Tetropium velutinum (Cerambycidae)
the western larch borer
Adults:
|
Elongate, velvety brown beetles about 12 mm long. Eyes divided in two parts. Long antennae give this family of beetles the "longhorned" beetle common name. |
Larvae:
White, elongate, elyptical in cross-section. Narrow thorax. Small thoracic legs present. Segments distinct. Body not strongly tapered.Damage:
Common in fire killed timber, cold deck piles left over summer, drought weakened and insect defoliated trees. Larva is a shallow sapwood borer and bark miner. The larva do enter the wood to pupate. The holes left in the wood are elliptical in cross-section and adult exist holes are circular.Principal Hosts:
Western larch, Douglas-fir and western hemlock are the preferred hosts. Species
of Abies, Pinus and Picea are recorded hosts.
Economic Importance:
During the drought of the 1930's this species caused extensive deterioration
of larch stands in N.W. Washington.
References and Links:
FC: 294.
