Wood-boring beetles include several families of beetles whose larvae feed on wood and wood products. Wood-boring beetles play an important ecological role by tunneling through dead and decaying wood to aid in decomposition. Some wood-boring beetles feed on living, dying, diseased, burned, damaged, or dead trees but do not attack harvested lumber. These species can cause problems when the adults emerge from lumber in new construction or are carried indoors in firewood. Other species of wood-boring beetles may infest wood before and after it is milled, finished and installed; they may also infest furniture and other wooden objects.
Wood-boring beetle adults lay eggs in the cracks and crevices of exposed wood. When these eggs hatch, larvae bore into the wood, producing tunnels as they feed and pack frass behind them. While adults who have emerged from wood may only live a few days or weeks, the destructive larvae often spend 2 to 5 years boring through wood.
Wood-boring beetles which attack harvested wood in structures can damage almost any wood product. These may include wooden pallets, crates, or shipping carts; firewood; and household wooden items such as picture frames, broom handles, bamboo and bamboo products, wicker baskets and furniture, carved wooden art objects, wooden artifacts, decorative driftwood, wooden furniture, and wood paneling. The adults of some species also bore into soft metals, plaster, and plastic.
One or two stray beetles are occasionally brought in on firewood or other wood products and may not indicate an active infestation. Since adult wood-boring beetles emerge within wood, look for round or oval exit holes that range in size from 1/32″ to 3/8″. Fine sawdust or frass (food fragments and excrement) may fall from exit holes and create small piles on the floor or surfaces below the wood. Dust or frass reappearing within one to weeks of cleanup indicates an active infestation.
There are many species in several families of wood-boring beetles. Some families, however, only infest live trees or recently harvested wood, so it is not necessary to treat for them since they will not re-infest the dead wood. These types include ambrosia beetles, round head borers, flat head borers (including metallic borers), and bark beetles. Wood-boring beetle adults and larvae are often difficult to collect, so identification begins with examination of exit holes, frass, and damage. The most common wood-infesting beetles of concern are Powderpost Beetles (of the family Lyctidae), Deathwatch Beetles (of the family Anobiidae), and False Powderpost Beetles (of the family Bostrichidae). These beetles are typically controlled in the same manner, though severe infestations should be evaluated by a professional and may require an entomologist for proper identification.