Rensselaer Union, Volume 7, Number 31, Rensselaer, Jasper County, 22 April 1875 — The Tellow-Necked Apple-Tree Caterpillar. [ARTICLE]

The Tellow-Necked Apple-Tree Caterpillar.

To every orchardist the larva of the Datana ministra is known, yet few are able to recognize the moth itXelf. It belongs to that family of Lepidoptera called Notodontidse; is seldom seen, and, if seen, only recognized by those who have known it before. It measures, when the wings are expanded, from one and a half to two and a fourth inches. The moth varies in color according to the food previously fed upon; and, since the larva feeds upon the leaves of the apples, cherry, quince, oak, hickory, and numerous other trees, the color of the moth varies.. The under wings are much lighter in color than the upper, being usually of a pale-yellowish or whitish ■ color; the posterior margin of a deeper color. Thfe upper wings vary from bright yellow to smoky brown, crossed by four or five narrow bands. The body itself is*of a yellowish color, sometimes inclining to red. The larva, when fully grown, is generally about two inches long; those feeding on the leaves of the apple being covered with white hairs as long as the body is wide. . They vary with the food eaten, but are generally found of a black color, with four yellowish stripes on each side of the body. The eggs are deposited on’“'the under side of the leaves, in a dense patch, nearly 100 in number; these are white and round. As soon as hatched the larvie commence eating the under side of the ’leaves; but as they increase in size they eat the entire leaf, except the midrib. They do not spin a common web, as the tent-caterpillars do, yet they are strictly gregarious, eating from one branch or twig until the leaves are all consumed and then migrating to another. The most interesting feature of these larva; is during the molting season when they all come down upon the trunk of the tree cling in one body to the bark, assisted in this position by a silken thread passed among them. They remain in this position without food usually two days and toh nights, when they cast oft their old skins and commence crawling up the trunk of the tree to their food, leaving the old empty skins attached to the tree. I have observed them on the hickory, cling to one of the upper branches, when molting, instead of coming down; but this is only the case when the tree is old enough for the branches to become as large as that of a common-sized tree. When suddenly alarmed they assume a peculiar position by throwing the head and tail at right angles with the rest of the body; and that is alsp observed when nesting. They have six true legs and eight prop legs—the last-mentioned disappearing lyhen changed to the moth. When they become fully grown their social habits change and for the first time they separate and wanuer off alone before entering the pupa state. Their larvie do not make their appearance until midsummer and remain until the frost has destroyed the leaves in the fall. They remain in the pupa state during the winter, changing to the moth state when warm weather comes. Owing to the fact that they eat the entire leaves upon a branch before migrating to another the tree depredated upon assumes an unsightly appearance when cultivated for shade of ornament; but upon the ap-ple-tree it decreases its vigor and thereby lessens the, value of the fruit. Therefore care should be taken that they be destroyed. This can easily be done, during any of the molting seasons, by detaching the caterpillars from the trunk or limb and burning or scalding them. There are but few birds that feed upon this insect in the larva state, therefore fruit-growers should depend principally upon their own exertions for the destruction of this enemy to the orchardist. — Cor. Chicago Tribune.