I sprayed my Douglas Fir log home with a borate solution a few years before I finally brushed on a tinted finish recommended by a lumber yard that sells log home finishes and other products. I still have beetles in my east-facing shady wall.
I noticed when I recently sprayed a wasp nest that the spray soaked into the logs. If I want to retreat with borate, do I really have to strip the finish if the borate solution soaks through it? Thanks