I have these three beautiful walnut slabs that I am air drying (at about 20% mc) and have noticed small piles of fraff. Some little critter is nibbling holes in the sapwood. The fellow I purchased the slabs from recommended that I use a 1% solution of lindane and paint the sapwood with it. Where can I purchase lindane?
(Sawing and Drying Forum)
From Gene Wengert, forum technical advisor:
Lindane is a very dangerous pesticide. It lasts forever. If you put it on wood (which is illegal), the sanding dust will be very dangerous for anyone who breathes it. Further, if the wood is used for a crib and a baby teethes on the crib, big problem. You should never use lindane, let alone use it on wood. Check with your county extension agent for the rules and registration required to use it.
Note that an insecticide applied to wood only protects the outside skin of the wood. The insects are already inside and so surface treatment does little good. If you dry that wood in a kiln ASAP (130 F), your problems for future damage are ended. Sounds like you have the ambrosia beetle.
Any insects in the wood will not be affected by putting a solution of borax on the wood and treating the surface. Borax is intended for green wood, not 20% MC. As mentioned, you will not affect the insects inside the wood, so borax is a waste of time at this point, especially if you want to control the ones that are nibbling already. You cannot rewet the sapwood enough to get the borax inside the wood and not harm the wood.
Further, rewetting dry wood like you have will cause the surface to swell rapidly and can actually pull the inside apart (creating honeycomb). Therefore, one of the primary rules for drying is never rewet partially dried lumber.
As you are going to use the raw edges, I wonder if residual borax in the wood would affect the finishing. Unlike other approved insecticides used on wood when the wood is green, borax lasts for a very long time. I also wonder if borax will discolor the walnut wood.
To heat the wood to 130 F and destroy the insects would be fairly easy. Rent a trailer or a small truck with a separate cargo area, and put the wood inside. Then get a heater and heat the wood to 130. Of course, fire issues mean you will have to be very careful with the heater... maybe keep the heater outside and just push the heated air into the chamber. Think about the safety issues carefully ahead of time.