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 larvæ soon hatch, eat
through the bark, and burrow in the outer surface of the wood just
under the bark.