Snow cornice Snow cornice A snow cornice or simply cornice (from the Italian cornice meaning "ledge") is an overhanging edge of snow on a ridge or the crest of a mountain and along the sides of gullies. They form by wind blowing snow over sharp terrain breaks (e.g. the crest of the mountain) where it attaches and builds out horizontally. This build-up is most common on the steeper and leeward sides of mountains. Cornices are extremely dangerous and travelling above or below them should be avoided. When a cornice "collapses", it breaks in from the cornice to the top of the peak;
Snow Mountain Wilderness a food source for the black-tailed deer. Rare native plants include Sonoma manzanita ("Arctostaphylos canescens ssp. sonomensis") on Snow Mountain East, on St John's Mountain is the endemic annual herb bentflower fiddleneck ("Amsinckia lunaris"). Other wildlife include black bear, mountain lion, spotted owl and game birds like California quail, sooty grouse and bandtailed pigeon. Activities in the wilderness include day hiking, backpacking, skiing, fishing and horseback riding. The Forest Service encourages the practice of Leave No Trace principles of outdoor travel to minimize human impact on the environment. There are of maintained trails and of unmaintained trails. Eight trailheads provide