These peculiar woodpeckers have an insatiable appetite for acorns and they make sure they do everything in their power so that their supplies never run low. They create granaries or "acorn trees" by drilling holes in dead trees, telephone poles, wooden buildings, or any other wooden thing and then they stuff the holes with their precious acorns. LOTS of acorns. Sometimes the silly woodpeckers will go after unsuitable storage units, such as when they put 485 lbs of acorns into a wooden water tank in Arizona.

Acorns are so important to California populations of woodpeckers in particular that they will nest in the fall to take advantage of the fall acorn crop - which is a very rare behavior for birds. Gotta have those acorns!