Ambrosia Beetles Versus Powderpost Beetles

A little info on similar, but different, bugs that infest different types of wood. January 27, 2008

I have what appears to be a powder post beetle infestation in southern yellow pine lumber that I milled myself. The logs came from a tree surgeon and some have been down for some time. I have much of this lumber stickered and air drying, as I do not have a kiln. I have also used some of the lumber to build outbuildings. Because we have had very dry weather this year, the lumber is now as dry as a kiln would get it, but it is certainly not sterilized. What is the chance that this infestation is over? Short of kilning the lumber, what should I do to maintain the integrity of the buildings and remaining lumber?

Forum Responses
(Sawing and Drying Forum)
From Professor Gene Wengert, forum technical advisor:
The lyctid powderpost beetles infect hardwoods. You have another insect and until it is identified, it is hard to tell you what to do. It is a guess that the activity will stop as the wood reaches a low MC.

From the original questioner:
Thanks Gene. Maybe they are not PPB, but the holes look like pictures I have seen of PPB and there were small piles of sawdust in the stickered lumber. I have never seen what I thought could be the culprit - only their sign. Any ideas as to what the bug could be, based on the sign they leave behind?

From Professor Gene Wengert, forum technical advisor:
Is there a dark ring around some of the holes? What is the hole diameter? For positive ID, take samples of the wood to your county extension office.

From contributor J:
I also have that in my Monterey pine - little pin holes, and the buggers that leave them are little beetles. Thought they were lyctid, but I could be wrong, again. I have to make a heat chamber to cook the buggers or my wood floor will not be suitable to put in the house. I will see if the extension folks can identify it.

From Professor Gene Wengert, forum technical advisor:
It sounds like ambrosia beetles.

From the original questioner:
Some of the holes have a dark ring around them and some do not. I assumed the ones without the ring were new and the others were old. I'll see if I can find any info on the ambrosia beetle. Are they as bad as powderpost?

From Professor Gene Wengert, forum technical advisor:
Ambrosia beetles have the dark ring oftentimes. They do not like dry wood at all, so they are not as bad as PPB. Nevertheless, they can do severe damage to wetter wood. Control them by eliminating wood trash from the drying yard and by drying the wood. They may have 3 cycles per year, so removing trash wood removes their preferred breeding material. Note that some trees will get a bark beetle and even ambrosia beetles while standing if they are dead trees. Again, not a continuing problem if the wood is dry.