INSECT AND FUNGOUS ENEMIES OF THE APPLE. 9 
smooth surface. The average time required for the egg to hatch is 
about 11 days, the time varying considerably, however, with the 
temperature. 
The larva.—It is in the larval or “ worm” stage that injury is done 
to the apple. The larva as it hatches from the egg is very small, 
from one-twentieth to one-sixteenth of an inch in length, but it soon 
begins to search for the fruit. If hatched from eggs placed here 
and there on the foliage, the larvee chew more or less into the leaf 
or other portions of the plant in their wandering around and may 
thus be poisoned, if poison be present on the plants. If the eggs 
have been deposited on the fruit itself the larve are much more likely 
to gain entrance to the fruit. Larve entering the fruit by the calyx 
end feed within the calyx cavity for a few days before penetrating 
the fruit. Hence the advantage of thoroughly spraying trees shortly 
after the petals have fallen and while the calyx lobes are still spread, 
in order to place in each calyx cavity a small particle of poison to be 
eaten later by the !arva as it seeks to enter the fruit. 
After entering the apple the larva feeds and grows rapidly and 
in the course of about 20 days has become full grown. (See fig. 2, 0.) 
At this time the * worms” are about three-fourths of an inch long, 
and the majority of them are pinkish or flesh colored on the upper 
surface and whitish below. 
The pupa.—The full-grown larva, upon leaving the fruit and find- 
ing a protected place, constructs a whitish silken cocoon within which, 
in the course of a few days, it may change to pupa, or it may remain 
in the larval condition until the following spring, as already ex- 
plained. The pupa (fig.2,¢) is about one-half inch long, at first 
yellowish or brownish, but later becoming quite dark brown, and 
shortly before emergence of the moth assuming a distinct bronze 
color. The pupal stage varies much in length, but on the average 
about 20 days elapse from the spinning of the cocoon until the emer- 
gence of the month. After emergence the moths, in the course of a 
few days, begin egg laying, the entire life cycle, from egg to egg, 
requiring, on the average, some 50 days. 
TREATMENT. 
The treatment for the codling moth is limited almost entirely to 
spraying the trees with arsenicals, such as Paris green or arsenate of 
lead; the latter is now principally used. In the East the poison is 
usually combined with a fungicide. In some sections banding of 
trees is also employed and under special conditions is a valuable 
adjunct to spraying. From two to five spray applications are given, 
according to the section of country. 
First application.—Of all treatments, the first is much the most 
important; this is given as soon as the blossoms have fallen and has 
31336°—Bull. 492—12 2 
