Need advice on insect extermination

I could not find anything on this subject. I picked up a couple of green logs over the summer and put them in a shed to season. I just noticed there are little mounds of sawdust all over them where the critters are cleaning out their tunnels. What is a good method of fumigating these logs?

http://www.tikicentral.com/viewtopic.php?topic=16756&forum=7&hilite=pest%20control

The above thread has links to two more on the subject. Good luck with your pest control!

bag them and freeze them for 2 weeks