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marked as at h. in the figure. The cocoon is invariably of a pure white color on the inside, but is disguised on the outside by being covered with minute fragments of whatever substance the worm happens to spin to. The chrysalis is yellowish-brown, with rows of minute teeth on its back, by the aid of which it is enabled to partly push itself out of its cocoon when its time to issue as a moth arrives. The moth is a most beautiful object. Its fore-wings are marked with alternate, irregular, transverse wavy streaks of ashgray and brown, and have on the inner hind angle a large tawnybrown spot, with streaks of bright bronze color or gold." The moth is seldom seen, as it flies in the evening. The "worm," as it is called, is a caterpillar, and may be known from other apple-eating larvæ by its having six horny legs near the head, eight fleshy legs near the middle of the body, and two near the hinder extremity of the body.
The codling-moth is usually two-brooded, the second brood of worms passing the winter in a larval state, within the cocoons, and protected further by the bark, or other shelter beneath which the cocoon is usually attached. These larvæ are hatched about the time of the blossoming of the apple. The moths soon pair, when the female deposits its egg in the calyx of the apple. This occurs about the time of the dropping of the blossom. The worm eats its way to the center of the fruit, and through the fleshy portion, gradually developing until it has reached its larval growth. Riley says “In thirty-three days, under favorable circumstances it has become full fed; when leaving the apple, it spins up in some crevice; changes to a chrysalis in three days, and issues two weeks afterwards as a moth, ready to deposit its eggs again, though not always in the favorite calyx this time, as I have found the young worm frequently entering from the side." The time required for the hatching of the chrysalis, varies considerably, depending upon the temperature, being shorter as the weather is warmer. Mr. Riley says, " while some of the first worms are leaving the apples, others are but just hatched from later deposited eggs, and thus the two-broods run into each other, but the second brood of worms (the progeny of the moths that hatch out after the first of July) invariably passes the winter in the worm or larval state, either within the apple after it is plucked, or within the cocoon.”
REMEDIES.—The greater portion of fruit infested by the worm,
falls before the worm has left it. Hence, any means of destroying this fruit will, in so far as it contains the worms, diminish their numbers. This may be done by allowing hogs to run in the orchard to eat the fallen fruit, or such fruit may be picked up by hand, and scalded or fed to swine. But as many worms escape from the apples before falling, and many more would doubtless escape after falling and before being destroyed, this means of destruction is at best only a partial preventive.
A much more effectual method is to entrap the larvæ by placing something convenient beneath which they will spin their cocoons. I quote again from Mr. Riley. “This can be done by hanging an old cloth in the crotches of the tree, or by what is known as Dr. Trimble's hay-band system, which consists of twisting a hay-band twice or thrice around the trunk of the tree." To make this system perfectly effectual, I lay down the following rules:
1. The hay-band should be placed around the tree by the first of June, and kept on until every apple is off the tree.
2. The hay-band should be pushed up or down and the worms and chrysalids chrushed, that were under it, every week, or at the latest, every two weeks.
3. The trunk of the tree should be kept free from old, rough bark, so as to give the worms no other place of shelter.
4. The ground itself should be kept free from weeds and rubbish.
"But as already stated, many of the worms of the second brood yet remain in the apples even after they are gathered for the market. These wormy apples are barrelled up with the sound ones, and
the cellar or barn. rom them the worms continue to issue, and they generally find plenty of convenient corners about the barrels in which to form their cocoons. Hundreds of these cocoons may sometimes be found around a single barrel, and it therefore becomes obvious that, no matter how thoroughly the hay-band system had been carried out during the summer, there would yet remain a sufficiency in such situations to abundantly continue the species another year. And when we consider that every female moth which escapes in the spring, lays from two to three hundred eggs, and thus spoils so many apples, the practical importance of thoroughly examining, in the spring of the year, all barrels or other vessels in which apples have been stored, becomes
at once apparent. It should, therefore, also be made a rule to destroy all the cocoons which are found on such barrels or vessels, either by burning them up or by immersing them in boiling water.
The philosophy of the hay-band system is simply that the worms in quitting the fruit, whether while it is on the tree or on the ground, in their search for a cozy nook in which to spin up, find the shelter given by the hay-band just the thing, and in ninety-nine cases out of a hundred, they will accept of the lure, if no other enticing be in their way." Old pieces of sacking, and bands of two or three thicknesses of strong brown paper, tacked closely around the tree, have often been substituted for the hay-bands, with success, while they require less tme in preparation. There is no doubt that this system, carefully carried out, will greatly diminish the number of wormy apples, and if generally adopted by a neighborhood would in a short time nearly exterminate this great pest. The one thing necessary is, that every man who has bearing apple trees, should attend to this business in its season, and in a short time the number of moths would be so reduced as to make the keeping them in check a much less serious business. Let no man wait to begin another year.
THE CANKER-WORM, (Anisopteryx rernata, Peck. Palecrita vernata, Riley). This insect which has done so great injury to fruit and shade trees in the eastern States, has become well established in many localities in Wisconsin. Unlike the codling-moth, it attacks the trees rather than the fruit, and attacks the plum, cherry, and elm, as well as the apple.
The male moth, Fig. 2, u, is winged; the female, b, is wingless. The wings of the male are ash-colored. The fore-wings are crossed Fig. 2.
by three jagged, dark lines (Riley), they expand about one and one-fourth inches. Late in autumn, and early in the spring, the male flies about,
and pairs with the wingless female. "Soon after, the wingless female lays her eggs upon the branches of the trees, placing them in rows, forming clusters of sixty to one hundred, the number usually laid by each female. The eggs are glued to each other and to the bark, and the clusters are thus fastened securely in the forks of the small branches or close
to the young twigs or buds. The eggs are usually hatched between the first and the middle of May, or about the time that the red currant is in blossom, and the young leaves of the apple tree begin to start from the bud and grow. The little canker-worms, upon making their escape from the eggs, gather upon the tender leaves, and, on the occurrence of cold or wet weather, creep for shelter into the bosom of the bud, or into the flowers, when the latter appear.”. (Harris' Insects Injurious to Vegetation.)
These worms belong to the group known as geometers, spanworms, or measuring-worms, so called from their having legs only at the extremities of the body and the consequent method of progression by first reaching forward and grasping with the fore-legs, and looping the body as the hind-legs are brought forward. “This worm when mature is about an inch long, ash-colored on the back, black on the sides, and beneath yellowish." (Packard.)
Figure 3, a, full grown larva; b, egg enlarged, the natural size shown in small mass at the side; c, an enlarged joint, side view; d, Fig. 3.
the same, back view, showing the markings. The larvæ vary greatly in the intensity of their markings. They cease eating when about four weeks old, which in this latitude would usually be during the
last half of June. It then creeps down the trurk of the tree, or lets itself down by a thread, and burrows in the earth, from two to six inches in depth, where it forms a rough, earthy cocoon, and changes to a crysalid.
It remains in this condition until late in the autumn, or the following spring. Harris says, "the occurrence of mild weather, after a severe frost, stimulates some of these insects to burst their chrysalis skins and come forth in the perfected state." A severe frost seems to be necessary to this change from the chrysalis to the moth, and such change may occur during any period of mild weather during the late fall, winter, or spring. They come out of the ground mostly in the night, when the female instinctively crawl to the nearest tree, during the ascent of which the male usually finds her, and the coupling occurs. After laying her eggs, as above stated, the female dies.
The remedy for this insect is founded upon the wingless condition of the female. Her only object is to deposit eggs for another
generation of worms. These eggs must be deposited near the food, that is to nourish the young larvæ, that is upon the limbs of the trees. The female moth can only reach these limbs by crawling up the trunk of the tree, hence any means that will prevent this ascent will be an effectual remedy, except as the newly hatched worms may be able to pass such barrier. Many methods have been devised to accomplish this object, but that which is at once the cheapest and most effective, is the application of a semifluid, adhesive substance, either directly upon the body of the tree, or better. if care is taken to make such bandage close to the tree, that nothing may pass behind it, upon coarse cloth or paper. Tar, refuse printer's ink, melted india rubber, molasses, have all been recommended. The essential condition is, that the substance shall be soft and sufficiently viscid to entangle and hold the feet of the female moth. Tar hardens quickly and needs to be renewed often; melted rubber retains its viscidity, and is consequently much better. The remedy must be applied during warm weather, after the first severe frost in the fall, usually as early as the middle of October, and the application must be kept sticky by renewals during all warm weather, until the trees are in full leaf the following spring. As application of many adhesive substances directly to the bark, may prove injurious to the tree, it is always safer to make the application as before stated, upon cloth or paper closely bound about the trunk. On account of its habits, the canker-worm is much more local than the codling moth, and each fruit-grower is much less dependent upon the conjoint efforts of his neighbors for its extermination, than with that insect. There are many methods, , however, by which it may spread from orchard to orchard, even though the female be wingless. The most ready means is doubtless by carrying the larvæ, as they are caught when spinning down from the tree, by passing carriages, upon the backs of animals or man, or by umbrellas, etc. Yet by careful and determined effort, when once they have become established, they may be entirely eradicated in two or three years.
There are several natural insect enemies of the canker-worm. Among these are several species of ichneumon-flies, a large groundbeetle (calosama scrutator), having beautiful golden-green wing