Termites as pests

Out of the 258 described (90 undescribed) termite species in Australia, only a few wood-damaging species are of concern to humans.

The five families that include the most common pest species are:

• Mastotermitidae (1 pest species - Giant Termite, Mastrotermes darwinensis)
• Kalotermitidae (several pest species of 'dry-wood termites', including the introduced Cryptotermes brevis)
• Termopsidae (1 pest species - Dampwood termite, Porotermes adamsoni)
• Rhinotermitidae (7 pest species, including Coptotermes acinaciformes)
• Termitidae (5 pest species, including Nasutitermes walkeri)

Key species

The Giant Termite (Mastotermes darwinensis) has the greatest potential for destruction. However, it is limited to the tropical areas of northern Australia. It attacks any wood in contact with the ground including shrubs and trees, as well as paper, leather, clothing and other materials. It is a large-bodied primitive species that usually forms small colonies and has no true worker caste.

The introduced West Indian Dry-wood Termite (Cryptotermes brevis) is considered to be the world's worst termite pest as it can eat even very small timber objects with few external signs of damage, can quickly take over from native termite species, can survive in quite dry conditions, and is easily transported. If it is found, it should be reported to the relevant government authority. It has been found in Brisbane and Sydney, as well as other areas on several occasions.

However the most destructive species overall in Australia is Coptotermes acinaciformes. It is distributed throughout the continent and uses tree stumps, living trees, spaces under buildings and even walls as nesting sites. From the nest site, any wooden structure within a 50-metre radius can be attacked via underground tunnels. Although they usually need contact with soil, some nests of this termite species have even been found several floors up in city buildings or on wooden boats.

A common species that nests in Sydney's coastal bushland is Nasutitermes walkeri. It forms distinctive round ball-shaped nests that are especially abundant in the years following major bushfires (as it mainly nests in stressed trees). It can also damage fences, poles and wood on the ground, but it rarely attacks buildings. This species has the largest soldiers (up to 6 mm long) of the Nasutitermes genus, with the characteristic nasute head (tapering into a long 'nose').

Identifying pest species

Termite identification is highly specialised and pest controllers need to refer any potential pest species to the appropriate experts for full identification before any eradication program is begun.

Control

Control of pest termites involves identifying the species, locating the nest and choosing appropriate eradication methods. No single method is effective against each pest species, so a combination of doing annual building inspections in termite-prone areas, using naturally resistant or treated timbers in buildings, and installing chemical and physical soil barriers around buildings is necessary to prevent further problems.

Houses near natural bushland may often have termite nests nearby but these may not contain pest species.