. At least three para- sites attack this leaf- crumpler and render efficient aid in hold- ing it in check. As their hibernating quarters are rendered quite conspicuous by surrounding brown and crumpled leaves, it is practicable to hand pick these winter nests from the bare trees, and thus destroy many of the young caterpillars. Over 140 have been taken from a single 6-year-old tree in Oklahoma, and one man collected 1584 of the winter nests in 4 hours. The insect can be easily controlled also by the thorough application of a poison spray just before and again just after the blossoming period of the trees. ^J§p'' Fig. 73. — The leaf-crumpler moth (X 32). 11eferen(;es Forbes, 4ih Rcpl. Slate Knt. 111. Mo. k^v. Exp. St a. Hull. 'M\, pp. pp. 65-74. 1889. 7;i-S(). 1896. Thk Trumpet Leaf-miner Tischcria malifoliella Clemens Over the eastern half of th(^ United States and Canada this is often the most common and destructive of the insects which 70 mm IT iNsiarrs rn.'ikc inincs in iipplc Ic-ivcs. Tlic IUII-^;r()WM ('}d,('rf)i]ln,rH ur(\ n;ii-l)()(li('(l, .*il)()iil ' of .'III incli in Icii^rlJi, wiUioiil, Ic^s, li^lil; ^rccn, vviMi lic.'id, I li<»t;icic .'ind .'ui.'il shields hrownisli. Tlicir hrown, hlislct-likc, Iriirnix'l-sli.'ipcd mines nhoiil ! oi" an \\\r.\i lonji; .'ire nlvvjiys tn.'i.de jusi heneidJi 1 he epidermis on the iJi)per side of Ihe le.'ives, l>ein^- se.'ireely n<)l.iee;d)l<' from I he nnder- side iiidess the \r:\\' is hel is iisu;illy crossed hy ereseenl-sh.'iped siripes of white (I'^i^. 7 1). In Ihe Noilh I here ;i!(' I wo Itroods of I his miner ,*iiinn.*illy, Ihe lirsl hrood <»!" (•;i( erpill.'irs working in .liine ;ind .Inly .'iihI AI'I'I.I': I y SECTS lilJDS AM) rf)L/A(Jf<: 71 00 im^:^ ^' Ific scfornl in Aufi;iist iu\<\ Scplcrnhrr. I'our hrooHs fiavo Ix'cn (>f>s('rvf;(l rif'!ir WiisfiiriMlon, tlir- rriirx-, f>r-in^ rnafJc in May, .July, August, ;iMf ;i, jr(;ri{;ratioT) \v;is ;if)oiil .'»;> (l;iy-. Tfif 1 r;i.nsforrn;i1 ion t firouji;}/ thf tiny, ^rccnisli-Urovvn [>up;<' ocriirs in tlif rnir)'-:-. In auturriri t}j(j mines arc licnvily lined wilfi vvliitc silk .'irxl the liltlf; cat(;rpil- larH paHK ihc winter- tlieicin on the r;illcn leaves. The jiHult, iris(U!t, is ;i, tiny Tinei'l rriotli vvith -liininM- H;irk brown front win^s, linked with purpli.-h ;uifl ). 'I hey rrieMSure ;i,eross expjuxled winii;s only about, { of an ineh. Sorn(;tinn(!S the mines nre so nu- merous ;is to in- volve muel) of thr' |e;if, wliieh eijrls •,u\({ fin;i,lly drops 2 -// y ^^ or ^> weeks enrlier yi<,.7r>. Thf. trufnjH^t, |c;if'-rnin( r rrif,tfi f / 10;. th;in usu.'il, thus f)reventin^ the full (levelo[)ment, of the fruit .'irid reducing the vitidity of the tree. Sixty-ei^ht e;i,t erpillars h;i,ve b(3en found working on ;i single le;if. On lar^(; tr(!(;s, the foliaj!;^; on the hi}i;hef br;inehes i,^ usu;illy more seriously infested. The f.'ivorile food-pl;ird of this native le;d"-miner is the eultj- vat/cd {i,pf>le, but it, ;ilso breeds on native cni\) and haw tn^es. 'Hie trumpet -sh;iped mines in the leaves of blaekf>erry and rasf)berry usually idtributcd to this inHoct are now eonsidorcd to be tfi(! work of two other speeies, Ww Tischeria (imm and roiidicold of Vn-y and I)oll. At least half a dozen tiny liymeno|)t erous f)arasites destroy many of th(;s(! miners, thus doin^ mueli to prev(;nt, the insect from increasing to destructive numbers. Uemedial treatment. As this insect hibernates on the fallen leaves, many of them FRUIT ly SECTS can be destroyed by plowing infested orchards either in late fall or early spring. Thoroughly cultivated orchards will rarely suffer serious injur}- from this miner. Experiments indicate that many of the larvLi^ and pup^B can be killed in the mines by thorough applications of 10 or 15 per cent kerosene lime emulsion. Just as effective work with less danger of in- juring the foliage could doubtless be done with " Black Leaf 40 " tobacco extract, one pint in 100 gallons of water, adding 4 pounds of soap to each 100 gallons to make the Uquid stick and spread better. References Briinn, Cornell Univ. Exp. Sta., Second Kept., pp. 155-157. Forbes, 4th Kept. State Ent. 111., pp. 45-50. 1889. Conn. (Storrs) Agr. Exp. Sta. Bull. 45. 1906. U. S. Bur. Ent. Bull. 68, Pt. III. 1907. Del. Agr. Exp. Sta. Bull. 87, pp. 3-9. 1910. 1883. Some Lesser Leaf-miners of the Apple The following four species of small caterpillars work as miners in the leaves of apple, and while often numerous enough to attract attention, they rarely appear in sufficient numbers to do serious injur}-. The spotted tentiform leaf-miner {Lithocolletes blancardella Fabricius) . The tiny light yellow caterpillars, only J of an inch long, make a small mine a})out J an inch long on the lower surface of the leaf, which causes a slight crimp- ing of the leaf, thus Fig. 76. — The moth of the spotted tentiform leaf- ^ivmg the mme a miner (X 12). tent-likc appear- APPLE INSECTS — BUDS AND FOLIAGE 73 ance. From the upi)or surface, the mine has a spotted appearance due to the caterpillars not mining out the whole interior, but eating a little here and there in the mine. The mines are finished in September, the caterpillars transform to pupae therein, and the winter is passed in this stage on the fallen leaves. The minute Tineid moths which emerge in the spring have golden brown front wings marked with white streaks and spots and a black apical spot (Fig. 76). This European miner is quite common on apple leaves in the eastern United States, l)ut has not yet been recorded as doing serious injury. References Brunn, Cornell Univ. Exp. Sta., Sooond Ropt., pp. 14S-ir)(). 1883. The unspotted tentiform leaf -miner (Or nix genmiatella Packard) . The tentiform mines of this insect are larger, and distort the leaves more than those of the preceding species (Fig. 77). The ^* grayish caterpillars, ^ about of an inch long, have a row of 6 black spots across the head and 4 larger ones across the dorsum of the first thoracic seg- ment. They eat the whole interior except the veinlets, so that the mine appears brownish but not \ spotted on the upper surface. When nearly ^^^ ^^ _ full-grown the cater- :/ Mines of the unspotted tentiform leaf-miner. 74 FRUIT INSECTS pillars leave their mines, and rolling over the edge of the leaf feed beneath for a short time, then line these retreats heavily with a silken cocoon within which they pupate. There are several broods each season. The tiny, dark, steel-gray moths emerge in the spring and measure only J of an inch across the expanded wings. This miner is widely distributed across the northern half of the United States, and is ap- parently more common than the spotted tentiform miner. In some cases two-thirds of the leaves in orchards have been distorted by from 2 to 4 of the unspotted mines, yet no very serious injury resulted. The insect also attacks pear and wild cherry foliage. References Brunn, Cornell Univ. Exp. Sta., Second Rept., pp. 151-154. 1883. Forbes, 4th Rept. State Ent. III., pp. 51-57. 1889. N. Y. (Geneva) Agr. Exp. Sta. Bull. 180, pp. 131-134. 1900. The serpentine leaf-miner (Nepticala pomivorella Packard). The tiny, dark, emerald-green caterpillars, about yV of ^^ inch long, make narrow, tortuous or serpentine mines, often 2 inches in length and less than yV of ^t^ i^ich wide just beneath the upper surface of the leaves of the apple and pear. The first half or two thirds of the mine is broader and nearly filled with a continuous zigzagging thread of black excrement. The insect is quite common in Canada and the northeastern United States. In October, the tiny green caterpillars are sometimes seen hanging by silken threads from the leaves. They soon find their way to the twigs, where they spin small, oval, dense, brown cocoons about | of an inch long on the back, often in a crotch. These cocoons resemble, and could be easily mistaken for, Lecanium scales. In May the caterpillars trans- form through brilliant green pupae to the minute, shining, pur- plish-black moths with tufted, reddish-yellow head, that emerge early in June. Thus far no very serious injury has been re- corded by this interesting little Tineid serpentine miner. APPLE INSECTS — BUDS AND FOLIAGE 75 The resplendent shield-bearer (Coptodisca splendor if erella Clemens). Throughout the northern United States, from Maine to Minnesota often there may be found attached to the bark of apple, pear, quince, thorn-apple and wild cherry trees curi- ous little, oval, disk-shaped, seed- like, yellowish bodies about yq of an inch long (Fig. 78). From these little shields or cases, fastened to the bark at one end by a silken button, there emerges in May a tiny, bril- liantly colored, golden-headed moth (Fig. 79). The basal half of the ^'''- /.v; ~ ^^''T'''!'''?- TJ" . coons of the resplendent shield- front wmgs are leaden-gray with a bearer. resplendent luster and the remainder golden with silvery and dark brownish streaks. These beautiful little creatures run about on the leaves in the sunshine and lay their eggs, from which hatch the tiny, light, yellowish-brown, legless caterpillars about \ of an inch in length. These make an irregular dark-colored blotch mine, about \ of an inch in diameter, in the leaves and observable from both sur- faces. When full-grown, the caterpillars line a por- tion of the mine with silk, deftly cut it out and thus Fig. 79. -The moth of the resplendent f^j.^ ^j^^jj, seed-like shield, shield-bearer (X 10). Dropping from the leaves in July b}^ a silken thread, they finally reach the bark or the ground, or are blown to other trees, where the cases are fastened. A second brood of the little miners works on the leaves in September and during October they fasten their cases to the bark and hibernate therein as caterpillars. Several quite serious outbreaks of this tiny shield-bearer 76 FRUIT INSECTS have occurred at Washington, in Connecticut and in Michigan on apple, quince and wild cherry, sometimes 25 or 30 mines occurring in a single leaf. The bark of the trunk and larger branches were fairly covered with the hibernating cases, 47 having been counted on a spot not larger than a dime. Reference Comstock, Rept. U. S. Ent. for 1879, pp. 210-213. Natural enemies of the lesser leaf-miners of the apple. All of these little leaf-miners have enemies which are more or less effective aids in preventing their occurrence in injurious numbers. At least two tiny Chalcid parasites, Sympiesis nigrifemora and Astichus tischeriae attack both the spotted and unspotted tentiform-miners. Ants often tear open the cases of the resplendent shield-bearer and devour the inclosed caterpillar or pupa ; two minute hymenopterous parasites also attack this miner. We have bred a tiny parasite from the serpentine miner, and many of the scale-like hibernating cocoons have been found in the stomachs of chickadees. Remedial treatments. In well cultivated and thoroughly si)rayed orchards, leaf- miners rarely l)ecome abundant enough to cause appreciable loss, and special treatment is therefore rarely m^cessary. As all of these lesser leaf-miners feed insid(^ th(^ leaves they cannot be effectively reached with poison sprays. For the tentiform- miners, resort to the treatments recommended for the trumpet leaf-miner. Possibly a spray of " Black Leaf 40 " tobacco ex- tract, 1 pint in 100 gallons of water, to which 4 or 5 pounds of soap have been added would penetrate mines and kill the cater- pillars of the shield-bearer and serpentine-miner. When very numerous many of the cases of the shield-miner could be scraped from the trees and destroyed. APPLE INSECTS — BUDS ANT) FOLIAGE 11 The Spring Canker-worm Paleacrita vernata Peck Canker-worms are among the oklest and most destructive of American orchard j^ests. The term " cancker-worme " appar- ently originated in England in 1530, and was used for several different insects in the first authorized English version of the Bible in 1611. As early as 1661, John Hull quaintly related that " the canker-worm hath for four years devoured most of the apples in Boston, that the apple trees look in June as if it was the 9th month" (meaning November). Several other seri- ous outbreaks of canker-worms were recorded in New England during the next century. Although the scientific name of vernata was applied to these canker-worms in 1795, and another name, pometaria, was proposed for some of the moths in 1841, it was not demonstrated until 1873 that two quite different species of insects had been masquerading as the canker-worm in America for more than 200 years. Canker-worms belong to the Geometrid group of moths whose caterpillars are called measuring-worms, span-worms or loopers from their peculiar manner of walking. Although several kinds of these measuring-worms are destructive to fruits, often working in the same orchards, the term canker-worm is restricted to the two distinct species recognized in 1873 and then given the common names of the spring canker-worm and the fall canker-worm. Both of these native species often occur together in injurious numbers in the same locality. The apple and elm are favorite food-plants, although several other fruit and shade trees are often attacked. The caterpillars appear on the trees in early spring and work mostly during May, skeletonizing the leaves, which soon turn brown. In June badly infested trees or or- chards often appear from a distance as though a fire had swept 78 FRUIT INSECTS through them. Like many other msect pests, canker-worms have their '^ ups and downs," or periods of increase and de- crease. Usually their destructive period lasts from 3 to 5 years or more before their enemies and climatic conditions succeed in bringing about the ''down" period, which may last 10 or more years. The defoliated trees grow weaker each year, 11^ ^^^^5? J^g w H i v-'*^ "'^^^^B^S 1^1^ Hi w^^^^^^Su ^^^p Br' ^iS^^Hr'^K^ m r Fig. 80. — Canker-worm moths caught on sticky band trunk. hile ascending tree mature but little fruit, and may finally succumb to the ravages of the hordes of canker-worms. If disturbed, the caterpillars often cling with their hind pro-legs and stand out straight, stiff and motionless, this strange attitude giving them a protective resemblance to the smaller twigs or leaf -stems ; or they may drop suddenly and swing suspended in the air by a silken cord until the threatened danger has apparently passed, when they APPLE INSECTS — BUDS AND FOLIAGE 79 resume their normal looping ]K)sitions or ascend their ropes somewhat sailor-fashion. The male canker-worm moths have fully (levelojxMl win<»;s, while the females are practically wingless, only short stubs of wings being ])resent. This lack of wings ren(l(M\s it nec(\ssary for the females to crawl up the trees to lay t lunr eggs, and affords an opportunity to apply certain effective barrier remedial measures (Fig. 80). The moths are active only at night, and often ascend the trees in the greatest numbers between 7 P.M. and 10 p.m. We have seen hun- dreds of the females ascending a single tree during the eve- ning in a badly in- fested orchard ; they are little disturbed by lights brought near. Many of them often secrete themselves in the crevices of the bark during the day. There are striking and easily discernible structural differences between the spring and the fall canker- worms in all four stages of their life-cycles. The spring canker-worm is common in Canada and in the northern United States from Maine westward to Kansas, thence southward through the Mississippi Valley to Texas. It also occurs in California. It is the species most often destructive in apple orchards, especially in its western range. The moths practically always emerge in early spring, sometimes during warm spells in February, but usually in March and April. They may continue to go up the trees for from 6 to 10 weeks. We have reared male moths varying in wing expanse from f to Fig. 81. — Spring canker-worm, male moth (X 2). 80 FRUIT INSECTS \ v- ^ l\ r Fig. 82 — Spring canker- worm, female moth (X2). IJ inches. The wings have a silky dehcate appearance, the hind ones being unmarked and pale ash gray ; on the slightly darker, pale brownish-gray front wings usually three transverse, jagged, dark lines can be discerned, especially on the front edge of the wings (Fig. 81). The egg-laden wingless females are nearly J an inch long and of a rabbit-gray color, with white bands on the legs and usually a distinct black stripe along the middle of the back (Fig. 82). Both sexes of the moths have on top of each of the first seven abdominal segments two** transverse rows of sharp reddish spines projecting backward ; as there are no spines on the moths of the fall canker- worm it is easy to distinguish the two species of canker-worms in the moth stage. A single female moth of the spring canker-worm may lay over 400 eggs, which she tucks away in small, irregular pits or clusters in the crevices under bark scales and moss on the trunk and larger limbs of the trees. The delicate, slightly ridged, oval eggs are about 5^0 of an inch long and of a dark iridescent metaUic buff or purplish color (Fig. 83). The eggs hatch early in May, and the caterpillars feed for about a month on the pulpy portions of the leaves, thus skeletonizing them. The full-grown caterpillars are about an inch long, slender, and have but two pairs of pro-legs, thus being readily distinguished from the fall canker-worms, with their short third pair of pro-legs (Fig. 84). The spring Fig. 83. — Eggs canker-worm. of the spring Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 81 Fig. 84. — Full-grown spring canker-worms (X l^)- canker-worms vary in color from a light mottled yellowish- brown to a dull black. Their more constant characteristics are a mottled head, a narrow yellow stripe just below the 82 FRriT INSECTS ¥u: So. — spring canker-worm, side view (X 1^)- spiracles, and a wide greenish-yellow stripe bordered by black lines along the middle of the venter (Fig. 85) . Usually 3 narrow, more or less broken, yellow stripes can be distinguished ex- ,4 tending along each side of the body above the spir- acles. By June 1, most of the caterpillars get their growth, spin down from the trees, and enter the ground an inch or more, where they transform in a simple earthen cell to the greenish-brown pupae (Fig. 86). There is but a single generation annually, the insect spending at least 9 months, including the winter, in the pupa stage. Natural enemies of canker-worms. Some of the caterpillars often fall a prey to several hymenop- terous and dipterous (Ta- china) parasites, predatory sucking bugs and ground- beetles. Potter-wasps some- times store their clay nests with them, and other enemies are mentioned in the discus- sion of the fa;ll canker-worm. But by fax' the most effective enemies of canker-worms are the birds. Over forty kinds of birds, especially the chick- adees, thrushes and warblers, have been found feeding on the caterpillars, the eggs or the egg-laden female moths. Yet in spite of the efficient aid thus rendered by the birds and other animal parasites, the cessation Fig. 86. — PuptB of the spring canker- worm. Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 83 of destructive outbreaks of canker-worms is usually due more to certain obscure climatic or other local conditions. Early spring frosts often kill large numbers of the young caterpillars. Remedial measures for canker-wortns. Although among the most destructive of the insect pests of orchards, canker-worms can be rc^adily controlled. Well cultivated orchards are rarely injuriously infested with canker- worms. Thorough cultivation during June or later kills, or turns out for the birds or other enemies, many of the pupse in their earthen cells or cocoons near the surface. Thus orchards can be kept practically free from the devastating hordes of these caterpillars by simply practicing one of the most essential factors in modern fruit-growing ; namely, thorough cultivation. Barriers of various sorts have long been used to prevent their ascent or to trap and kill the wingless female moths when they attempt to crawl up the trunks of the trees to lay their eggs. To get the best results with these barriers it is necessary to know which species of canker-worm infests the trees. If it is the spring canker-worm, the barriers need not be applied until late in February or during March, depending upon the early occurrence of a warm spell. But in the case of the fall canker- worm the barriers must be put on late in October and kept in working order until the ground is well frozen ; in some of the more southern or warmer localities in this insect's range, where many of the moths often do not emerge until early spring, it will be necessary to maintain the barriers during March and April also. Among the mechanical barriers, there are two simple devices that have been found effective. But few of the moths can get over a band of cotton batting several inches wide placed around the trunk, tied tightly with a string near the bottom edge, and the upper portion of the band then turned down over the lower, thus forming an inverted funnel-shaped barrier. When not kept matted down by frequent rains these cotton bands 8i FRUIT INSECTS are very effective. A strip of mosquito wire netting, at least as fine as 16 wires to the inch, and about 14 inches wide, tacked so as to fit tightly around the tree at the top and held out from the bark for half an inch or more at the bottom by a spiral spring or nails driven into the tree, forms almost a perfect bar- rier to the wingless females. We have seen such wire traps nearly full of the moths in badly infested orchards. They should be crushed under the wire each night, and it is sometimes necessary to remove and empty the traps. While these me- chanical barriers may be very effective in preventing the females from getting on to the tree to oviposit, they often lay many eggs below the barriers, and in the case of the wire traps, the young caterpillars may crawl through the meshes and reach the foliage ; the cotton bands, if kept fresh and fluffy, would doubtless continue effective against the caterpillars. In apply- ing such barriers all rough places on the bark must be smoothed or filled so as to allow no chance for the moths to crawl under the edge of the bands. Their effectiveness will depend largely on their proper application and maintenance in a good working condition while the moths are active. Certain sticky band placed around the trunks of the trees are just as effective barriers as the wire traps or cotton bands, and they have the decided advantage of capturing and killing the egg-laden females, and also of effectively preventing the ascent of the young caterpillars that may be hatched below the bands. Among the sticky materials found effective are Tree Tanglefoot, a mixture of 5 pounds resin and 3 pints castor oil (some add Venice turpentine, 3 pints to this) and printer's ink mixed with black Virginia oil or some similar heavy oil to prevent its drying out too quickly. It is best to apply these on a band of tarred or other heavy paper 6 or 8 inches wide tacked or tied around the trunk and all roughnesses beneath filled with cotton. Keep the bands sticky by fresh applica- tions when needed. On badly infested trees it is sometimes APPLE INSECTS — BUDS AND FOLIAGE 85 necessary to renew the bands or apply two, as many of the females may be able to cross the band over the dead bodies and wings of the males, which may completely cover the sticky portion. The use of these mechanical barriers or sticky bands are especially recommended on very large, rough-barked elms, or other trees that it would be difficult to spray or cultivate thoroughly. If no effort is made to prevent the moths from ascending the trees and laying their eggs, either in the fall or spring, the voracious caterpillars can be killed with a poison spray in May. This has been demonstrated many times, but only the most thorough kind of spraying will conquer a hungry army of canker- worms. The most effective work can be done by applying the spray early, when the caterpillars are young and will thus suc- cumb to a smaller dose of poison. Effective work has been done with Paris green at the rate of 1 pound in 100 gallons, but an arsenate of lead spray, 4 or 5 pounds in 100 gallons, has some ad- vantages. For apple trees make one application just before the blossoms open and a second after the petals fall ; if the work is thoroughly done, further applications will be rarely necessary. For shade trees, begin spraying as soon as the first leaves un- fold or the young canker-worms are seen, which is usually early in May. Under the modern system of fruit-growing, embodying thorough cultural and spraying methods, canker-worms will rarely find congenial conditions for their nefarious and destruc- tive work ; in fact they now seldom attract the attention of commercial growers. References Peck, Nat. Hist. Canker-worm. 1796. Harris, Insects Inj. Veg. pp. 332-343. 1841. Ohio Dept. Agr. Bull. 2. 1903. U. S. Bur. Ent. Bull. 68, Pt. II. 1907. Conn. Agr. Exp. Sta. Rept. for 1907-1908, pp. 777-796. 1909. 86 FRUIT INSECTS The Fall Canker-worm Alsophila pometaria Harris Although not distinguished from the spring canker-worm until 1873, this fall canker-worm doubtless has been injurious in the New England states for half a century or more. It is now common in Canada and throughout the northeastern United States, extending west- ward into Ohio ; and in 1891, orchards of apple, prune, plum, apricot and cherry were ravaged in western California, ap- FiG. 87. — Fall canker-worm, male moth ( X 2) . parently by this eastern fall canker-worm. It is often de- structive in apple orchards, some- times working with the spring canker-worm or on neighboring orchard or shade trees ; the two species have worked separately* for several years on elm trees about a mile apart near Ithaca, N. Y. The fall canker-worm is easily distinguished in all its stages from the spring species, and differs also in its life-habits. It derived its common name from the fact that the moths usually emergen and lay their eggs in the fall, mostly in November; often a few, however, Fig. 88. — Fall canker-worm, male moth (X2|). fe- APPLE INSECTS— BUDS AND FOLIAGE 87 and sometimes many, of the moths do not emerge until spring. The male moths are about the same size and resemble much those of the spring canker-worm, but their wings are of a darker smoky or brownish-gray color ; the fore wings Fig. 89. — Fall canker-worm moths laying eggs. Knight photo (X 2). Fig. 90. — Portion of an egg-mass of the fall canker-worm, greatly enlarged. have a distinct whitish spot on the front edge near the tip (Fig. 87). The wingless female moths are nearly J an inch in length and of a uniform brown- ish-ash color (Fig. 88). There are no spines on the bodies of either the male or female fall c a n k e r-w o r m moths. The dark grayish eggs re- sem])le tiny flower-pots or in- ■piG. 91.— Eggs of verted truncated the fall canker-worm, cones, the flat- side view, greatly en- larged. tened steel-gray Fig. 92. — Fall canker-worm, full-grown caterpillar (X 2). 88 FRUIT INSECTS Fig. Fall canker-worms (Xl|). top marked by a darker ring and central spot (Figs. 90 and 91). They are laid in exposed positions on the bark (Fig. 89), mostly on the twigs, in flattened masses of from 100 to over 400, and are set close together on end in quite regular rows. The eggs hatch in April or May when the buds are opening, and the caterpillars work on the foliage for about a month in the same manner as the spring canker-worms. The full-grown fall canker-worms are about an inch in length, slender, of a general black color with the venter and all the legs light apple green (Figs. 92 and 93). Just below the spiracles there is a stripe of light lemon yellow, and above them on each side of the body are three nar- rower whitish stripes. There are 3 pairs of pro-legs, but the first pair are much smaller and are not used when the caterpillar loops or spans in walking. About June 1, most of the caterpillars spin down from the trees and enter the ground from 1 to 4 inches, where they con- struct a thin but dense and tough silken cocoon in which the greenish- brown, somewhat tender pupae (Fig. 94) remain until November, or sometimes until the next spring. There is only one brood annually. Fig. 94. — Pupse of fall canker- worm. Enlarged. APPLE INSECTS — nUDS AND FOLIAGE 89 Natural enemies. The eggs are sometimes devoured by a mite, Nothrus ovivorus, or a minute parasitic chalcid fly may develop in them. The chickadees often find many of the eggs or the egg-laden female moths on the bark. The caterpillars are attacked by a Tachina fly, and the same ground beetles and birds that devour the caterpillars of the spring canker-worm also include this species in their menu. Remedial measures. The remedial treatments for the fall canker-worm are the same as recommended for the spring canker-worm, ])ut the sticky band or other barrier for preventing the ascent of the wingless female moths must be applied in the fall, in October, and kept in working condition until December, then renewed in Febru- ary or March to get the belated ones that may not emerge until spring. Further details regarding the habits, natural enemies and remedial treatments for this species, will be found in the pre- ceding more extended account of the spring canker-worm. The Lime-tree Span-worm Erannis tiliaria Harris This native American insect is widely distributed and com- mon in apple orchards, and on basswood, elm and other forest trees. It often works with both the spring and fall canker- worms in orchards, but is rarely so numerous and injurious. The moths appear in November and are active at night only. The practically wingless, yellowish-white females, nearly § an inch long, are marked with two rows of black spots down the back (Fig. 95). The light, rusty buff-colored front wings of the male moth expand about IJ inches and are crossed by two nar- row, wavy, darker stripes; the hind wings are much lighter 90 FRUIT INSECTS (Fig. 96). The females crawl up the trees and lay their oval, light greenish- yellow, finely pitted eggs (Fig. 97) from 1 to 5 in a place tucked away out of sight beneath the scaly bark or in crevices on the trunk and larger limbs. The eggs hatch in early spring, often in April, and some of the caterpillars continue feed- ing until nearly the middle of June. When full-grown they are nearly IJ inches long and the skin has a rough velvety appearance. The head is rusty red in color and much roughened. Along the back extend 10 narrow, crinkly, black stripes separated by similar light yellow stripes, the yellow rarely predominating. A broad lemon yellow stigmal stripe extends along each side, and the underside of the body, including the two pairs of pro-legs, is light yellow- ish-white in color (Fig. 98). Fig. 95. — The lime-tree span-worm, female moth (X 3|). Fig. 96. The lime-tree span-worm, male moth. Fig. 97. — Eggs of the lime-tree span- worm. Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 9l Fk;. !»S. — Three views of the lime-tree span-worm eiiterpillar (X Ip. Early in June the caterpillars are quite restless, and finally go into the ground an inch or more, where they transform to brown pupae (Fig. 99) in simple, earthen cells. Some of them pupate in May. There is but a single generation annually, the pupa stage continuing until November. 92 FRUIT INSECTS Fig. 99.— Pupa of the lime-tree span- worm. En- larged. Birds, especially the bluejay, get many of the caterpillars. The fiery and rummaging ground- beetles {Calosoma calidum and scrutator) also climb the infested trees and capture them. Remedial treatment. As its habits and life history are similar to those of the fall canker-worm, this lime-tree measuring-worm can be controlled by the same barrier and spraying methods. About a week before they go into the ground to transform, these large caterpillars are very restless and often either drop or are blown from the trees to the ground. In their wanderings and attempts to get on to the trees again, many have been caught in the wire-screen barriers applied earlier to pre- vent the ascent of the spring canker-worm moths. The Mottled Umber-moth Era) mis defoliaria C'lerck This common and destructive European orchard pest has established itself in British Columbia, and since 1893 it has been more or less destructive in plum and cherry orchards. The caterpillars are general feeders on various fruit and shade trees and often gnaw into unripe cherries in England. The life history and habits of this mottled umber-moth are very simi- lar to those of the American lime-tree span-worm, the moths emerging in November and the caterpillars working in June and early July in British Columbia. The European insect differs but little from the native species. The wingless females are brownish with rows of brown instead of black spots, and the dull ochre-brown front wings of the males are crossed by two wider dark waved bands, while the APPLE INSECTS — BUDS AND FOLIAGE 93 pale hind wings as well as the front ones are mottled with brown dots. Descriptions and figures of the caterpillars indicate that they are much like the lime-tree span-worms ; the dorsal region is described as reddish-brown instead of yellow between the black stripes and the spiracles are in the (;enter of blotches of reddish-brown. A Tachina fly parasite is killing some of the caterpillars in British Columbia. This imported pest will doubtless succumb to the same remedial treatment as the native species. Bruce's Measuring-worm Rachela bruceata Hulst This insect was first described from western New York in 1886, where a few years later it was quite injurious in apple orchards and on maple trees. Millions of the caterpillars ap- peared in Alberta, Canada, in 1902, and the following year hundreds of acres of American aspen or poplar trees were de- nuded in June. The moths have been found in British Columbia also. The wingless female moths are about one third of an inch long, light brownish-gray, and closely resemble the females of the fall canker-worm, differing in being only about two thirds as large and in having slightly longer stubs of wings (Fig. 100). The winged male moths have a wing expanse of about 1| inches and are of a general very pale brownish color, the wing veins Fig. 100. — Bruce's measuring-worm, female moth (X 4). 94 FRUIT INSECTS being quite distinctly outlined by darker scales (Fig. 101). The moths emerge and go up the trees for egg-laying at night in October and November. The reddish-orange, oval, finely pitted Fig. 101. — Bruce's measuring-worm, nial ' Fig. 102. — Eggs of Bruce's moth (X 12)- measuring-worm. Enlarged. eggs (Fig. 102) are usually laid singly where readily seen in the crevices of bark scales on the trunk and larger branches (Fig. 103). The eggs hatch in April, or as soon as the buds begin to open. The young canker-worms often bore into the buds and continue feeding for 4 or 5 weeks. They seem to be par- ticularly fond of the opening flower buds on apple, and thus often ruin a prospective crop. The full-grown Bruce's canker-worms are about f of an inch long and of a general apple green color, with three narrow yellowish-white stripes along each side of the body (Fig. 104). There are two pairs of pro-legs, and the head, thoracic and anal shields, and a large spot on the anal pro-legs, Fig. 103. — Eggs of Bruce's measur- ing-worm tucked behind a bit of lichen on a tree trunk. Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 95 are usually blackish, but sometimes nearly concolorous with the body in lighter colored specimens. Fig. 104. — Bruce's measuring-worm, full-grown eatorpillars, slightly onlargcd. By June 1, and sometimes a month before in earlier seasons, these canker-worms all enter the ground a short distance, and 96 FRUIT INSECTS in a slight silk-lined cocoon (Fig. 105) they soon transform to light brown pupa^ (Fig. 104) from which the moths do not emerge until autumn. Like the other kinds of measuring-worms known as can- ker-worms, there is thus but a single gen- eration of this species annually. It ap- FiG. 104 a.— Pupa of Bruce's measuring-worm. Enlarged. Fig. 105. — Cocoon of Bruce's measuring-worm. parently gets through with its destructive work a little earlier in the spring than the other canker-worms, and evinces a special fondness for the blossom buds. It can be controlled by the remedial measures recommended for the fall canker-worms. The Half-winged Geometer Phigalia titea Cramer About 1898 several kinds of canker-worms devastated apple orchards in western New York, and among them was this species, which we have designated the half-winged canker-worm, be- cause of the nearly half developed condition of the wings of the female moths. The insect is widely distributed from New York to Minnesota and includes among its food-plants, apple, black- berry, rose and several forest trees. It is rarely very numerous, APPLE INSECTS— BUDS AND FOLIAGE 97 but the peculiar cjiter- pillars and female moths often attract the atten- tion of the orchardist. The male moths are pale ash gray with 3 blackish- brown, narrow, trans- verse stripes across the front wings which expand nearly \\ inches ; the an- tennae are strongly pec- tinated (Fig. 106). The females are about Fig. 106. The half-winged geometer, male moth (X Ij). of an inch long, the hind wings reach to the second abdominal segment, and the body is clothed with a mixture of black, brown and white scales, the lighter scales predominating on the wings and underside (Fig. 107). The moths emerge and go up the trees at night in March and April, and one fe- male may lay 600 eggs. The slightly egg-shaped greenish eggs have a firm shell covered with a net- work of fine ridges form- ing 6-sided areas (Fig. 108). The caterpillars are full-grown about the middle of June, when they are about l\ inches long, and of a general violaceous-brown color with a rough, black- mottled head. Eight pairs of narrow, irregular, black stripes extend along Fig. 107.- ■The half-winged geometer, female moth (X 2|). 98 FRUIT INSECTS the body (Fig. 109), the four pairs on the underside being less distinct and ending at the first of the two pairs of pro-legs. The hair-bear- ing spots are elevated into shining black papillae, those in the hind row on the first four abdominal segments being considerably larger. These canker-worms pupate (Fig. 110) late in June in simple earthen cells in the soil, and the single annual life-cycle is completed when the moths emerge in autumn. Fig. 108. — Eggs of the half-winged geometer. Enlarged. Fig. 109. — Caterpillars of the half-winged geometer (X 1|). Fig. 110. — Pupa of the half- winged geometer. Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 99 This half-winged canker-worm will rcuidily siiccniml:) to the same remedial treatments as advised for the fall canker-worm. The White Ennomid Ennomos subsignarius Hiibner This common and widespread measuring-worm often strips various forest trees and shrubs, and it has also defoliat(Hl apple orchards in Georgia and Kentucky. The moths are snow-white, with a wing-expanse of about 1| inches ; the males have strongly pectinate antenna?. It is said that if a bird alights in a tree where the moths are numerous, they suddenly drop like snow- flakes to the ground for protection. The caterpillars also drop at the slightest jar and swing in the air by their silken threads. They are about If of an inch long, of a reddish-black color and have two pairs of pro-legs and three pairs of small tubercles on the back. The caterpillars transform through oddly granu- lated, brown-dotted pupae to the moths in about 10 days in May or June in one or more leaves rolled or loosely fastened together. The snow-white moths appear mostly in June and lay their pouch-shaped, greenish-olive eggs in large patches of a hundred or more on the undersides of the upper branches of the trees. The eggs are set on their rounded ends, the top being cut off rather squarely and marked with a narrow, white, oval ring surrounding a darker area. There is but one genera- tion annually, and about 9 months are spent in the egg stage, the eggs hibernating and hatching in April or May. This measuring-worm can be readily controlled in orchards by thoroughly spraying the trees in May when the caterpillars are small with arsenate of lead, 5 pounds in 100 gallons of water. Reference Cornell Agr. Exp. Sta. Bull. 286. 1910. 100 FRUIT INSECTS The White-marked Tussock-moth Hemerocampa leucostigma Smith and Abbot There are three species of these tussock-moths that may injuriously infest orchards. Two of these are native American insects and one is an old and common European species. Fig. 111. — Caterpillar of the white-marked tussock-moth, full-grown (Xls)- With their many hairs arranged in striking pencils, tufts and tussocks or brushes, the caterpillars of the white-marked tussock-moth present a very handsome and characteristic appearance (Fig. 111). They are about 1| inches long when full-grown and of a general dark gray color with a broad vel- vety black band bordered by yellow stripes on the back and a similar yellow stripe along each side below the spiracles. The head, thoracic shield and two raised glands on the back of the 6th and 7th abdominal segments are bright vermilion-red. Their striking characteristics are dense, brush-like, cream- colored tufts or tussocks of hairs on the back of each of the first APPLE INSECTS — BUDS AND VOLTAGE 101 Fig. 112. — Pupae of the white- marked tussock-moth. Enlarged. four abdominal segments, and pencils of long plume-tipped black hairs projecting from each side of the first thoracic segment and from the back of the eighth abdominal segment. These strikingly beautiful caterpillars are common in orchards, espe- cially on apple, pear, quince and plum trees, in Canada and over the eastern half of the United States. Considerable injury often results from their work on the foliage in orchards, and in one case 25 per cent of the apples were ruined by the caterpillars gnawing into the sides. But the insect often be- comes a far more de- structive and formidable pest in cities and towns on shade trees, especially the horse chestnut, pop- lar and elm. In the North there is l)ut a single annual brood, but in southern New York and southward there are two or three broods. The caterpillars feed mostly from the un- derside of the leaves dur- ing June, and in July they transform to pupae (Fig. 112) in their silken cocoons, in which their long hairs are inter- FiG. 113. — Female white-marked tussock- moths depositing egg-masses on cocoons. 102 FRUIT INSECTS Fig. 114. woven, on the bark in the crotches of the trees or on fences or houses near by. In about two weeks the moths emerge. The hairy, grub-hke, light-grayish females have mere stubs of wings, and usually remain on their empty cocoons until after they mate and lay a mass of from 150 to over 700 eggs thereon (Fig. 113). The nearly spherical, yellowish- white eggs are covered bj^ a mass of conspicuous white, ,______-__,,_ frothy material. The ashy- mM T^^^M^^ grsij colored male moths have ^^m|hHK feathery antennae and well ^^^^^^ developed wings, which ex- ^^W panel about If inches (Fig. ,114). The front wings are — Male white-marked tussock- moth, crossed by undulated bands of darker shades and bear a conspicuous white spot near the anal angle, hence the name leucostigma or white-marked. The winter is always passed in the egg stage, the caterpillars hatching late in May in New York. Natural enemies. This tussock-moth is beset by many enemies. At least 10 different birds eat the caterpillars and doubtless do much to keep the insect in check in orchards and the open country. Several species of shield-bugs and the southern wheel-bug attack the caterpillars and pupae ; the pupae are also eaten by small red ants. The grubs of two Dermestid beetles and a species of mite may devour the eggs. And as niany as 90 per cent of the caterpillars and pupae sometimes fall a prey to more than 20 different kinds of hymenopterous and dipterous in- sect parasites, the most effective of these little enemies being Pimpla inquisitor, Chalcis ovata, Tachina rnella, Frontina frenchii, APPLE INSECTS — BUDS AND FOLIAGE 103 and Euphorocera daripennis. Unfortunately, however, there are 14 hyper-parasites which work on the true parasites and thus materially lessen their effectiveness. There are also ter- tiary parasites which destroy these hyper-parasites, thus pre- senting a very complicated and interesting case of insect parasitism. Remedial measures. A practicable and effe(;tive method of controlling this pest is to collect and burn the eggs in autumn or winter. The grayish egg-masses are quite conspicuous on the bark and they are often attached to a dead leaf or two fastened to the branches. Where shade trees are infested in cities, it will pay to employ laborers to collect the eggs, and sometimes the school children can be induced to do very effective work by offering prizes or by paying liberally for certain quantities of the egg-masses. The latter method was employed successfully several years ago in Rochester, N. Y., during a severe outbreak of the pest. Before they are half-grown the beautiful caterpillars will succumb to thorough applications of a strong poison spray, such as Paris green (1 pound in 100 gallons) or arsenate of lead (5 or 6 pounds in 100 gallons). One or two applications of such a spray will usually control this pest. Later when the caterpillars are larger, the poison is not so effective. As the caterpillars drop to the ground by a silken thread when the tree is jarred, some orchardists have found it practicable to capture them on cur- culio-catchers or sheets. Or after jarring them off, they can be prevented from ascending the trees by means of a sticky rope band around th(^ trunk. Treat the rope with a tangle- foot mixture of resin and (uistor oil, as recommended for canker- worm bands. References U. S. Bur. Ent. Tech. Bull. 5. 1897. Parasites. U. S. Farmers' Bull. 99, pp. 14-31. 1899. Del. Agr. Exp. Sta. Bull. 56, pp. 9-18. 1902. N. Y. (Geneva) Agr. Exp. Sta. Bull. 312. 1909. 104 FEUIT INtiECTS The California Tussock-moth Hemerocanipa vetusta Boisduval This native California tussock caterpillar has been recorded only from that state, where it is common on live oak and yellow lupin trees, and has injuriously infested apple and cherry or- chards. There is but a single brood annually, the moths appear- ing in May, June and July and laying their eggs on their empty cocoons in light grayish masses covered with hairs from the mother's body. Some of the egg-clusters hatch as early as February, while others may not until April or May. The cater- pillars feed on the foliage from one and a half to two months. They have black heads, crimson hair-bearing warts and pro-legs, and the four tussocks or })rush-like tufts of hairs on the back are often dark gray with brownish crests. The practically wingless grub-like female moths have dark brown bodies covered with sordid white hairs. The males resemble those of the antique tussock-moth but are of a darker chestnut-brown color. The general life-habits of this California tussock-moth are similar to those of the two eastern species. Natural enemies. Tachina Hies and other parasites sometimes de\stroy half of the caterpillars and pui)ie, but the birds do not seem to eat them to any extent in (California. The grubs of a Dermestid beetle devour some of the eggs, and others are parasitized by a minute hymenopt{nx)us ins(M^t, Telenornus orgyice. Reniedia I treatme nts . Poison sprays an* rej)()rled as not very effective against the caterpillars in California, the older ones after eating poisoned foliage being able to transform to the moths. The measures recommended are the collecting and destroying of the eggs during the winter season, and the })eating or jarring of the caterpillars from the trees, then preventing their ascent with APPLE INSECTS — BUDS AND FOLIAGE 105 sticky rope bands, as described for the white-marked tussock- moth. Reference . Cal. Affr. Exj). St a. l^iill. lS;i. 1907. The Antique Tussock-moth Notolophus antiqua Linmeus This common European pest has been more or less injurious in America on shade trees and in orchards for nearly a century. It is often seen in Nova Scotia, the New England states and also occurs as far westward as Washington. The caterpillars resemble those of the white- marked tussock- F^«- 115- - The antique tussock-moth, full-grown caterpillar. moth, but the head is black, and the first two tussocks or brushes of hairs on the back are black on the young caterpillars, but become whitish in later stages (Fig. 115) After the third stage there is also an additional pencil of long, black, plume-tipped hairs pro- jecting from each side of the second abdominal segment. In its life history this species differs ])ut little from that of the white-marked tussock-moth. There is a single brood annually in its northern range, the eggs hibernate, but there is no covering on the egg-masses laid on the cocoons. In Eng- land it is said that a few of the eggs hatch at a time over a period of 10 weeks, but they seem to hatch uniformly in America. The gru})-like, practically wingless female moths have blackish l)odies covered with yellowish-white hairs. The males have rust-brown colored wings, the front ones being crossed by two 106 FRUIT INSECTS deeper brown bands and having a very conspicuous white spot near the anal angle. This antique tussock-moth is attacked by many of the same enemies as the white-marked tussock-moth, and it can be con- trolled bv the same remedial measures. The Oriental Moth Cmdocampa flavescens Walker This is an Asiatic insect which was apparently introduced into Massachusetts on nursery stock from Japan some time before 1900, but its presence was not discovered until February, 1906. One of the peculiar cocoons of this moth has also been found in an Albany, New York greenhouse on imported Japanese maples. It seems to prefer to feed on the foliage of Norway maples, but pear, apple and cherry are often infested, and it includes a dozen other shade and forest trees among its food- plants. The yellowish-red, slug caterpillars are armed with rows of spiny tubercles or horns, and are about f of an inch long. They hibernate in curious tough, smooth, oval-shaped cocoons, a little more than J an inch in length, fastened firmly to the bark, mostly on the smaller branches in or near the axil of a branch. The cocoons are strikingly colored, with whitish and brown often so mingled as to suggest certain oriental designs. There is a brown lid at one end which is pushed open by the pupa late in June when the moth emerges. There is but one brood annually, the cocoons being made in September or Octo- ber. The pretty moths have a wing expanse of nearly IJ inches, the head, thorax and inner half of the front wings above being of a dull chrome yellow color, while the upper portion of the outer half is hght chestnut brown with a yellowish tinge and the lower half is tinged with pink. While the oriental moth belongs to a family, the Cochlidiidse, APPLE INSECTS — BUDS AND FOLIAGE 107 the members of which are not usually of economic importance, its natural enemies probably were not introduced with it into this country, and it is maintaining itself and slowly spreading in Massachusetts. Judging from its range in Asia, the insect can live almost anywhere in the United States as far as climate is concerned. Whether it ever becomes a serious pest in America, especially on fruit trees, only the future can reveal, but the probabilities are that it will not. The caterpillars will doubtless succumb to a thorough appli- cation of a strong poison, like arsenate of lead, 4 pounds in 100 gallons of water, and it would be practicable to prune off and destroy the curious cocoons in winter or early spring on small trees. Reference Mass. Agr. Exp. Sta. Bull. 114. 1907. The Fall Webworm Ilyphantria canea Drury The unsightly nests of this caterpillar an; familiar objects in late summer on a large number of forest and shade trees (Fig. 116). Economically this insect is of greater importance as a shade tree pest in cities than as an enemy of fruit trees, but occasionally its attacks on appk; and pear are sufficiently severe to cause considerable loss. It feeds on over one hundred differ- ent trees and is distributcnl over the Eastern states from Georgia and Texas to Montana and Canada ; it also occurs in Califor- nia. In the North, wIhtc only one generation develops annually, it only occasionally causes s(Tious injury to fruit trees, but from southern New York southward, where there are two full generations, orchards are sometimes completely stripped of their leaves. In the South it sometimes becomes a serious enemy of the pecan. The winter is passed by the reddish-brown pupae, i inch in 108 FRUIT INSECTS length, in thin cocoons placed in crevices of the bark, under trash, or just beneath the surface of the ground. The emer- gence of the moths extends over a considerable period, from early June until the middle of August in New York. The webs begin to become conspicuous in July and are most abundant in August (Fig. 117). In the District of Columbia the first brood of moths ap- pears soon after the leaves are fully de- veloped ; that is, about June first, the second brood occur- ring in July and August. The moths expand about IJ inches and vary in color from satiny white to whitc^ heavily spotted with })lack or brownish spots. Some of these forms have received specific names, but it is now generally l)elieved that we have only one species which is highly vari- able. More recently Dr. H. H. Lyman has attempted to separate two forms on the color of the larvae, but the evidence presented is hardly convincing. More extensive rearings are greatly needed. The moth lays her pale green eggs in clusters on the upper or under surface of the leaves, and covers the cluster with white hairs from her body (Fig. 118). The cluster is about f inch Fig. 116. — Fall wobworm, beginning of a nest. APPLE INSECTS — BUDS AND FOLIAGE 109 Fig. 117. Fall webworm, nest. in diamder and contains 300 or 400 ('ggs. The egg is globular, 5V ii^^'^^ i^^ diameter, and has a deli(*at(^ thimble- like sculpture. The eggs of the first brood hatch in about 10 days and those of the second in jd)()ut a week after deposition. Soon after hatch- ing the extremely hairy young cater- pillars begin feeding on the leaves, usually at the end of a branch, which they inclose in a silken web. At first they feed only under cover of the web, which is enlarged to inclose more foliage as there is need of fresh food. When the caterpillars become larger they leave the nest at night and feed in the open. As food becomes scarce on a branch, all or part of a colony may migrate to another branch, where a new nest is formed, or in case the whole tree has been de- foliated, they may crawl to another tree. The full-grown caterpillars (Fig. 119) are about li inches in length with a broad dusky stripe along the back and usually with yellowish sides thickly spotted with small blackish dots. A 118. — The fall webworm, moth laying eggs. 110 FRUIT INSECTS Fig. 119. — Full-grown fall webuu.iu raL^ipiiiais. Slightly enlarged. APPLE INSECTS — BUDS AND FOLIAGE 111 darker form occurs in which the yellow on the sides is entirely obscured, and the whole caterpillar is of a dull dusky color, but all gradations are found. Natural enemies. Few birds feed on these hairy caterpillars to any great extent. Among predaceous insects their most important enemies are the Mantis (Mantis Carolina) and the wheel-bug (Prionidus cristatus), both abundant in the South. Of true parasites the most important are Telenomus bifidus Riley, attacking the eggs, Meteorus hyphantrice Riley, Apanteles hyphantrioe Riley, and Limneria pallipes Prov., attacking the cater- pillars. Good work is also done by an unnamed Tachinid-fly. Unfortunately the efficiency of this series of parasites is greatly lessened by the great number of secondary parasites, which prey upon them. Under favorable conditions great numbers of the caterpillars are killed by a fungous disease, Empusa grylli. Remedial measures. In the forest we must depend on its natural enemies to hold this pest in check. On shade trees in cities spraying with an arsenical poison and a thorough and timely removal of the small webs while the caterpillars are still young will do much to prevent serious damage. Especial attention should be given to the destruction of the first generation, thereby lessening the difficulty of controlling the second. In orchards where arsenical spraying is regularly practiced most of the first brood of caterpillars will be destroyed. The webs should be cut out or burned out with a torch as soon as observed. This can be done most easily while they are small and before any large branches have been included in the nest. The webs should be destroyed during the day while practically all the caterpillars are within. References Riley, Rept. U. S. Com. Agr. 1886, pp. 518-539. Lyman, 32d Rept. Ent. Soc. Ont., pp. 57-02. 1902. 112 FRUIT INSECTS Del. Agr. Exp. Sta. Bull. 56. 1902. Felt, Forest Insects, I, pp. 142-146. 1905. Berger, U. S. Bur. Ent. Bull. 60, pp. 41-51. 1906, The Apple-tree Tent-caterpillar Malacosorna americana Fabricius The unsightly nests (Fig. 120) of this caterpillar are con- spicuous objects on wild cherry trees and in neglected orchards. Fig. 120. — The nest of the apple-tree tent-caterpillar. This species occurs in the Eastern states and Canada, ranging westward to the Rocky Mountains, where it is replaced by other forms. It occurs sparingly in California. Its favorite food APPLE INSECTS— BUDS AND FOLIAGE 113 is the wild cherry, although it will attack apple, peach, plum, and more rarely, witch-hazel, beech, birch, barberry, oak, willow and poplar. When excessively abundant apple trees are frequently completely defoliated and killed (Fig. 121). Destructive outbreaks usually continue for two or three years Tree tlcfoliatcd by apph^-trcc tent-caterpillars. only and are then followed l)y a longer j)eriod during which the species is rarely noticed. This periodic fluctuation is thought to be the result of complicated interrelations existing between the caterpillar and its parasites, and is a striking illustration of the ups and downs of insect life. lU FRUIT INSECTS The winter is spent in the egg stage, al- though the embryo is fully developed in the fall. The eggs are elongate, thimble- shaped, about 2T ii^ch long and are laid in masses of over 300 to 400, usually encircling a small branch as a broad band (Fig. 122). The whole egg-mass is covered by a brownish gluey froth, which it from the About the time the first buds open the eggs hatch and the young larvie begin to feed on the opening leaves. The larvse are Fig. 122. — Egg-mass of the apple- tree tent-cat- protects erpillar cut , open to show Weather. eggs. Fr 124. — Cucoous of the uppk'-trec tent-caterpillar ( X f ) . Fig. 123. — Full-grown apple- tree tent-caterpillars (x 1^). social, and all those from a single egg-cluster remain together and soon begin a tsilken nest. Sometimes when two egg-masses APPLE INSECTS — BUDS AND FOLIAGE 115 are placed close together the two colonies unite in forming a common nest. The n(^st is at first small, but gradually enlarges as the cateri)illars grow larger, until in sonic cases it may be nearly two feet in length. During storms and the heat of the day the caterpillars usually remain within the nest, coming out to feed early in the morning, in the Mr- \ Fig. 12G. — Male moths of the apple- tree tent-caterpillar. Fig. IL'."). — - Pupse of the apple-tree tent-caterpillar (x 3). evening, or at night when it is not too cold. The full- grown caterpillar is about two inches long, black with a light stripe down the back and with dots of blue and white along the sides, and is clothed wdth fine, soft, yellowish hairs (Fig. 123). When nearly full-grown they wander from the nest, and after feeding for a few days more crawl to some protected place and spin their cocoons. The oval, w^hite cocoons are about one inch in length (Fig. 124) . They are made of tough, closely woven, white silk, and are held in place by a few irregular coarser threads. The 116 FRUIT INSECTS newly made cocoon is dusted over with a yellowish powder. A few days after finishing the cocoon the larva transforms into a brownish pupa, f to f inch in length, which is clothed with a brownish pubescence except on the sheaths of wings and legs (Fig. 125). The pupal period lasts about three weeks. Fig. 127. — Male and female moths of the apple-tree tent-caterpillar. In New York the majority of the moths emerge during the last week of June and the first week of July, and the eggs are laid soon after. There is but one generation a year, from July till April being spent in the egg stage. The moths are dull, reddish-brown, marked on the front wings by two nearly parallel oblique whitish lines (Figs. 126 and 127). The females expand 1 J to 2 inches ; the males are slightly smaller and of a darker brown. Natural enemies. The tent caterpillar is held in check b}^ a long series of para- APPLE INSECTS — BUDS AND FOLIAGE 117 sites which prey upon it in the egg, hirval and pupal stages. This control is so effective that for many years the insect is rarely noticed. Then the time comes when, owing to the rarity of the host, the parasites are reduced in numbers to a still greater degree, and the caterpillars again have an opportunity to multiply unchecked. The resultant outbreak may be very serious, as was the case in New York and New England in 1897 and 1899. Four species of parasites have been reared from the egg and over 20 from the larva and pupa. Birds and toads also feed on the caterpillars to a considerable extent, and many nearly full-grown larvae die of a bacterial disease. Means of control. In orchards which are well sprayed as for the codlin-moth and curculio, tent-caterpillars are rarel}^ troublesome. The young larvae are readily poisoned by either Paris green or arsenate of lead. On peach and plum, which are not commonly sprayed with an arsenical, it will pay to keep careful watch for the conspicuous egg-rings while pruning. They should be re- moved and burned. The nests may be destroyed l^y wiping out with the hands. It should be done while the caterpillars are at home, which is usually the case during stormy weather and in the heat of the day. Burning out the nests is not to be recommended as there is danger of injuring the tree ; burned areas in the bark often develop cankers that may destroy the whole branch. The wild cherry is the favorite food-plant of this insect. When growing along roadsides and fences and in other waste places these trees are usually worthless and should be cut down, as they serve as centers of infestation for near-by orchards. References N. Y. (Geneva) Agr. Exp. 8ta. Bull. 152, pp. 279-297. 1898. Conn. Agr. Exp. Sta. Bull. 131). 1902. N. H. Agr. Exp. Sta. Tech. Bull. 0. 1903. Parasites. 118 FRUIT INSECTS The Western Tent-caterpillar Malacosoma fragilis Stretch From the Rocky Mountains westward the apple-tree tent- caterpillar is replaced by a number of forms all very much alike in habits and in the form and coloration of the moths. The caterpillars, however, are different. From the Rockies to the Sierras and from Mexico to Canada the dominant form is M. fragilis. It forms a web like its eastern rela- tive and has a similar life history. In Colorado the larvae become full-grown by July 1, and the moths emerge and lay their eggs during the latter part of the month. The full-grown larva is similar to the Western tent-caterpillars. . /• u x • i eastern lorm but is pale blue or blue-gray on the sides, and the median line has a row of bluish spots instead of the whitish line (Fig. 128). The species is single })rooded. The larvae feed on apple, wil- low, poplar, wild cherrj^, wild rose and wild gooseberry. Control. The same remedial measures are suggested for this species as for the apple-tree tent-caterpillar. Another species, Malacosoma pluvialis Dyar occurs in the Pacific Northwest. Very little is known concerning it except that in habits and life history it does not differ greatly from the other species. Reference Ore. Agr. Exp. Sta. Bull. 313. 1894. APPLE INSECTS — BUDS AND FOLIAGE 119 The Forest Tent-caterpillar Malacosoma disstria Hiibner The common name of this species is a misnomer, for the cater- pillars do not construct a true tent, as in the case of the pre- ceding species. It is closely related to the apple-tree tent- caterpillar, and has a similar life history, but its habits are decidedly different. Its range extends throughout the United States and Canada and it has been reported from Mexico. It is naturally a forest in- sect, the maple being its favorite food plant. When unusually abun- dant, however, it attacks a large number of trees and shrubs, and in the orchard feeds on the apple, plum, peach, Fig. 129. — Egg-rings of the forest tent-cater- cherry and pear. Severe pillar, outbreaks occur at rather long intervals and usually last for only two or three years. In 1898 and 1899 a very extensive and severe outbreak occurred in New York and New England ; the caterpillars de- foliated thousands of acres of forest and did great damage in fruit orchards. They also appeared in destructive numbers in 1912 and 1913. The winter is passed in the egg stage (Fig. 129). The eggs hatch in early spring and the young caterpillars feed in colonies on the opening heaves. They leave a silken thread wherever they go and in this way the colony frequently webs in some of the leaves where they are feeding. These slight webs are not true tents ; they are n(;ver entered by the caterpillars and are not used for protection. When not feeding or when preparing 120 FRUIT INSECTS for molting the larvae congregate in masses on the branches or trunk (Fig. 131). When the caterpillars become nearly full-grown they become restless and wander away to feed singly for some days. The full-grown cater- pillar is about two inches long and is easily distinguished from the apple-tree tent-caterpillar by having a median row of wedge- shaped or club- shaped cream-col- ored spots instead of the continuous median whitish stripe i^resent in that species (Fig. 130). On the ab- dominal segments these spots are broken into two un- equal parts, which gives them the ap- pearance of a row of exclamation marks. In New York the caterpil- lars become full- grown in late May and early June, dep(niding on the season. The cocoons are made of white silk, the outer layers being Fid. 130. — Full-grown forest tent-caterpillar.s (X Ig) APPLE INSECTS — JWDS AND FOLIAGE 121 soft and fluff}^ and dusted with a yellowish powder (Fig. 132). Most of the cocoons are placed in curled leaves, but many are found in other more or less protected situations. In New York the moths (unerg(^ and lay their eggs the last week of June and the first of July. T\\v moths are similar to those of the apple- tree tent-caterpillar, but th(^ oblique bands across the fi-ont wings are brown instead of whitish (Fig. 133). The eggs closely resemble those of that species, but the egg-rings are smaller and more abruptly rounded off at the ends. Eacli egg-mass contains from 150 to over 400 eggs. The young cater- pillar becomes fully formed by the end of August but remains within the egg until the follow- ing spring. Natural enemies. The caterpillars are preyed upon by several kinds of birds and by toads. Two predaceous beetles, Calosoma scrutator Fab. and C. calidum Fab., feed on the larvae as do two of the sucking bugs, Podisus placidus Uhler and P. serieventris Uhler. A num})er of hymenopterous and dipterous parasites prey on the cater- pillars and are valuable aids in holding the pest in check. The most important of these are, Pimpla conquisitor Say, Pimpla inquisitor, Anomolon exile Pro v., Tachina mella Walk. A mite also destroys the eggs. Fig. 131. — A mass of forest tent- eaterpillars resting on a tree trunk. 122 FttniT INSECTS X ^i i Fig. 132. Cocoons of the forest tent-caterpillar. Methods of control. In the forest little can be done to fight this insect. As a shade tree pest in villages and cities spraying with arsenate of lead, 8 pounds to 100 gallons of water, while the larvae are still small, would be effective. The cocoons should be collected when- ever found and placed in a box covered with -^ inch mesh screen, which will permit the escape of the parasites while retaining the moths. In some towns children have been hired to collect the Fig. 133. -Female moth of the cocooiis at ten cents a quart with forest tent-caterpillar. excellent results. APPLE INSECTS — BUDS AND FOLIAGE 123 In orchards where arsenical spraying is practiced, as for the codhn-moth, the young caterpillars are killed before doing much injury. On small trees they may be jarred off on to sheets or curculio-catchers and destroyed. When molting, and during the heat of the day, the caterpillars collect in large masses on the trunk and branches, where they may be readily brushed down and crushed. After defoliating a piece of wood- land the caterpillars frequently migrate to near-by orchards in countless numbers. Banding the trunks with tree tangle foot or loose cotton bands will prevent the ascent of these wandering larviB. The egg-rings are easily seen while pruning, especially on small trees. They should be removed and burned, for if thro^vn on the ground the young larvae may be able to crawl to the tree and so survive. References N. Y. (Geneva) Agr. Exp. Sta. Bull. 159. 1899. The Yellow-necked Apple Caterpillar Datana ministra Drury In the Northern states and Canaila apple branches are often defoliated in late summer ])y colonies of l)la('k and yellow striped caterpillars about two inches in length when mature ; the head is black and the next segment is yellow, whence the common name. While a few colonies are found evc^ry year they are only occasionally abundant enough to do serious damage. Besides the apple, ^^^ ,^^ _ ^^^^^ ^^ .^e yellow-necked this caterpillar also attacks apple caterpillar. Nat. size. pear, cherry and quince, as well as many forest trees. 124 FRUIT INSECTS Fig. 135. Yellow-necked apple caterpillars in rest- ing position. The moths ap- pear in June and July in New York ; they have an ex- panse of from If to 2 inches ; the front wings are cinna- mon-brown, crossed by three or four dis- tinct darker Unes ; the hind wings are pale straw-color, and the front of the thorax is a rich reddish-brown (Fig. 134). The female deposits her white, ovoid eggs in a flat cluster of from 25 to 100 on the underside of the leaves. The young caterpillars are chestnut-brown in color with obscure darker stripes. At first they feed en- tirely on the under- side of the leaves, but after the second molt they begin eat- ing the edge of the leaves. The seg- ment behind the head now becomes orange or yellow and the body is dis- tinctly striped with black and yellow Fig. 136. Cluster of yellow-necked apple cater- pillars. APPLE INSECTS— BUDS AND FOLIAGE 125 and sparsely clothed with rather long whitish hairs. The caterpillars always feed in colonies and soon strip a branch of its leaves. When disturbed they have the curious habit of bending back the front part of the body with a jerky motion and at the same time elevat- ing the hind end of the body as shown in Figure 135. They become full-grown in August and September, and enter the ground for a few inches and there transform to brownish pupae (Fig. 137) a little less than an inch in length, without forming coccons. There is only one l)rood annually. Co7itrol. The work of these caterpillars is so conspicuous that it is easy to locate them. On small trees it is perfectly practicable to shake them off and crush them on the ground. On larger trees the young caterpillars can be killed by spraying with arse- nate of lead, 4 or 5 pounds in 100 gallons of water. Fig. 137.— Pupa of the yellow - necked apple cater- pillar. En- larged. References Beutenmiiller, Can. Ent. XX, pp. 16-17. 1888. N. H. Agr. Exp. Sta. Bull. 139, pp. 213-215. 1908. The Red-humped Apple Caterpillar Schizura concinna Smith and Abbot Feeding in colonies at the ends of the branches like the pre- ceding species the red-humped apple caterpillar often attracts attention in August and September. It is rarely a serious pest on older trees but the caterpillars sometimes defoliate young trees in August and thus prevent the ]:)roper ripening of the wood. It attacks apple, cherry, plum, apricot, pear, black- berry and a number of forest trees. In the Northern states the inconspicuous grayish-brown 126 FRUIT INSECTS moths fly in June and July. The female has an expanse of about If inches ; the male is a little smaller and more distinctly marked. The female deposits her white, nearly round, slightly Fig. 138. — Moth of the red- humped apple caterpillar. Nat. size. Fig. 139. — Egg-mass of the red-humped apple caterpillar. Enlarged. flattened eggs in clusters of 40 to 100 on the underside of the leaves (Fig. 139). The young caterpillars feed at first on the underside of the leaves only, but as they grow larger eat the edges of the leaves. They feed in col- ^^^^^^M| ^ onies and are soon able to strip a branch of its leaves. When full-grown the caterpillars are an inch or more in length ; the head is coral red, the body is striped with black and yellow or whitish lines and on the fourth segment there is a prominent reddish hump (Fig. 140). The body is ornamented with rows of blunt black tubercles, largest on the Fig. 140. — Red-humped apple caterpillars feeding. APPLE INSECTS — JiUDS AND FOLIAGE 127 hump. When at rest the tip of the body is held in an elevated position. In the North, there is only one brood, the caterpillars ma- turing in August and September. They construct slight cocoons under trash on the ground and as a rule remain in the larval condition through the winter, pupating the following May or June. In the South where there are two broods, the first brood of caterpillars may form their cocoons in curled leaves. The red-humped apple caterpillar may be controlled by the measures recommended for the yellow-necked apple caterpillar (page 125). References Mass. (Hatch) Agr. Exp. Sta. Bull. 28, pp. 17-19. 1895. Packard, Nat. Ac. Sci., VII, pp. 212-217. 1895. The Saddled Prominent Heterocampa guttivitta Walker While generally distributed throughout the northern and eastern United States this beautiful green saddle-marked caterpillar had never attracted attention by its injuries until the outbreak of 1907-1908 in New York, Vermont, New Hamp- shire and Maine, where large areas of forests were defoliated. It is primarily a forest insect feeding on the beech, birch, maple and oak, but is also destructive to the apple. In Maine the parent moths emerge the latter part of May and during June. The moth has an expanse of about two inches ; it is brownish-gray in color and the front wings are crossed by indistinct darker lines. The female deposits her smooth, pale green, slightly flattened eggs singly on the leaves. They hatch in about nine days. The young caterpillars in the first stage bear nine pairs of black horns along the back ; the first pair back of the head are much longer than the others 128 FRUir INSECTS and branched like antlers, whence the name antlered maple caterpillar, sometimes given to this species. At first they merely skeletonize the leaves, but after the first molt, feed at the edge of the leaf, eating out portions between the larger veins. The full-grown caterpillar is about IJ inches in length, and varies greatly in coloration. They are usually pale green and have a conspicuous saddle-shaped mark on the third to the fourth abdominal segments. The tip of the abdomen tapers to a point and is usually held in an elevated position. The caterpillars do not cling tightly to the branches and may be readily shaken to the ground. They become full-grown in about five weeks, having molted four times ; they then descend to the ground, where, just below the surface or under the leaf mold, they construct a slight cocoon of silk, within which they change to pupae, remaining in this condition until the following spring. There is but one brood annually in Maine. Control. In the orchard the saddled prominent may be easily destroyed by spraying the trees with arsenate of lead, 4 pounds in 100 gallons of water, soon after the eggs hatch. In case the or- chard adjoins woodland or other untreated trees, it may be found advisable to band the trunks with some sticky material like " tree tanglefoot " to prevent the ascent of wandering caterpillars. References Maine Agr. Exp. Sta. Bull. 161. 1908. N. H. Agr. Exp. Sta. 19th & 20th Repts., pp. 514-531. 1908. The Gipsy Moth Porthetria dispar Linnaeus The gipsy moth is a native of Europe, Asia and northern Africa, where it has long been recognized as a serious enemy of orchard and forest trees. There its outbreaks are periodic APPLE INSECTS — BUDS AND FOLIAGE 129 and often very severe, vast areas of forests are sometimes devastated and many park and orchard trees either killed or seriously injured. It was introduced into Massachusetts in 1869 at Medford near Boston by a French naturalist who was conducting experi- ments with silk- worms. Some of the insects accidentally escaped and became established in the immediate vicinity but did not attract particular attention for about twenty years. In 1889, however, the cater- pillars appeared in enormous numbers, defoliated many forest, shade and orchard trees, and excited great alarm among the residents of the region. At first the state at- tempted to exter- minate the pest, ex- pending large sums of money for that purpose, but in 1900 abandoned tlie i)roj- ect and left the gipsy moth to breed and spread unmo- lested until 1905, when the enormous losses inflicted and the continued increase in the size of the infested area com- pelled the resumption of repressive work. In spite of the expenditure of immense sums of money by both the state w.'' r«*cy>-^:^^^ -M p'Tc Fm. 141. Gipsy moth egg-masses in a cavity ii) tree trunk. M FRUIT INSECTS and federal governments, the gipsy moth has gradually ex- tended its range over eastern Massachusetts, Rhode Island, the southeastern part of New Hampshire and has invaded southern Maine. Isolated colonies have also been found in Connecticut, western Massachusetts and New York. It has a wide range of food-plants, including most forest and fruit trees, with the exception of ash, juniper and red cedar, and the maples are rarely attacked when other food is available. The caterpillars seem to prefer oak, willow and apple, but will eat almost any kind of foliage whe,n driven to it. The winter is spent in the egg state. The egg- masses are roughly oval in outline, al)out an inch in length, light brown in color and covered with hairs from the moth's body. They are attached to the trunk or branches of trees, or are placed in cavities in the tree (Fig. 141), in piles of cord wood, lumber piles, stone walls and stone piles, or in any conveniently sheltered place. Each mass contains normally 400 to 500 eggs, but in cases where the larvae have been starved they are small and sometimes contain only 50 to 75 eggs. The eggs hatch in the spring just as the buds are bursting and the young, reddish- FlG. 142. — Full and partly grown gipsy moth caterpillars. APPLE INSECTS — BUDS AND FOLIAGE 131 brown caterpillars feed on the tender leaves, which they riddle with small holes. As they grow larger they devour the whole leaf with the exception of the larger veins. Until about half grown they are able to suspend themselves by a thread of silk and are thus likely to fall on passing vehicles and be transported considerable distances. The larger caterpillars avoid the sun ^^^^^^^^^l^v^ y ^Sl ^H ^^8 Wf^'^^W^ 1 ^^^m ^MHI^^hB^H HH^n fM^I^H^^HJ^^H ^Yf'miassBBiksm..J^^?W H PHP^H l^Hi m-'^^mmf^makJ/KKlm Fig. 143. — Gipsy iiiotli itiug egg-mass, aiul pupa^ in their cocoons. as much as possible, feeding at night or in cloudy weather. They become full-grown in about seven weeks or about the first week in July. The full-grown caterpillar (Fig. 142) averages about two inches in length ; the ground color is dark gray and there are eleven pairs of prominent tubercles on the back, the first five pairs are blue, the last six dark red. When full-grown or sooner, if the food supply gives out, the cater- pillars crawl to some sheltered spot, where they spin a frail 132 FBTTJT INSECTS IG. 144 cocoon consisting of a few threads of silk, and there transform to daik r e tl d i s li - 1) r o w n pupa^ (Fig. 143), bearing groups of yellowish hairs. The pupal stage lasts from a wcvk to 17 days. As a rule, the male moths emerge Male uiui female gipsy moths. ^ j.^^|^, ^^^y^^^ ^j^^^^ the females. The male has a light brown body and the wings are yellowish -brown; the front wing is traversed by four wavy dark brown lines. In the female the body is light buff and the wings are grayish white ; the dark brown markings on the front wings are similar to those of the male (Fig. 144). The male moth has an expanse of one and a half to two inches, and the females average somewhat larger. The male flies with a characteristic zigzag mo- tion but the female is un- able to use her wings and * ^^^- ^^^- "~ Calosoma sycophanta, a Euro- n J -i 1 pean ground-beetle introduced into New Eng- USUally deposits her eggs land to control the gipsy moth. Enlarged. APPLE INSECTS — BUDS AND FOLIAGE 133 within a few inches of the pupal case from which she emerged (Fig. 143). In its native home the gipsy moth is held in check by its natural insect enemies, both parasitic and predaceous. For several years now the United States Bureau of Entomology has been importing and liberating thousands of these beneficial forms with the hope that ultimately they may be able to hold ('*'* '.^m^^bi^i^FfNiii^'^i^iJH^H !«! &. - 'm fc^^HHyjplf '^ r^*''?^*Bp ^^1 ^V^*^^^ -H ifl^'^ ;i M 'S2¥ P-'^ m . ■i f jlf^r^^-''' m 1 .,. ;. .^t HHfeg;;.::; 1 1 % 1 wmm *"m i Fig. 146. Combing sticky hands and brushing down caterpillars of the gipsy and brown-tail moths. the species in check. Some of these introduced insects have already become established in the infested territory and are multiplying rapidly. One of the most promising of these is a large green ground beetle (Calosotna sycophanta L.) shown in Figure 145. In both the adult and larval state it preys on the larvae and pupae of the gipsy moth. Means of control. The control of the gipsy moth in orchards is not a difficult matter. During the winter the trees should be carefully 134 FRUIT INSECTS examined for egg-masses and the eggs killed by saturating them with crude coal-tar creosote to which a little lampblack has been added as a marker. The work of destroying the eggs can be greatly facilitated by having the trees properly pruned, by removing all flakes of rough bark and by filling all cavities with cement or covering them with tin. The trees should be sprayed, soon after the eggs have hatched, with arsenate of lead, 10 pounds in 100 gallons of water. If the caterpillars are half- ^ ^» pB- \^^ ^^M m ♦ ^m ^IBH KM B'te'-^aiM r ' ' jljpl j| ^^fl g| Fig. 147. — Orchard defoliated by gipsy moth caterpillars, in July. grown, it is advisable to use 13 or 15 pounds. It is very difficult to poison nearly full-grown caterpillars, and for the best results the spraying should be done while the caterpillars are small. If the orchard is located near untreated woods or other orchards the trees should be banded with tanglefoot to prevent the ascent of caterpillars migrating from the untreated area when the food supply runs short (Fig. 146). References Forbush and Fernald, The Gipsy Moth, Boston, 1896. U. S. Dept. Agr. Farmers' Bull. 275. 1907. APPLE INSECTS — BUDS AND FOLIAGE 135 U. S. Bur. Ent. Bull. 87. 1910. (Contains references to the important reports on the gipsy and brown-tail moths published by the various New England States.) U. S. Farmers' Bull. 564. 1914. The Brown-tail Moth Euproctis chrysorrhoea Linnaeus This well-known and destructive European caterpillar was accidentally introduced into Massachusetts in the vicinity of Boston probably in the early nineties, but did not attract attention by its ravages till 1897. Since that time it has gradually extended its rav- ages so that now the infested area includes part of Rhode Island, the greater part of Massachusetts, southern New Hampshire, southern Maine and extends into New Brunswick and Nova Scotia. The brown-tail moth has been able to spread more rapidly than the gipsy moth, owing to the fact that the females are good fliers, and when aided by favorable winds may be transported to a considerable distance. Unlike the gipsy moth, the brown-tail caterpillars do not feed on coniferous trees, their favorite food-plants being apple, pear and oak. The caterpillars, and to a less extent the moths, are provided with minute barbed hairs, which are poisonous to the human skin, causing an annoying and sometimes serious irritation known as th(^ brown-tail rash. Fig. 148. — Brown-tail moth depositing egg-mass on a leaf. 136 FRUIT INSECTS The brown-tail moth has an expanse of about one and one half inches ; the wings are white and the tip of the abdomen bears a tuft of yellowish-brown hairs, hence the name of the insect. The males are a little smaller than the females, and the brownish tuft is not so conspicuous. The moths appear the first week in July, and in badly infested areas are often attracted to electric lights in countless numbers. After mating the female moth deposits from 200 to 300 globular yellowish Fig. 149. — Brown-tail moth caterpillars, one in process of molting. eggs in an elongate mass on the underside of a leaf (Fig. 148). This egg-mass is about f of an inch in length and is thickly covered with brownish hairs from the abdomen of the female. The eggs are deposited during the first three weeks in July and hatch in 15 to 20 days. The young caterpillars feed in colonies on the t(nider, terminal leaves, webbing them together with silk to form a snug nest (Fig. 150) two or three inches in length within which they pass the winter in a partially grown condi- tion, having molted two or three times before going into hiberna- tion. These winter nests, usually situated at the tips of the branclu^s, are conspicuous objects while the trees are bare of APPLE INSECTS — BUDS AND FOLIAGE 137 foliage. In early spring, just as the buds are bursting, the caterpillars leave their winter quarters and resume feeding on the unfolding leaves, and if abundant may keep the trees stripped of foliage. They molt four or five times in the spring and become mature toward the last of .Jun(\ The full-grown caterpillar (Fig. 149) is about Ih inches in hmgth, nearly black in ground color, clothed with tufts of brownish barbed hairs and has a row of nearly white tufts on each side of the body; there is a coral-red tubercle on the dorsum of the nth and 12th segments. When mature the cater- pillars spin loosely woven cocoons in , , - Fig. 150. — Winter nest of the iHown-tail moth. curled leaves, crevices in bark of trees, or under any convenient shelter ; they are usually found in masses. The pupse are about f inch in length and dark brown in color. The pupal period averages about 20 days. Control. As an orchard pest, the brown-tail moth can be most readily controlled by collecting and burning the conspicuous hibernating nests during the winter months. The newly-hatched caterpillars can be killed the first or second week in August by a thorough application of arsenate of lead, 8 pounds in 100 gallons of water. Attempts to poison the over-wintering caterpillars, when they appear on the buds in the spring, are not so success- 138 FRUIT INSECTS ful. The caterpillars often devour the leaves as fast as they appear and it is difficult to keep the surface of the rapidly ex- panding leaves covered with the poison ; furthermore, the caterpillars are larger then and consequently harder to kill. If for any reason the destruction of the winter nests has been neglected, and spring spraying must be employed, some good can be accomplished by using arsenate of lead, 10 to 14 pounds in 100 gallons of water. References Fernald & Kirkland, The Brown-tail Moth. 1903. U. S. Farmers' Bull. 264. 1906. U. S. Bur. Ent. Bull. 87. 1910. U. S Farmers' Bull. 564. 1914. Climbing Cutworms The sleek, plump, dull-colored, obscurely marked caterpillars (Fig. 151), ranging from one to nearly two inches in length and commonly known as cutworms, attack nearly all kinds of field and garden crops, and some of them often climb fruit trees, bushes and grapevines at night to eat the opening buds. More than a dozen different kinds of these climb- FlG. 151. — One of the climbing cutworms, Poru- -^^^ CUtwormS liaVC sagrotis vetusta (X 1^). * . been caught at their destructive work and identified as follows : The yellow-headed cutworm (Hadena arctica Boisduval). The white-spotted cutworm {Homohadena badistriga Grote). APPLE INSECTS — BUDS AND FOLIAGE 139 The variegated cutworm (Peridroma margarilosa saucia Hiibner). The dark-sided cutworm (Paragrotis messoria Harris). The white cutworm (Paragrotis scandens Riley). The well-marked cutworm (Noctua clandestina Harris). The black-lined cutworm (Noctua fennica Tauscher). The mottled-gray cutworm (Rhynchagrotis alternata Grote). The red cutworm (Rhynchagrotis placida Grote). The speckled cutworm (Mamestra subjuncta Grote and Robinson). The dingy cutworm (Schizura ipomcece Doubleday). The spotted-legged cutworm (Porosagrotis vetusta Walker). A species of Prodenia and Noctua baja Fabricius. Cutworms develop from eggs laid by night-flying Noctuid moths that are frequently attracted to lights in large numbers. Light, loose soils are most often infested by these caterpillars, and where there is a scarcity of low-growing vegetation they will climb almost any plant, even to the tops of high trees. As peaches are often grown in such light, sandy soils, both young and old trees have suffered severely from cutworms in various parts of the United States. The buds and leaves of grapevines are also favorite delicacies for them. Young apple, pear and cherry trees, or blackberry, raspberry and currant bushes, or young shade trees and shrubs grown in such soils are also often attacked. The half or two-thirds grown cutworms, hungry after a long winter's fast in the ground, emerge early in the spring as soon as the buds begin to open. Like thieves in the night, they crawl up the trees, vines or bushes and from about 8 p.m. until nearly morning continue their destructive work of eating the buds. In some instances the culprits have been first discovered on still nights by hearing the noise made by the clicking of the hundreds of tiny, hungry jaws as they devoured the buds. Fifty cutworms have been found at one time on a tree set the previous year ; from 500 to 800 have been counted going up the trunk of a 12-year old apple tree in a single night ; and 1500 have been taken from such trees during the 2 or 3 weeks they work in spring. Young m 140 FRUIT INSECTS trees and grapevines are often stripped of buds and killed in a single night, and the cutworms sometimes gnaw off the tender bark of the twigs, or may even girdle the trunk if pre- vented from ascend- ing by some barrier. Towards morning they drop to the ground, burrow in an inch or more, and remain during the Fig. 152. — Moth oi Porofiagrotis oetusta (x IV- ^ tt ^^ • n day. Usually m 2 or 3 weeks, or by the time the trees are in leaf and blossom, the cutworms become full-grown, cease feeding and soon trans- form to the parent moths (Fig. 152). Remedial measures. Orchards or vineyards on the heavier soils are rarely troubled by climbing cutworms. On the light, sandy soils usually pre- ferred by these pests, keep the ground entirely . free from all grass and weeds for 2 or 3 months after July 15, so as to starve out the recently hatched caterpillars. If some cover crop, like rye, oats, clover,* rape or cow-peas, could be sown late in fall between the rows of trees, vines or bushes, and plowed under after these. fruits were in leaf, it would furnish the cutworms something besides fruit-buds to eat and thus prevent much of their destructive work. A collar of cotton batting or wool properly put on the trunks of trees or grapevines makes almost a perfect and a very cheap barrier to the ascent of the cutworms. Unroll the batting into thin sheets and cut into strips 4 or 5 inches wide. Wrap these around the trunks, letting the ends overlap an inch or more, then tie with common white twine at the bottom and carefully roll the top of the band down over the bottom edge, thus form- APPLE INSECTS— BUDS AND FOLIAGE 141 ing an inverted cotton batting funnel around the trunk. These barriers are not easily matted down by rains and a few hours of sunshine makes them as fluffy and effectives as ever. In very rainy seasons use wool, which can be put away and used for several seasons. Entice them away or prevent their getting to the buds by the above methods, then proceed to kill the culprits. Go out with a lantern at night, pick off the few that are able to reach the buds and collect or crush those trying to get up the trunks. As most of them can be found during the day just beneath the surface of the soil within a radius of a foot or two around the base of the trees or vines, it is an easy matter to dig them out. The fat, sleek caterpillars will make dainty morsels for a flock of chickens or other fowls. Many of these climbing cutworms can also be poisoned with a mixture of bran (25 pounds) and Paris green or white arsenic (2 pounds) and water enough to make a soft mash. Cheap sugar or molasses may be added to prevent it drying out so quickly, but apparently does not add to its attractiveness. First put on the cotton batting barriers, then drop a few large spoonfuls of this poisoned mash around the base of the trees or vines at nightfall. Many of the hungry cutworms will eat this deadly mash, either before they try to go up the trees or vines, or discouraged by the barrier, return and feast on it. Sometimes 90 per cent of them can be poisoned in this way. Of course, all poultry and other domestic animals must be kept away from the places where this poison bait is being used. Reference Cornell Agr. Exp. Sta. Bull. 104. 1895. CHAPTER IV APPLE INSECTS — APHIS, SCALES, AND OTHERS Plant-lice or Aphids Three different kinds of these small, soft-bodied sucking insects may attack the opening buds, the foliage and sometimes the young fruits on apple trees : --^ (Fig. 153). Often two species of these aphids work on the same tree in the spring. Nurs- ery stock is frequently seri- X'-' '••^^^. Fig. 153. •Aphid eggs on apple twig. Fig. 154. — Apple leaf aphis on quince. 142 APPLE INSECTS 143 ously injured, the leaves being badly curled and the growth of the tree checked. The aphids secrete a sweet liquid known as honey-dew in which a black fungus de- velops and gives the infested foliage and twigs a sooty appearance. In large, bear- ing apple orchards, these plant-lice some- times appear in incredible numbers and not only curl and kill some of the ter- minal leaves but attack the young fruits, preventing their full development and giving them a knotty, stunted appear- ance (Figs. 157, 158 and 159). The three species of these aphids now common on apple trees throughout the United States are Aphis pomi, Aphis sorbi and Sipho- coryne avence. The interesting and somewhat compli- cated life histories of these plant-lice have not been fully worked out. The last two species breed on the apple trees for only a few generations in the spring and early summer, then migrate to other food-plants, but return to the trees in the fall, where the hibernating eggs are laid. The first species remains on the trees throughout the year. The wonderful rapidity with which these aphids multiply parthenogenetically enables even those that work on the trees only a part of the season to develop in sufficient num- bers to do serious injury to the foliage or fruit before they mi- grate to their summer food-plants. Natural enemies of the apple aphids. Cold, heavy rains, both in early spring and late autumn, re- move and doubtless kill many of the aphids, thus often prevent- ing serious infestation in orchards. Fungous diseases also destroy large numbers under favoraWe weather conditions. Several species of ladybird beetles, aphis-lions and maggots of Fig. 155. — Newly hatched aphids clustering on an opening apple bud. 144 FRUIT INSECTS Syrphus flies often reap a rich harvest of apple plant-lice. These predaceous enemies, aided by several minute parasitic flies, are very effective aids in reducing these prolific little pests to much less injurious numbers. If it were not for these adverse weather conditions, fungous troubles, and insect enemies, apple Fig. 156. — Dippin