Published on 11/03/04

Powder post beetles can destroy hardwood.

By Sharon Omahen
University of Georgia

Many homeowners dream of installing hardwood flooring. But they don't dream of repairing the damage caused by tiny beetles that can stow away in the wood.

"Each year I get about 10 calls from people who have powder post beetles in their hardwood floors, picture frames, bannisters or molding," said Dan Suiter, an entomologist with the University of Georgia College of Agricultural and Environmental Sciences.

"They've figured out it's insect damage," Suiter said. "And they call me to find out which insect and what to do about it."

Scientists i.d. hundreds each year

Each year UGA entomologists identify hundreds of insect samples forwarded to them by county extension agents across the state.

One culprit is the powder-post beetle, an insect that typically emerges from wood as an adult in winter months. The homeowner may have just spotted the beetle, but Suiter said it had actually been living inside the wood for a year or more.

The adult beetle lays its eggs on unfinished wood. The larva borrows into the wood, molts several times, becomes a pupa and emerges a year or so later as an adult.

"To emerge, the adult has to chew itself out of the wood," Suiter said. "When it does, it defaces the wood because it now has small holes in it. And the homeowner begins to notice the holes and a powder residue."

The holes are typically 1/16 to 1/32 of an inch in diameter, and the powder resembles baby powder.

Either remedy's costly

The beetles enter the wood shortly after it's processed and before a finish has been applied. "Wood finish actually deters the female beetle from laying eggs," Suiter said.

There are several groups of powder-post beetles, but the lyctid powder-post beetle infests only hardwoods.

"The lyctid beetle causes the most problems to people because its food source is hardwood," he said. "And unlike most insects, the life cycle of these beetles is measured in years because wood isn't a good source of nutrition. The beetles compensate for the poor nutritional quality by having lengthy life cycles."

If these beetles are feeding on your hardwood floors, Suiter said, getting rid of them can be costly.

"The most economically feasible remedy is to replace the wood," he said. "Check with the hardwood supplier to be sure the purchase carries wood replacement insurance, which may be needed in the unlikely event of a lyctid infestation."

If you plan to install a hardwood floor, Suiter recommends making sure the installer is insured against powder-post beetle infestations.

The second remedy is to fumigate the beetles.

"Fumigating can be incredibly expensive, too," Suiter said. "I'm not sure which one is more expensive, fumigating or replacing the floor. I don't know how common this beetle problem is, but if it happens to you it's going to put you in a big, big bind."

They love antiques, too

Apparently, the beetles aren’t just partial to hardwood floors. Suiter recently identified them for an antique shop owner in Blue Ridge, Ga.

"We have a haven of antique shops here. And one of the shop owners called me about small holes appearing in his carved bears," said Eddie Ayers, the UGA Extension Service county agent in Fannin County.

"Dr. Suiter verified the beetles and told us how to treat them," Ayers said. "Left untreated, they could have entered the wooden buildings in this area, caused damage to other shop owners and damaged the antique seller's business reputation."

Ayers said the shop owner shared the beetle discovery with the area's downtown association, other antique vendors and the company who sold him the antiques.

The store owner was elated to have it handled before the beetles made their way into his building.

"Identifying the problem quickly prevented him from selling defective woodwork, which would have affected his sales down the road," said Ayers.

Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.