Curtin, OR – Shasta, CA
Location: This physically and biologically diverse ecoregion occurs between the Cascades and the Coast Range in northwestern California and southwestern Oregon.
Climate: The ecoregion has a mild, mid-latitude Mediterranean climate, marked by warm summers with a lengthy summer drought period, and mild winters. The mean annual temperature ranges from approximately 5°C at higher elevations to 14°C in valleys and in southern parts of the region. The frost- free period ranges from 90 days at high elevations to 240 days or more in lower, warmer areas. The mean annual precipitation is 1,438 mm, ranging from about 500 mm in low dry areas to over 3,000 mm on the wetter high mountains.
Vegetation: The region supports a vegetal mix of northern Californian and Pacific Northwest conifers and hardwoods. Mixed conifer forests feature Douglas fir, white fir, incense cedar, tanoak, Jeffrey pine, Shasta red fir, sugar pine, ponderosa pine, chinkapin, canyon live oak, and, in some lower areas, chaparral and western juniper. Oregon oak woodlands consist of Oregon white oak, madrone, California black oak, ponderosa pine, and grasslands.
Hydrology: There is a high density of moderate to high-gradient streams and rivers. Rivers are often deeply incised in canyons; most flow westward. Major rivers include the Umpqua, Rogue, Illinois, Klamath, Trinity, and Eel. Some glacial lakes are found at high elevations in the California portion of the region.
Terrain: Landforms are rugged, highly dissected and deeply dissected mountainous terrain with steep slopes. Along with the folded mountains, foothills, terraces, and floodplains also occur. Elevations range from about 120 m to over 2,600 masl. The region contains diverse and complex geology and soils. Paleozoic and Mesozoic marine sandstones and shales, granodiorite, gabbro, and other intrusive rocks, and volcanic rocks occur. Ultramafic parent material and soils with scattered areas of serpentinitic soils occur and influence vegetation patterns in some areas. Inceptisols and Alfisols are common, with mesic and frigid soil temperature regimes and xeric and some udic moisture regimes
Wildlife: Black bear, Roosevelt elk, black-tailed deer, cougar, bobcat, coyote, river otter, beaver, California ground squirrel, peregrine falcon, osprey, red-tailed hawk, northern spotted owl, California quail, anadromous fish, numerous reptiles, various salamanders and other amphibians are to be found.
Land Use/Human Activities: Forestry, recreation and tourism, some ranching and grazing predominant, along with hay, pasture, and some truck farming in valleys. A few mining areas exist. There are also large areas of national forest land or other public land. Larger cities and towns include Roseburg, Grants Pass, Medford, Ashland, Yreka, and Weaverville.
Commission for Environmental Cooperation; North American Terrestrial Ecoregions—Level III; April 2011.
Photos taken in October 2013 along highways-
Just Another Nature Enthusiast Photography by Jane Wilson is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.