Anobiid (family Anobiidae) infestations may be found in the inspection of joists and rafters in crawlspaces, basements, and attics. Infestations can be recognized by 1/8-inch, round holes which have frass around the outside or accumulating beneath. These beetle exit holes are usually the only sign of damage. The adult beetles live only a short time, but the larvae may live in galleries in the infested wood for up to three years.
Development. Females lay eggs on the wood surface or sometimes inside an old exit hole. The eggs hatch in about two weeks and the first—stage larvae immediately bore into the wood. The larvae feed for one to three years, depending on the wood moisture and age of the hardwood. Full grown larvae tunnel to the wood surface to pupate, then as adults, they cut emergence holes to the outside.
Frass. The frass ofanobiid beetles contains coarse, hard pellets, which feel gritty when rubbed lightly between the fingers.
Habits. These beetles infest all types of seasoned wood, both hardwoods (oak, maple) and softwoods (pine, spruce). However, softwood timbers used in house framing are the most often infested. Larvae can feed in wood with moisture content as low as 10%, eggs require about 45% relative humidity to hatch.