The Coastal Uplands ecoregion includes the headlands, high marine terraces, hills, and low mountains surrounding the Coastal Lowlands, with medium to high gradient tannic streams. Elevation varies from 400 to 2500 feet (120 to 760 m). The climate is marine-influenced with an extended winter rainy season and minimal seasonal temperature extremes. Abundant fog during the summer dry season reduces vegetation moisture stress. The Uplands region roughly corresponds with the historic distribution of Sitka spruce. After extensive logging, most of the Sitka spruce is gone, and today the forests are dominated by Douglas-fir and western hemlock, with a shrub layer of salal, sword fern, vine maple, Oregon grape, rhododendron, and evergreen blueberry. Wetter slopes and riparian areas feature red alder, bigleaf maple, and western redcedar, with a salmonberry and currant understory. The headlands are covered by grasslands. The region is nearly three times the size of the Coastal Lowlands, covering 1,431 square miles (3,706km2) in Washington and 1,117 square miles (2,893km2) in Oregon. Public lands include the Drift Creek Wilderness, the Siuslaw National Forest, and the Lewis and Clark and Cape Meares national wildlife refuges.[1][2]
Low Olympics (1c)
The Low Olympics ecoregion contains foothills and lower mountains of the Olympic Range, with U-shaped valleys and high gradient streams. It rises to an elevation of approximately 4,000 feet (1,219m). Higher areas were glaciated. Copious precipitation (up to 200 inches (5,080mm) a year) supports a lush, epiphyte-rich rainforest of western hemlock, western red cedar, and Douglas-fir, with Pacific silver fir at higher elevations. Riparian zones support red alder and bigleaf maple forests. Much of the region is in the third rotation of logging, including land within the Olympic National Forest. However, a portion of the region lies within Olympic National Park and contains ancient forests with extremely high biomass. The region covers 1,685 square miles (4,364km2), entirely on the Olympic Peninsula of Washington. The higher elevations of the Olympic Mountains to the east are designated as part of the North Cascades ecoregion.[2]
Volcanics (1d)
The Volcanics ecoregion consists of steeply sloping mountains and capes underlain by fractured basaltic rocks. Elevation generally varies from 600 to 4100 feet (180 to 1250 m), although in some places the volcanic rock extends down to sea level. The region is marked by columnar and pillow basaltoutcrops. Its mountains may have been offshore seamounts engulfed by continental sediments about 200 million years ago. High gradient, cascading streams and rivers occur, and the basaltic substrate preserves summer flows that are more consistent than streams on the sedimentary rocks in surrounding ecoregions. The streams still support runs of spring chinook salmon and summer steelhead. The region's Douglas-fir plantations are heavily logged. Mature forests consist of Douglas-fir, western hemlock, salal, sword fern, vine maple, Oregon grape, and rhododendron. Wetter slopes and riparian areas may support western redcedar, bigleaf maple, red alder, salmonberry, and oxalis. Grassy coastal headlands and mountaintop balds feature Roemer's fescue, thin bentgrass, California oatgrass, and diverse forbs. This large but disjunct ecoregion covers 2,043 square miles (5,291km2) in Oregon and 1,542 square miles (3,994km2) in Washington, including parts of the Olympic and Siuslaw National Forests and the Cummins Creek and Rock Creek Wildernesses, as well as higher elevations in the Cape Meares National Wildlife Refuge.[1][2]
Outwash (1e)
The Outwash ecoregion is a gently sloping fan of glacial outwash material that forms a series of undulating terraces and plateaus. Elevation varies from 20 to 1000 feet (6 to 300 m). The region lies outside the zone of marine influence, and its medium gradient streams and rivers have lower summer flow than most other parts of the Coast Range. Mature forest types include Douglas-fir, western hemlock, red alder, bigleaf maple, and western red cedar, but today the region is largely dominated by industrial timber plantations. It is the smallest of the Coast Range subregions, covering 354 square miles (917km2) in Grays Harbor County north of Aberdeen, Washington.[2]
The Willapa Hills ecoregion (named for the Willapa Hills) consists of low, rolling hills and low, gently sloping mountains with medium gradient streams and rivers. It rises to an elevation of approximately 1,300 feet (396m). This region has a lower drainage density than other upland areas in the Coast Range. Logging is relatively easy and less expensive in this accessible terrain, and industrial timberland has almost completely replaced the historic forests. When disturbed, the silt- and clay-textured soils are easily eroded, thereby degrading stream quality. The vegetation consists of Douglas-fir and western hemlock forests, with sword fern, vine maple, salal, Oregon grape, and rhododendron shrub layer. Wetter slopes and riparian areas support red alder, western redcedar, bigleaf maple, salmonberry, and oxalis. Large herds of Roosevelt elk winter in the region. The region covers 1,277 square miles (3,307km2) in southwestern Washington and 751 square miles (1,945km2) in northwestern Oregon, inland from the coast.[1][2]
Mid-Coastal Sedimentary (1g)
The mountainous Mid-Coastal Sedimentary ecoregion lies outside of the coastal fog zone and is typically underlain by massive beds of sandstone and siltstone. Elevation varies from 300 to 3000 feet (90 to 900 m). The region is more rugged than the geologically similar Willapa Hills. Its Douglas-fir forests are intensively managed for logging, and the slopes are prone to failure when disturbed, particularly south of the Siuslaw River. Stream sedimentation is higher than in the Volcanics ecoregion. The mature forest consists of Douglas-fir and western hemlock, with salal, sword fern, vine maple, Oregon grape, and rhododendron; tanoak may be found on drier slopes to the south. Wetter slopes and riparian areas support bigleaf maple, western redcedar, grand fir, red alder, salmonberry, and oxalis, with California bay-laurel in the south. This is the largest of the Coast Range subregions, covering 3,739 square miles (9,684km2) in the Central and Southern Oregon Coast Range.[1][2]
The Southern Oregon Coastal Mountains ecoregion is a geologically and botanically diverse ecoregion that is a transition zone between the Coast Range and the Siskiyou Mountains, which form part of the Klamath Mountains ecoregion to the east. Rising to an elevation of approximately 4,000 feet (1,219m), this region has the climate of the Coast Range but the varied lithology of the higher, more dissected Siskiyou Mountains, underlain by Jurassic sandstone, metamorphosed sediments, granite, and serpentinite. Distributions of northern and southern vegetation blend together here and species diversity is high. Douglas-fir, western hemlock, tanoak, Port Orford cedar, and western redcedar are present, along with salal, sword fern, vine maple, Oregon grape, rhododendron, California bay-laurel, bigleaf maple, grand fir, red alder, salmonberry, and oxalis. The region covers 692 square miles (1,792km2) in a remote area of Curry County in southwestern Oregon containing the Sixes and Elk River drainages. It includes Grassy Knob Wilderness within the Siskiyou National Forest.[1][2]
Northern Franciscan Redwood Forest (1i)
Map of Coast Range ecoregion in California
The low mountains of the Northern Franciscan Redwood Forest ecoregion lie entirely in the coastal fog zone and are characteristically covered by fog-dependent coast redwood and Douglas-fir. Historically, unbroken redwood forests occurred and moderated local climate by trapping coastal fog and producing shade. The combination of shade, root competition, young soils with a deep organic debris layer on the soil surface, occasional fire, and silting by floods limits the number of plant species. The region extends north only about 10 miles (16km) into Oregon near Brookings. In some factors, this region has more similarities to the temperate rain forests of the Oregon and Washington Coast Ranges than to redwood forest regions to the south. Dominated by conifers, the region also includes western hemlock, western redcedar, Port Orford cedar, grand fir, and some Sitka spruce near the coast. Hardwoods such as red alder and tanoak occur. Fine and fine-loamy, isomesic, Ultisols and Alfisols are typical soils.[6]
King Range / Mattole Basin (1j)
In contrast to the redwood forests to the north and south, the vegetation of the King Range/Mattole Basin ecoregion includes a mixed evergreen forest of Douglas-fir, tanoak, and madrone, as well as areas of grassland. Prairies and coastal scrub cover many of the headlands. Although this is one of the wettest spots in California, the King Range rises above the coastal fog. In summer, warm, dry, offshore winds also help keep the fog away, making the King Range too dry to support the redwood forests that surround it on three sides. The King Range thrusts 4,000 feet (1,200m) above the Pacific, making this area one of the more spectacular and remote stretches of coastline in the continental United States. In the northern part of the region, the Bear and Mattole Rivers drain a hilly-to-steep landscape of mixed evergreen forest, with a land cover that includes a relatively greater amount of annual grasslands than in Ecoregions 1i to the north or 1k to the south. Timber production, livestock grazing, and recreation are primary land uses.[6]
Coastal Franciscan Redwood Forest (1k)
The main part of the Coastal Franciscan Redwood Forest ecoregion extends through Mendocino County from just south of the King Range to just south of the Russian River in Sonoma County. Unlike the conifer-dominated forests of Ecoregion 1i to the north, these central redwood forests typically are more a mixture of conifers and hardwoods. Vegetation includes a multi-story canopy of redwood, Douglas-fir, tanoak, bigleaf maple, evergreen shrubs, and various grasses. In the southern parts of the region, there are more coast live oaks and grassland savannas that are intermixed with denser areas of forest. The near-coastal part of the region that is influenced more by fog has more redwoods and similarities to Ecoregion 1i to the north. Soil temperature regimes are mostly isomesic and mesic. Soil moisture regimes are predominantly udic, ustic, and xeric. Runoff is rapid and many of the smaller streams are dry by the end of the summer. Natural lakes are absent.[6]
Fort Bragg / Fort Ross Terraces (1l)
The Fort Bragg/Fort Ross Terraces ecoregion forms an elevated coastal plain that has less relief (200–800 feet or 61–244 metres) than the adjacent mountains of Ecoregion 1k. Quaternary and Tertiarysandstones and mudstones form the terraces, and some areas are deeply dissected, forming ravines that expose Cretaceoussedimentary rocks. Elevations range from sea level to about 1,300 feet (400m). Soil moisture regimes are udic and some aquic, and soil temperatures are isomesic. Monthly and annual temperature variations are minimal and summer fog is common. Vegetation includes coastal grasslands and shrubs, stunted beach pine, Bishop pine, or pygmy cypress, along with areas of some grand fir and western hemlock. Terrace soils typically are unsuitable for redwoods, although they do occur in ravines and on some bluffs.[6]
Ecoregions of the San Francisco Bay Area, including sub-regions of the Coast Range
A small outlier of the region occurs in the south in Marin County that includes the coniferous and hardwood forests of Mount Tamalpais and Bolinas Ridge. This small area of redwoods and other forest types ranges in elevation from sea level to more than 2,500 feet (760m). It has more relief and coniferous forest than the Marin Hills ecoregion (6o). Various types of coniferous and hardwood forests occur, composed mostly of Douglas-fir, redwoods, tanoak, madrone, California bay, and coast live oak. Mount Tamalpais and Bolinas Ridge force moisture out of the air as it cools and ascends the steep western mountain faces. These western parts are heavily forested with redwoods and Douglas-fir. A few areas of drier exposures or shallow soils contain grasslands, coastal scrub, or chaparral.[6]
Santa Cruz Mountains (1n)
The Santa Cruz Mountains ecoregion covers the western and southwestern parts of the range where vegetation includes redwood, Douglas-fir, tanoak, coast live oak, and California bay, along with some chaparral and coastal scrub species. The shrub layer under forest canopy generally is sparse. Species of limited range in this area include the Santa Cruz cypress and Shreve oak. Forests of this region are ecologically and genetically distinct from those of the redwood ecoregions (1i, 1k) farther north. Clear-cut logging was typical from the late 1800s to about the 1960s. Most logging now uses smaller selective cuts. Climate varies from the west to the east, as the high mountain ridges reduce the penetration of maritime air. Winters are cool and wet. On the western side, summers are cool, and fog or low overcast is typical. Soil temperature regimes are mostly mesic and isomesic, with some thermic. Soil moisture regimes are mostly ustic and xeric. Streams on the northeastern side of the mountains generally are dry during the summer, but streams on the seaward side generally are perennial.[6]
San Mateo Coastal Hills (1o)
The San Mateo Coastal Hills ecoregion has lower relief and elevations than Ecoregion 1n, with more coastal scrub vegetation and a few small areas of cropland rather than the denser forest and woodland of the Santa Cruz Mountains ecoregion (1n). Marine terraces, coastal benches, and small valleys are the primary landforms. Elevations range from sea level to about 1,000 feet (300m). Pliocenesandstone and siltstone are the main rock types compared to the mix of geology in Ecoregion 1n that includes older sedimentary and some igneous rocks. Mollisol soil type is typical, with mostly thermic to isomesic temperature regimes. Soil moisture regimes are mostly xeric and ustic. Summer fog is common and winters are cool and moist.[6]
Clearcutting and road building, as in this area near the source of the Lewis and Clark River, may contribute to slope failure and affect surface water quality.
Alnus rubra, the red alder, is a deciduous broadleaf tree native to western North America.
Temperate rainforests are rainforests with coniferous or broadleaf forests that occur in the temperate zone and receive heavy rain.
The Pacific temperate rainforests of western North America is the largest temperate rain forest region on the planet as defined by the World Wildlife Fund. The Pacific temperate rainforests lie along the western side of the Pacific Coast Ranges along the Pacific Northwest Coast of North America from the Prince William Sound in Alaska through the British Columbia Coast to Northern California, and are part of the Nearctic realm, as also defined by the World Wildlife Fund. The Pacific temperate rain forests are characterized by a high amount of rainfall, in some areas more than 300 cm (10 ft) per year and moderate temperatures in both the summer and winter months.
The Northern California coastal forests are a temperate coniferous forests ecoregion of coastal Northern California and southwestern Oregon.
California mixed evergreen forest is a plant community found in the mountain ranges of California and southwestern Oregon.
Drift Creek Wilderness is a 5,798-acre (2,346 ha) wilderness area in the Siuslaw National Forest on the Oregon Coast. It was created in 1984, along with two other small wilderness areas in the forest - Cummins Creek Wilderness and Rock Creek Wilderness. The elevation of Drift Creek ranges from 150 to 1,500 feet, and is characterized by long steep slopes with broken and uneven terrain. Drift Creek was named for the accumulations of driftwood on its banks.
The Cummins Creek Wilderness is a 9,300-acre (3,800 ha) wilderness area in the Siuslaw National Forest within the Oregon Coast. It is one of three wilderness areas created in the Siuslaw in 1984, along with Drift Creek and Rock Creek. It is "dedicated to preserve in a wilderness state, the last remaining virgin stands of Sitka spruce, western hemlock and Douglas-fir, in Oregon's coast lands." Cummins Creek and nearby Cummins Ridge are named for F.L. Cummins, an early homesteader.
The Rock Creek Wilderness is a wilderness area comprising 7,486 acres (3,029 ha) within the Siuslaw National Forest on the Oregon Coast. It was created in 1984, along with the Drift Creek Wilderness and Cummins Creek Wilderness. The Rock Creek Wilderness has "no developed trails or trailheads."
The Northern Oregon Coast Range is the northern section of the Oregon Coast Range, in the Pacific Coast Ranges physiographic region, located in the northwest portion of the state of Oregon, United States. This section of the mountain range, part of the Pacific Coast Ranges, contains peaks as high as 3,710 feet (1,131 m) for Rogers Peak. Forests in these mountains are considered to be some of the most productive timber land in the world. The Central Oregon Coast Range is directly south of this section with the Southern Oregon Coast Range beyond the central range.
The Central Oregon Coast Range is the middle section of the Oregon Coast Range, in the Pacific Coast Ranges physiographic region, and located in the west-central portion of the state of Oregon, United States roughly between the Salmon River and the Umpqua River and the Willamette Valley and the Pacific Ocean. This approximately 90-mile (140 km) long mountain range contains mountains as high as 4,097 feet for Marys Peak. Portions of the range are inside the Siuslaw National Forest and three wilderness areas exist as well: Drift Creek Wilderness, Cummins Creek Wilderness and Rock Creek Wilderness.
The Siuslaw National Forest is a national forest in western Oregon in the United States. Established in 1908, the Siuslaw is made up of a wide variety of ecosystems, ranging from coastal forests to sand dunes.
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 Blue Mountains ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the Pacific Northwest, mainly in the state of Oregon, with small areas over the state border in Idaho and southeastern Washington. It is also contiguous with the World Wildlife Fund's Blue Mountain forests ecoregion.
The Klamath Mountains ecoregion of Oregon and California lies inland and north of the Coast Range ecoregion, extending from the Umpqua River in the north to the Sacramento Valley in the south. It encompasses the highly dissected ridges, foothills, and valleys of the Klamath and Siskiyou Mountains. It corresponds to the Level III ecoregion designated by the Environmental Protection Agency and to the Klamath-Siskiyou forests ecoregion designated by the World Wide Fund for Nature.
The biogeoclimatic zones of British Columbia are units of a classification system used by the British Columbia Ministry of Forests for the Canadian province's fourteen different broad, climatic ecosystems. The classification system, termed Biogeoclimatic Ecosystem Classification, exists independently of other ecoregion systems, one created by the World Wildlife Fund and the other in use by Environment Canada, which is based on one created by the Commission for Environmental Cooperation (CEC) and also in use by the US Environmental Protection Agency (EPA). The system of biogeoclimatic ecosystem classification was partly created for the purpose of managing forestry resources, but is also in use by the British Columbia Ministry of Environment and Climate Change Strategy and other provincial agencies. A biogeoclimatic zone is defined as "a geographic area having similar patterns of energy flow, vegetation and soils as a result of a broadly homogenous macroclimate."
The Ecology of the North Cascades is heavily influenced by the high elevation and rain shadow effects of the mountain range. The North Cascades is a section of the Cascade Range from the South Fork of the Snoqualmie River in Washington, United States, to the confluence of the Thompson and Fraser Rivers in British Columbia, Canada, where the range is officially called the Cascade Mountains but is usually referred to as the Canadian Cascades. The North Cascades Ecoregion is a Level III ecoregion in the Commission for Environmental Cooperation's classification system.
The Central Pacific coastal forests is a temperate coniferous forest ecoregion located in the Canadian province of British Columbia and the U.S. states of Oregon and Washington, as defined by the World Wildlife Fund (WWF) categorization system.
Pseudotsuga menziesii var. menziesii, commonly known as Coast Douglas-fir, Pacific Douglas-fir, Oregon pine, or Douglas spruce, is an evergreen conifer native to western North America from west-central British Columbia, Canada southward to central California, United States. In Oregon and Washington its range is continuous from the Cascades crest west to the Pacific Coast Ranges and Pacific Ocean. In California, it is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Mountains with a small stand as far south as the Purisima Hills, Santa Barbara County. In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to 1,800 metres (5,900 ft) in the California Mountains. Further inland, coast Douglas-fir is replaced by Rocky Mountain or interior Douglas-fir. Interior Douglas-fir intergrades with coast Douglas-fir in the Cascades of northern Washington and southern British Columbia.
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