There are several beetle species in the US that see females deposit their eggs in cracks and crevices on the surface of wood. Once the eggs hatch, the emerging larvae plow into wood where they build internal nesting cavities. While inside, larvae rely on the nutrients in wood for sustenance, which is important for their proper development into adults. Once maturity is reached, adults emerge from exit holes on the surface of wood and proceed to mate. Most beetle species of this sort nest only in dead wood, and a large number of species infest structural wood, woodwork in homes and finished wood components of furniture. Some of the most common wood infesting beetle pests in the northeast include powderpost beetles, false powderpost beetles and old house borers.
Wood infesting beetles in the Anobiidae family are commonly referred to as “deathwatch beetles,” and this family is comprised of 260 species in the US alone. While the entire family is commonly referred to as deathwatch beetles, one of the most troublesome species in the family, Xestobium rufovillosum, is also referred to as the deathwatch beetle. Pest species in the deathwatch beetle family are most abundant in the northeast US, including the deathwatch beetle species and the aptly named eastern deathwatch beetle.
In the natural environment, deathwatch beetles infest hardwood, and indoors, this species generally infests structural hardwood, but they may also burrow into adjacent softwood. The deathwatch beetle is also known for infesting the hardwood components of furniture, especially oak. However, deathwatch beetle larvae can only consume wood that has been partially digested by fungi, so infestations only occur in wood components that have developed fungus. Because of this, deathwatch beetle infestations are usually found in wood that has been exposed to rainwater, leaky pipes or wood in poorly ventilated areas. Deathwatch beetles are also known for eating away at books, and while they are generally more of a problem in Europe than the US, they are common pests in certain parts of the northeast.
The eastern deathwatch beetle is generally more damaging to structural and finished wood sources than deathwatch beetles due to their ability to infest a wider variety of timber species, including ash, basswood, maple, beech, and elm. In homes, Eastern deathwatch beetles infest window sills, joists, beams, and flooring, and the exit holes left by emerging adults are easy to notice, as they are relatively large in size.
Have you ever found exit holes on the surface of structural or finished wood in your home?