wilderness area
Wilderness or wildlands (usually in the plural), are natural environments on Earth that have not been significantly modified by human activity or any nonurbanized land not under extensive agricultural cultivation. The term has traditionally re ...
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
Most of the northern part of the wilderness area, , about 77.5%, is located on
Bureau of Land Management
The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior responsible for administering federal lands. Headquartered in Washington DC, and with oversight over , it governs one eighth of the country's la ...
land and its southern portion, , about 22.5%, is located within the
Gunnison National Forest
The Gunnison National Forest is a U.S. National Forest covering 1,672,136 acres (2,612.71 sq mi, or 6,766.89 km²) Calf Creek Plateau.
The Powderhorn Wilderness is an important watershed for the
Gunnison River
The Gunnison River is located in western Colorado, United States and is one of the largest tributaries of the Colorado River.
Description
The river flows east to west and has a drainage area of according to the USGS. The drainage basin of ...
. The area protects the East, Middle, and West forks of Powderhorn Creek, which flow into Cebolla Creek and then the Gunnison River. Calf Creek, which is on National Forest land, flows south and eventually joins Cebolla Creek. Within the wilderness area there are numerous small lakes and beaver ponds. The largest of these are Devil's Lake and Powderhorn Lake.
Much of the area sits above timberline at and it is recognized as one of the largest expanses of
tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
in the
contiguous United States
The contiguous United States (officially the conterminous United States) consists of the 48 adjoining U.S. states and the Federal District of the United States of America. The term excludes the only two non-contiguous states, Alaska and Hawaii ...
.
Geology
The Powderhorn Wilderness is within the
San Juan volcanic field
The San Juan volcanic field is part of the San Juan Mountains in southwestern Colorado. It consists mainly of volcanic rocks that form the largest remnant of a major composite volcanic field that covered most of the southern Rocky Mountains in t ...
and volcanic rocks dominate the region. The central, highest terrain of the wilderness is composed of
basaltic lava
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...
flows of the Hinsdale Formation, which are dated at 16 to 19 million years old. These lava flows are thought to be among the last volcanic events in the area and are some of the best preserved. The Hinsdale Formation lava flows form an expansive alpine highland where the two highest ridges are Calf Creek Plateau and Cannibal Plateau.
Underlying these basalt flows are sheets of older volcanic rocks that are exposed around the periphery of the wilderness. From youngest to oldest, these rocks include Cochetopa Park Tuff, Nelson Mountain Tuff, Carpenter Ridge Tuff, and
Fish Canyon Tuff
The Fish Canyon Tuff is the large volcanic ash flow or ignimbrite deposit resulting from one of the largest known Explosive eruption, explosive eruptions on Earth, estimated at . (see List of largest volcanic eruptions). The Fish Canyon Tuff erupti ...
. The volcanic ash that formed these tuffs came from
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...
eruptions within the San Juan volcanic field. These eruption sites are the Cochetopa Caldera, San Luis Caldera, Bachelor Caldera, and
La Garita Caldera
La Garita Caldera is a large caldera in the San Juan volcanic field in the San Juan Mountains near the town of Creede in southwestern Colorado, United States.
It is west of La Garita, Colorado. The eruption that created the La Garita Calde ...
, respectively. On the northern and western reaches of the wilderness there are yet older volcanic rocks exposed. These Oligocene lavas and
breccias
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.
The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of d ...
have been dated at 32 million years old.
The Powderhorn Wilderness was
glaciated
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...
, and the most prominent glacial
cirques
A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform ...
are located on the north side of the wilderness. Powderhorn Lakes, popular hiking destinations, are located in one of these cirques.
Flora and fauna
Half of the Powderhorn Wilderness is above
tree line
The tree line is the edge of the habitat at which trees are capable of growing. It is found at high elevations and high latitudes. Beyond the tree line, trees cannot tolerate the environmental conditions (usually cold temperatures, extreme snowp ...
and the
alpine tundra
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated alpine climate, harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alp ...
here is dominated by grasses and forbs, though there are also extensive thickets of willow. Below, the subalpine forest is dominated by Engelmann spruce and subalpine fir, and interspersed are numerous subalpine meadows of grasses and forbs. There are also stands of aspen. At lower elevations, particularly in the northern extension of the wilderness,
montane forests
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...
Sagebrush steppe
Sagebrush steppe is a type of shrub-steppe, a plant community characterized by the presence of shrubs, and usually dominated by sagebrush, any of several species in the genus ''Artemisia''.mule deer
The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer.
Unlike the related whit ...
and
elk
The elk (''Cervus canadensis''), also known as the wapiti, is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. The common ...
bobcats
The bobcat (''Lynx rufus''), also known as the red lynx, is a medium-sized cat native to North America. It ranges from southern Canada through most of the contiguous United States to Oaxaca in Mexico. It is listed as Least Concern on the IUC ...
,
coyotes
The coyote (''Canis latrans'') is a species of canis, canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecologica ...
Travel through the wilderness is limited to those on foot and horseback. There are six trailheads that provide access to the wilderness. To the west is the Devils Creek Trailhead (). Along the north and northeast boundary are the Powderhorn Lake () and Ten Mile Spring () trailheads. And to the south are the Deer Lakes (), Brush Creek (), and Powderhorn Park () trailheads. These trailheads provide access to of interconnecting trails allowing multiple options for trips in the wilderness.Trailhead and trail information is available a Colorado Trail Explorer This includes information on th Powderhorn Lake Trailhead and th Powderhorn Lakes Trail Off-trail distances can also be computed. Accessed 16 February 2021
The most popular destination in the wilderness is Powderhorn Lakes. These two lakes are nestled in a beautiful glacial cirque, and the trip one-way is well worth the effort. Start at the Powderhorn Lake Trailhead and take the well-maintained Powderhorn Lakes Trail south to the lakes. The upper lake is at an elevation of (). Given the popularity of this trail, those seeking remoteness and more solitude may find other trails and destinations more rewarding.