I have sprayed some stacks in the past. The wife was with me when we drove past this woodpile over by the big barn and she says "that woodpile was moving" so I backed up and wow, they were all over it so I hit 'em with sevin.
Been using diatomaceous earth here too. Not 100% convinced of the effectiveness though. I hit the piles as I am building them, including the wood shed. Im also kinda hoping it makes the mice and chipmunks sneeze enough to keep them out. Got a couple tubs of the stuff from tractor supply. Sca