Mount McLoughlin is a dormant steep-sided stratovolcano, or composite volcano, in the Cascade Range of southern Oregon, United States. Located in the Sky Lakes Wilderness, it is one of the volcanic peaks in the Cascade Volcanic Arc, within the High Cascades sector. A prominent landmark for the Rogue River Valley, the mountain is north of Mount Shasta, and south-southwest of Crater Lake. It was named around 1838 after John McLoughlin, a Chief Factor for the Hudson's Bay Company. Mount McLouglin's prominence has made it a landmark to Native Americans and others for thousands of years.
McLoughlin consists largely of basaltic andesite. It underwent three major eruptive periods before its last activity took place between 30,000 and 20,000 years ago. It is not currently monitored for activity or deformation. Diverse species of flora and fauna inhabit the area, which is subject to frequent snowfall and temperature variation between seasons. The Pacific Crest Trail skirts the eastern and northern sides and also accesses the only trail to the summit, the McLoughlin Trail 3716. The mountain can also be skied.
Geography
thumb|left|upright=1.15|Location in Oregon relative to other major volcanoes
The major landmark for the Rogue River Valley, Mount McLoughlin reaches an elevation of .
The volcano includes the Wilámxa Tip and Máalsi Tip peaks, which occur on its flanks at elevations of
and
, respectively. It can be seen from the Interstate 5 and U.S. Route 97 highways. From the southwest and southeast, it has a symmetrical appearance, but the northeastern flank of the volcano has been eroded and transformed into a hollow amphitheater.
Wilderness
McLoughlin lies within the Sky Lakes Wilderness area, The wilderness area encompasses more than 200 bodies of water including ponds and lakes, in addition to forests and mountain ridges.
Ecology
About 20 tree species can be found throughout Mount McLoughlin's surroundings, including Pacific yew at low elevations, mountain hemlock, whitebark pine, and subalpine fir at higher elevations, and lodgepole pine and red fir throughout.
Nearby features
thumb|left|View of [[Pelican Butte and Fourmile Lake from near summit]]
Two nearby volcanoes closely resemble Mount McLoughlin in composition. Brown Mountain, a shield volcano with a volume of , lies to the southeast, while Pelican Butte, the most prominent shield volcano in the southern Cascades of Oregon, lies to the east.
Brown Mountain has been dated to between 60,000 and 12,000 years old. It produced basaltic andesite lava flows that have not been heavily eroded, but during Pleistocene glacial advance, ice streams on the volcano ate away at the cinder cone that formed Brown Mountain's summit. This formed a glacial cirque with a bowl shape on the northeastern flank.
Pelican Butte reaches an elevation of , and it features gradual slopes. Adjacent to Klamath Lake, it has a greater volume than McLoughlin at , and it is made up of basaltic andesite. Like Brown Mountain, Pelican Butte has a cinder cone on the top of its summit, in addition to a glacial cirque and ravine that were excavated on its northeastern side. These eroded areas exhibit pyroclastic rock in a matrix with lava flows, suggesting that blocky and ʻaʻā lavas formed an outer shell around Pelican Butte's fragmented interior. Glaciation has also lowered the overall volcano by tens of yards.
Other volcanoes can be found within the Sky Lakes Wilderness area, including lava flows and mud flows at Big Bunchgrass Butte and Imagination Peak, in addition to more recent eruptive activity at Goosenest Mountain in the northeastern sector.
Eruptive history
thumb|right|Mount McLoughlin from the Upper Klamath Lake, showing its summit cone
Mount McLoughlin underwent at least three distinct eruptive phases. The volcano is not currently monitored for activity or deformation. The closest seismic monitoring stations lie to the south near Mount Shasta and the Medicine Lake Volcano.
Human history
thumb|right|170px|Mount McLoughlin got its official name from [[John McLoughlin (pictured), a factor for the Hudson's Bay Company]]
McLouglin has served as a landmark to Native American populations and others for thousands of years. Indigenous peoples utilized the area to hunt and gather berries. also appearing in maps as Mount Pitt, Mount Simpson, and Mount Jackson. after Dr. John McLoughlin, a factor for the Hudson's Bay Company noted for helping American settlers in the 1830s and 1840s. An important figure in the local fur trade, McLoughlin was also known as the "Father of Oregon".
The area around Mount McLoughlin was frequented by fur trappers and explorers, but they did not settle for long stays in the area. a six hour round-trip which gains about in elevation. While the route receives moderate to heavy use each year, ascent to the peak is easiest from July through September, when the trailhead is accessible by vehicle and snow is minimal along the path. Although there is a creek crossing at the beginning of the trail that currently requires walking across a log or wading through the water until a new bridge is built.
The Mt. McLoughlin Trailhead is on Forest Road 3650, north of Oregon Route 140. After about , the Mt. McLoughlin Trail joins the Pacific Crest Trail for half a mile, then passes through a forested area for about before reaching timberline. The last mile of the route travels over blocky lava and rubble, and the trail above the tree line is less clearly delineated. From the summit, Mount Shasta and Crater Lake can be seen.
During the winter, the climb requires snowshoes, crampons, and ice axes, and is far more challenging than the popular summertime route. The access road from Oregon Route 140 may also be closed due to snow, requiring a longer approach on snowshoes or cross country skis. The mountain can also be skied, which has become more popular in recent years.
See also
- Volcanic Legacy Scenic Byway
Notes
- [a] Other sources list the elevation as .