. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. DAMAGE TO CHESTNUT POLES BY INSECTS. 3 to 4 inches in from the exterior of the poles; this so weakens the poles that they break off close to the surface of the ground. The basal 2 feet is usually sound. Even if the damage is not serious enough to cause the poles to break off under strain, they are likely to go tlown during any storm, and thus put the wire service out of com- mission ; such damaged poles are a serious menace along the right of way of railroads. The beetle will attack poles that are perfectly sound
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. DAMAGE TO CHESTNUT POLES BY INSECTS. 3 to 4 inches in from the exterior of the poles; this so weakens the poles that they break off close to the surface of the ground. The basal 2 feet is usually sound. Even if the damage is not serious enough to cause the poles to break off under strain, they are likely to go tlown during any storm, and thus put the wire service out of com- mission ; such damaged poles are a serious menace along the right of way of railroads. The beetle will attack poles that are perfectly sound, but evidently prefers to work wdiere the wood shows signs of incipient decay; it will not work in wood that is ''sobby" (wet rot), or in very "doty" (punky) wood. It has not yet been determined just how soon the borers usually enter the poles after they have been set in the ground. However, poles that had been standing only four or five years contained larvse and adults of this borer in the heartwood, and poles that had been set in the ground for only two years contained young larvae in the outer layers of the wood. Poles that appear sound on the exterior may have the entire basal interior riddled, and the work of the borers is not noticed until the poles break off. If merely iso- lated poles are injured, the poles that are broken off are held up by the wires and can be detected by the fact that they lean over, but if several adjacent poles are affected, especially where there is any unusual strain, that portion of the line is very likely to go down. The presence of the borers in injurious numbers can l)e de- termined only by removing the earth from about the base of the pole; -the exit holes of the borer are found near the line of contact with the soil. Often large, coarse borings of wood fiber project from the exit holes. Sometimes old dead parent adults are found on the exterior of the poles underground. During August the young adults may be found in shallow
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