Whozat hammering on our tree?

I thought a crow had flown across our back wood to my neighbor's yard when I saw the white feathers under each wing and realized it was a Pileated Woodpecker.  I picked up my camera and waited just a short time and saw it fly back onto the side of what I call our Squirrel Tree.  The hole in the tree has been home to many generations of Squirrels.  I just imagined the current young residents saying, "Whozat hammering on our tree?"  This Squirrel tree has many, many Squirrel markings up the trunk - a small marking is visible to the bottom left of the hole.