The Southern Oregon Coast Range is the southernmost section of the Oregon Coast Range, in the Pacific Coast Ranges, 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

Umpqua Valley The Umpqua River ( ) on the Pacific coast of Oregon in the United States is approximately long. One of the principal rivers of the Oregon Coast and known for bass and shad, the river drains an expansive network of valleys in the mountains west ...

and to the west the Pacific Ocean. This approximately -long mountain range contains mountains as high as for Bone Mountain. The mountains are known locally in the Roseburg area as the Callahan Mountains, or simply as The Callahans.

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 North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

more than 60 million years ago.Orr, Elizabeth and William Orr, and Ewart Baldwin. Geology of Oregon. Kendall/Hunt Publishing, 1992, 4th edition. In the Southern Range the 64-million-year-old Roseburg Volcanics that formed this section are the oldest portions of the entire range. The range is part of a

forearc basin Forearc is a plate tectonic term referring to a region between an oceanic trench, also known as a subduction zone, and the associated volcanic arc. Forearc regions are present along a convergent margins and eponymously form 'in front of' the vol ...

that has slowly rotated about 51 degrees since the Eocene period. Much of the mountain structures are

pillow basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...

formations created during the volcanic period and then uplifted with the collision into the North American Plate. Other geologic features are mainly the result of erosion and weather forces carving steam beds and valleys out of the rock formations.

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. Field Guide to the Forested Plant Associations of the Northern Oregon Coast Range: Wildlife Habitat Relationships for the Coast Guide.
(PDF) ECOSHARE. Retrieved on June 26, 2007. Birds living in the Southern Coast Range include a variety of smaller and larger bird species. These include northern goshawks,

peregrine falcon The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a Cosmopolitan distribution, cosmopolitan bird of prey (Bird of prey, raptor) in the family (biology), family Falco ...

s, pileated woodpeckers, olive-sided flycatcher, and western bluebirds.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. The northern spotted owl, listed as a threatened species by the United States also inhabit the mountain forests.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.
(PDF) U.S. Forest Service. Retrieved on June 26, 2007. Aquatic life includes river lamprey, Pacific lamprey,

coastal cutthroat trout The coastal cutthroat trout (''Oncorhynchus clarkii clarkii''), also known as the sea-run cutthroat trout, blue-back trout or harvest trout, is one of the several subspecies of cutthroat trout found in Western North America. The coastal cutthroa ...

, Millicoma longnose dace, Umpqua chub, red-legged frogs, southern seep salamander, western pond turtles, coho salmon, Chinook salmon, steelhead trout, and others. 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. Other small animals include shrews, moles, deer mice, and ermine.Aubry, Keith B., Mark J. Crites, and Stephen D. West
Regional Patterns of Small Mammal Abundance and Community Composition in Oregon and Washington.
(PDF) U.S. Forest Service. Retrieved on June 26, 2007. Plants include large stands of Douglas-fir trees, western hemlock forests, cedar trees, with portions of these forests including old-growth stands. Other flora include

Sitka spruce ''Picea sitchensis'', the Sitka spruce, is a large, coniferous, evergreen tree growing to almost tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth-larg ...

, salmonberry, salal, tanoak, and western azalea.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. Portions of the range are in the

Elliott State Forest Elliott State Forest is a state forest in Coos and Douglas counties of the U.S. state of Oregon, between Coos Bay and Reedsport in the Oregon Coast Range. The first state forest established in Oregon, it is named after the state's first state fo ...

Location and climate

The range begins around the Umpqua River with the Central Oregon Coast Range to the north.

Oregon Route 38 Oregon Route 38 is an Oregon state highway that runs between the city of Reedsport, on the Oregon Coast, and an interchange with Interstate 5 near the communities of Curtin and Anlauf. It is also known as most of the Umpqua Highway No. 45 (see ...

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. The climate of the mountains is of the mild maritime variety. It is characterized by cool dry summers followed by mild and wet winters. Most precipitation falls in the form of rain, with snow during the winter months at the higher elevations. Annual precipitation varies from , with more in the higher elevations. The average high temperature in January is , and the average high in July is with temperature also varying by elevation.

Peaks

All peaks in the range are over in elevation.

Rivers

The following rivers have portions of their headwaters in the Southern Oregon Coast Range: *Drains to Pacific Ocean: **

Coos River The Coos River flows for about into Coos Bay along the Pacific coast of southwest Oregon in the United States. Formed by the confluence of its major tributaries, the South Fork Coos River and the Millicoma River, it drains an important timber-pro ...

** Coquille River ** Umpqua River

References

External links

* {{Oregon Coast Range * Mountain ranges of Oregon Landforms of Douglas County, Oregon Landforms of Coos County, Oregon