I have three beautiful S-shaped 6 to 8' x 14" x 2" pieces of cherry. They were stored dry under my kids playhouse for a number of years. Dug them out today to make benches. But, Powderpost beetles have infested the edges under the bark and about an inch toward the center. 

Can I treat these to kill the beetles, then finish with a couple of coats of stain/poly. Don't laugh, but I live in a 99.9999% bug free log home (presently battling carpenter bees in the facias).