Mount Washington is a deeply eroded volcano in the Cascade Range of Oregon. It lies within Deschutes and Linn counties and is surrounded by the Mount Washington Wilderness area.
Like the rest of the Oregon Cascades, Mount Washington was produced by the subduction of the oceanic Juan de Fuca tectonic plate under the continental North American tectonic plate, forming during the late Pleistocene. Made mostly of mafic (rich in magnesium and iron) volcanic rock like subalkaline basalt and basaltic andesite, it has a volcanic plug occupying its summit cone and numerous dikes. It is surrounded by other volcanic features such as cinder cones and spatter cones. The volcano's last eruptions took place from spatter cones about 1,350 years ago, generating basaltic andesite lava deposits.
Mount Washington has barren surroundings, which have seen little historical recreational use. A wagon road at McKenzie Pass was built in 1872, which was later paved during the 1930s. On August 26, 1923, the mountain was first ascended by six boys from the neighboring city of Bend. The surrounding area was designated the Mount Washington Wilderness by the federal government in 1964. The wilderness area is not heavily used, though it has a number of hiking trails. Wildlife is sparse in the region. Vegetation is mostly limited to pines and shrubs. Animal life includes deer, American black bear, cougar, various small animal species, and some fish species in the lakes.
Geography
With an elevation of above sea level, Mount Washington is located in Deschutes and Linn counties in the U.S. state of Oregon. It lies north of McKenzie Pass, The volcano forms a crest of steep, icy mountains with North Cinder Peak and Three Fingered Jack to the south of Mount Jefferson. The volcano has a pinnacle appearance resembling the spire-like shape of Mount Thielsen. According to Harris (2005), the volcano resembles Cleopatra's Needle from certain angles and the Sugarloaf Mountain in Brazil from others. The proximal relief for the volcano is , while the draping relief is . The volcano has an overall volume of .
Physical geography
Elevations in the Mount Washington area range from to greater than . Most precipitation falls during the winter as snow, and summers are warm and dry. During the winter season, the Cascades are typically covered with a deep snowpack. Oregon Route 242 over McKenzie Pass is closed from fall through late spring, whereas the Santiam Highway and Oregon Route 126 are maintained and remain open year-round.
The Mount Washington Wilderness includes glacial landforms – specifically outwash plains and lateral, recessional, and terminal ground moraines. Many of these glacial deposits were created from the most recent glacial advance in the late Pleistocene, when there was an ice sheet between Mount Washington and Three Fingered Jack, although there are Holocene glacial deposits as well. The McKenzie River, fed by Clear Lake, runs south for about just west of Mount Washington before it turns west for another and meets the Willamette River near the city of Eugene.
Wilderness
The Mount Washington Wilderness covers an area of . First named a wild area by the United States Forest Service in 1975, it was designated as one of the original wilderness areas under the 1964 Wilderness Act. Located to the west of Bend, the Mount Washington plot is the smallest of three wilderness areas that encompass most of the High Cascades, a physiographic region located in the central part of Oregon; the two others are the Three Sisters Wilderness and Mount Jefferson Wilderness. Used mostly by hunters, hikers, and climbers, It has a summit cone, a volcanic plug comprised by cinder, lava flows, and intrusive rock that covers Washington's volcanic conduit.