You don’t usually see subterranean termites until damage has already begun, making termite control more challenging. That’s what makes them one of the most concerning structural pests we deal with in the Bay Area. Quiet, hidden, and highly destructive, subterranean termites are responsible for billions of dollars in property damage each year across the United States.
What Are Subterranean Termites?
Subterranean termites are social insects that live in large underground colonies. The most common species in Northern California is the western subterranean termite (Reticulitermes hesperus). Unlike drywood termites, subterranean termites require contact with soil moisture and travel through mud tubes to reach wood such as framing, beams, and subfloors. A mature colony can contain hundreds of thousands — even millions — of termites.
Why Subterranean Termites Are So Destructive
Subterranean termites work from hidden areas like walls and crawlspaces, making them difficult to detect early. They build protective mud tubes to maintain moisture while traveling between soil and wood. Their colonies are large and active year-round, and the damage they cause occurs from the inside out — often leaving wood looking intact while it is structurally compromised.
Signs of a Subterranean Termite Infestation
- Mud tubes — pencil-width brown tubes along foundation walls, piers, or plumbing
- Swarming termites — winged reproductives (swarmers) emerging from soil or wood, especially in spring
- Discarded wings near windows, doors, or vents after a swarm
- Hollow-sounding wood when tapped
- Soft or sagging floors in crawlspace areas
Why the Bay Area Is Especially Vulnerable
Recent environmental conditions have created ideal circumstances for termite activity in the Bay Area. Increased rainfall improves soil moisture, allowing colonies to expand. Warm spring temperatures trigger swarming behavior, while mild winters allow termites to remain active throughout the year. Many Bay Area homes also have crawlspace foundations and older wood framing that provide easy access points.
Professional Termite Control
Effective subterranean termite control requires a licensed professional. ATCO uses proven liquid treatment and baiting strategies to protect homes in Alameda County, Contra Costa County, Sonoma County, and Marin County. We provide thorough inspections, clear treatment recommendations, and follow-up monitoring to confirm that activity has been resolved. Contact ATCO to schedule a termite inspection.