Drywood Termite

Drywood termites, most commonly represented in North America by species in the genus Incisitermes, are termites that establish their entire colony inside a single piece of sound, dry wood rather than maintaining contact with soil moisture as subterranean termites do. This lifestyle allows drywood termites to infest structural lumber, furniture, and dead wood in dry conditions, and it distinguishes them ecologically and behaviorally from ground-nesting subterranean species.

Because colonies are self-contained within wood and relatively small compared to subterranean termite colonies, drywood termite infestations are often first noticed through small kick-out holes in wood surfaces and characteristic piles of hard, six-sided fecal pellets that the insects push out of their galleries.

• Workers and soldiers are pale tan to light brown, roughly 0.4 to 0.5 inch (10-13 mm) long, without wings
• Soldiers have a large, dark, rectangular head with pronounced mandibles used to block gallery entrances against intruders
• Winged reproductives (swarmers) are brown with two pairs of equal-length, smoky or clear wings
• Straight, bead-like antennae and a broad-waisted body distinguish termites from ants
• A key sign of drywood termites is the presence of small, hard, ridged, six-sided fecal pellets (frass) that accumulate below tiny kick-out holes in infested wood, unlike the mud tubes built by subterranean termites
• No mud shelter tubes are built, since this group does not require soil contact

Drywood termites live inside sound, dry wood such as structural framing, furniture, dead tree limbs, and utility poles, without needing a connection to soil moisture. They are found primarily in warm coastal and southern regions, including the southern United States, California, Hawaii, and many tropical and subtropical areas worldwide, since their survival depends on climates warm enough that wood does not freeze. Colonies remain hidden within wood year-round, with swarming flights of new reproductives typically occurring during warm months, often in the evening or at dusk.

This group feeds directly on the wood in which it lives, digesting cellulose with the aid of symbiotic gut microorganisms, and does not forage outside the wood or maintain the extensive tunnel networks typical of subterranean termites. A single piece of infested wood can house a self-sufficient colony for years, with the insects excavating galleries across the grain and periodically pushing pellet-shaped frass out through small kick-out holes to keep their galleries clean. Because they do not need soil contact, drywood termites can infest elevated structural wood, furniture, and picture frames far from the ground. In natural settings, drywood termites contribute to the breakdown of dead wood and standing dead trees, functioning as decomposers, even though their presence in structural or worked wood is considered a nuisance pest issue.

A mated pair of winged reproductives lands after a swarming flight, sheds its wings, and bores into a small crack or crevice in dry wood to start a new colony. The pair raises an initial brood of nymphs that develop gradually through incomplete metamorphosis into workers, soldiers, or future reproductives as the colony's needs dictate. Because the colony is entirely enclosed within the wood and colonies tend to be smaller than those of subterranean termites, growth is slower, often taking several years before a colony is mature enough to produce its own winged swarmers. Established colonies can persist for many years within a single timber, periodically releasing swarms during suitable warm-season conditions to found new colonies elsewhere.