POWDER POST BEETLE (Lyctus-brunneus)

  • Adult powderpost beetles are small, brownish or black and are less than 5/16 of an inch long.
  • These beetles’ body shape ranges from long and thin to oval.
  • When viewed from above, the head is not visible since it is hidden under the first segment of the insect’s body.
  • The larval stage is small, lightly colored and grub-like in appearance.
  • Powderpost beetles are usually recognized by the presence of wood frass that is produced by the larvae as they feed on wood.
  • The Powderpost beetles that are the most damaging as are the furniture beetle.
  • The powderpost beetles will infest both hardwoods and softwoods, however, the adults do not feed on the wood.
  • It is the larval stage that does the damage as they feed and develop in the infested wood.
  • They prefer seasoned, older wood located in cooler areas of the home (crawl space and basement) with moisture content of more than 14 percent.
  • Powderpost beetles most frequently infest structural components (beams, sill plates, joists, subflooring and plywood) of the home that are softwoods such as pine, fir and spruce.
  • Powderpost beetles will also infest hardwood furniture and flooring.
  • Powderpost beetles prefer to lay their eggs in cracks; in old beetle exit holes; or under wood splinters.
  • Upon hatching, the larvae bore into the wood, begin to feed and finally become adult beetles that bore round exit holes about 1/8 inch in diameter.
  • The complete life cycle from egg to adult normally takes about one to three years.
  • Adult females can fly, but usually lay their eggs in the same wood they exited from.