Controlling the powderpost beetle
Living the Country Life Radio Program with Betsy Freese
Radio interview source: Donald Lewis, entomologist, Iowa State University
Usually when your house is being eaten the first thing that comes to mind is termites. However, a small group of insects called powderpost beetles may be the culprit. They're not picky about where their meal comes from, whether it's your nice furniture or a support pole in the barn. Entomologist Donald Lewis from Iowa State University says they're little reddish-brown bugs that lay eggs in open pores and cracks of wood.
"The feeding action of the beetles inside the wood turns the wood into a dust-like powder," Lewis says. "It's actually the larval stage of the beetle that is eating the wood inside the lumber, and the eating action makes it into a sawdust that is as fine as talcum powder."
Take a close look at this photo. They bore tiny holes about the size of buckshot. If you break open the wood, you'll find criss-crossing powder-filled tunnels.
True powderpost beetles will rarely devour wood that's more than five years old, and attack freshly-cut hardwoods such as oak, ash, hickory, and walnut. Fortunately, their infestations disappear on their own as the wood ages.
"One of the ways to know that this is a passing problem and not an ongoing problem is to plug those holes as they appear, just with wood putty or a wood filler," Lewis says. "You close up those holes and hope that no new ones appear. Now if new holes appear, it leads us into another possibility, and that is the case of the false powderpost beetle."
The false powderpost is a more diverse group and love to munch on lumber of all ages. However, they're mostly found in wood that's more than 10 years old. They love moist wood, like what you may store in damp basements, on dirt floors in barns, or outside on the ground. Lewis says you can control them by simply bringing the affected piece inside the house, letting it dry out completely, and keeping it dry.
For extreme infestations, a pest removal professional will chemically treat the wood surface. But this isn't done very often because the chemicals are toxic.
Learn more:
Small beetles can reduce furniture to dust: Get more useful information on powderpost beetles from Donald Lewis.
Powderpost beetles: Read this fact sheet from Ohio State University, and see illustrations of different types of powderpost beetles.
Photo: Iowa State University
