The ecoregion harbors rich biodiversity,[6] with several distinct plant communities, including temperate rain forests, moist inland forests, oak forests and savannas, high elevation forests, and alpine grasslands. Thirty conifer species inhabit the region, including seven endemic species, making the region one of the richest coniferous forest regions of the world in species diversity. The region also has several edaphic plant communities (adapted to specific soil types), notably those of the region's serpentine outcrops.
The Oak Savanna Foothills ecoregion consists of moderately sloping mountain foothills bordering the Rogue and Illinois river valleys and sharing their Mediterranean climate. Elevation varies from 1,400to4,000feet (427to1,219m). The driest area, east of Medford, is dominated by Oregon white oak and California black oak woodlands, grassland-savanna, ponderosa pine, and Coast Douglas-fir. The wetter foothills flanking the Illinois Valley support Coast douglas-fir, pacific madrone, and California incense-cedar. Understory species include oceanspray, Western poison-oak, snowberry, Idaho fescue, California brome, roughstalk bluegrass, and ceanothus. The region is lower and less dissected, with more oak woodland and less closed-canopied forest than the Inland Siskiyous. It covers 818 square miles (2,119km2) in Oregon.[5]
Umpqua Interior Foothills (78c)
The Umpqua Interior Foothills ecoregion is a complex of foothills and narrow valleys containing fluvial terraces and floodplains. Elevation varies from 400to2,800feet (122to853m). It is drier than the foothills of the Willamette Valley, partly because the summer Pacific high pressure system arrives earlier and remains longer than in ecoregions to the north. Summers are hot and dry, and soils have a xeric moisture regime in contrast to the udic soils of the Mid-Coastal Sedimentary ecoregion to the west. The slopes are covered by Oregon white oak woodland, Coast douglas-fir, grand fir, ponderosa pine, pacific madrone, tanoak, and chinquapin, with an understory chaparral community that includes snowberry, salal, Oregon grape, poison oak, oceanspray, and swordfern. Many areas have been converted to pastureland, vineyards, orchards, and row crops. It covers 921 square miles (2,385km2) in Oregon in the Umpqua Valley, including the city of Roseburg.[5]
Waldo rockcress is an uncommon endemic member of the serpentine soils flora of the Serpentine Siskiyous.
Serpentine Siskiyous (78d)
The Serpentine Siskiyous ecoregion consists of highly dissected mountains containing perennial, high gradient streams at an elevation of 1,500to4,300feet (457to1,311m). It is lithogically distinct from the rest of the Klamath Mountains ecoregion. Many plants have difficulty growing in its serpentine soils due to a shortage of calcium and high levels of magnesium, nickel, and chromium. As a result, vegetation is often sparse and composed of specialist species that have evolved to grow in the potentially toxic and nutrient-poor serpentine soils. It supports a mixed conifer forest of Jeffrey pine, tanoak, california incense-cedar, Coast douglas-fir, and montane chaparral composed of manzanita, ceanothus, Idaho fescue, and Lemmon needlegrass. Historic gold, nickel, chromite, copper, and mercurymining have contributed to water quality problems. The region covers 440 square miles (1,140km2) in Oregon, including portions of the Rogue River – Siskiyou National Forest and the Kalmiopsis and Wild Rogue wildernesses.[5]
The Inland Siskiyous ecoregion is higher and more mountainous than the neighboring foothill and valley ecoregions, with an elevation of 800to7,000feet (244to2,134m). It has a higher fire frequency, less annual precipitation, and longer summer droughts than the Coastal Siskiyous. Forest cover is a diverse and multi-layered mix of conifers, broadleaf evergreens, and deciduous trees and shrubs, featuring Coast douglas-fir, ponderosa pine, sugar pine, Oregon white oak, California black oak, pacific madrone, serviceberry, snowberry, Oregon grape, California fescue, and pacific poison oak. The largest of the Klamath Mountains subregions mapped so far, it covers 2,610 square miles (6,760km2) in Oregon, including public lands within the Rogue River – Siskiyou National Forest.[5]
Coastal Siskiyous (78f)
The Coastal Siskiyous ecoregion consists of highly dissected mountains with a wetter and milder maritime climate than elsewhere in the Klamath Mountains ecoregion. Elevation varies from 600to5,300feet (183to1,615m). Productive forests composed of Tanoak, Coast douglas-fir, Coast redwood, bigleaf maple, California laurel, and some Port Orford cedar and Nootka cypress cover its mountainous landscape, with chinqupin, salal, pacific rhododendron, and western swordfern; tanoak is more common than elsewhere in Oregon. Broadleaf evergreens, such as tanoak and pacific madrone, quickly colonize disturbed areas, making it difficult to regenerate conifer forest growth. Xeric soils derived from Siskiyou rock types are characteristic; udic soils which support western hemlock, Sitka spruce and Western red cedar are present but are less common than in the wetter Coast Range ecoregion to the west. The region covers 853 square miles (2,209km2) in Oregon, including portions of the Rogue River – Siskiyou National Forest and the Kalmiopsis and Wild Rogue Wilderness wildernesses.[5]
Klamath River Ridges (78g)
The Klamath River Ridges is characterized by highly dissected mountains, with a dry, continental climate. Elevation varies from 3,800to7,500feet (1,158to2,286m). Vegetation varies with slope, aspect, and elevation. Higher altitudes and north-facing slopes have Coast douglas-fir, white fir and red fir; lower elevations and south-facing slopes are covered in ponderosa pine and western juniper, species that are more drought-resistant than other vegetation types found within the region. The chaparral features Oregon grape, western fescue, snowberry, bluebunch wheatgrass, and ceanothus. The region covers 121 square miles (313km2) in Oregon near the Siskiyou Summit, including portions of the Rogue River – Siskiyou National Forest and the Cascade–Siskiyou National Monument.[5]
Border High-Siskiyous (78h)
The Border High-Siskiyous ecoregion consists of relatively high elevation mountains along the border area of Oregon and California. Elevations range from about 5,000 to 7,000 feet (1,500 to 2,100m), with a high point of 7,533 feet (2,296m) at Mount Ashland, Oregon. White fir and Red fir forests occur, with some Jeffrey pine on ultramafic rocks, and a few areas of subalpine habitats. With a large western to eastern extent, conditions are slightly drier to the east.[7]
Western Klamath Low Elevation Forests (78i)
The Western Klamath Low Elevation Forests ecoregion is at elevations generally less than 3,500 feet (1,100m). Douglas-fir and Port Orford cedar occur on lower slopes, grading into Douglas-fir and tanoak, or higher areas with canyon live oak. Red and white alder are typical along streams. Mixed oak stands occur on drier sites. The ecoregion generally is wetter and has a somewhat denser forest landscape than the drier Ecoregion 78k to the east.[7]
Western Klamath Montane Forests (78j)
The Western Klamath Montane Forests ecoregion generally is higher than Ecoregion 78i, with elevations typically ranging from 3,500 to 6,900 feet (1,100 to 2,100m). Annual temperatures are cooler than in Ecoregion 78i, and precipitation is greater. The vegetation consists mostly of Douglas-fir and white fir forests, with some red fir forests at high elevations. Ecoregion 78j lacks the serpentine geology of nearby Ecoregion 78d, and is composed mostly of Mesozoic quartz diorite, with areas of Jurassic slate, graywacke, shale, and sandstone.[7]
Eastern Klamath Low Elevation Forests (78k)
The Eastern Klamath Low Elevation Forests ecoregion is geologically and botanically diverse, and has some drier forests than ecoregion 78i to the west. Elevations generally are less than 3,500 feet (1,100m). Forest and woodland types can include areas of Douglas-fir, ponderosa pine, canyon live oak, and knobcone pine, along with chaparral of chamise, deer brush, and manzanita. Along streams, cottonwoods, white alder, and willows occur.[7]
Eastern Klamath Montane Forests (78l)
Typically at elevations greater than 4,000 feet (1,200m), the Eastern Klamath Montane Forests ecoregion includes a mosaic of forest and chaparral types. It often has more open tree canopies and understories than western Klamath regions. White fir, incense cedar, Douglas-fir, ponderosa pine, and sugar pine are dominant, with mountain dogwood in the understory. Some minor areas of Shasta fir or red fir occur at high elevations. Black and canyon live oaks mix with scattered conifers on drier sites, with understories of huckleberry oak and other chaparral species.[7]
Marble/Salmon Mountains-Trinity Alps (78m)
The Marble/Salmon Mountains-Trinity Alps ecoregion includes the Salmon Mountains, Marble Mountains, and Trinity Alps in the montane elevations from 3,500 to 7,000 feet (1,100 to 2,100m). The rugged region has steep slopes and numerous canyons and narrow mountain valleys. Granitic, metavolcanic, and metasedimentary rocks occur, including some areas of serpentinizedperidotite. The climate is colder than surrounding lower elevation ecoregions 78g, 78i, and 78k. Forests include Douglas-fir, white fir, and at high elevations, red fir.[7]
Scott Mountains (78n)
The Scott Mountains ecoregion is dominated by ultramafic rocks with Mesozoic mafic intrusions, along with some granitic rocks near the Trinity Alps and at Castle Crags. Elevations generally range from 3,000 to 7,000 feet (910 to 2,130m). Ecoregion 78n has more ultramaficrocks and less precipitation than Ecoregion 78m to the west. Vegetation includes Jeffrey pine, mixed conifer, and white fir. The ecoregion drains to the Trinity, Sacramento, Scott, and Shasta Rivers.[7]
Klamath Subalpine (78o)
The Klamath Subalpine ecoregion is higher, wetter, and colder than surrounding areas, with elevations generally greater than 6,800 feet (2,100m). Most of the region was glaciated, shown by the numerous cirques, moraines, and other glacial features. Shasta red fir, mountain hemlock, and some western white pine occur, as well as subalpine meadows with various mixes of shrubs, herbs, and grasses. Some foxtail pine occurs as well as small areas of Pacific silver fir to the north. Soils tend to be thin and rocky, across various bedrock types including granitics, gabbro, and ultramafic rocks. Soils deepen downslope.[7]
Duzel Rock (78p)
The Duzel Rock ecoregion is slightly lower in elevation with less relief than Klamath Mountain ecoregions immediately north or south, and it has more juniper and big sagebrush, along with scattered woodland. Ponderosa pine, Oregon white oak, and areas of Jeffrey pine occur. Some Douglas-fir is found at higher elevations and on northern slopes. Curl-leaf mountain mahogany is common in the western and southern parts. The geology is mostly Cambrian through Devonianmetasedimentary and minor metavolcanic rocks including metamorphosed conglomerate, sandstone, shale, chert, limestone, and basalt. The region drains to the Scott and Shasta Rivers.[7]
The Klamath Mountains are a rugged and lightly-populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast Ranges, the Klamath Mountains have a varied geology, with substantial areas of serpentinite and marble, and a climate characterized by moderately cold winters with very heavy snowfall and warm, very dry summers with limited rainfall, especially in the south. As a consequence of the geology and soil types, the mountains harbor several endemic or near-endemic trees, forming one of the largest collections of conifers in the world. The mountains are also home to a diverse array of fish and animal species, including black bears, large cats, owls, eagles, and several species of Pacific salmon. Millions of acres in the mountains are managed by the United States Forest Service. The northernmost and largest sub-range of the Klamath Mountains are the Siskiyou Mountains.
The Siskiyou Mountains are a coastal subrange of the Klamath Mountains, and located in northwestern California and southwestern Oregon in the United States. They extend in an arc for approximately 100 miles (160 km) from east of Crescent City, California, northeast along the north side of the Klamath River into Josephine and Jackson counties in Oregon. The mountain range forms a barrier between the watersheds of the Klamath River to the south and the Rogue River to the north. Accordingly, much of the range is within the Rogue River – Siskiyou and Klamath national forests, and the Pacific Crest Trail follows a portion of the crest of the Siskiyous.
The Trinity Alps are a mountain range in Trinity County and Siskiyou County in Northern California. They are a subrange of the Klamath Mountains located to the north of Weaverville.
The Northern California coastal forests are a temperate coniferous forests ecoregion of coastal Northern California and southwestern Oregon.
The Shasta–Trinity National Forest is a federally designated forest in northern California, United States. It is the largest National Forest in California and is managed by the U.S. Forest Service. The 2,210,485 acre forest encompasses five wilderness areas, hundreds of mountain lakes and 6,278 miles (10,103 km) of streams and rivers. Major features include Shasta Lake, the largest man-made lake in California and Mount Shasta, elevation 14,179 feet (4,322 m).
Eldorado National Forest is a U.S. National Forest located in the central Sierra Nevada mountain range, in eastern California.
California mixed evergreen forest is a plant community found in the mountain ranges of California and southwestern Oregon.
The Coast Ranges of California span 400 miles (644 km) from Del Norte or Humboldt County, California, south to Santa Barbara County. The other three coastal California mountain ranges are the Transverse Ranges, Peninsular Ranges and the Klamath Mountains.
California oak woodland is a plant community found throughout the California chaparral and woodlands ecoregion of California in the United States and northwestern Baja California in Mexico. Oak woodland is widespread at lower elevations in coastal California; in interior valleys of the Coast Ranges, Transverse Ranges and Peninsular Ranges; and in a ring around the California Central Valley grasslands. The dominant trees are oaks, interspersed with other broadleaf and coniferous trees, with an understory of grasses, herbs, geophytes, and California native plants.
The Red Buttes Wilderness is a wilderness area in the Klamath and Rogue River national forests in the U.S. states of Oregon and California. It comprises 19,940 acres (8,070 ha), approximately 16,190 acres (6,550 ha) of which is located in California, and 3,750 acres (1,520 ha) in Oregon. It was established by the California Wilderness Act of 1984 and the Oregon Wilderness Act of 1984.
The Rogue–Umpqua Divide Wilderness is a wilderness area located in the Rogue River – Siskiyou and Umpqua National Forests in the Klamath Mountains of Oregon, United States. It was established by the United States Congress in 1984 and comprises 33,200 acres (13,400 ha).
The Coast Range ecoregion is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in the U.S. states of Washington, Oregon, and California. It stretches along the Pacific Coast from the tip of the Olympic Peninsula in the north to the San Francisco Bay in the south, including Grays Harbor, Willapa Bay, and the Long Beach Peninsula in Washington, the entire length of the Oregon Coast, and the Northern California Coast. Named for the Coast Range mountains, it encompasses the lower elevations of the Olympic Mountains, the Oregon Coast Range, the Californian North Coast Ranges, and surrounding lowlands.
The Willamette Valley ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency in the U.S. states of Oregon and Washington. Slightly larger than the Willamette Valley for which it is named, the ecoregion contains fluvial terraces and floodplains of the Willamette River system, scattered hills, buttes, and adjacent foothills. It is distinguished from the neighboring Coast Range, Cascades, and Klamath Mountains ecoregions by lower precipitation, lower elevation, less relief, and a different mosaic of vegetation. Mean annual rainfall is 37 to 60 inches, and summers are generally dry. Historically, the region was covered by rolling prairies, oak savanna, coniferous forests, extensive wetlands, and deciduous riparian forests. Today, it contains the bulk of Oregon's population, industry, commerce, and agriculture. Productive soils and a temperate climate make it one of the most important agricultural areas in Oregon.
The Cascades ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the U.S. states of Washington, Oregon, and California. Somewhat smaller than the Cascade mountain range for which it is named, the ecoregion extends north to Snoqualmie Pass, near Seattle, and south to Hayden Pass, near the Oregon-California border, including the peaks and western slopes of most of the High Cascades. A discontiguous section is located on Mount Shasta in California.
The Eastern Cascades Slopes and Foothills ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the U.S. states of Oregon, Washington, and California. In the rain shadow of the Cascade Range, the eastern side of the mountains experiences greater temperature extremes and receives less precipitation than the west side. Open forests of ponderosa pine and some lodgepole pine distinguish this region from the Cascades ecoregion, where hemlock and fir forests are more common, and from the lower, drier ecoregions to the east, where shrubs and grasslands are predominant. The vegetation is adapted to the prevailing dry, continental climate and frequent wildfire. Volcanic cones and buttes are common in much of the region.
The Russian Wilderness is a wilderness area of 12,000 acres (49 km2) located approximately 65 miles (105 km) northeast of Eureka in northern California. It is within the Klamath National Forest in Siskiyou County and is managed by the US Forest Service. It was added to the National Wilderness Preservation System when the US Congress passed the California Wilderness Act of 1984.
The California montane chaparral and woodlands is an ecoregion defined by the World Wildlife Fund, spanning 7,900 square miles (20,000 km2) of mountains in the Transverse Ranges, Peninsular Ranges, and Coast Ranges of southern and central California. The ecoregion is part of the larger California chaparral and woodlands ecoregion, and belongs to the Mediterranean forests, woodlands, and scrub biome.
The California interior chaparral and woodlands ecoregion covers 24,900 square miles (64,000 km2) in an elliptical ring around the California Central Valley. It occurs on hills and mountains ranging from 300 feet (91 m) to 3,000 feet (910 m). It is part of the Mediterranean forests, woodlands, and scrub biome, with cool, wet winters and hot, dry summers. Temperatures within the coast can range from 53° to 65 °F and 32° to 60 °F within the mountains. Many plant and animal species in this ecoregion are adapted to periodic fire.
↑ Norse, Elliott A.; Raven, Peter H. (1989). Ancient Forests of the Pacific Northwest: Sustaining Biological Diversity and Timber Production in a Changing World. Wilderness Society (U.S.). Washington, D.C.: Island Press. ISBN1-55963-016-7.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
