Termites often swarm in warmer weather and after a rain shower to start new colonies. The swarming event can be brief, so even if you do not see flying termites, you are likely to see the discarded wings around window sills, doors, heating vents, bathtubs and sinks after a swarm takes place. Termite swarmers use their wings to move away from their original colony. Their wings break off and they pair up and find locations with a wood source where the male and female can begin a new colony. Whether you see the swarm or think there might have been one, call a professional immediately.

Foraging worker termites, the ones that eat wood to feed the rest of the colony, must stay in moist conditions and away from natural enemies like ants. To get across barriers between the soil and the wood above, termites construct small meandering mud tubes from moist soil and excrement. The tubes are about the diameter of a pencil, though they can become wider. Tubes can be seen on foundation walls or inside walls, on plumbing pipes and spanning crawl spaces between the ground and the subfloor. These termite highways are a sure sign termites are or have been in the home.

Termites eat wood from the inside out along the grain, so damage often isn’t visible until it becomes significant. Termite inspectors often will tap to listen for hollow-sounding wall studs, baseboards and floors. If the wood gives way, it may reveal a hollowed-out honeycomb pattern. The wood also will include some mud similar to mud tubes, plus live termites.

Formosan termites are an especially robust, destructive species with large colonies. Walls of infested buildings may contain carton nests that hold enough moisture to allow the colony to live entirely above ground, sometimes causing bulging walls.

When building or remodeling in your home, keep an eye out for soft-bodied, light-colored insects about the size of a grain of rice. Termites avoid light, so they are seldom visible in open areas.