Powderpost beetle

True Powderpost beetles are a group of woodboring beetles in the insect subfamily Lyctidae and the false powderpost beetles, the family Bostrichidae. These, and other woodboring beetles Anobiidae (anobiid, Anobium punctatum (common furniture beetles), and deathwatch beetles), all fall in the superfamily Bostrichoidea. The damage caused by the family Cerambicidae (the most common is the Old House Borer) is often confused with that of powder post beetles. However the damage is often very old, and of no consequence.

Name

The term "powderpost" comes from the fact that the larvae of these beetles feed on wood and, given enough time, can reduce it to a mass of fine powder. They are therefore considered pests. The family Anobiidae is the only one capable of digesting cellulose, the primary ingredient of wood, and all other species excrete the wood without digesting it.

Life cycle

Powderpost beetles spend months or years inside the wood in the larval stage. Their presence is only apparent when they emerge from the wood as adults, leaving pin hole openings, often called "shot holes" behind and piles of powdery frass below. Shot holes normally range in diameter from 1/32 inch, (0.8 mm) to 1/8 inch (3 mm), depending on the species of beetle. If wood conditions are right, female beetles may lay their eggs and reinfest the wood, continuing the cycle for generations. Heavily-infested wood becomes riddled with holes and rooms or basements packed with a dusty frass — wood that has passed through the digestive tract of the beetles. The larvae feed mainly upon starch in the wood. They leave holes in your wood.

Target materials

Depending on the species, Powderpost beetles can feed upon certain hardwoods or softwoods. Some hardwoods are naturally immune, if they have low starch content, or if the pore (vessel) diameters are too small for the female beetle's ovipositor which prevents her from inserting eggs into the substrate.

Wood preservatives can be used to treat the wood and prevent beetle infestation. The most common treatment uses boron.

Items that can be infested by powderpost beetles include any wooden tools or tool handles, frames, furniture, gun stocks, books, toys, bamboo, flooring, and structural timbers.

External links

* [http://www.nature.nps.gov/biology/ipm/manual/museum.htm Museum pests including powderpoke] at the National Park Service.
* [http://www.msue.msu.edu/msue/imp/mod02/01500546.html Powder post and other wood boring beetles] from Michigan State University Extension.