Wood Signs of Insect Infestation

Many species of insects live in and feed on wood. Common wood pests include boring insects, beetles and ants. Preventing significant damage in wood depends largely upon detecting insects early and recognizing the signs of infestation before extensive damage has occurred.

Wood infested with boring insects such as anobiid powderpost beetles often has emergence holes visible on the surface of the wood. Powderpost beetles are often found in sills, beams, joints and plywood. Emergence holes are typically 1/6 to 1/8 inches in diameter and are round. These pests leave numerous emergence holes scattered across infested wood. Insect excrement may be visible in emergence holes and tunnels in wood infested with anobiid powderpost beetles. Anobidd beetles are true beetles.

If you find small piles of fine sawdust in areas of your home, you may be infested with carpenter ants. Carpenter ants are brown or black in color and often have wings, but can be wingless. Seeing winged ants inside or outside your home all year round is a sign of heavy infestation. Carpenter ants make their home in decayed or damaged wood, but may invade structures such as houses or barns. Prolonged infestations of carpenter ants can cause serious damage to wood structures. Sawdust piled in corners of closets, crawl spaces or basements is a common symptom of carpenter ant infestation. Homeowners may hear carpenter ants inside walls, which sound like rustling noises.

Frass is insect excrement, which is typically brown or green in color and has a powdery look but a gritty feel to it. Insects such as the longhorned wood-boring beetle and powderpost beetles often leave frass at the entrance of emergence holes and in tunnels throughout the wood. Some insects, such as the longhorned wood-boring beetle, produce large volumes of frass which is tightly packed throughout tunnels in infested wood.

Many insect infestations occur when wood is brought into the home, in paneling, fire wood or flooring. Inspect all wood carefully for signs of insect infestations before bringing it inside your home. Many boring insects will not infest wood that has been varnished or painted. Applying finishes to your wood may help reduce infestation. Keep your shrubs trimmed around the outside of your home. Remove all tree stumps or trees that are dead and remove broken branches. Store firewood away from your home, bringing it inside just before burning it, to reduce infestation of insects such as carpenter ants.