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UTAH

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Originally appearing in Volume V27, Page 819 of the 1911 Encyclopedia Britannica.
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UTAH,' one of the Central Western states of the United States of America. It lies between latitudes 370 and 42° N. and between longitudes 32° and 37° W. from Washington (i.e. about lo9° 1' 34" and 114° 1' 34" respectively W. of Greenwich). The state is bounded wholly by meridians and parallels, and is bordered on the N. by Idaho and Wyoming, on the E. by Wyoming and Colorado, on the S. by Arizona, and on the W. by Nevada. Utah has an area of 84,990 sq. m., of which 2806 sq. m. are water surface, including Great Salt, Utah and other lakes. The state has a maximum length of 345 M. N. and S., and a maximum width of about 28o m. E. and W. Physical Features.—The eastern portion of Utah consists of high plateaus, and constitutes a part of the Colorado Plateau province. The remaining western portion of the state is lower, belongs in the Great Basin province, and is characterized by north-south mountain ranges separated by desert basins. The high plateaus consist of great blocks of the earth's crust which are separated from each other by fault-lines, and which have been uplifted to different heights. Erosion has developed deep and sometimes broad valleys along the fault-lines and elsewhere, so that many of the blocks and portions of blocks are isolated from their neighbours. As a rule 1 The name is that of a Shoshonean Indian tribe, more commonly called Ute.813 the blocks have not been greatly tilted or deformed, but consist of nearly horizontal layers of sandstone, shales and limestone. In some cases these sedimentary rocks lie deeply buried under lavas poured out by volcanoes long extinct. The plateau summits rise to elevations of 9000, 10,000 and ii,000 ft., are generally forested, but are too difficult of access to be much inhabited. The people live along the streams in the valleys between the plateaus. In the southern part of the state the high plateaus are terminated by a series of giant terraces which descend to the general level of the Grand Canyon Platform in northern Arizona. The terraces represent the out-cropping edges of hard sandstone layers included in the series of plateau sediments, and are named according to the colour of the rock exposed in the south-facing escarpments, the Pink Cliffs (highest), White Cliffs and Vermilion Cliffs. A still lower terrace, terminating in the Shinarump Cliffs, is less conspicuous; but the higher ones afford magnificent scenery. The northernmost member of the high plateaus is a broad east-west trending arch known as the Uinta Mountains. Local glaciation has carved the higher levels of this range into a maze of amphitheatres containing lakes, separated from each other by aretes and alpine peaks. Among the peaks are King's Peaks (13,498 ft. and 13,496 ft.), the highest points in the state; Mt. Emmons (13,428 ft.); Gilbert Peak (13,422 ft.) ; Mt. Lovenia (13,250 ft.) ; and Tokewanna Peak (13,200 ft.). In the south-eastern part of the state are lower desert plateaus, and several mountain groups which do not properly belong to the plateau system. Most interesting among these are the Henry Mountains, formed by the intrusion of molten igneous rock between the layers of sediments, causing the overlying layers to arch up into dome mountains. Stream erosion has dissected these domes far enough to reveal the core of the igneous rock and to give a rugged topography. The highest peaks exceed x1,000 ft. By far the greater part of the high plateau district is drained by the Colorado river and its branches, the most important of which are the Green, Grand and San Juan, portions of whose courses lie in canyons of remarkable grandeur. The western members of the high plateaus drain into the Great Basin for the most part, and in this drainage system the Sevier river is perhaps most prominent. Inasmuch as the streams entering the basin have no outlet to the ocean, their waters disappear by evaporation, either directly from alluvial slopes over which they pass, or from saline lakes occupying depressions between the mountain ranges. The lower basin portion of Utah is separated from the high plateaus by a series of great fault scarps, by which one descends abruptly to a level of but 5000 or 6000 ft. One of the fault scarps is known as the Hurricane Ledge, and continues as a prominent landmark from a point south of the Grand Canyon in Arizona to the central part of Utah, where it is replaced by other scarps farther east. The floor of the Basin Region is formed of alluvium washed from the high plateaus and mountain ranges, a part of which has accumulated in alluvial fans, and part in the greatly expanded lakes which existed here in the glacial period. This alluvium gives gently sloping or level desert plains, from which isolated mountain ranges rise like islands from the sea. The barren " mud flats," frequently found on the desert floor, result from the drying up of temporary shallow lakes, or playas. Lake Bonneville is the name given to the most important of the much greater lakes of the glacial period, whose old shore-lines are plainly visible on many mountain slopes. Great Salt Lake (q.v.) is a shrunken remnant of Lake Bonneville. The mountain ranges of the Basin Region are most frequently formed by faulted and tilted blocks of the earth's crust, which have been carved by stream erosion into rugged shapes. Oquirrh, Tintic, Beaver, House and Mineral Mountains are typical examples of these north-south " basin ranges," which rise abruptly from the desert plains and are themselves partial deserts. The Wasatch Mountain range constitutes the eastern margin of the Great Basin in central and northern Utah, and resembles the true basin ranges in that it is formed by a great block of the earth's crust uptilted along a north-south fault-line. Its steep fault scarp faces west, and rises from 4000 to 6000 ft. above the basin floor; the eastern slope is more gentle, but both slopes are much scored by deep canyons, some of which have been modified in form by ancient glaciers. Among the highest summits are Timpanogos Peak (11,957 ft.), Mt. Nebo (11,887 ft.), Twin Peak (11,563 ft.), and Lone Peak (11,295 ft.). At the western base of the Wasatch are Salt Lake City, Ogden, Provo and other smaller towns, situated where streams issue from the mountains, soon to disappear on the desert plains. In such places agriculture is made possible by irrigation, and the Mormon villages, both here and farther south along the base of the Hurricane Ledge, depend largely on this industry. Important mining operations are carried on in the Wasatch Mountains and in a number of the basin ranges. Mercur, Tintic, Bingham and Park City are well-known mining centres. Fauna.—In the open country the mule deer, the pronghorn antelope and the coyote are found, and the bison formerly ranged over the north-eastern part of the state; the side-striped ground-squirrel, Townsend's spermophile, the desert pack-rat and the desert pack-rabbit inhabit the flat country. In the mountainous districts and high plateaus are the grizzly, formerly more common, the black bear, the four-striped chipmunk and the yellow-haired porcupine. Various species of small native mice and voles are abundant. In the marshes of the Salt Lake breed grebes, gulls and terns, and formerly the white pelican. Many ducks breed here, and many others pass through in migration: of the former, the most numerous are mallard and teal; of the latter, pintail, shoveler, scaup, ring-neck ducks, and mergansers. Wood and glossy ibises are commonly seen, and the white ibis breeds in numbers; the sand-hill crane is less common than formerly. A few varieties of shore birds breed here, as the Western willet, the Bartramian sandpiper, and the long-billed curlew. Gambel's partridge is resident in the southern part of the state, and the sage-hen and sharp-tail grouse on the plains. The dusky grouse and grey ruffed grouse are confined to the mountains and plateaus. The California vulture is very rare; various species of hawks and golden and bald eagles are common. The burrowing. owl is found on the plains, and various species of small birds are characteristic of the different physical divisions of the state. A few lizards are found in the arid districts. The trout of the Utah mountain streams is considered a distinct species. Flora.—Western Utah and vast areas along the Colorado river in the east and south-east are practically treeless. The lower plateaus and many of the basin ranges, as well as the basins them-selves, are deserts. The higher plateaus, the Uinta and Wasatch mountains, bear forests of fir, spruce and pine, and the lower slopes are dotted with pinon, juniper, and scrub cedar. On the slopes of mountain valleys grow cedars, dwarf maples and occasional oaks. Willows and cottonwoods grow along streams. The west slope of the Wasatch has been largely denuded of its forests to supply the demands of the towns at its base. Among other plants common to the state are the elder, wild hop, dwarf sunflower, and several species of greasewood and cacti. The sagebrush, artemisia, is characteristic of the desert areas. Bunch grass is abundant on the hillsides the year round, and affords valuable pasturage. Climate.—On account of its great diversity in topography, the state of Utah is characterized by a wide range in climatic conditions. Extremely cold weather may occur on the lofty plateaus and mountain ranges, while the intervening valleys and basins have a milder climate. The mean temperature of the state ranges from 58° in the extreme south to 42° in the north. Winter temperatures as low as 36° below zero are known for the higher altitudes; in the south, summer temperatures of 110° and higher have been recorded. At Salt Lake City the mean winter temperature is 31 °, the mean summer temperature 73°. Corresponding figures for St George, in the south-western part of the state, are 38 and 8o°. In general Utah may be said to have a true continental climate, although the presence of Great Salt Lake has a modifying effect on the climate of that portion of the Basin Region in which it lies. Killing frosts occur early in September and as late as the last of May, and in the higher valleys they may occur at any time. The mean annual precipitation is only I I in., the greater part of which occurs in the form of snow in the winter months, summer being the dry season. At Salt Lake City the annual precipitation is 15.8 in., of which 2 in. fall in summer. For St George the figures are: annual precipitation, 6.6 in.; summer, 1.3 in. Both Salt Lake City and St George are near the boundary between the Basin Region and the high plateaus. Well out in the basin deserts the precipitation is still less; and the same holds true for the low desert plateaus in the south-eastern part of the state, where Hite has an annual precipitation of only 2.3 in., of which 0.4 in. falls in the summer. On the other hand, the precipitation on the high plateaus probably exceeds 30 in. in places. In the inhabited parts of the state, irrigation is generally necessary for agriculture. Soil.—The alluvium of the desert basins furnishes much good soil, which produces abundant crops where irrigated. Alkali soils are also common in the basins, but when water is available they can often be washed out and made productive. Very rich floodplain soils occur along the larger streams. Vast areas of unreclaimable desert exist in the west and south-east. In the protected valleys between the high plateaus alluvial soils are cultivated; but the plateau summits are relatively inaccessible, and, being subject to summer frosts, are not cultivated. Comparatively poor, sandy soil is found on the lower desert plateaus in the south-east, where population is scanty. Forests.—The forest resources of Utah are of little value: the total wooded area was about 10,000 sq. m. in 1900, or about 121 % of the land area of the state. The only timber of commercial importance is found in the Uinta Range in the north-eastern corner of the state, and is chiefly yellow pine. The timber of the Wasatch Range is small and scattering. In 1910 there were in the state fourteen national forests varying in size from 1,250,610 acres (the Uinta reserve), 947,490 acres (the Ashley reserve), and 786,080 acres (the Manti reserve), down to the smallest Pocatello (10,720) on the Idaho border. The total area of these reserves was 7,436,327 acres. Irrigation.—Under the Federal Reclamation Fund, established in 1902, $830,000 was allotted to Utah in 1902-9, and $200,000 more in 1910, for the development of the Strawberry Valley project. This project, which was about one-third completed in the beginning of 1910, provides for the irrigation in Strawberry Valley (Utah and Wasatch counties, S. of Provo), of 6o,00o acres, by a 6800-acrereservoir of I10,000 acre-feet capacity, on Strawberry river; by a tunnel, 19,000 ft. long, connecting the reservoir with Diamond Fork, a tributary of Spanish Fork river; by a storage dam, 5o ft. high, of 6o,00o cub. yds. contents, diverting water from Spanish Fork river into two canals, one on each side of the river, for the irrigation of land in the valley of Utah lake ; by a hydro-electric power plant about 3 m. below the diversion dam ; and by the enlargement of existing canal systems. The diversion dam, the power canal, and the first unit of the power plant were completed in 1909. Irrigation of the arid western regions of the United States began in the Great Basin of Utah when the Mormon pioneers in 1847 diverted the waters of City Creek upon the parched soil of Salt End of Article: UTAH
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