Subterranean termites live in the soil alongside the wood they are consuming. They build earthen tunnels over concrete or brick to reach upward toward wood. They are considered one of the most destructive wood-feeding insects. Successful termite control usually consists of utilizing bait systems and liquid insecticides. The homeowner also must focus on prevention to discourage the subterranean termites from invading the wood of houses and other buildings. Barriers of chemically treated soil around homes and buildings can prevent termite infestation for up to two years. Once an infestation occurs, prompt treatment of the soil is paramount.
Place stakes of termite control bait around the areas of subterranean termite activity. Termite control bait is sold under many brands. The bait is normally housed in plastic spikes with tiny holes. The termites enter the holes to consume a toxic bait substance mixed in wood cellulose. The bait works as a slow toxin that kills the termites over two weeks to one month. The termites bring the bait back to the colony where it is readily consumed by other termites. The bait sticks to the termites and is groomed off by members of the colony. The bait renders termites sterile, then kills them. Follow the directions on the bait for application instructions.
Break away all shelter tubes on concrete, wood, brick and soil. These tubes offer protection to the termites. Break them away using a shovel, hand trowel or wire bristle brush.
Drench the soil where the termites reside, using either imidacloprid or fipronil insecticides. Follow the directions on the label for application and mixing ratios. Apply with a backpack sprayer or a handheld garden pump sprayer.
Drill into infested wood areas with a 3- to 4-inch drill bit that is 1/2 inch in diameter or larger. Spray foam-based fipronil into the wood. Follow the directions on the fipronil label for application instructions.