What Can Spread a Lyctid Infestation?

Be cautious — Lyctid powder-post beetles are hard to get rid of, and can spread even on small chips or shavings. March 13, 2007

Question
I just attended a class on making a Windsor settee. The instructor provided seat blanks (20x52x2) that had many 1/16 inch holes on the surface; subsurface, there were channels filled with dust. Because I interpreted them as evidence of Lyctid powderpost beatles, I left the piece there rather than bring it to my shop.

If I was correct and it was powderpost beatles, it raises four questions:

First: Is there any simple, on site test to determine if the infestation is active?

Second: Can tooling spread them? In this case, most of the work was with hand tools that left fairly large chips (adz, plane, brace and bit), but there was some limited sawing. Do power or hand tools leave large enough chips that any if the insect's stages could be spread to the shop where the work is done? If so, would normal clean up be enough to protect the shop?

Third: I've read that a film forming finish will keep them out of wood - will the same finish keep the adults inside the infested, finished piece and, thus, prevent their spread?

Fourth: How large a piece is necessary to present a realistic risk of infesting a new site? In my case, once isolated, would the 14 board foot seat blank be likely to provide sufficient adults to breed? How risky would it have been to take the completed piece to my shop?

Forum Responses
(Sawing and Drying Forum)
From the original questioner:
I forgot to add that the blank was poplar, and the instructor stated that it had air dried in his barn for 10 years - it had not been kilned or fumigated.



From contributor C:

A finish may keep them out but it won't keep them in. They will burrow out right through the finish. Personally, I suspect a thick poly/epoxy finish might defeat them but that's not what you want on most furniture and other nice wood products.


From the original questioner:
I'd searched the site and reviewed Dr. Wengert's articles before I posted. I found his reference to a film finish preventing the PPB’s from entering a piece, but I don't recall any mention of it keeping an adult from emerging.


From Gene Wengert, forum technical advisor:
The Lyctid PPB makes holes no larger than 1/16" in diameter. There is only one other common insect that makes such small holes and it likes wetter wood. The first step is always finding if you really have Lyctid PPB.

In answer to your questions:

First: Is there any simple, on-site test to determine if the infestation is active? If you see new sawdust from the holes, then you know. The problem is that sometimes it is a year or more before the eggs hatch and you see this evidence. Heat does sterilize the wood at that point in time.

Second: Can tooling spread them? Do power or hand tools leave large enough chips that any if the insect's stages could be spread to the shop where the work is done? Yes indeed. If so, would normal clean up be enough to protect the shop - probably not 100%.

Third: I've read that a film forming finish will keep them out of wood - will the same finish keep the adults inside the infested, finished piece and, thus, prevent their spread? It keeps them out but does not stop them if they are in and want to get out.

Fourth: How large a piece is necessary to present a realistic risk of infesting a new site? Small pieces can indeed spread them.