THE PEACH TWIG-BORER. 
(Anarsia lineatella Zell.) 
INTRODUCTION. 
This insect is of European origin, but has been known to occur in 
the United States since 1860. It has-been very injurious at times to 
peach trees in the peach-growing sections of the East, notably in 
Maryland, Delaware, and Virginia, also in New Jersey and New York, 
and more recently in West Virginia. In California and Oregon, and 
elsewhere on the Pacific slope, its injuries have taken a wider range, 
including damage to the apricot, almond, nectarine, prune, pear, and 
perhaps other fruit trees in addition to the peach. 
In California it is listed as one of the three or four worst insect 
pests occurring in the State. Im Washington as many as one hundred 
larvee, or instances of damage to as many twigs, have been counted on a 
single tree. In Oregon this insect is stated to be next to the peach-tree 
. borer in the amount of damage it occasions, particularly in the Wil- 
lamette Valley. In western Colorado it is very destructive to peach, 
plum, apricot, and almond. 
The injury occasioned by this insect is limited almost exclusively to 
the work of the hibernating larvie during the latter part of April and 
first of May, when they bore into the shoots of new leaves, killing the 
growing terminals and preventing the development of the branch, 
although sometimes a whorl of living leaves may remain at the base. 
Much of the new growth of the tree is often killed, in many instances 
the branches remaining with scarcely a bud or shoot which has not 
been thus destroyed. This necessarily results in greatly checking the 
vigor and fruiting capacity of the tree, and causes an irregular and 
knotty growth. 
The summer broods of larvee feed beneath the bark or in the fruit 
stems, occasionally, when nearly full grown, boring into the fruit; but 
such damage is not ordinarily noticed and is slight as compared with 
the injury occasioned by the first or hibernating brood of larvee. 
RECENT STUDIES OF THE INSECT. 
Up to comparatively recent years the knowledge of this insect has 
been practically confined to its injury to peach twigs, either in terminals 
before the trees leaf out in the spring, a rare form of attack, or in the 
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