Chapter IV. 
INSECTS INJURIOUS TO THE LOCUST TREE. 
(Bobinia pseudacacia.) 
Of insects feeding upon the locust forty-one species are here re- 
corded. By far the most pernicious borer in the trunk and the most 
deadly enemy of the tree is the locust borer, the first mentioned below. 
The twigs are often swollen and disfigured by the locust twig-borer. 
We have observed the leaves to be most damaged by the Bepressaria 
caterpillar. The other insects mentioned below are more or less pecul- 
iar to the tree, and at certain times may be locally destructive. 
AFFECTING THE TRUNK. 
1. The locust borer. 
Cyllene robinice (Forster). 
Order Coleoptera ; family Cerambycid^:. 
Boring a hole one-quarter of an inch in diameter under the bark and upwards, 
deep into the wood, and ejecting the dust through the orifice in the bark, a longi- 
corn larva, which transforms to a pupa in its burrow, and late in summer appears as 
a brown beetle, striped and banded with golden yellow, and with a VV °n its wing- 
covers ; often abuudant on the flowers of the golden rod early in September, when 
they lay their eggs in crevices in the bark of the locust. 
This is by far the most destructive pest of the locust, one of the 
most beautiful and valuable of our shade trees. In New England there 
is scarcely a tree which does not show the marks of its attacks, and in 
many localities it has practically been exteriniuated. In the Western 
States it is also very destructive ; but from observations we made in 
Kentucky in 1874 the noble locust trees in that State had grown so lux- 
uriously as to apparently escape or overcome the insidious attacks of 
this borer. It occurs throughout the United States east of the Plains. 
The operations of the grub or larva may be detected by a mass of 
sawdust like castings at the mouth of its gallery. 
The beetles are abundant, feeding on the flowers of the golden rod 
(Solidago), early in September, when we have taken them in Cambridge, 
Mass., and at Providence, R. I. So wide are the deep yellow spots and 
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