Maine Avvealtara Experiment Station ORONO CHAS. D. WOODS, Director APPLE TREE INSECTS OF MAINE [383-6-10] University of Maine MAINE AGRICULTURAL EXPERIMENT STATION ORONO, MAINE. CHAS. D. WOODS, Director APPLE, TREE INSECTS OF MAINE. Epira M. Patcu, O. A. JOHANNSEN. Before it is possible to combat an insect pest intelligently we must learn something of its habits and of its vulnerable points. When these are known proper remedial measures may then be taken for its extermination or repression. To meet the needs of those who wish to learn something of the commoner injuri- ous insects which affect the apple tree and its fruit this circular has been prepared. It is a compilation largely from the Ento- mological bulletins and circulars of the Maine Agricultural Ex- periment Station. We desire to acknowledge the use also of publications of the United States Department of Agriculture and of other sources. There are very many different species of insects ranging in size from less than 1-50 of ananch to about 8 inches in length. From the United States alone over 30,000 species have been recorded of which over 400 are known to affect in greater or less degree the apple tree or its fruit. Though there are many that are, it must not be supposed that all insects are injurious for by far the larger number are either harmless or actually beneficial. Ruthless destruction of insects by means of trap lanterns and the like is to be deprecated since these methods 2 are as apt to capture the beneficial and the harmless as the injurious. Poisons, traps, and other repressive measures must be used with caution, and at the right time and place in order to be most effective. Though technical terms will be avoided in this circular when possible, it may not be out of place here to explain the few which it will be necessary to use in the descriptive matter which is to follow. Though differing in many particulars all insects possess a segmented body which in the adult stage is arranged in three regions, head, thorax or midbody, and abdomen or hind body. The thorax in the adult is provided with 3 pairs of legs and may be either winged or wingless. Some insects (e. g., grasshoppers) after emerging from the ege gradually increase in size until they reach maturity but without undergoing any abrupt change in external appearance except in the acquisition of wings. Others, however, pass through 4 distinct stages, viz., egg, larva (caterpillar, or grub or maggot), chrysalis or pupa (often enclosed in a cocoon) and the imago or mature insect. After the insect has acquired wings it is mature and no longer increases in size. ‘Thus a small beetle is not the young of a larger one, nor is a small fly the early stage of one of greater magnitude. Insects are divided into a number of natural groups or orders by which they are known in technical literature and not infre- quently in popular accounts also. ‘The Orthoptera are four winged; the first pair are thickened and partly overlap when at rest; the second pair are thinner and are folded in plaits like a fan. ‘The mouth parts are formed for biting. To this order belong the cockroaches, crickets and grasshoppers. The Neu- ropteroids include the dragon flies (popularly known as darn- ing needles), May flies, stone flies and the like. The only in- sects which are rightly called “bugs” are the Hemiptera, crea- tures of various shapes, having jointed beaks adapted for pierc- ing and sucking. Plant lice (figs. 31, 32), scale insects (figs. 3, 4), bed bugs, plant bugs (fig. 28), etc., belong to this order. The butterflies and moths, scaly winged insects, are classed as Lepidoptera. ‘These are harmless to vegetation in the adult stage, but many species in the larval (caterpillar) stage, then provided with biting mouth parts, are among our most destruc- 6) tive pests. The codling (fig. 40), gypsy, brown-tail and other moths are well known examples. The Diptera to which the mosquito, apple maggot (fig. 24), and house or typhoid fly be- long, are two-winged when mature. The larva of the mosquito, so common in a rain water barrel, is known as a wriggler, while the corresponding form of the fly is known as a maggot. The plum curculio (figs. 25-27), the apple tree borer (figs. 1, 2), the blundering June beetle, and the potato beetle are members of the Coleoptera, insects having hard, shell-like fore wings which meet in a longitudinal line along the middle of the back. Both the larve (known as grubs) and the adults have biting mouth parts and in some species are equally concerned in the destruction of plants. Some lady beetles on the other hand are beneficial because they feed on small injurious insects such as scales and aphids. Ants, bees, wasps, a host of species of minute 4-winged parasitic flies, as well as some injurious saw- flies are members of the order Hymenoptera, the adults of which are four winged. The larve, most of which are known as grubs or maggots, usually have well developed heads with biting mouth parts and frequently provided with legs. While the foregoing classification is adopted in most text books, it is more convenient in dealing with the species of the apple to arrange them in accordance with the character of the injury they cause and to this end we will first divide them into 3 primary groups. A. Injuring root, trunk or branch; borers and sap feeders. Page 3. = AA. Injuring the foliage; biting or sucking insects. Page 13. AAA. Injuring the fruit; maggots, caterpillars, bugs and beetles. Page 46. A. INJURING ROOT, TRUNK, OR BRANCH. a. Borers in the wood. 1. A large white grub about 1 inch long when grown, w‘th brown head; thorax not much thicker than the abdomen. Bores mainly at the base of the trunk. Its presence is indicated by the wood dust it throws out of its burrow. (hig; 1) Round-headed borers. Page 4. 2. A whitish grub about % inch long when grown, with flat- tened thorax about twice as wide as the abdomen. Works on the trunk and large branches. (fig. 2). Flat-headed borers. Page 7 4 3. A very small larva which lives in small rounded “shot holes” about 1-16 inch in diameter. Adults are small brown beetles. Shot-borer bectle. Page 8. b. Scale insects and plant lice. 1. Scale about 1-10 inch long on twigs; shaped like oyster shell. (fig. 3). Oyster-sheli scale. Page 9. 2. A small rounded scale. (fig. 4). San Jose scale. Page to. 3. Plant lice with white downy secretion; cause wart-like swell- ings on roots, and also are found on the twigs. (figs 34,. 35): ; iVoolly aphis. Page 12. a. BORERS IN THE WOOD. t. Rounp-HkEApEpD AppLE-TREE BORER. (Saperda candida Fab.) Fig. 1; a, larva; b, pupa; c, adult. (After Riley). The first intimation that the grower may have of the presence of this borer in his trees, unless he be forewarned, is in their retarded growth and the sawdust-like castings, consisting of excrementitious matter and gnawings of woody fiber, which the larve extrude from the openings into their burrows. This man- iiestation is usually accompanied by more or less evident dis- coloration of the bark and, in early spring particularly, by slight exudation of sap. The parent of this borer is a beautiful beetle, measuring from three-fourths to nearly an inch in length, the male being per- ceptibly narrower than the female. The legs are gray, the under surface of the body and the head are silvery white, and the upper surface is light yellowish brown with two longitudinal white stripes extending through the thorax and elytra or wing- covers to the tip, as is shown in the accompanying figure 1, c. 5 The larva, when mature, measures from three-fourths to a little over an inch in length. It is legless, fleshy, and somewhat grub-like in appearance, cylindrical in form, and light yellow in color. The head is darker. The pupa, illustrated at b, is nearly as long as the adult insect, which it resembles in a superficial manner, the head being bent down toward the breast, and the legs and long antennz folded upon the ventral surface. Its color is similar to that of the larva. ; The beetles make their first appearance of the season late in May or in June, according to locality. During the night they come forth from the trunks of the trees in which they have bred, and at this time may be seen in flight. Soon after their first appearance the sexes mate and eggs are deposited. The female first makes an incision in the bark— probably by means of her mandibles—causing it to split slightly ; then, turning head upward, she places an egg under the bark nearly a quarter of an inch from the incision, accompanying the deposition by the extrusion of “a gummy fluid which covers and secures it to its place and usually fills up the aperture. In young trees with tender bark the egg is usually thoroughly hid- den, while in older trees it is sometimes so shallowly imbedded as to be readily seen.” The larve, soon after hatching, tunnel under the bark and feed on the sap-wood, gradually working their way upward and afterwards downward, usually remaining within a short dis- tance of, or below the surface of, the ground, particularly in young trees. By the end of the second year the larve have increased considerably in size and have now penetrated deeper into the solid heart-wood, their burrows being closely packed behind them with castings. The third year the larve gnaw outward to the bark, form a pupal cell composed partly of their castings and, with their heads pointing toward the bark, trans- form to pupe. With the approach of May and June they cut their way out by means of their powerful manibles and issue through a round hole as mature beetles. METHODS OF CONTROL, After borers have once entered a tree there is no better remedy known than to cut them out with a knife or other sharp instrument. Cutting the borers out, unless practiced with the 6 greatest care, is apt to result in injury, and it is far better to prevent the parent insects from depositing their eggs upon the tree. ‘This is not difficult of accomplishment, as oviposition is practically confined to two months in any single locality, usually June and July. The best preventives are impenetrable sub- stances placed about the trunk and various washes of a repellent nature. For this a few thicknesses of newspaper wrapped rather loosely about the trunk and extending about two feet from the base are all that is necessary. This covering should be tied, by preference with cord, which will readily yield or break with the natural expansion of the tree in its growth, and also be tightly fastened at top and bottom and hilled up with earth so that the beetles cannot obtain access to the tree from below. From the top of this covering upward it is best to use some deterrent alka- line or carbolated wash. Any one of several washes in general use against boring in- sects may be used as a deterrent. A good alkaline wash is pre- pared of soft soap reduced to the consistency of thick paint by the addition of caustic potash or washing soda in solution. A good fish-oil, or whale-oil soap, or common soft soap, is often used, and in some cases any one ot these is sufficient to deter the insects from depositing their eggs. The alkaline wash may be carbolated, if desired, by the addition of crude carbolic acid, at the rate of I pint to every Io gallons of the wash. Such a wash not only affords protection against this and other borers, but against scale and fungous diseases at these points, and is, moreover, of positive benefit to the tree. Caustic potash fish- oil soaps are among the best for insecticides. 2. Friat-HrapEep AppLE-TREE Borer. (Chrysobothris femorata Fab.) Big. 2; a, larva; b, pupa; c, adult. (After Riley). The adult insect (represented at c, fig. 2), measures from a little less to a little more than a half inch in length. It is flat- tened above, the upper surface of the body is dark metallic brown, and fresh specimens are coated here and there with a powdery gray substance, which is easily rubbed off. The wing- covers are ornamented as shown in the illustration, and under- neath, as may be seen when the insect is in flight, the body is a bright metallic greenish blue. The under surface is coppery bronze. The larva differs greatly from that of the round-headed borer. Its name, flat-headed borer, is derived from the peculiar flat expansion of the second thoracic segment—which is close to the head. In color it is light yellow and in length measures nearly twice that of the mature insect. It habitually rests in a curved position (fig. 2,a). The pupa (b) shows the form of the future beetle and is of the same yellow color as the larva. This borer attacks diseased or dying trees by preference, in- habits all parts of a tree from the base of the trunk to the limbs, and is not restricted to fruit trees. In all these respects it differs from the round-headed borer, but agrees with the latter in that it is injurious chiefly to young trees, its injuries being practi- cally confined to newly transplanted nursery stock and to trees which have been weakened through any cause, such as careless pruning, or insufficient nourishment due to poor soil or drought. Infestation may be detected by the discoloration of the bark- REMEDIES. The remedies advised for the round-headed borer are also of value and are generally employed against the present species. It is necessary, however, that deterrent coverings and washes 8 should be applied farther up the trunk and to as many branches as can be conveniently reached. Careful cultural methods.—Careful, clean methods of orchard management are essential as a measure of protection, and in- volve the cutting out of dead, dying, and injured deciduous forest and shade as well as orchard trees known to be chosen as food by this species. Care should be exercised in transplant- ing, and especially in pruning; and fertilizers should be used in order that the trees may be thrifty and better able to with- stand attack. Proper regard for these measures should give practical exemption from injury. 3. SHOT-BORER. (Xyleborus dispar.) The female beetles bore into the wood, making deep chanels which in small twigs interfere with the circulation of the sap, and the twigs wither, giving the appearance of blight. The exit holes through the bark are .06 of an inch in diameter and nearly circular, looking like small shot holes. The wood is green, showing that the insect attacks the growing tree. Liv- ing wood does not appear to be essential to the life and comfort of this species, for after a period of several weeks we found in a limb that had been in a dry place in a box, young larve, full grown pupz, and perfect beetles. When the larve are full grown they transform to pupz in the burrows, and finally emerge as small beetles about one-tenth of an inch long and of a dark brown or nearly black color, with the antenne and legs of a rusty red. The thorax is short, very convex, rounded and roughened. The wing covers are marked by longitudinal rows of punctures. The hind part of the body. slopes abruptly. The beetles leave their burrows in June and July and deposit eggs before August. REMEDIES. As the beetles work wholly under the bark they cannot be reached by insecticides. The only way is to watch the trees during the latter part of June and July and, if blighted twigs or diseased limbs are noticed, examine the branches for small pin holes; if found, the presence of this or some related species nay be suspected. The diseased limb should at once be cut 9 far enough below the injury to include all the burrows, and burned, to prevent the beetles emerging and attacking new trees. As these beetles live in forest trees, orchards near timber are more liable to become infested. be SCALE INSECTS AND PLANT-LICE. I. OVYSTER-SHELL SCALE. (Lepidosaphes ulmi.) This scale, which resembles an elongate oyster shell in shape (fig. 3, b) has long been known in this country, though believed to be a native of Europe. It is widely distributed and is ex- ceedingly abundant in Maine. Besides seriously injuring apple trees, the twigs of which often densely covered by them, they are found on the pear, plum, currant, dogwood, elm, maple and a number of other trees and shrubs. Fic. 3. Oyster-shell Scale. a, female scale from below, showing eggs; b, same from above greatly enlarged; d, male scale enlarged; c, female scales on twig, natural size, e, male scales natural size. (From year book, 1894 U. S. Dept. Agr.) In June the eggs hatch, the active young appearing as small white specks which soon attach themselves to new shoots by 10 their beaks. The scale then begins to form, gradually increas- ing in size. The scale of the female (fig. 3, a, b, c) is less than one-eighth of an inch long, narrow, usually curved when not crowded, (fig. 3, c) and nearly the same color as the bark upon which it is found. The scale of the male (fig. 3, d) is much smaller, less curved and usually not found on fruit trees. As with the San Jose scale the adult male is provided with both wings and legs while the female, remaining under the scale, has neither. REMEDIES. This insect is quite resistant to the application of sprays unless it be put on at the time when the young appear, before the formation of the scale. This is about the middle of June, though the exact date cannot be given as it varies with latitude and temperature. As soon as the young larve are observed the trees should be sprayed with soap solution (Formula 7), kero- sene emulsion (Formula 4), or whale-oil soap solution (For- mula 6), repeating if possible a week later. The kerosene emulsion should be put on in sunshiny weather and care should be exercised not to use an excess amount, lest the tree be injured. 2. SAN JOSE SCALE. (Aspidotus perniciosus.) The San Jose which is one of the worst insect pests of orchards in other states was discovered in the town of Lim- erick, Maine, in 1909. As there is always a danger of its introduction upon nursery stock from neighboring states, the observation of small circular scales about the diameter of a pin head (fig. 4) upon the twigs of fruit trees should imme- diately be reported. Fic. 4. a, Female, scale removed; b, cluster of scales; c, female scale; all greatly enlarged. (After Felt.) EL The female scale is circular in outline, grayish or blackish in color, and when examined under a lens will be seen to be somewhat raised above the bark especially in the center where there is a little prominence. When the scale is somewhat rubbed the center portion appears yellowish, around which the con- centric circles, representing lines of growth, may be seen (fig. 4,c). The full grown male scale is elongated, the prominence near one end and the lines of formation eccentric instead of concentric. If the scale be lifted by means of a needle, there will be seen a little yellowish body; the insect proper (fig. 4, a). The newly born insect of both sexes possess eyes, legs, antennz and mouth parts, and crawl about for a few hours upon twigs. When a suitable place is found they settle, insert their long beaks through the bark and begin to suck the plant juice. The scale begins to form even before the young insect becomes fixed, and is at first pale grayish yellow, gradually becoming darker, the central projection usually remaining lighter colored. The insect under the scale now loses legs and antennz, the female also losing her eyes. Later the male scale assumes an elongate oval shape, and later still, 3 or 4 weeks after birth, it again undergoes a transformation and appears as a mature insect with legs, antenne, eyes and wings. The female matures in 5 or 6 weeks, remaining fixed in position under the scale, leg- less and wingless. There are several generations each season. REMEDIES. While there are a number of insect parasites which are natural enemies of the scale, chief reliance must be placed upon fumi- gation and spraying early in the spring before growth begins to keep it under control. Miscible oils, kerosene emulsions (Formula 4), and lime and sulphur washes (Formula Io) are all to be recommended for sprays, while nursery stock imported from localities known to be infested should be fumigated. Com- plete directions for spraying and fumigating will be found in Farmers’ Bulletin 127, “Important Insecticides: Directions for their Preparation and Use,” and “San Jose Scale,” Circular 42, Second Series, Division of Entomology. ‘These papers may be obtained upon request by addressing “United States Depart- ment of Agriculture, Washington, D. C.” 12 3. Woo.ity APHIS OF THE APPLE. (Schizoneura lanigera Hausmann.) Throughout the summer on the lower portion of the trunk and particularly on the water sprouts of the apple may often be seen small bluish-white flocculent or cottony patches, which indicate the presence of colonies of one of the worst enemies of the apple, viz., the insect known as woolly aphis (fig. 34). It exists in two forms, the one just referred to, above ground on the trunk or water shoots, and another inhabiting the roots. On the roots its attacks induce enlargements or galls or swell- ings, and in the cracks of these galls and swellings the root form occurs in clustered masses. The injury to the trees is due both to the sucking up and exhaustion of the vital plant juices and to the poisoning of the parts attacked, as indicated by the consequent abnormal growths. The damage is particularly serious in the case of nursery stock and young trees and is less often important after the tree has once become well established and of some size. Where this insect is abundant all the roots of a young tree to the depth of a foot or so become clubbed and knotted by the growth of hard fibrous enlargements (fig. 35) with the results in a year or two of the dying of the rootlets and their ultimate decompo- sition with attendant disappearance of the galls and also of the lice, so that after this stage is reached the cause of the injury is often obscure. On the trunks the presence of the lice some- times results in the roughening of the bark or a granulated condition which is particularly noticeable about the collar and at the forks of branches or on the fresh growth around the scars caused by pruning, which latter is a favorite location. On the water shoots, they collect particularly in the axils of the leaves, often eventually causing them to fall, and on the tender greener side of the stems. The damage above ground, though commonly insignificant, is useful as an indication of the prob- able existence of the lice on the roots. A badly attacked tree assumes a sickly appearance and does not make satisfactory growth, and the leaves become dull and yellowish, and even if not killed outright it is so weakened that it becomes especially subject to the attacks of borers and other insect enemies. 13 ‘The common forms both on the roots and above ground are wingless lice, not exceeding one-tenth of an inch in length, and of a reddish-brown color, and abundantly covered, especially in the aerial form, with a flocculent waxy excretion. In October or November, among the wingless ones, numbers of winged individuals appear, which are also all females, and are the parents of a true sexed generation of minute, wingless lice, the females of which give birth to a single “winter egg.” This egg is attached within a crevice of the bark. The winged females appear somewhat abundantly in autumn, and are one of the means of the dispersal of the insect. They are very minute, clear-winged, gnat-like objects, greenish- brown, almost black in color, with the body covered with more or less of the cottony excretion. REMEDIES AND PREVENTIVES. | The foregoing account of the habits and characteristics of the woolly aphis will enable us to suggest certain measures to control it. The aerial form presents no especial difficulty, and can be very readily exterminated by the use of any of the washes recommended for plant-lice, such as kerosene emulsion, tobacco decoction, a strong soap wash (Formulas 4, 8, 6), etc., the only care necessary being to see that the wash is put on with sufficient force and thoroughness to penetrate the cover- ing and protecting cottony excretion. If the wash be applied warm, its penetration will be considerably increased. The much more important root form, however, is more diffi- cult to reach and exterminate. The common recommendations are of applications of strong soap or tobacco washes to the soil about the crown, or soot, ashes, or tobacco dust buried about the roots; also similarly employed are lime and gas-lime.” Badly infested nursery stock should be destroyed, since it would be worth little even with the aphides removed. AA. INJURING THE FOLIAGE. (Divisions a, b, c, and d). a. Plant lice, small greenish, blackish or reddish lice-like sucking imsects. 1. Greenish plant lice in colonies causing leaf curl. (fig. 33). Green apple-aphis. Page 16. 2. Reddish plant lice in colonies causing leaf curl. 4 Rosy aphis. Page 17. 14 Insects feeding freely upon the leaves without a nest and not con- cealed within leaf or bud. 1. A “measuring worm” or looping caterpillar, when grown about 1 inch long; olive green when young, becoming yel- lowish or brownish when grown; with brownish longitudi- nal stripes and white band on sides; under side pale or flesh colored. (figs. 5, 6). I. With 2 pairs of legs at rear of body. Spring canker Worm. Page 18. II. With 3 pairs of legs at rear of body. Fall canker worm. Page 19. Very large hairless green caterpillar, 4 inches long when grown; body with several red, yellow and blue bead-like tubercles. (fig. 7). Cecropia caterpillar. Page 21. 3. A large black and yellow longitudinally striped caterpillar with yellow neck; very sparsely covered with long soft hairs. (fig. 9). Yellow-necked caterpillar. Page 22. 4. A caterpillar with black, white and yellow longitudinal stripes; head and fourth body segment bright red, with a number of stiff, blunt black spines. (fig. Io). Red-humped Caterpillar. Page 23. 5. A smooth mottled caterpillar; grayish brown above, gray- green beneath with yellow head. (fig. 55). ; Mottled fruit caterpillar. Page 24. 6. Smooth greenish caterpillar 1% inches long when grown, with various colored blotches and marks on the back. (fig; 12) Saddled prominent. Page 25. 7. Very small smooth greenish yellow caterpillars (4% inch or less), feeding upon upper surface of leaf. (fig. 14). Apple-leaf Bucculatrix. Page 27. 8. Hairy caterpillar with four white humps of hair on the back, and black pencils of hair on head and tail. (fig. 15). J... Head ired. White-marked tussock. Page 28. Il. Head black. Antique tussock. Page 28. 9. Hairy caterpillar; ground color bluish with a single line of white dots on the back. (fig. 16). Forest tent caterpillar. Page 30. 10. Hairy caterpillar, ground color brownish, with broken white stripes on each side when full grown; the young are in winter nests, they are brownish with 2 reddish dots on back. Brown-tail. Page 32. 11. Hairy caterpillar, ground color dusky; with 2 rows of red spots and 2 rows of blue spots along back and with dim yellowish stripe between them. Gypsy. Page 34. 12. Hairy caterpillars, when grown with long pencils of hairs at each end; when young only sparsely hairy. I. Body white, black spotted, hair gray or white, with spreading tufts of white hairs and decorated down the back with a row of 8 black tufts. (fig. 17): Hickory tiger. Page 35. to Cc: T5 II. Body black, body hair yellow; more or less black at ends. Spotted tiger. Page 35. 13. Hairy caterpillars with soft hairy lappets low on the sides; a black band between joints 3 and 4 which shows when walking; warts on joint 3. Velleda lappet. Page 37. 14. A long-legged yellowish brown beetle feeding on the foliage. (fig. 18). Rose chafer. Page 38. Caterpillars living in web nests or cases in spring or summer, or. concealed in folded leaf or bud. 1. Dusky yellowish, hairy caterpillar usually with broad dark stripe along middle of back; body hairs long and dark; in colonies. (fig. 19). Fall web worm. Page 40. 2. Hairy caterpillar, ground color bluish, white stripe along middle of the back; in colonies. Orchard tent-caterpillar. Page 41. 3. Small bud-feeding caterpillar, with head and top of next segment black, body brownish. Bud Moth. Page 43. 4. Small smooth olive greenish or brownish caterpillar, with yellow head, black dot on each side of segment behind the head; lives in folded leaf in fall. (fig. 22). Leaf sewer. Page 44. 5. Caterpillar living in small cigar-shaped case (or from fall to early spring a curved case) about % inch long. (fig. 23). Cigar case bearer. Page 45. Conspicuous winter stages. Egg masses, cocoons, etc. 1. A small clump of dried leaves firmly tied together with s‘lk, fastened to the twig, concealing small dark living caterpil- lars within. (fig. 38). Brown-tail moth nest. Page 32. A large spindle-shaped cocoon upon the twigs with a single large brown pupa within. (fig. 37). Cecropia cocoon. Page 21. 3. A flat, oval, tan-colored, felt-like mass attached to tree trunks, old boards and all kinds of rubbish. Gypsy moth egg mass. Page 34. 4. A band of eggs encircling a twig. I. Egg mass with rounded ends. (fig. 36). Orchard tent-caterpillar eggs. Page 41 II. With square ends. Forest tent-caterpillar eggs. Page 30. 5. Eggs adhering to a grayish cocoon; cocoon enclosing a brownish empty pupal skin. (fig. 39). Antique tussock. Page 28. 6. A whitish frothy mass enclosing several layers of eggs adher- ing to a grayish cocoon, with empty pupal skin within. White marked tussock. Page 28. N 16 a, PLANT LICE Besides the woolly aphis which does its chief damage to the apple roots, several species of aphids attack the leaves, and tender stems. ‘These are minute insects about % of an inch long. They pierce the tissue of the shoots with their beaks and suck the sap or infest the leaves causing them to curl, or become sickly. Some species of these pass their whole life upon the apple while others spend part of the year on other plants. But as all the important species return to the apple twigs to lay eggs in the fall and as they resemble one another closely, both in appearance and manner of injury, it is not necessary to discuss more than two species here. Aphids are frequently attended by ants which are attracted by honey dew, a sweet secretion of the aphids, and the presence of ants about the apple leaves is a pretty certain sign of aphid infestation. Lady beetles (figs. 52, 53) both in the adult and larval stage feed greedily upon aphids and should not be mistaken for in- jurious insects. Syrphus maggots also are among the most beneficial insects in the State in this respect, as they destroy aphids in great numbers. I. GREEN APPLE APHIS. (Aphis pomi De G.) The body is pear-shaped, the colors being yellowish green, greenish, or darker, varying considerably in detailed markings and in the several generations. Winter eggs (fig. 30) are deposited by the sexual females in the fall. They hatch in the spring, and, like the species next considered, the aphids developing from them cause a curling oi the leaves. The green apple aphis infests the apple through- out the year. Upon the hatching of the winter eggs in spring a succession of agamic generations is produced, the earlier ones, except the first, with numerous winged individuals which migrate to other trees and establish new colonies. 17 2. Rosy Apple APHIS. (Aphis pyri Boyer.) ‘he rosy apple aphis, regarded by Gillette as possibly Aphis pyri Boyer, is readily distinguished from the preceding by its larger size, rounder body, and usually rosy color, which, how- ever, may vary from salmon to tan or even to slaty gray or biack, the body being covered with a whitish pulverulence. Winter eggs are deposited in the autumn by sexual females, and more often on the trunk and larger limbs than with the other species mentioned. They hatch in spring as the apple leaves are pushing out, and the young aphids infest the young leaves and later the tender shoots and foliage, the latter thus becoming usually badly curled. Three generations from the ege are said to occur-on the apple in the spring, many individ-- uals of the second and third generations developing wings and migrating to other trees and to other host plants. After the third generation the apple is deserted by the insects until fall, when the return migrants appear and give rise to the true sexual forms, the females depositing eggs as described... METHODS OF CONTROL. Pruning.—As has been stated, the aphids under considera-' tion pass the winter in the egg stage on the apple, the eggs being" deposited more or less promiscuously over the more nearly terminal twigs (fig. 30). With young trees especially, which are seen to be heavily stocked with the eggs, the latter may be largely removed during the work of pruning, and the prunings should be collected and burned. The insects in the egg condition are frequently distributed on nursery stock; therefore, if in planting trees this stock be well pruned and the prunings destroyed, the establishment of the aphids in young orchards may be often prevented or de- layed. Winter spraying for destruction of eggs—Excellent results have followed the use of lime-sulphur wash, most all of the eges of the apple aphis having been destroyed by one thorough application in spring shortly before the buds opened. The use of this wash for the eggs of aphids would also control the San Jose scale when present. 18 Spring and summer treatments—Effective work in control- ling these insects may be done in the spring just after they have hatched from eggs and have collected on the expanding foliage. Trees seen to be badly infested at this time should be thoroughly sprayed, taking pains to wet as completely as possible all parts of the leaves, twigs, and branches. However thoroughly the work may be done, some of the “lice” are almost sure to escape destruction, owing to the difficulty of forcing the spray between the unfolding leaves, more or less covered with hairs, where some of the insects will have penetrated. A subsequent treat- ment in the course of a week should usually be made, especially if the first application is seen to have been unsatisfactory. After the foliage is well out and more or less distorted from the presence of the aphids, effective spraying is quite difficult, since many of the insects on the lower surface of the curled leaves will not be hit by the spray. Repeated applications must be made, therefore, as necessary to keep the insects under con- trol. Spray mixtures.—The lime-sulphur wash for the destruction of winter eggs is made according to the usual formula for the wash (Formula 10). After the trees are in foliage, a more dilute contact insecticide must be employed, as strong tobacco docoction, 15 or 20 per cent kerosene emulsion, or whale-oil soap (Formulas 8, 4,6). Since aphids secure their food by sucking up sap from within the plant, none of the arsenical poisons would be effective. b. INSECTS FEEDING FREELY UPON THE LEAVES WITHOUT A NEST AND NOT CONCEALED WITHIN LEAF OR BUD. 1. CANKER WorMS. I, SPRING CANKER-WORM. (Paleacrita vernata. ) The male moths of this species have rather large, thin, silky wings, about one inch across when spread. The general color is bluish gray. A well defined row or band of light markings near the outer margin of the front wings, and three darker, irregular bands, across the same wings, together with the 19 slightly lighter color and absence of markings on the hind wings, are characteristic features. The inconspicuous female moths are wingless and, because of this fact, the spread of the species is very slow, occurring mainly by the transportation of nursery stock infested with eggs. The moths usually emerge from the ground early in the spring—about April, or farther south, in March—and the fe- males climb up the trunks of trees to deposit eggs. The eggs, which are shaped something like hens’ eggs and are about the size of fly specks, are deposited in irregular masses, usually partially concealed by loose pieces of bark. They hatch about the time the leaves unfold ; the time varying with the locality and the season. The larve are “measuring worms” with 2 pairs of legs at the hind end of body (fig. 5). The young larve are Fig. 5. a, larva, showing the two pairs of pos- terior legs; b, single egg, much enlarged. (After Riley). voracious feeders and they grow rapidly, usually attaining full size in from three to four weeks from the time of hatching. Upon reaching full size they drop to the ground, burrowing beneath the surface to a depth of two to five inches. Here each one forms a cell, lined with silk which it spins, and soon trans- forms to the chrysalis stage, where it remains until the following spring, when the adult moth emerges as before. Il, FALL CANKER-WORM. (Alsophila pometaria. ) The fall canker-worm so closely resembles the other species as to be frequently mistaken for it. For all practical purposes they may be considered together, but the fall canker-work is more distinctively a northern insect. As in the other species, the female moth is wingless, but in this species she lacks the hairiness which characterizes the other. The male moth has two light bands across the front wings instead of the single one of the preceding, and the rear wings are slightly shaded. The larve of this species also, besides having three pairs of legs under the hind end of the body, as shown in figure 6, have a broad, dark stripe along the back, as opposed to the narrow 20 markings of the other species. The eggs, which are slightly larger than in the previous species, somewhat resemble small flower pots and are attached to the bark, in exposed situations, im masses of from 60 to 200, placed side by side as seen in figure 6,¢. The eggs highly magnified, are shown in figure 6 a. Fig. 6. a, single egg, much en- larged; e, egg mass; f, larva, showing the three pairs of pos- terior legs. (After Riley). The eggs are deposited in fall or early winter (sometimes in mild winters as late as March). ‘They hatch about the same time as those of the other species and the larvze act in a similar manner, entering the ground about the same time. Instead of forming a cell lined with silk, however, this species spins a tough cocoon, and the moths come forth and begin laying eggs in October and November. HOW TO FIGHT CANKER-WORMS. One of the surest preventive measures is to place a band of tarred paper about the tree in March and smear it with tree tanglefoot, thus preventing the ascent of the female moths and the deposit of eggs. In case the bark is very rough, it should be scraped smooth to prevent the insects from crawling up be- hind the paper. If the fall canker-worm is present, of course the treatment must begin in October. If the trees are already attacked, jarring the limbs will cause many of the worms to spin a thread and drop to the ground. If the band of tangle- foot is in place they will be unable to return to the attack and may be destroyed. : The surest way of fighting this pest, however, is by spraying with Paris green or arsenate of lead (Formula 3). For this purpose the pump should be powerful enough to develop a pressure of at least 60 pounds to the square inch, and all parts should be made of brass and carefully adjusted. 2. Crcropra Mors. (Samia cecropia.) The large gray or brown cocoon of the Cecropia moth is fre- quently found attached to the twigs of trees (fig. 37). Fic. 7. (From Me. Agr. Exp. Sta. Circular). These are spun late in August or September by a green cater- pillar about four inches long. The body of the caterpillar is ornate with colored bead-like tubercles, the two pairs nearest the head being red with black spines, and the other dorsal tuber- cles smaller and yellow. Along the sides of the body the tuber- cles are bluish. (Fig. 7). After the cocoon’is spun the caterpillar changes to the pupa, a dark brown object which may be found by opening one of the cocoons during the winter. In the spring the insect breaks open the brown pupal skin and emerges from the cocoon as the adult insect, the largest moth in the state and one of the most beautiful. Its expanded wings measure about five and one-half inches. In color the wings are brownish with a border of gray and submarginal lines of white and red. The form of the markings is better represented by the accompanying illustration than by a descrip- tion. The caterpillar is well attended by insect parasites and is devoured by birds. In this State it has not occurred to a 22 troublesome extent and need not be feared as a pest, although it feeds on apple and various forest trees. No remedies usu- ally seem necessary. If the caterpillars are found upon a small trees which they are likely to injure, hand picking will prove effectual. Those who find the Cecropia cocoons during the winter are often interested to save them in a warm room for the sake of observing the beautiful moth which emerges (fig. 8). 3. YELLOW-NECKED CATERPILLAR. (Datana ministra.) During the late summer the yellow-necked caterpillar is a common orchard pest in Maine. The moth is tannish brown in color with head and the part of the thorax nearest the head a rich chestnut brown. Several dark brown lines cross the fore wings transversely. The hind wings are pale buff. The female moth deposits about 100 eggs in a cluster on a leaf. The caterpillars which hatch from these eggs, attain their full growth in 5 or 6 weeks. They are then about two inches long. The head is black and the segment just back of the 23 head is orange colored, a character which gives rise to the popular name “yellow-neck.” The body is striped longitudi- nally with alternate yellow and black lines. Soft white hairs occur over the whole body but are too thin to be especially noticeable (fig. 9). Like the red-humped caterpillar, these caterpillars are clustered together both while feeding and when at rest. The caterpillars when at rest assume a characteristic and peculiar position on the branch with both extremities of the body raised. When alarmed they jerk their heads and tails in an irritated manner. Fig. 9. (After Holland). The full grown caterpillars bury themselves in the earth a few inches below the surface, where they transform into brown pupz, unprotected by any cocoon. They remain in the earth all winter and emerge about the middle of the next summer, when they are transformed to the moth, or mature insect. REMEDIES. As in the case of the red-humped caterpillar, gathering the caterpillars by hand is the simplest remedy and perhaps the only one which it is necessary to recommend. The caterpillars are gregarious and the whole brood is easily removed from the tree and destroyed. Arsenical sprays (Formula 3) will kill them, and may sometimes be a convenient means of combating them. 4. ReEp-HuMPED CATERPILLAR. (Gdemasia concinna.) _ During August, September and October, the red-humped caterpillar is one of the most troublesome orchard caterpillars in the State. Many correspondents reported that entire or- chards of young trees were stripped of their foliage, except for the mid ribs of the leaves, before the presence of the pest had been discovered. 24 Fig. 10. (From Me. Agr. Exp. Sta. Circular). The mature insect is an inconspicuous brown moth with wing expanse of slightly more than one inch. The female deposits eggs on the under side of a leaf in a cluster, usually during July. The young caterpillars, which soon hatch from these eges, feed upon the tender tissues of the under side of the leaf, not attacking at first the upper surface. When they become larger they devour the whole leaf except the mid rib. They move in flocks, an entire brood feeding together and remaining in a cluster when resting. In the caterpillar or larval stage this insect is readily recognized. The body of the full grown caterpillar is marked with fine longitudinal stripes of black, white and yellow, and short black spines occur in rows. The head is bright red and the first segment of the abdomen, which is conspicuously humped, is of the same color (fig. 10). The caterpillars reach their full growth (about 11% inches) from August to late October. When full grown, they descend to the ground and hide under leaves or other rubbish and make a glassy transparent cocoon, within which they pass their pupal period. They remain in the cocoon all winter and emerge the following season as mature moths. REMEDIES. The red-humped caterpillars are not especially difficult to combat if a watch is kept for the colonies while they are young. As they are gregarious, it is a simple matter to clip off the small twig containing the whole brood of little caterpillars. When they are larger they can often be dislodged by jarring the branch and destroyed on the ground. Arsenical sprays (Formula 3) will kill them, hut the presence of fruit makes this remedy undesirable for bearing trees late in the season. 5. Morriep Fruir CATERPILLAR. (Crocigrapha normani. ) The eggs are laid in a mass flatly attached to the leaf. They hatch in mid-June in Maine. ‘The larva is a smooth, hairless caterpillar, 1% inches long when full grown. Its head is shiny 25 yellow with one dark blotch on each lobe. Its body is mottled grayish brown above, and pale grayish green beneath. The legs are pale. This caterpillar feeds both upon the foliage and the fruit. (See fig. 55). The pupal stage is passed in the ground. It is a glistening brown object about 34 inch long. The mature insect is a brownish moth expanding about 1% inches. REMEDIES. Arsenical sprays (Formula 3) applied for other species will control this one also. As this caterpillar is very readily dis- lodged, jarring the tree and killing the insect on the ground is a convenient combatative measure. 6. SADDLED PROMINENT. FHeterocampa guttivitta (Walker). This species is well known in Maine because it has been ex- cessively destructive to orchard and forest trees during some seasons. The full grown caterpillar is about 114 inches long; body green usually, with reddish brown markings on the back, smooth and hairless (fig. 11). The mature insect is a moth expanding about 2 inches, ground color olive-greenish ashen with cream white patches and black markings (figs. 12, 13). For Maine the saddled prominent has but one brood. The moths emerge in greatest numbers late in May and early in June. Oviposition begins soon after mating which occurs the first night after emergence. The eggs hatch in about 9 days and the larvee become full grown in 5 weeks (or more accord- ing to weather conditions and food supply). During this time they molt four times. The full grown larve enter the ground for pupation. In Maine pupation takes place from mid July to late August, the majority of larve burying late in July. They pass the winter in the pupal stage, under the leaf mold, and the moths emerge in the spring. The eggs are deposited singly by the female which in cap- tivity applies the eggs to both sides of the leaf. From the rea- son that the tops of the trees are stripped first and then the lower branches it is to be concluded that the moths by prefer- ence deposit the eggs upon the upper leaves. Perhaps the same tendency to fly high may account in part for the fact that the 26 hillside forests are in general more largely attacked than the lowlands. The full grown larva drops or climbs to the ground and con- structs a cell in the earth or under the leaves at a distance of I to 3 inches below the surface. This cell is oval and is lined by a thin spinning of silk. The insect after remaining in the pupal stage all winter emerges with the warm spring days. Hic. arr, (CAtter Packardi)r Fic. 12. Male. Fic. 13. Female. (Fic. 12 and 13 from Me. Ag. Exp. Sta. Bul. 161). COMBATATIVE MEASURES. For the orchard or shade trees there are several practical measures which have proven successful the past season in pre- venting serious injury from the saddled prominent. Spraying.—This species is susceptible to arsenical poisons and the caterpillars readily died on apple trees which were thor- oughly sprayed. Arsenate of lead or Paris green (Formula 3) will kill these caterpillars and should be applied as soon as they begin appreciable work. Applications from the middle to the last of Jurie would probably get all these caterpillars which hatched upon the trees. In case a migration to an orchard from an infested forest growth is feared, the orchard should be sprayed as soon as the caterpillars begin to travel in search of fresh food. If trees not already attacked are banded with a sticky substance, the ascent of caterpillars up the trunk will effectually be prevented. 27 Jarring and banding—The saddled prominents are readily shaken from the branches. The cool of the morning is the most propitious time for jarring. The caterpillars once dis- lodged, their reclimbing can be prevented by banding. A material useful for this purpose is sold under the name of Tree Tanglefoot. ‘This substance consists principally of resin softened by the admixture of suitable oils. It is quite similar to that used in the manufacture of adhesive fly-paper, seems to possess the merit of not injuring the trunks of trees, and is very effective in checking the ascent of caterpillars thereon. Where the number of caterpillars jarred from the trees is excessive it is expedient to kill them. A hand spray charged with kerosene or gasoline is a useful means to this end. Fowls and Pigs——Hens will devour these caterpillars greedily and if given the range of an orchard will eat great numbers of the caterpillars which drop to the ground or descend to pupate. Pigs pastured in an orchard will, by rooting up and eating the pupz, prevent great numbers of saddled prominents and other moths from emerging and depositing eggs for the follow- ing season. 7. AppLE-LEAF BUCCULATRIX. (Bucculatrix pomifoliella.) The larva of this insect is about one-half inch long when mature, cylindrical, tapering at both ends. Joints of the body rounded and prominent, color dark yellowish, with a greenish tinge and reddish shades on the anterior segments. The larve are active and when disturbed suspend themselves by a silken thread. The cocoon is dirty white, slender, about one-fourth inch long, ribbed longitudinally by about six prominent ridges, oblong, tapering at both ends, flattened on the side to which it is at- tached. Usually fastened to the twigs and branches in groups. (Fig. 14). 28 Fic. 14. (After Riley). The small moth has only about one-fourth inch expanse of wings. Fore wings whitish, tinged with pale yellow and dusky brown. (Fig. 14). This insect spends the winter in the pupa state in the cocoon, usually attached to the twigs and branches of the host plant. About the time the leaves unfold, the moths come forth and lay their eggs upon the tender foliage. The larve are full grown in July. In September or October the cocoons in which the pupe spend the winter are formed. The larve feed externally upon the foliage, the upper epidermis and pulp eaten away in patches, the veins and lower epidermis intact. REMEDIES. Jar the trees when the larve are full grown and they will suspend themselves by threads and can be swept down by a broom and killed by hot water or crushed. Apply kerosene emulsion with a spraying pump in winter, to the branches that bear the cocoons. The same application might be made for the first brood when the foliage is on. Spray with arsenical poisons (Formula 3) as for other leaf- eating insects. 8. Tussock Morus. I, WHITE-MARKED TuUSSOCK (Hemerocampa leucostigma). Il, ANTIQUE TussocK (Notolophus antiqua). The conspicuous white egg masses of these moths are de- posited late in the summer or in the fall upon the cocoons from 29 which the female moths emerge. As the hairy cocoons are commonly attached to the rough bark, or twigs of trees the caterpillars infest, the egg-masses are readily found at any time after the leaves have fallen. The eggs which the white-marked tussock deposits are covered with a white frothy substance which becomes brittle upon exposure to the air. The antique tussock does not protect its eggs in this manner but leaves them uncovered upon the cocoon (fig. 39). Fic. 15. (After Riley). The caterpillars which emerge from these eggs in the spring are most grotesque in appearance. ‘The caterpillar of the white- marked tussock moth when full grown has a shiny coral red head beyond which extend two stiff pencils of black hairs di- rected forward like horns. A single pencil of similar con- struction supplies the other end of the body with a tail. Upon the middle of the back, starting a little behind the head, is a row of four regular tufts of soft whitish hairs which resemble small paint brushes neatly trimmed off at the tip. In a line with these but nearer the tail occur two little bright red tuber- cles (fig. 15). The full grown antique tussock caterpillar re- sembles closely the species just described. Its head, however, is jet black and it has an additional pair of black pencils, simi- lar to though shorter than the horns, projecting from the sides of the body, which is lacking in the caterpillar of the white- marked tussock. After feeding for four or five weeks the caterpillar becomes full grown and spins a rough cocoon of silk with which it mixes the hairs that have decorated its body. These cocoons are usu- ally formed upon the bark or in the angles of twigs. Often a leaf is attached to the mass. In about two weeks the adult insects emerge from the co- coons. The males are winged, the white-marked tussock having gray wings which expand nearly one and one-half inches and the antique tussock having smaller brown wings. The female 30 moths of these two species are not readily distinguishable. They never acquire wings and their distended bodies are practically little more than animated sacs of eggs. The females being un- able to fly and their bodies being too heavy for their slender legs to drag about, cling to the cocoons from which they emerge and soon after mating deposit about 300 eggs in a mass upon the cocoon. REMEDIAL MEASURES. The white egg masses deposited on the cocoons remain on the trees all winter. These are readily seen and can be removed and burned. Cocoons of the tussock not covered with eggs should not be disturbed as they are either the empty cocoons of males or cocoons containing parasites. If the cocoons are empty they can do no harm and if they contain parasites, these insect enemies of the tussock should be allowed to develop. The fact that the females cannot fly makes this pest easily controlled locally, for the orchardist need not especially fear his neighbor’s infested trees. The caterpillars are susceptible to arsenical sprays (Formula 3) and this means of combating them is sometimes necessary where the winter collecting has been neglected or when the tus- socks appear in destructive numbers upon shade trees. 9. Forest Tent CATERPILLAR. (Malacosoma disstria.) The eggs of this insect are deposited in a belt encircling a small twig, about 200 in each mass. These egg masses resemble those of the orchard tent caterpillar, except that they are more nearly square at the ends. A glistening varnish-like protective substance is deposited with the eggs which renders the mass more readily seen in the sun. The colonies of young larve do not construct tents as do the orchard tent caterpillar, but they are usually massed during dark or rainy weather. The caterpillars resemble the orchard tent caterpillars, the most striking difference being that the cream colored line along the back is broken into a line of dots in the forest tent cater- pillar while with the orchard tent caterpillar this line is un- broken. They grow to be about two inches long. 31 The full grown caterpillar constructs a filmy outer cocoon with an inner firm cell which it soaks with a yellow discharge drying to a pale yellow powder. These cocoons are often at- tached to buildings. Moth.—In from 1o to 14 days after spinning the cocoon the adult insect emerges. This yellowish-brown moth resembles that of the orchard tent caterpillar closely but the transverse bands on the wings are darker than the ground work of the wings instead of paler as with the other species. It is not practicable to combat the insect in this stage. REMEDIAL MEASURES. Arsenical sprays (Formula 3) applied early in the season will satisfactorily dispose of this pest and for orchard or shade trees protected in this manner no other means are necessary. After the caterpillars are half grown it is their custom to congregate in great masses on the trunks of the trees while they molt their skins. Here they may be destroyed by a stiff broom dipped in kerosene or swept into a pail of water and kerosene. When not congregated for molting the older caterpillars when not feeding stretch out motionless along the branches or trunk and are difficult to see, especially as they are likely to choose the upper side of the branch. However, it is not necessary to wait for the molting periods in order to combat the older caterpillars on trees which have not been protected by spraying. ‘These caterpillars drop down- ward when disturbed. “This habit leads to the suggestion that by a combination of jarring and banding much injury may be prevented.” After the caterpillars are jarred from the tree the trunks of trees are painted with a band of “tanglefoot” such as is used against the gypsy caterpillar to prevent their ascending. L Fic. 16. Forest Tent Caterpillar. (From. Me. Ag. Ex. Sta. Circular). 32 10. Brown-Tait Mora: (Euproctis chrysorrhea.) The caterpillars of the brown-tail moth are capable of ruin- ing orchard, shade and many woodland trees. They are also a dreaded nuisance, because the caterpillar hairs break off, and on coming in contact with the human skin, cause extreme irri- tation and often illness. So serious a pest should be known by every one in the State, because although extermination of this insect may not be pos- sible, much practical and effectual work can be done in holding it in check and reducing its numbers so that damage to orchard and shade trees may be very slight. The moths, expanding from one and one-fourth to one and three-fourths inches, are white except for the abdomen, which is tinged with brown and tipped with a tuft of brown hairs. This tuft is small and dark in the male, but the large golden- brown tuft in the female is conspicuous enough to be the most striking characteristic of the moth, and has won for this insect — its descriptive name of “brown-tail.”” These moths are on the wing in July, and unlike some closely related pests, the brown- tail females as well as the males are strong fliers. They are active at night, and as lights have an attraction for them, they sometimes fly a long way toward a lighted district. The female usually selects a leaf near the tip of the branch on which to deposit from one hundred and fifty to three hun- dred eggs. Some of the brown hairs from the abdominal tuft adhere to the egg-mass and give it the appearance of a brown felt lump. | By the middle of August most of the eggs are hatched and the young caterpillars spin a slight web over the leaf near the egg cluster. When they have eaten all but the skeleton of the first leaf, they draw another into the web and repeat the process. at intervals during the late summer. They feed slowly, how- ever, and spend so much time spinning their web that they do comparatively little damage to the trees in fall, and they are still. very small (about one-fourth of an inch in length) when cold weather comes on. The winter nests —(Fig. 38). In the fall the young cater- pillars weave additional layers of silk about their retreat, fas- a3 tening it securely to the branch by the web, and pass the winter thus in colonies of one hundred and fifty to three hundred in a single nest. This is a very unusual yet most commendable habit in a caterpillar pest, for they can be killed, hundreds at a time, simply by burning the nests in which the colonies hiber- nate. The nests, composed of leaves, bound firmly together by a silken web, are varied in shape. In spite of the superficial variety the essential characteristics of the brown-tail moth nests are soon learned, and even anyone unfamiliar with the nest can make himself perfectly certain if he will cut carefully into the nest. If the structwre contains one or more silken cells filled with tiny living caterpillars it 1s the winter nest of the brown- tail moth, Early in the spring the young caterpillars emerge from their winter nests and feed upon the opening leaf buds. Until about the middle of June they feed greedily upon the leaves, com- pletely stripping the trees where they are numerous. When full grown the caterpillars are about one and one-half inches long. They are dark brown with a sprinkling of orange. Long fine reddish-brown hairs cover the body, and a row of conspicu- ous white hairs runs along each side. Like the caterpillars of the tussock and gypsy moths, they bear bright red tubercles on the top of the sixth and seventh abdominal segments. Poisonous qualities of the caterpillars——Were the caterpillars to be feared only for their ravages upon orchard and other trees, the situation would be alarming enough, but not less serious is the physical discomfort experienced by people living in infested districts. When the minutely barbed hairs of the caterpillar come in contact with the skin they cause an eruption similar to and in many cases worse than ivy poisoning. These hairs are brittle and where the caterpillars are numerous few people are likely to escape, as the caterpillars drop from the branches and creep about, even entering houses. Direct con- tact with the insects themselves is not necessary, however, for when the caterpillars shed their skins the molts are blown about, widely scattering the barbed hairs. The caterpillars are usually full grown in-June. They then spin loose cocoons, attached commonly to leaves, though some- times other shelter is sought. Within these they transform to 34 brown pupz about three-fourths of an inch long. From the first to the twentieth of July the moths with pure white wings and brown-tipped abdomens emerge from these cocoons to deposit eggs for the next generation of caterpillars. REMEDIAL MEASURES. Destruction of breeding places—Old and worthless orchard trees, wild cherry tangles and other susceptible trees in infested regions should be cleared away, thus lessening the labor of direct search for the destruction of winter nests, by eliminating likely breeding places. Cutting and burning the winter nests—This is the most im- portant of the direct remedies because it is the easiest, cheap- est and, if thoroughly done, a sufficient protection against the ravages of this pest. The webs and leaves that compose the rest are woven tightly to the tips of the branches and hang there like dead leaves all winter. With so many months for inspection there is no excuse for harboring the hibernating caterpillars on shade or orchard trees. After they are cut from the branches the nests should be burned, as this is the simplest way of destroying the colony within. Spraying—The young caterpillars can be killed by arsenical sprays (Formula 3). This remedy is most effective when ap- plied as soon as the leaves develop in the spring. Of course where the winter nests have been destroyed there will be no need of this remedy and it is much easier to kill about two hun- dred caterpillars enclosed in a nest than to wait until they are scattered over the tree. rr) Gypsy, Mors. (Lymantria dispar.) Unlike the brown-tail moth, the gypsy moth winters in the egg stage. Although winged, the female gypsy moth does not fly, but deposits the eggs in any convenient place to which it can crawl. The egg masses are most commonly attached to the bark of trees but they are also found in such places as under edges of stones, beneath fence rails, on buildings, and in old cans and rubbish. The eggs are laid in July and August in a mass of 400 to 500. ‘They are covered with tan colored hairs from the body of the female moth, and form an irregular oval mass. 35 As the eggs do not hatch until about May 1, eight months at least are available for their destruction. The young larve or young caterpillars are dark in color and well furnished with dark hairs. The full-grown larva is be- tween 2 and 3 inches long, dark brown or sooty in color, with two rows of red spots and two rows of blue spots along the back, and with a yellowish but rather dim stripe between them. The body generally is clothed with long hairs, and sometimes reaches the length of 3 inches. The larve usually become full grown about the Ist of July, and then transform to pupe. The pupz are found in the same situations as those we described for the egg clusters, but are found also in the foliage of trees and shrubs. The male moth is brownish yellow in color, sometimes having a greenish-brown tinge; it has a slender body, well-feathered antennz, and a wing expanse of about an inch and a half. The forewings are marked with wavy zigzag darker lines. It flies actively all day as well as by night. The female moth is nearly white, with slender black antenne, each of the forewings marked with three or four zigzag, trans- verse, dark lines, and the outer border of both pairs of wings with a series of black dots. The body of the female is so heavy as to prevent flight. REMEDIAL MEASURES. Killing the Eggs—‘No single method of destruction against the gypsy moth is more effective than killing the eggs. The egg masses, wherever accessible, can be killed from August to May by soaking them thoroughly with creosote mixture. The creosote may be applied with a small swab or paint brush. Creosote mixture may be purchased at agricultural warehouses and seed stores at from 50 cents to $1.00 per gallon, depending on the quantity.” The caterpillar can be controlled by arsenical sprays (For- mula 3). 12. Tickr Morus. I, HICKORY TIGER MOTH (Halisidota carye). Il. SPOTTED TIGER MOTH (Halisidota maculata). These two closely related insects are so similar in habits and 36 are so commonly associated in Maine orchards that they may be discussed together. The hickory tiger caterpillars are, when full grown, covered with spreading tufts of white hairs and decorated down the back with a row of 8 black tufts. The fourth and tenth seg- ments each bear two long slender pencils of black hair. The caterpillar of the spotted tiger moth is yellow and black, these colors occurring in widely variable proportions. Some- times the whole body is covered with yellow hairs in which case there is a row of 8 tufts of black along the back as with the hickory tiger. Often, however, both ends of the caterpillar are covered with black hairs with scattering pencils of white and the yellow hairs are limited to the central portion of the body. Both the hickory tiger and spotted tiger caterpillars have jet black heads and legs. The young tiger caterpillars are only sparsely supplied with hairs and bear very little resemblance to the fuzzy full grown ones. ‘They are gregarious when young and at first their pres- ence may be detected by skeletonized leaves but later the colony scatters and the caterpillars feed separately, eating the whole leaf substance. If they are disturbed they curl up like a hedge- hog and drop to the ground. The hairs are easily brushed from the body of these caterpillars and cause, upon contact with sen- sitive