In this close up, you can really see what the bear was after; the sweet cambium layer under the bark. Often the trees will be completely girdled, thereby killing the trees and earning the wrath of the timbermen.

Another possibility of what you have seen Daryl, is where bears have torn the bark and old wood from trees in search of beetles and larvae. This is often seen in old partially rotten trees and dead snags. I know where there are many trees like this, and may possibly post some photos of this at another time. I have recently taken the leap, and have ordered a digital camera. When I get it, and figure out how to use the new fangled gadget, I won't have to wait to get film developed before posting pictures.