What causes woodpeckers are destroying my tree?

Bark stripping and deep excavation occur where wood-boring insects or carpenter ants are already established, which means the wood is dead, decayed, or moisture-soaked. In central Indiana, blonding on an ash trunk is one of the classic field signs of emerald ash borer. Pileated excavations usually track carpenter ant galleries running from an old wound, a pruning stub, or a decay column. Sapsucker rows follow no defect at all — it is ordinary feeding behavior on a sound tree.