What's That In The Tree?

While leaving the Monocacy Battlefield this afternoon my wife said "what is that in that tree?"  Quickly stopping, I just couldn't tell what it was..

 

Zooming in I could see that it was a furry critter...

 

 

Too small to be a bear, and too large to be a squirrel...

It finally peeked around the trunk and I could see that it was a groundhog...

 
Not often found in trees, they do have the ability to climb to escape danger or reach food.  In a short while he scurried down the other side of the tree and disappeared.