Subterranean termites normally damage the interior of wood structures. Shelter tubes are the most common sign of their presence. Other signs include structural weakness of wood members, shed wings or warmers, soil in cracks or crevices, and dark or blister-like areas on wood.

The major characteristics of infested soft wood when it is broken open are that damage is normally greatest in the softer spring wood and that gallery walls and inner surfaces of shelter tubes have a pale, spotted appearance like dried oatmeal. The galleries often contain a mixture of soil and digested wood. Termites usually enter houses through wood in contact with the soil or by building shelter tubes on foundation walls, piers, chimneys, plumbing, weeds and gardens.

Although they normally maintain contact with the soil, subterranean termites can survive when they are isolated from the soil if they have a continuing source of moisture. Heavy damage by subterranean termites (except Formosans) does not normally occur during the first five to 10 years of a building's life, although their attack may start as soon as it is built.

Subterranean termites can be controlled most effectively by the use of chemicals in the soil and foundation area of the house, by breaking wood-soil contact, and by eliminating excess moisture in the house. When applied properly, these chemicals will prevent or control termite attack for at least 25 years.