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North Dakota The Geography
Located at the geographical center of the North American continent, North Dakota is bounded on the north by the 49th parallel, which separates it from the Canadian provinces of Manitoba and Saskatchewan. Its eastern boundary, the only natural boundary of the state, consists of the Red River of the North, or Red River, and one of its headwater streams, the Bois de Sioux River. North Dakota’s boundaries enclose a rectangular area of 183,112 sq km (70,700 sq mi), including 4,465 sq km (1,724 sq mi) of inland water, making it the 18th largest state in the nation. From north to south its maximum distance is 341 km (212 mi), and from east to west, North Dakota extends for 581 km (361 mi). The state slopes downward from southwest to northeast. The lowest point, 229 m (750 ft) above sea level, is found at the Red River near Pembina, in the northeastern corner of the state. The state’s highest point, 1,069 m (3,506 ft), is White Butte, in southwestern North Dakota. The mean elevation of the state is about 580 m (1,900 ft).
North Dakota is a Plains state. Although it is largely flat or rolling, there are rough and hilly sections. In relatively recent geologic time a continental glacier spread over all but the southwestern section. It brought soil from Canada, scoured down the highlands, and filled in the lowlands. The glacier blocked the northward-flowing Red River, forming the glacial Lake Agassiz, whose dry lake basin forms the flat and fertile Red River valley in the east.
Natural Regions
Two major physiographic provinces, or natural regions, are represented in North Dakota. These are the Central Lowland and the Great Plains, both subdivisions of the Interior Plains. Eastern North Dakota belongs to the Western Lake section of the Central Lowland. The low plains around the Red River are the remains of the lake basin of Lake Agassiz. West of the old lake basin the terrain rises a little and is known as a drift plain because of the drift, or finely ground rock and gravel, left by the glacier. In the northern part of the state the Pembina escarpment separates the Red River valley and the drift plain and is especially noticeable in the Pembina Mountains. In Canada the escarpment is called the Manitoba escarpment. The remainder of the Red River valley is separated by several successive beaches laid down by the retreating glacial Lake Agassiz. Another feature of the Central Lowland in North Dakota is the Turtle Mountains. Straddling the North Dakota-Manitoba border, these mountains, which resemble a mesa 760 m (2,500 ft) in elevation, present an interesting contrast to the plains because they are forested. Marking the division between the Central Lowland on the east and the Great Plains on the west is a section called the Coteau du Missouri, or “hills of the Missouri,” which is part of the glaciated section of the Missouri Plateau. The coteau, up to 40 km (25 mi) wide, consists of moraine, or boulders and rocks left by the glacier. The glacial moraine of the Coteau du Missouri appears in a series of hummocks and hills 30 to 40 m (100 to 150 ft) high. The coteau runs roughly parallel to the Missouri River in a long diagonal belt through the state.
The glaciated portion of the Missouri Plateau is mostly a subdued rolling prairie. The Missouri River has cut a channel from 120 to 150 m (400 to 500 ft) deep, and the stream bed between the bluffs is as much as 5 km (3 mi) wide in some places. Many old lake basins are seen in this plateau area, and here and there isolated mountains rise above the surface of the land. An example is the Killdeer Mountains in west central North Dakota. These sandstone-capped buttes are remnants of the landscape prior to the wind and water erosion and rise about 180 m (about 600 ft) above the surrounding countryside.
The unglaciated section of the Missouri Plateau in the southwestern corner of North Dakota is distinct from the other parts of the state chiefly because its surface features have not been affected by glaciation. This section contains White Butte, the highest elevation in the state, Sentinel Butte, Black Butte, Bullion Butte, the Killdeer Mountains, and the Badlands. They were so named by early travelers who found them bad lands to travel through. North Dakota’s Badlands are only one of several such areas in which erosion near rivers has cut down the land surrounding the river systems, leaving small buttes or peaks surrounded by deep gullies and ravines. Badlands topography is seen in dry areas where vegetation has not grown up to prevent such erosion, especially when sudden torrential rains occur. Usually in such areas the surface material is soft and easily cut away. In the Badlands of North Dakota slow-burning beds of lignite coal have melted adjoining clay beds into colorful masses called clinker. The Badlands follow much of the Little Missouri River to the point where it empties into the Missouri River.
Rivers and Lakes
The Missouri River, which flows south into the Mississippi River, and the Red River of the North, which flows north into Lake Winnipeg and ultimately into Hudson Bay, drain North Dakota. The principal tributaries of the Missouri in North Dakota are the Cannonball, Heart, James, Knife, and Little Missouri rivers. Tributaries of the Red that flow through North Dakota include the Sheyenne, Goose, Park, Pembina, and Souris rivers.
Many small lakes dot the glaciated portion of North Dakota. Devils Lake is the largest natural lake in the state. Its waters are salty because it lacks an outlet. There are also many artificial lakes. The largest, Lake Sakakawea, is a reservoir on the Missouri River north of Bismarck and is one of the largest lakes in the United States, covering 1,458 sq km (563 sq mi). Other important reservoirs include Arrowhead, Darling, and Heart Butte. Lake Oahe, also a reservoir on the Missouri, is shared between North and South Dakota.
Climate
North Dakota has hot summers and long cold winters. Its maximum precipitation falls in spring and early summer. Weather conditions, including temperature, can change rapidly. Mean temperatures in Bismarck, near the center of the state, are representative of those of most parts of the state. January, the coldest month, has an average temperature of -13° C (9° F), and July, the warmest month, averages 21° C (70° F). Extremes of 49° C (121° F) and -51° C (-60° F) have been recorded. At Bismarck, the growing season averages 134 days, as the average date of the last killing frost is May 11 and that of the first killing frost is September 22. The length of the growing season drops to about 110 days in the northerly reaches of the state. The long periods of summer sunshine at this latitude, providing as much as 16 hours of daylight in summer, help crops to mature quickly, thus compensating somewhat for the relatively short growing season.
Temperatures in the north are, on the average, several degrees lower than those in the south. Some of the greatest variations are from west to east. The west is affected by Chinook winds while the east is not. Average January temperatures range from -10° C (14° F) in the west to -16° C (3° F) in the east. The range for precipitation is also greater from east to west. Precipitation ranges from 510 mm (20 in) in the east to 360 mm (14 in) in the west. Snowfall is relatively light, although low temperatures keep the snow from melting and strong winter winds can cause enormous snowdrifts. Most of the precipitation falls during the growing season and therefore benefits farming. The precipitation averages are about the minimum needed for farming, and at times dry years have caused crop disasters.
Soils
The most valuable natural resource of North Dakota is its deep, dark, and rich soil. Developed under grass, this soil is among the best in the world and is capable of great agricultural production. Most of the soil is a loam, clay or a silt loam. The soils of the eastern part of the state, classified as udic haploborolls, are darker, deeper, and more productive than the chestnut-brown soils of the unglaciated Missouri Plateau.
Plant Life
North Dakota belongs to the grasslands that extend from the Rocky Mountains to the forests of eastern North America. Tall prairie grasses predominate in the east, especially the Red River valley, but short steppe grasses are dominant in the west. The central part of the state is a transitional zone of mixed tall, mid, and short prairie grasses. Most of the grasslands have been plowed for crops, but there are still about 6 million hectares (about 15 million acres) of grass in the state, most of it native prairie grass. In draws or hollows scattered brushes or shrubs are found, usually consisting of one or several varieties of chokecherries, Juneberries, wild plums, hawthorns, raspberries, buckbrushes, and wild roses. The wild prairie rose is the state flower.
North Dakota is a grassland state, and native forests amount to only 1.5 percent of its land area. Most of the forests are found in the Turtle Mountains, the Pembina Gorge region, the Missouri, Sheyenne, and Pembina river valleys, and around Devils Lake. The principal trees are the green ash, elm, quaking aspen, birch, oak, and cottonwood. In the western part of the state, ponderosa pines and cedars (junipers) are found. Most forestry activities in North Dakota are focused on planting. Both state and federal agencies participate in planting programs to establish shelterbelts and windbreaks to prevent wind from blowing away precious topsoil.
Animal Life
The great herds of bison that once roamed freely on the North Dakota prairie can now be seen in wildlife refuges and national park units. Elk and moose can be found in the forest areas between the Turtle Mountains and Pembina Gorge in the northeast, while elk also can be found in the Badlands, where wild horses also run. White-tailed deer are abundant throughout the state, and mule deer and antelope abound in the western part. Bighorn roam the Badlands, and the howl of the coyote can be heard at night. Rabbits, foxes, and squirrels are common. Mink, muskrat, skunks, beaver, weasels, and an occasional raccoon also inhabit the state, and prairie dog colonies can still be found.
Birds are abundant. There are sage hens, sharp-tailed grouse, plover, and ruffed grouse, as well as ducks, geese, pelicans, gulls, grebes, and other water birds. There are also many hawks, owls, and eagles. The Souris Loop refuges contain almost 300 species of birds. The ring-necked pheasant, wild turkey, chukar, and Hungarian partridge have been brought into the state. Among the fishes that live in the waters of the state are pike, saugers, trout, salmon, walleyes, and muskellunge.
Conservation
Conservation of natural resources has become a major consideration in North Dakota. The state soil conservation committee, the state game and fish department, and the state water commission work with federal agencies to conserve the state’s natural resources.
Since the 1930s, the time of the Dust Bowl in the United States, prevention of soil erosion has been of special concern in the state. Many farmers have put conservation practices into effect. All of the state’s land area is included in soil conservation districts.
Hundreds of dams have been constructed in the state for flood control, municipal water supply, and irrigation. The largest is Garrison Dam on the Missouri River. Other important dams are Baldhill Dam, on the Sheyenne River; Homme Dam, on the Park River; Dickinson and Heart Butte dams, on the Heart River; Bowman-Haley Dam, on the Grand River; and Jamestown Dam, on the James River.
All of North Dakota’s coal production comes from strip mining, in which the soil and rock above the coal is stripped off by excavating machines. The land in a strip-mined area is devastated, but it can be reclaimed or restored for farming, grazing, or other productive uses. A state law requires the reclamation of land in strip-mined areas.
North Dakota does not have any significant urban or industrial pollution. However, the many irrigation and water diversion projects in the state have caused concern over possible pesticide and sediment runoff, and the major Garrison Diversion Project in western North Dakota was halted in the late 1970s after it was determined that agricultural runoff might disturb the ecology of the Souris River. |
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