Powderpost beetle identification for pest control in ME, MA, and NH

Powderpost Beetles

The lyctid beetle ranges in size from 1/32 – 1/4 inch in length. The anobiid is between 1/32 – 3/8 inch in length and the bostrichid is about 1/8 – 1 inch. Their body is long, narrow, flat and reddish-brown to black in color. The mature larvae are off-white, up to 1/2 in length and C-shaped.

A possible sign of powderpost infestation is round exit holes in wood that is between 1/32 to 1/4 inch in diameter. Both the lyctid and the anobiid can continue to re-infest the same wood over and over until it is full of holes, while the bostrichid beetle does not re-infest the same wood. The lyctid beetle leave a very fine powder-like frass under their exit holes or on the wood. The anobiid leave a powdery frass with pellets that they pack into the tunnels they bore. The bostrichid tend to leave an accumulation of fine to coarse frass underneath the area of infestation.

The lyctid beetle prefers the sapwood of young hardwoods, that are less than 10 years old. The anobiid will infest both softwoods and hardwoods. They attack structural timbers, lumber and manufactured products, such as cabinets and furniture. The bostrichid beetle also infests both softwoods and hardwoods, but prefer it to be less than 10 years old.

After the adult female lyctid beetle chews some of the wood to ensure it has the proper starch and moisture content, she lays 15 to 50 eggs within the pores of the hardwood. After 1 to 2 weeks, the eggs hatch and the larvae tunnel into the wood for the next 9 to 12 months to create feeding tunnels. The anobiids lay 20 to 60 eggs, which will hatch in about 6 to 10 days. The larvae will feed on the wood for about 1 year, before emerging as an adult. Female bostrichids bore into wood where they insert their eggs into the pores. These eggs will hatch in about 3 weeks, then the larvae bores closer to the surface until it emerges as an adult.