The eastern part of the region contains active and dormant volcanoes in the Cascades Volcanic Arc, with elevations of up to 14,411 feet (4,392 m).

The region has a moist, temperate climate, which supports an extensive and highly productive coniferous forest that is intensively managed for logging, as well as recreational use.

[1][2] Animals include black bears, deer, elk, bobcats, cougars, coyotes, skunks, raccoons, and chipmunks.

Its mild, wet climate promotes lush forests dominated by western hemlock and Coast douglas-fir, with western redcedar, bigleaf maple, red alder, vine maple, salal, rhododendron, Oregon grape, huckleberry, thimbleberry, swordfern, oxalis, hazel, and blackberry.

Soils are warmer here than in higher elevation ecoregions, and it is one of the most important timber producing areas in the Pacific Northwest.

The steep valleys trending to the west contain high and medium gradient rivers and streams that support cold water salmonids, including the threatened Chinook salmon, steelhead, and bull trout.

[1][2] The Western Cascades Montane Highlands ecoregion is characterized by steeply sloping, dissected mountains with high to medium gradient streams and glacial rock-basin lakes.

Today, the region is heavily managed for logging and recreation, and it is an important water source for lower elevation urban, suburban, and agricultural areas.

[1][2] The Cascade Crest Montane Forest ecoregion consists of an undulating plateau punctuated by volcanic buttes and cones that reach a maximum elevation of about 6,500 feet (2,000 m).

[1][2] The High Southern Cascades Montane Forest ecoregion is an undulating, glaciated, volcanic plateau punctuated by isolated buttes and cones.

The region covers 915 square miles (2,370 km2) in Southern Oregon and includes the lower elevations of Crater Lake National Park.

[1][2] The Southern Cascades ecoregion is lower in elevation and less rugged than the surrounding regions and is characterized by gently sloping mountains and broad valleys.

The region covers 1,414 square miles (3,660 km2) in Southern Oregon, in the South Umpqua and Rogue River watersheds, separated from the Western Cascades by the Calapooya Divide.