51 
and have found it thrnout the state. In parts of Michigan, peach- 
trees have sometimes been nearly destroyed by it, and an equally se- 
rious injury has been done by it in New York to pears. In Illinois 
we once found it at Effingham cutting off young apples-trees from 
Fig. 56. Oak Twig-pruner, Elaphidion villosum, larva. 
About 5 times natural size. 
one to two feet above the ground ; and Dr. F. W. Coding reported 
it, in 1884, as doing great damage to hickory and elm at Ancona, in 
Livingston county. In Pennsylvania, oak forests have been so in- 
fested by it that carloads of the twigs might have been collected 
from under the trees ; and in Connecticut, hickories have been so 
thoroly pruned that a barrel of twigs and branches have fallen 
from a single tree. 
The injury done by this insect is not, however, so severe as it 
looks. It may affect considerably the appearance of young trees, 
by deforming their top ; ])ut large trees are generally little harmed 
by the pruning they receive, and the littering of lawns with ampu- 
tated twigs is at most an annoyance merely. The girdled twigs and 
branches may vary in length from a few inches to several feet, but 
Dr. Fitch mentions one that was ten feet long and over an inch 
thick. Commonly, however, they are a quarter of an inch or le^s 
in diameter, and vary from two to six inches in length. Occasion- 
ally a single one will contain two larv?e, the burrows then running 
down each side of the twig. Fallen limbs, if not disposed of, may 
serve, as Chittenden has said, as breeding places for various kinds 
of injurious borers, which may come out from them to attack and 
injure living trees. 
The method of the pruner's work is such that a fallen twig is 
seen to ha\e been hollowed out centrally — a large part of its interior 
often being eaten away — and plugged with sawdust, and its larger 
end has been gnawed oft" from within, having a cut surface as smooth 
as if made by a chisel. 
The adult twig-pruner is a rather slender, dark brown beetle 
(^'^S- 57) from a half to three-quarters of an inch in length, 
sparsely co^'ered with coarse white or yellowish hairs which show 
a tendency to collect in irregular clumps or spots. The edge of the 
tip of each wing-cover is concave between two stout sharp spines 
or teeth, of which the outer is usually the larger. The female lays 
