M333Ac Northern Idaho Valleys

Landscape Characteristics:

Wide valleys, outwash plains, and terraces that formed in alluvium, glacial outwash, and lacustrine sediments. Elevations range from 1400 to 4000 feet. Drainage density is low to moderate.

Climate:

Mean annual precipitation ranges from 15 to 40 inches, about 30 percent falling as snow. The soil temperature and moisture regimes are frigid and typic xeric.

Potential Vegetation:

Cedar-hemlock-pine forest/Western ponderosa forest

Relationships of Dominant Map Unit Components:

Landform Geology Soil Taxa
Terraces/outwash plains Lacustrine sediments/outwash Xerochrepts/Haploxeralfs/Haploxerolls
Floodplains Alluvium Haploxerolls/Vitraquands/Haplaquolls/Fluvaquents

Disturbance and Land Use:

The primary natural disturbances are fire and flooding. Land use is predominantly agriculture and urban/suburban development.