Glading - is it really harmful to the forest?

[rickhart]

The issue of clearings affects not only trees but also some other species. Some birds, for instance, require large tracts of undisturbed forests. Clearings allow "edge species" to establish and out-compete or prey upon the deep forest species. I suspect that trails are too small an area, or area-per-acre, to be a problem.

It would be nice if everyone, skier or otherwise, found this kind of thing worth discussing.