Old house borer and longhorned beetle damage may be found in the inspection of structural wood in crawlspaces, basements, or attics. Emergence holes of these beetles are oval and about 3/8 inch long. They may be empty, be plugged with fibrous pieces of wood, or contain wood powder (frass).
Development. Females lay eggs in crevices in the wood surface. Eggs hatch in about 10 days and the first stage larvae bore immediately into the wood. Larvae feed for one to three years, depending on wood moisture. Full—grown larvae tunnel to the wood surface and cut exit holes.
Frass. The frass of most longhorned beetles is fibrous; the frass of the old house borer is powdery.
Habits. Most longhorned beetles attack dead and downed trees and logs. They have a one- or two—year life cycle and do not reinfest the wood. Lumber made from wood previously infested by pine sawyers will contain the oval galleries made by the larvae. The old house borer infests only structural wood; it does not occur in the forest in dead trees or logs.