Wood wasp

Habitat:

Softwoods. They attack unhealthy trees or newly-felled logs. Damage may be incorporated into buildings and larvae may survive to emerge as adults later, but they cannot re-infest dry timber.

Damage characteristics:

Emergence holes Large, circular, 4-7 mm in diameter.

Tunnels Precisely circular, 4-7 mm in diameter. May be exposed longitudinally during sawing or planing, giving an oval appearance which may be confused with longhorn damage. Not easily seen during handling because of densely packed bore dust.

Bore dust Coarse, densely packed, cannot be shaken out.

Insect characteristics and location:

Adults Large size, 18-35 mm, distinguishes the wood wasp from other wasps. It has a narrow body and conspicuous yellow patch behind each eye. Female has long, spine-like projection on rear of body, used for egg-laying. Dwarf adults may be produced if drying occurs during larval stage. May occasionally emerge from new timbers or firewood in buildings.

Larva Up to 30 mm, straight, cylindrical, pale cream. Dark spine on rear end. Markedly segmented, 3 pairs of legs. Occasionally found in timber.