House longhorn beetle

Occasionally mis-identified as the Common Furniture Beetle, though of slimmer appearance and having a long snout. Wood-boring weevils will only attack timber that is damp and decayed, with the damage they cause being secondary to that of the fungus. There is no fixed emergence period and holes are ragged, of about 1 mm in diameter. This beetle does not require insecticidal treatment as it will die rapidly once the affected timber has dried out. Infestation of sound, dry wood is not possible.

Seldom found outside certain areas of Surrey, infestations of House Longhorn Beetle, mainly found in roof timbers, will invariably cause structural damage. In an attempt to control and isolate the spread of this beetle, where it commonly occurs, local Building Regulations call for new roof timbers to be pre-treated with an appropriate preservative.

House Longhorn Beetle exclusively attacks the sapwood of most softwoods. The emergence of adult beetles will usually occur between July and September leaving oval holes of approximately 10 mm in length and 6 mm wide. After mating the female adult beetle will lay eggs in crevices in surrounding timbers. On warm days, where large and severe infestations occur, a scraping noise may be heard; this is the sound of the larvae feeding on the timber!

Most modern buildings will not suffer from attack by this beetle as softwood timbers are immune to the Lyctus Powderpost Beetle. It will attack the sapwood of tropical and European hardwoods, particularly those with high starch content and large pores. However, as they age these timbers become less susceptible.

The original infestation will invariably have occurred prior to the timbers being introduced into the building, though will continue for some time following. Plywood and blockboard manufactured from susceptible timbers is quite commonly attacked and occasionally infestations will be found in solid hardwood block and strip floorings.

Emergence holes are circular, 1-2 mm in diameter and consequently can be misidentified as Common Furniture Beetle by the unqualified surveyor. Lyctus Powerpost Beetle is found throughout the world. This beetle has the ability of causing very severe damage. In a relatively short period of 2-4 years it can reduce the sapwood of susceptible hardwood species to powdered matter.