Southern Oregon Coast Range

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Coordinates: 43°16′33″N 123°53′60″W / 43.275780, -123.899960

Southern Oregon Coast Range
Range
Country United States
State Oregon
Part of Oregon Coast Range, Pacific Coast Ranges
Borders on Central Oregon Coast Range, Siskiyou Mountains
Highest point Bone Mountain
 - elevation 3,547 ft (1,081 m)
 - coordinates 42°54′58.1″N 123°51′00.1″W / 42.916139, -123.850028
Length 55 mi (89 km), North-South
Geology volcanic, forearc basin
Period Paleocene, Eocene

The Southern Oregon Coast Range is the southernmost section of the Oregon Coast Range located in the southwest portion of the state of Oregon, United States roughly between the Umpqua River and the middle fork of the Coquille River, beyond which are the Klamath Mountains. To the east is the Willamette Valley and to the west the Pacific Ocean. This approximately 55 mile long mountain range contains mountains as high as 3,547 feet for Bone Mountain.[1]

Contents

[edit] Geology

As with the Oregon Coast Range as a whole, the Southern Oregon Coast Range likely began as an ocean island chain that collided with the continental tectonic plate of North America more than 60 million years ago.[2] In the Southern Range the 64 million year old Roseburg volcanics that formed this section are the oldest portions of the entire range.[2] The range is part of a forearc basin that has slowly rotated about 51 degrees since the Eocene period.[2] Much of the mountain structures are pillow basalt formations created during the volcanic period and then uplifted with the collision into the continental plate.[2] Other geologic features are mainly the result of erosion and weather forces carving steam beds and valleys out of the rock formations.[2]

[edit] Flora and fauna

The Oregon Coast Range is home to over 50 mammals, 100 species of birds, and nearly 30 reptiles or amphibians that spent a significant portion of their life cycle in the mountains.[3] Birds living in the Southern Coast Range include a variety of smaller and larger bird species.[4] These include northern goshawks, peregrine falcons, pileated woodpeckers, olive-sided flycatcher, and western bluebirds.[5] The Northern Spotted Owl, listed as a threatened species by the United States also inhabit the mountain forests.[6] Aquatic life includes river lamprey, Pacific lamprey, coastal cutthroat trout, Millicoma longnose dace, Umpqua chub, red-legged frogs, southern seep salamander, western pond turtles, coho salmon, Chinook salmon, steelhead trout, and others.[5] Other wildlife includes fringed myotis bats, long-legged myotis bats, Townsend’s big-eared bat, fishers, and sharptail snakes, northern flying squirrels, red tree voles, Roosevelt Elk, among others.[5][6][7] Other small animals include shrews, moles, deer mice, and ermine.[8]

Plants include large stands of Douglas-fir trees, western hemlock forests, cedar trees, with portions of these forests including old-growth stands.[6] Other flora include Sitka spruce, salmonberry, salal, tanoak, and western azalea.[9] Portions of the range are in the Elliott State Forest.

[edit] Location and climate

The range begins around the Umpqua River with the Central Oregon Coast Range to the north. Oregon Route 38 is the general divide between the two sections. On the southern end the Coquille River’s middle fork provides the general dividing line between the Central Range and the Klamath Mountains to the south and east.[2]

The climate of the mountains is of the mild maritime variety.[4] It is characterized by cool dry summers followed by mild and wet winters.[4] Most precipitation falls in the form of rain, with snow during the winter months at the higher elevations.[4] Annual precipitation varies from 60 to 120 inches (150-300 cm), with more in the higher elevations.[4] The average high temperature in January is 36.3°F (2.4°C), and the average high in July is 61.9°F (16.6°C) with temperature also varying by elevation.[4]

[edit] Peaks

All peaks in the range over 3,000 feet in elevation.[1]

Mountain Name Elevation County
feet metres
Bone Mountain 3,547 1,081 Coos
Kenyon Mountain 3,300 1,000 Benton
Bear Mountain 3,054 931 Douglas
Buzzard Rock 3,054 931 Douglas

[edit] Rivers

Map of the region with major rivers in blue. Orange line shows divide between watersheds flowing to the coast and those flowing north or east.
Map of the region with major rivers in blue. Orange line shows divide between watersheds flowing to the coast and those flowing north or east.

The following rivers have portions of their headwaters in the Southern Oregon Coast Range:

[edit] See also

[edit] References

  1. ^ a b Northwest GeoData Clearinghouse. Department of Geology - Portland State University. Retrieved on 2008-03-29.
  2. ^ a b c d e f Orr, Elizabeth and William Orr, and Ewart Baldwin. Geology of Oregon. Kendall/Hunt Publishing, 1992, 4th edition.
  3. ^ Field Guide to the Forested Plant Associations of the Northern Oregon Coast Range: Wildlife Habitat Relationships for the Coast Guide. ECOSHARE. Retrieved on June 26, 2007.
  4. ^ a b c d e f McGarigal, Kevin; William C. McComb (August 1995). "Relationships Between Landscape Structure and Breeding Birds in the Oregon Coast Range". Ecological Monographs 65 (3): 235–260. The Ecological Society of America. doi:10.2307/2937059. 
  5. ^ a b c Notice of intent, to conduct scoping meetings. Federal Register: May 9, 2005, pages 24450-24452. (Volume 70, Number 88). U.S. Fish and Wildlife Service. Retrieved on June 26, 2007.
  6. ^ a b c Carey, Andrew B., Janice A. Reid, and Scott P. Horton. Spotted Owl Home Range and Habitat use in Southern Oregon Coast Range. Journal of Wildlife Management. 54(1):11-17. U.S. Forest Service. Retrieved on June 26, 2007.
  7. ^ G. W. Witmer, D. S. deCalesta. Habitat Use by Female Roosevelt Elk in the Oregon Coast Range. The Journal of Wildlife Management, Vol. 47, No. 4 (Oct., 1983), pp. 933-939.
  8. ^ Aubry, Keith B., Mark J. Crites, and Stephen D. West. Regional Patterns of Small Mammal Abundance and Community Composition in Oregon and Washington. U.S. Forest Service. Retrieved on June 26, 2007.
  9. ^ Tarrant, Robert F. and Chris Maser. From the Forest to the Sea: A Story of Fallen Trees: Introduction. Tree Dictionary. Retrieved on June 26, 2007.
v • d • e
Oregon Coast Range
Northern

Five highest peaks: Rogers Peak · South Saddle Mountain · Larch Mountain · Trask Mountain · Saddle Mountain
Central

Five highest peaks: Marys Peak · Grass Mountain · Laurel Mountain · Prairie Peak · Saddle Bag Mountain
Southern

Four highest peaks: Bone Mountain · Kenyon Mountain · Bear Mountain · Buzzard Rock
See also

Pacific Coast Ranges · Tualatin Mountains · Siskiyou Mountains · Calapooya Mountains · Oregon Coast