My son and I spent the weekend on the Colorado Trail. Everyplace we looked, the bottom 6 feet or so of aspen trees were "damaged." A lot of it is old and I suspect it is natural.

This area has a LOT of elk. The height of the damage is probably about the depth of the snow in the winter. Notice how all the aspen on the other side of the clearing are also "damaged." There was some fresh bear scratch on the trees in the area, but I hate to think this was all done by bears.

Here is what my google-foo turned up:

Colorado State University list of Aspen Issues - including elk damage

Page showing small mammal damage

More elk damange

My guess is elk damage.

A lot of this damage is done by voles and mice burrowing beneath the snow surface. They eat the aspen bark, especially the bark that hasn't been damaged (eaten) in earlier years. At times, porcupines will add their touch but that is above the mean snow surface and rabbits (snowshoe hares) can get in their licks as well. This is pretty typical of most aspen stands in areas with a residual winter snow pack and the damage is largely superficial. There are a few aspen stands in the mountains here in SE Arizona where there is seldom any major kind of winter snow pack; the damage is a lot less evident down this way because the voles and mice need the snow cover for security. I would rather see this sort of thing than to see the initials some twit carved in aspen bark in an idle moment.

Thanks. I think there is a mixture of all the types of damage looking at the pictures closely.

I had to google voles. Had no idea they existed.

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