llustration: FIG. 153. SPRAYING THE ORCHARD BRINGS LUSCIOUS FRUIT
The picture in the corner at the top shows the right time to spray for
codling moth]
_Treatment._ Destroy orchard trash which may serve as a winter home.
Scrape all loose bark from the tree. Spray the tree with arsenate of
lead as soon as the flowers fall. A former method of fighting this pest
was as follows: bands of burlap four inches wide tied around the tree
furnished a hiding-place for larvae that came from windfalls or crawled
from wormy apples on the tree. The larvae caught under the bands were
killed every five or six days. We know now, however, that a thorough
spraying just after the blossoms fall kills the worms and renders the
bands unnecessary. Furthermore, spraying prevents wormy apples, while
banding does not. Follow the first spraying by a second two weeks later.
It is best to use lime-sulphur mixture or the Bordeaux mixture with
arsenate of lead for a spray. Thus one spraying serves against both
fungi and insects.
[Illustration: FIG. 154. PLUM CURCULIO
Larva, pupa, adult, and mark on the fruit. (Enlarged)]
=The Plum Curculio.= The plum curculio, sometimes called the plum
weevil, is a little creature about one fifth of an inch long. In spite
of its small size the curculio does, if neglected, great damage to our
fruit crop. It injures peaches, plums, and cherries by stinging the
fruit as soon as it is formed. The word "stinging" when applied to
insects--- and this case is no exception--means piercing the object
with the egg-layer (ovipositor) and depositing the egg. Some insects
occasionally use the ovipositor merely for defense. The curculio has an
especially interesting method of laying her egg. First she digs a hole,
in which she places the egg and pushes it well down. Then with her snout
she makes a crescent-shaped cut in the skin of the plum, around the egg.
This mark is shown in Fig. 154. As this peculiar cut is followed by a
flow of gum, you will always be able to recognize the work of the
curculio. Having finished with one plum, this industrious worker makes
her way to other plums until her eggs are all laid. The maggotlike larva
soon hatches, burrows through the fruit, and causes it to drop before
ripening. The larva then enters the ground to a depth of several inches.
There it becomes a pupa, and later, as a mature beetle, emerges and
winters in cracks and crevices.
[Illustration: FIG. 155. LEAF GALLS OF PHYLLOXERA ON CLI
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