Characteristics of structures attacked by the wood-infesting beetle, <i>Hemicoelus gibbicollis</i> (Coleoptera: Anobiidae)

Abstract

The anobiid, Hemicoelus gibbicollis (LeConte ), is the most serious structure-infesting beetle along the Pacific Coast. This species attacks damp timbers (13-19% moisture content) in crawl spaces. basements, and outbuildings. In structures monitored for anobiids, Douglas- fir. Pseudotsuga menziesii (Mirbel), was the most abundant and readily attacked wood species, but other timbers used in building construction were also infested. Sapwood is more seriously infested than heartwood, and wood of any age can be attacked. Sill plates, rim joists, and headers adjacent to concrete foundations are among the most seriously damaged timbers. Infested buildings ranged from 8 to 122 years old, x-bar = 63.2. Infestations persist for many years. New, air-tight houses built with an abundance of sapwood in construction timbers may be at risk of beetle attack unless moisture levels are kept at a minimum.