Porcupine damage to a tree

This was labeled at the via as "beaver damage" but it clearly is not.  I spent the better part of several summers wrapping lakeside trees with chicken wire to fend off the predations of beavers.  This pattern was left by a porcupine interested in consuming the bark, not felling the tree.

Porcupines prefer the young bark, leaves, and terminal twigs commonly found high up in the crown of a mature tree, but will strip bark anywhere on a tree’s trunk or branches. Like beavers, porcupines prefer to eat the nutritious inner tree bark or phloem. To get to it they have to remove the bark all the way down to the cambium layer of the tree, which is where the wood begins. If bark is stripped all the way in to the cambium then that part of the tree will die, though small wounds may eventually heal by new tissue growing from the edges of the wound. If porcupines remove the bark all the way around the trunk or a branch (girdling it), then the trunk or branch will be killed from that point up or out. This will weaken the tree and make it more vulnerable to damage from diseases, insects, and birds.

Grooved tooth marks approximately 5 mm wide are characteristic of porcupine damage. Squirrels and other small mammals will also remove tree bark, but small animals make smaller tooth marks. Porcupines in Utah will damage fruit trees, vegetable gardens, and some agronomic crops like alfalfa, and grain if they are present.

Bears will also debark trees.