Wood-destroying insects pose a significant threat to homes and structures, causing extensive damage. These pests can weaken structural wood, damage framing, and reduce property value. Early identification of these insects and their signs is crucial for minimizing damage and avoiding costly repairs. Understanding which bugs consume or damage wood is the first step in protecting your home.
Common Wood-Eating Insects
Termites are highly destructive wood-eating insects, causing billions in property damage annually. These social insects live in colonies that can number in the millions, consuming wood. Termites typically have soft, creamy white to light brown bodies (1/4 to 1/2 inch long). Winged reproductive forms, or swarmers, have two pairs of equal-length wings and straight antennae.
Subterranean termites, the most common type, build nests underground and require moisture, constructing mud tubes to travel between nests and food sources. Drywood termites infest dry wood (attics, furniture, walls) without needing soil contact, while dampwood termites prefer moist or decaying wood.
Carpenter ants do not eat wood for nutrition; instead, they excavate wood to create nests and tunnels. These large ants are commonly black (some red), ranging from 1/4 to 1/2 inch in length, with queens up to one inch. Carpenter ants prefer to nest in damp, decaying wood, often found in areas with moisture issues (e.g., around windows, decks, roof eaves). Their excavation can lead to significant structural damage, as they create smooth, hollowed-out galleries within wooden structures.
Wood-boring beetles are a diverse group whose larvae feed on wood. These beetles vary in size and appearance; their larvae are typically yellowish-white with dark mandibles. Powderpost beetles, a common type, lay eggs in wood pores. Their larvae bore tiny holes as they feed, reducing wood to a fine, powdery frass.
These beetles often infest hardwoods (e.g., oak, maple, hickory), making furniture, flooring, and structural beams vulnerable. Other wood-boring beetles, like old house borers, primarily infest softwoods (e.g., pine), creating larger, oval-shaped exit holes and leaving coarse frass.
Signs of Infestation
Detecting wood-eating bugs early is important, though most damage occurs inside wooden structures, making early signs difficult to spot. Visible evidence includes mud tubes: narrow, pencil-sized tunnels of soil and wood particles, signaling subterranean termites. These tubes provide protected pathways for termites between their nests and wood sources. Hollow-sounding wood is another sign, indicating insects like termites or carpenter ants have tunneled through the interior, leaving only a thin outer layer.
Frass, or insect droppings, is another indicator, varying by pest. Termite frass, particularly from drywood termites, consists of tiny, pellet-shaped droppings resembling sawdust, accumulating near infested wood. Carpenter ants produce a sawdust-like frass, a mix of wood shavings, soil, and insect parts, often found in piles near their nesting sites or exit holes. Wood-boring beetles also leave frass, ranging from fine and powdery (like talcum powder) to coarse or gritty, often appearing around or beneath the small, round exit holes they create as adults emerge.
Discarded wings, especially near windows or doors, can indicate a swarming event by termites or carpenter ants, as winged reproductives shed their wings after mating. Faint rustling or tapping noises from within walls or wooden structures, particularly at night, can suggest active carpenter ant colonies.
Preventing Wood Pest Damage
Controlling moisture prevents wood-eating insect infestations, as many pests, particularly termites and carpenter ants, are attracted to damp environments. Repairing leaky pipes, ensuring proper drainage, and reducing humidity in basements and crawl spaces makes a home less inviting. Adequate ventilation in attics and crawl spaces also prevents moisture buildup. Sealing cracks and crevices in a home’s foundation, exterior walls, and utility openings eliminates entry points for these insects.
Maintaining a clear barrier between vegetation and wooden structures is beneficial; trimming shrubs and trees that brush against the house prevents pests from using them as bridges. Storing firewood at least 20 feet from the home and off the ground removes potential harborage and food sources. Regular inspections of wooden elements for early signs of infestation (e.g., small holes, weakened wood) aid in early detection and intervention.