Invertebrates
Western Drywood Termite
Incisitermes minor · also called drywood termite
A tiny pile of hard, six-sided pellets appears beneath an old wooden windowsill, the only outward sign that a western drywood termite colony has been quietly hollowing out the timber above for months, entirely self-contained and needing nothing from the soil far below.
Overview
The western drywood termite, Incisitermes minor, is a wood-feeding insect native to sound, dry wood habitat across forest and coastal California and neighbouring parts of the southwestern United States. Its complete independence from soil moisture, distinctive six-sided waste pellets, and reputation as a major Pacific coast structural pest make it one of the most economically significant insects in the region.
A colony that carries its home with it
Because this species needs nothing more than the wood it already lives inside, a colony can establish itself in a beam, a windowsill, or a piece of furniture with no connection to the ground whatsoever, often going unnoticed until its telltale pellets appear.
Status
Least Concern and abundant across California and neighbouring parts of the southwestern United States, widely regarded as a significant structural pest rather than a species of any conservation concern.
Western Drywood Termite: common questions
Why doesn't the western drywood termite need soil?
This species lives entirely inside the dry wood it feeds on and draws what little moisture it needs directly from that wood and the surrounding air, unlike subterranean termites, which must maintain regular contact with damp soil to survive, meaning a drywood termite colony can exist far above the ground with no soil connection at all.
What are the small pellets found near a drywood termite infestation?
These are the colony's faecal pellets, tiny, hard, and distinctly six-sided, pushed out of the infested wood through small openings called kick holes as the colony clears waste from its tunnels, and finding small piles of these pellets beneath wood is one of the clearest and most commonly used signs of an active infestation.
Why is fumigation often needed for drywood termites?
Because this species can establish hidden colonies deep within structural timber with no external connection to soil, treatments that target the ground, such as those used against subterranean termites, are ineffective, so whole-structure fumigation, commonly called tenting, is often the most reliable way to eliminate an infestation that cannot be easily located or accessed directly.
How is the western drywood termite different from a subterranean termite?
The two differ in several key ways, including habitat, since this species lives entirely inside dry wood with no soil contact while subterranean termites must stay connected to moist soil, colony size, since drywood colonies are typically much smaller, and swarm timing, since this species commonly swarms in late summer or early autumn rather than spring.