I have some timber from an old barn that has some evidence of bugs. I am recutting it into a small barn frame. What is a good treatment of the wood to prevent them from coming back? Thanks.

If your timbers are contained in a compact pile, you can tent them or tarp them securely and fog with an insecticide[you may want to contact an exterminator]. If you have room to spread them out, you could spray them on all sides with a borate/ water solution, but this may not be effective on insects/eggs deep within the timbers.