Termites feed mainly on wood or other materials containing cellulose. The cellulose is partially digested by protozoans living symbiotically in the intestines of the worker. Enzymes produced by the protozoans break down the cellulose into components that can be assimilated by the termites. Digested cellulose is distributed by the workers to members lacking the protozoans. Some species feed on vegetable molds that they cultivate. Other species obtain a special fluid secreted by beetles, known as termitophiles, that live as guests within the termite community.
Termite nests, called termitaries, vary widely. The nests of certain tropical species are huge moundlike structures, often 6 m (20 ft) in height. These mounds have extremely hard walls, constructed from bits of soil cemented with saliva and baked by the sun. Inside the walls are numerous chambers and galleries, interconnected by a complex network of passageways. Ventilation and drainage are provided, and heat required for hatching the eggs is obtained from the fermentation of organic matter, which is stored in the chambers serving as nurseries.
Of more than 55 species common in the United States, the majority build their nests underground. The subterranean termites are extremely destructive, because they tunnel their way to wooden structures, into which they burrow to obtain food. Given enough time, they will feed on the wood until nothing is left but a shell.
To prevent damage by termites, building foundations should be built of materials other than wood. Because cracks may develop in such foundations and provide passageways to the wooden parts of the structure, the soil should be treated first with an insecticide to discourage termitic incursions. Control is obtained also by using wood treated with creosote or some other poisonous chemical. Because most worker termites cannot live without moisture, the termitaries should be exposed to dry air.
Scientific classification: Termites make up the order Isoptera.