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27-679: The Wallowa Mountains ( / w ə ˈ l aʊ w ə / ) are a mountain range located in the Columbia Plateau of northeastern Oregon in the United States . The range runs approximately 40 miles (64 km) northwest to southeast in southwestern Wallowa County and eastern Union County between the Blue Mountains to the west and the Snake River to the east. The range is sometimes considered to be an eastern spur of

54-511: A concrete dam in 1916, and a new dam was completed in 1929. Columbia Plateau During late Miocene and early Pliocene times, a flood basalt engulfed about 63,000 square miles (160,000 km ) of the Pacific Northwest, forming a large igneous province . Over a period of perhaps 10 to 15 million years, lava flow after lava flow poured out, ultimately accumulating to a thickness of more than 6,000 feet (1.8  km). As

81-475: Is also a common feature of the valleys. The melting of the glaciers produced a large quantity of water, which carried sediment to the valley bottoms, leaving delta deposits on top of the former deposits. In the mountains, much precipitation falls as snow . Total snowfall peaks around March. Most precipitation in the area is orographic precipitation . Near the tops of the mountains, total annual precipitation can exceed 100 inches (250 cm) per year, while in

108-498: Is melting rock beneath the Columbia Plateau Province at the base of the lithosphere (the layer of crust and upper mantle that forms Earth's moving tectonic plates). In an effort to figure out why this area, far from a plate boundary, had such an enormous outpouring of lava, scientists established hardening dates for many of the individual lava flows. They found that the youngest volcanic rocks were clustered near

135-549: The Nez Perce War . Logging came in the late 1880s, using streams and rivers to transport the wood. A dam was constructed on Wallowa Lake in 1884 to help irrigate the valley. In 1908, the first railroad into the valley was completed. Rail lines were built to the upper valley by the Union Pacific Railroad in 1919, allowing for safer transportation of logs. The dam beneath Wallowa Lake was replaced by

162-468: The boundary between the core and mantle . The concentrated heat triggers a plume hundreds of kilometers in diameter that ascends directly through to the surface of the Earth. The track of this hot spot starts in the west and sweeps up to Yellowstone National Park . The steaming fumaroles and explosive geysers are ample evidence of a concentration of heat beneath the surface. The hotspot is stationary, but

189-550: The sedimentary deposits of oceans during the Triassic . At the center of the Batholith are granodioritic rocks, while the outer limits of the range are tonalitic . The granite batholith is cut by dikes ; however, these are uncommon. Glaciers carved out the valleys during the late Pleistocene , which left a number of moraines . The series of moraines is formed by a series of glacial advances and retreats. Glacial till

216-730: The Blue Mountains, and it is known as the " Alps of Oregon". Much of the range is designated as the Eagle Cap Wilderness , part of the Wallowa–Whitman National Forest . The range is drained by the Wallowa River , which flows from the north side of the mountains, and its tributary the Minam River , which flows through the west side of the range. The Imnaha River flows from the east side of

243-485: The Cascades. At low elevations, Douglas fir is the most common tree for slopes, whereas Engelmann spruce and lodgepole pine occur in valley bottoms, with grand fir common below 5,300 feet (1,600 m). In meadows and around springs and seeps , willows and sedge grow. Above 7,000 feet (2,100 m), subalpine fir is dominant, and whitebark pine is often found on ridges and south-facing slopes. The area

270-524: The Columbia Plateau include: Idaho cities in the Columbia Plateau include: 45°59′58″N 119°00′05″W  /  45.99944°N 119.00139°W  / 45.99944; -119.00139 Mesic habitat In ecology , a mesic habitat is a type of habitat with a well-balanced or moderate supply of moisture throughout the growing season (e.g., a mesic forest, temperate hardwood forest , or dry-mesic prairie ). The term derives from

297-454: The Greek mesos , meaning middle, indicating its relative moisture content between hydric (moist) and xeric (dry) habitats. The word "mesic" can apply to the plants or soils within the mesic habitat (i.e. mesic plants, mesic soils). Mesic habitats provide a moderate moisture content that remains relatively constant during crucial growing periods. A variety of outside factors contribute to

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324-495: The North American plate is moving over it, creating a superb record of the rate and direction of plate motion. Part of the Columbia Plateau is associated with the Columbia Plateau ecoregion , part of the "Nearctic temperate and subtropical grasslands, savannas, and shrublands" ecoregion of the temperate grasslands, savannas, and shrublands biome . Washington cities in the Columbia Plateau include: Oregon cities in

351-493: The Sage Grouse Initiative under the U.S. Department of Agriculture to protect over 5.6 million acres of mesic habitat. The Working Lands for Wildlife organization has developed an interactive app to visualize mesic resources. The SGI Interactive Web App provides users with local conservation efforts across the entire range of sage grouse. Preservation of mesic habitats will promote stability and success within

378-472: The Yellowstone Plateau and that the farther west they went, the older the lavas. Although scientists are still gathering evidence, a probable explanation is that a hot spot , an extremely hot plume of deep mantle material, is rising to the surface beneath the Columbia Plateau Province. Beneath Hawaii and Iceland , a temperature instability develops (for reasons not yet well understood) at

405-484: The batholith and basalt flows. The Wallowa Batholith is formed of granite from a magma upwelling in Late Jurassic and Early Cretaceous time (between 160 million and 120 million years ago). The placement of this rock caused uplift of the surface, which at the time was tropical sea. This is evident from the slate , quartzite , and marble present in the mountains, which come from metamorphism of

432-482: The crust produced a large, slightly depressed lava plateau. The ancient Columbia River was forced into its present course by the northwesterly advancing lava. The lava, as it flowed over the area, first filled the stream valleys, forming dams that in turn caused impoundments or lakes. Entities found in these lake beds include fossil leaf impressions, petrified wood , fossil insects, and bones of vertebrate animals. Evidence suggests that some concentrated heat source

459-558: The ecosystem at hand. An important type of plant that reside within mesic habitats is the forb , which provides a strong source of food for many species, especially avian species such as the ruffed grouse . These habitats play an important role in the distribution abundance of sage grouse , influencing where they choose their breeding grounds, or leks . Mesic habitats are under stress from various human activities such as ranching, however many conservation efforts are underway. As of 2010, over 1,474 ranchers have agreed to partner with

486-595: The local avalanche center director, Kip Rand, was killed backcountry skiing near the Hurwal Divide and Chief Joseph Mountain in an avalanche following the collapse of a large cornice. The higher precipitation of the mountains compared with the surrounding country has created a mesic habitat in the Wallowas. Vegetation in the region contains combinations of plants found in both the Rocky Mountains and

513-420: The molten rock came to the surface, the Earth's crust gradually sank into the space left by the rising lava. The Columbia River Basalt Group consists of seven formations: The Steens Basalt, Imnaha Basalt , Grande Ronde Basalt, Picture Gorge Basalt, Prineville Basalt, Wanapum Basalt, and Saddle Mountains Basalt. Many of these formations are subdivided into formal and informal members and flows. The subsidence of

540-586: The mountains was built in 1861. In 1863, a new treaty was signed that relinquished lands that granted by an 1855 treaty, turning them over to the American government. This same year, the settlers in the mountains moved to present-day La Grande . These lands included the Wallowa Valley, home of Chief Joseph . The government first opened the Wallowa Valley to settlement in 1867. Surveyors began to come through and would continue until 1869. The Wallowa Valley

567-785: The presence of water in the system, including streams and their offshoots, wet meadows , springs, seeps , irrigated fields, and high-elevation habitats. These factors effectively provide drought insurance during the growing season against climatic factors such as increasing temperatures, lack of rain, and the effects of urbanization. Other habitat types, such as mesic hammocks , occupy the middle ground between bottomlands and sandhills or clay hills. These habitats can often be governed by oaks, hickories, and magnolias. However, there are some habitats that exhibit adaptations to fire. Natural Pinelands can persist in conjunction with mesic (moderately drained) or hydric but can also include mesic clay. Healthy mesic habitats can store large amounts of water given

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594-820: The range. The highest point in the range is Sacajawea Peak , which is 9,838 feet (2,999 m) above sea level . Sacajawea is the sixth highest mountain in Oregon and the state's highest peak outside of the Cascade Range . Many geologists believe that the Wallowa Mountains in northeastern Oregon are a displaced fragment of the Insular Belt . The core of the Wallowas is composed of the Wallowa Batholith surrounded by Columbia River basalt . In addition there are many older terranes between

621-415: The typical rich loamy soil composition and streams, springs, etc. This allows the entire habitat to essentially function like a sponge storing water in such a way that it can be deposited to neighboring habitats as needed. This supply helps to capture, store, and slowly release water. This supply aids in nutrient facilitation, bolstering community interactions. Mesic habitats are common in dryer regions of

648-436: The valleys it can be as low as 10 inches (250 mm). The Wallowa Mountains are a popular destination for backcountry skiers and snowmobilers. However, avalanches are a consistent threat to backcountry skiers and snowmobilers. In February 2014, two backcountry skiers were killed and two others were serious injured in the southern Wallowas on Cornucopia Peak when an avalanche swept into a mountainside gully. On 8 March 2016,

675-504: The western United States, such as the Great Basin , Great Plains , and the Rocky Mountains , where they serve as water sources for neighboring dry climates and desert habitats. Healthy mesic habitats can provide extensive benefits to surrounding communities and habitats for both biotic and abiotic factors. This boost in reserve water allows for ecological processes to commence and provide balance and nutrients for energy to flow through

702-622: Was home to the Wallowa band of the Lower Nez Perce . The Nez Perce lived in the canyons and burned trees to create meadows for the horses that they obtained around 1730. In 1834, Captain Bonneville crossed through the mountains and met with the lower Nez Perce on his way to Fort Walla Walla . In the 1840s, people began to move west, bringing settlers through the land. The Nez Perce began to trade with these settlers. A settlement in

729-461: Was partitioned in 1873, with one half for the Nez Perce and the other for settlers. Two years later, in 1875, the government banned the Nez Perce from the valley. The first road into the valley, a toll road , was constructed the same year. The U.S. Government attempted to force the removal of the Nez Perce in 1877; however, this angered the natives, who chose instead to raid the settlers, leading to

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