After-the-kiln powderpost beetle infestation

Who's responsible for a powderpost beetle infestation, two years after the wood was kiln-dried? June 27, 2000

I recently received a complaint on an ash floor we made for a customer quite some time ago.

We dried the rough stock down to 7 to 8 percent, then planed the floor to the customer's specs. The customer stored the material in his garage for a couple years. Now, after installing the floor, he notices small piles of sawdust and has determined it is powerpost beetles.

Is this possible after going through our kiln, and should we be liable for the cost of the extermination after two years?

The kiln, if heated to 130 degrees F or hotter, sterilized the wood, so the beetles came in after drying. The garage is the likely source.

Did he have other wood stored there, especially some foreign hardwood? Powderpost beetle eggs will hatch and show up roughly year later.
Gene Wengert, forum moderator

Show him your typical kiln-drying schedule, where the temperature goes above 130 degrees. There is ample literature stating that the beetle and the eggs are killed at that temperature.

From a legal standpoint, you have no problem if you followed the standard kiln schedule for ash. From a business standpoint, the person might spread bad vibes. I'd say work with him as much as you can, but you should have no financial liability.

You need to positively identify the bug. Lumber dried to 5 to 7 percent, then stored in who-knows-what conditions for a year or more after it was sold by you, I cannot imagine any liability on your part. You need to take a bug to your state university's entomology department for positive ID; this will help determine when the infestation could have occurred.