Chewing Damage – To Pressure-treated Wood
Q: We have a wooded backyard, and a play house/swing set for the kids. The set was built about 3 years ago with treated lumber. We noticed the other day that something is feeding or chewing on the wood. Any idea on how to prevent more damage?
A: This looks like a combination of squirrel damage and pileated woodpecker damage.
Squirrel damage is seen on the corners of your upright post. Young squirrels are stupid and they will chew just about anything, including pressure-treated wood. On the other hand, pileated woodpecker’s will pull the wood back as they look for boring insects.
Even though the wood is pressure-treated, carpenter bees can bore holes and lay eggs in the wood
Image number three looks like a woodpecker exposed some bee chambers.
I don’t have a 100% cure for either creature, other than spraying hot pepper (click for sources) where the squirrel is chewing.