M333Ab Selkirk Mountains

Landscape Characteristics:

Glaciated mountains that formed in granitic, gneiss, schist, quartzite, argillite, and phyllite rocks. Volcanic ash layers occur on the soil surface over much of the area. Elevations range from 1800 to 7700 feet. Drainage density is moderate.

Climate:

Mean annual precipitation ranges from 25 to 70 inches, about 50 percent falling as snow. The soil temperature and moisture regimes are cryic and udic (frigid and xeric at lower elevations). Rain on snow events are fairly common.

Potential Vegetation:

Cedar-hemlock-pine forest/Douglas-fir forest/Western spruce-fir forest

Relationships of Dominant Map Unit Components:

Landform Geology Soil Taxa
Valleys/wetlands Alluvium/till Aquands/Vitrands/Cryands
Mountainsides/ridges Till Udivitrands/Haplocryands/Cryochrepts/Xerochrepts
Cirquelands Granitic/gneiss/schist/till Cryochrepts/Haplocryands/Cryumbrepts/Fulvicryands

Disturbance and Land Use:

The primary natural disturbances are fire, flooding, insects and disease, and mass wasting. Land use is predominantly intensive timber harvest and livestock grazing.