I used to have a Jack Russel that did that sort of thing in all kinds of trees, thought he was a squirrel I guessOnce years ago in a local popular animal TV program i saw a dog just tearing thru spruce trees some 12 - 16 feet above the ground.
Sadly this old VHS footage have not surfaced on the internet.
Not the right one but here is one danish tree dog ( it have two favorite trees for lookout )