For three to four years the larvae bore semi-randomly through timber, following and eating the starchy part of the wood grain, and grow up to 7 millimetres (0.28 in).

The adults then break through the surface, making a 1 mm to 1.5 millimetres (0.059 in) exit hole and spilling dust, the first visible signs of an infestation.

This is readily observed from infested structures, where one piece of timber may be heavily attacked but an adjacent one left virtually untouched according to whether it is made from the heartwood or the sapwood part of a tree trunk.

[4] Simple aerosol insecticide sprays will only kill the adult borer on the wing but not the burrowing larvae, which remain relatively protected inside infected timbers.

Freezing infected timber, or heating to 50 °C for a day or more, will kill beetle larvae, but offer no residual protection.