tail 
The More Important Apple Insects. 73 
The borer with a 2-year life cycle eats out a burrow during the summer, form- 
ing at its end the pupal chamber in which it pupates the following spring, 
whereas the insect with a 3-year cycle feeds within the solid wood for another 
season and then prepares its pupal cell from which the adult issues the follow- 
ing year. 
Worming trees by means of a knife and wire to hook out the larva from its 
burrow is the method of control most frequently practiced. The position of 
the gallery is best located by means of the stringlike mass of reddish castings 
pushed out at the base of the tree. When the larva is in the pupal chamber it 
can not be readily reached by the wire because the gallery is plugged with 
woody tissue; in this event a small piece of cotton saturated with carbon disul- 
phid may be inserted in the burrow, after which the hole should be plugged 
with moist earth so as to confine the fumes. If worming is done regularly 
each fall as soon as possible after the eggs have hatched, and special attention 
given to finding and destroying the young borers still working in the sapwood, 
the task of worming will be lightened and the more serious injury to the tree 
from older borers avoided. 
In the latitude of Washington, D. C., worming as a rule should be completed 
before September, while farther south it may be done a month or so earlier, and 
in the North it may be deferred until the middle of September. 
Host plants other than cultivated fruit trees should not be allowed to grow 
near the orchards, since they serve as breeding grounds for the beetle. 
Paints and washes are sometimes used to deter the beetle from ovipositing. 
- Various results have been obtained from their use. If paint is employed, it 
should be of pure white lead and raw linseed oil mixed to a consistency some- 
what thicker than that used in general painting. The earth should first be re- 
moved from the base of the tree to a depth of 3 or 4 inches and the bark scales 
and dirt scraped from the trunk for a distance of about a foot above the ground. 
The paint should then be applied to the prepared part of the trunk with a 
brush, and after it has dried the earth should be replaced. 
Tree-protectors made of newspapers, building paper, wood veneer. and ecyl- 
inders of fine-meshed wire screen, the tops of which have been plugged with 
cotton, are sometimes used to prevent the beetle from ovipositing around the 
base of the trees. 
The arsenical sprays regularly used in commercial orchards against other in- 
sects are of some value in killing the adults, which feed to a certain extent upon 
the leaves and twigs as described. 
FLAT-HEADED APPLE-TREE BORER.” 
The flat-headed apple-tree borer is second in importance to the roundheaded 
borer and, unlike the latter, seldom attacks vigorous, healthy trees. It will, 
however, infest those that are weakened from various causes, particularly trees 
that lean strongly one way (fig. 150), thus exposing a portion of the trunk to 
the sun, where the beetles freely oviposit. The larva or borer (fig. 151) causes 
injury to apple trees (fig. 152) by feeding between the bark and sapwood of the 
trunk and larger branches. On young trees a single borer may nearly or 
actually kill them, especially newly plantedetrees that fail to start off right. A 
related species“ is frequently complained of on the Pacific coast on account 
of its injuries to young trees. The larve usually are present on the sunny side 
of the trees, especially in the case of large ones, and the dead area may be 
enlarged from year to year by successive generations eating out the fresh tis- 
6 Chrysobothris femorata Fabricius. % Chrysobothris mali Horn. 
