Termites or "white ants" (Isoptera) work from a nest or colony in the ground. Most effective control is by preventing them from entering any timber structure. Where this cannot he done, resistant timbers must be used or chemical treatment carried out.

Three main types of individuals or castes in a colony arc workers and soldiers, which are sterile, and sexual males and females.

Workers constitute most of the colony, carry on the construction of the nest, forage for food and travel to and from the nest in the ground in a continuous stream ; they cannot exist without communication with the nest. Soldiers protect the nest from invaders.

Occasionally, in warm, humid weather, winged males and females leave the nest in thousands. After a short flight they alight and cast off their wings. The sexes pair and form a new nest in a chamber in the ground adjacent to timber or an old stump ; a few survive to found new colonies, of which they become king and queen. Eggs are laid and new generations of worker termites are produced. The queen, which may live and continue to lay eggs for many years, is the central figure in the nest.

Termite galleries may he followed back through the structure of the building. along flooring hoards, into joists and bearers, and down a communication gallery, in the form of mud-covered runway built over the foundations. This leads to the ground and to a passage beneath the surface to the nest, which may be nearby or up
to 100 yards away. Several such mud-covered communication galleries may occur in the one infested building.