On the approach of winter, it descends to the lower part of its burrow, where it remains inactive until spring. The second season it continues its work in the sapwood, and in case two or three are at work in the same tree may completely girdle it, thus destroying it. The third year it penetrates to the heart of the tree, makes an excavation, and awaits its transformation. The fourth spring it comes forth a perfect beetle, and lays its eggs for another generation.
The flat-headed apple tree borer, Chrysobothris femorata, is also a native of this country. It is a very active insect, delights to bask in the hot sunshine; runs up and down the tree with great rapidity, but flies away when molested. It is about half an inch in length. “It is of a flattish, oblong form, and of a shining, greenish black color, each of its wing cases having three raised lines, the outer two interrupted by two impressed transverse spots of brassy color dividing each wing cover into three nearly equal portions. The under side of the body and legs shine like burnished copper; the feet are shining green.” This beetle appears in June and July, and does not confine its work to the base of the tree, but attacks the trunk in any part, and sometimes the larger branches. The eggs are deposited in cracks or crevices of the bark, and soon hatch. The young larva eats its way through the bark and sapwood, where it bores broad and flat channels, sometimes girdling and killing the tree. As it approaches maturity, it bores deeper into the tree, working upward, then eats out to the bark, but not quite through the bark, where it changes into a beetle, and then cuts through the bark and emerges to propagate its kind. This insect is sought out when just beneath the bark, and devoured by woodpeckers and insect enemies.
Another borer, the long-horned borer, Leptostylus aculifer, is widely distributed, but is not a common insect, and does not cause much annoyance to the fruit grower. It appears in August, and deposits its eggs upon the trunks of apple trees. The larvae soon hatch, eat through the bark, and burrow in the outer surface of the wood just under the bark.
The practical point is, What remedies can be used to prevent the ravages of the borers? The usual means of fighting the borers is, to seek after them in the burrows, and try to kill them by digging them out, or by reaching them with a wire. This seems to be the most effectual method of dealing with them after they have once entered the tree, but the orchardist should endeavor to prevent the insects from entering the tree. For this purpose, various washes have been recommended for applying to the tree, either for destroying the young larvae before they enter the bark, or for preventing the beetles depositing