Some timber harvest also occurs. Compiled by Northern Region. This area comprises steep dissected mountains, some with sharp crests and narrow valleys. This Section is within the Northern Rocky Mountains physiographic province. Lithology and Stratigraphy.
Predominant rocks are Precambrian metasedimentary of the Belt supergroup.
There are frigid and cryic Ochrepts and Boralfs, with some Udands and Cryands on areas where significant amounts of volcanic ash have been deposited. In general, many of the soils have been strongly influenced by deposits of volcanic ash which have made them productive. These soils are generally shallow to moderately deep with loamy to sandy textures. Potential Natural Vegetation. Common species include western redcedar, western hemlock, western white pine, Douglas-fir, and ponderosa pine.