- Latin Name: Prionus sp.
- Latin Family Name: Cerambycidae
- Common Name: Western Pine Beetle
- Other Names: Western pine beetle, pine sawyer
Origin:
Native beetles in North America.
Biology:
These huge beetles attack primarily dead trees, and they are some of the first insects to enter a dead tree to begin the decomposition process. There are also reports of infestations in power poles, as well as the common occurrence of them in structural wood members, where their presence is due to infested lumber used in the construction. They will not re-infest structural wood members once they emerge as adults. Conifers are the woods infested, and the larval stage may easily take several years to complete, with up to 7 years possible. Once they emerge as the adult beetle they will bore through any material between them and the light they seek, including sheetrock, paneling, linoleum, or tile. Adults are attracted to lights, and may occur in or around structures due to this.
Identification:
The adult beetles may be 2 to 3 inches long, depending on the species, and the larvae may be over 4 inches long. The larvae are “round-headed” borers, and when viewed head-on they are round and elongate, tapering more narrow toward the rear. They have distinctly segmented bodies. Adult beetles are brown to dark brown or almost black, with very long antennae and strong jaws. Some species have sharp spines along the sides of the prothorax. As the larvae feed through solid wood they pack their stringy fecal matter behind them in the channels. This material is packed tightly in the wood, and often will be exposed at the surface of milled lumber as the milling cuts across these feeding channels.
Characteristics Important to Control:
No control normally will be needed, although repairs to surface damage of walls or floors will be required. In most cases only one to a few beetles will be in structural wood, and it does not warrant a fumigation. The best advice is to let the problem run its course and fix the holes that are made.
