Section M332E Flathead Valley
Geomorphology. There are glaciated mountains, glacial moraines, large glacial troughs, and glacial and lacustrine basins. Elevation ranges from 2,000 to 7,000 ft (610 to 2,135 m). This Section is within the Northern Rocky Mountains physiographic province.
Lithology and Stratigraphy. Types include predominantly Precambrian metasedimentary rocks of the Belt supergroup, with glacial deposits and valley fill.
Soil Taxa. Soils include frigid and cryic Ochrepts, Boralfs, Orthents, Udands, and Cryands in the mountains, with Borolls, Ochrepts, Xerolls, Psamments, and Fluvents in the basins and valleys. These soils are generally moderately deep to deep with loamy to sandy textures. Most of the soils have been strongly influenced by volcanic ash deposits, which make them very productive.
Potential Natural Vegetation. Kuchler mapped vegetation as Douglas-fir forest and western ponderosa forest. Principal tree species include Douglas-fir, ponderosa pine, hemlock, cedar, and grand fir.
Fauna. Birds are typical moist northern Rocky Mountain species, including Vaux's swift, calliope hummingbird, pileated woodpecker, gray jay, red-eyed vireo, and Townsend's warbler. Other species of note are common and Barrow's goldeneyes, harlequin duck, osprey, boreal owl, barred owl, Cordilleran flycatcher, American dipper, and varied and Swainson's thrush. Species nearing the edge of their range are the boreal and chestnut-backed chickadees, and northern water thrush. The endangerd bald eagle is a relatively common breeder in this Section. Typical herbivores and carnivores include white-tailed deer, mule deer, elk, moose, black bear, bobcat, and cougar. The woodland caribou were historically present within this Section but are now absent. Smaller common herbivores include the snowshoe hare and northern flying squirrel. Rare mammals include the grizzly bear, gray wolf, lynx, fisher, wolverine, northern bog lemming, and the Coeur d' Alene salamander. Herpetofauna typical of this Section are the spotted frog, wood frog, Pacific treefrog, western toad, and long-toed salamander.
Climate. Precipitation ranges from 18 to over 100 in (460 to over 2,540 mm); most of the precipitation in fall, winter, and spring is snow; summers tend to be dry. Climate is cool temperate with some maritime influence. Temperature averages 36 to 45 F (2 to 7 C). While maritime influences are present and winters are relatively mild, outbreaks of arctic air occur frequently in winter. The growing season ranges from 45 to 120 days.
Surface Water Characteristics. Several major rivers, including the Yaak and Kootenai, and many perennial streams with dendritic drainage patterns dominate the area. There are many lakes, including Lake Koocanusa and Flathead Lake, as well as bogs, and wetlands.
Disturbance Regimes. Fire, insects, and disease are the principal natural sources of disturbance.
Land Use. Timber harvest, wildlife habitat, and recreation are important land uses. Livestock grazing and farming occur in some valley areas.
