Following the slope of the land, the important streams flow from N.W. to S.E. The Arkansas river enters the state from the N. near the 97th meridian, and after following a general south-easterly course, leaves it near the centre of the eastern boundary. Its tributaries from the N. and E.—the Verdigris, Grand or Neosho and Illinois—are small and unimportant; but from the S. and W. it receives the waters of much larger streams—the Salt Fork, the Cimarron and the Canadian, with its numerous tributaries. The extreme southern portion of the state is drained by the Red River, which forms the greater part of the southern boundary, and by its tributaries, the North Fork, the Washita and the Kiamichi.
Fauna and Flora.—Of wild animals the most characteristic are the black bear, puma, prairie wolf, timber wolf, fox, deer, antelope, squirrel, rabbit and prairie dog. Hawks and turkey buzzards are common types of the larger birds, and the wild turkey, prairie chicken and quail are the principal game birds. The total woodland area of the state was estimated in 1900 at 24,400 sq. m., or 34·8% of the land area. The most densely wooded section is the extreme E.; among the prairies of the W. timber is seldom found beyond the banks of streams. The most common trees are the various species of the oak and cedar. The pine is confined to the more mountainous sections of the E., and the black walnut is found among the river bottom lands. These four varieties are of commercial value. Other varieties, most of which are widely distributed, are the ash, pecan, cottonwood, sycamore, elm, maple, hickory, elder, gum, locust and river birch. The prairies are covered with valuable bunch, grama and dropseed grasses; in the extreme N.W. the cactus, sagebrush and yucca, types characteristic of more arid regions, are found.
Climate.—The climate of the state is of a continental type, with great annual variations of temperature and a rainfall which, though generally sufficient for the needs of vegetation, is considerably less than that of the Atlantic Coast or the Mississippi Valley. The western and central portions of the state are in general cooler and dryer than the E., on account of their greater elevation and greater distance from the Gulf Coast. Thus at Beaver, in the extreme N.W., the mean annual temperature is 57° F. and the mean annual rainfall 18·9 in.; while at Lehigh, in the S.E., these figures are respectively 62° and 35·1 in. At Oklahoma City, in the centre of the state, the mean annual temperature is 59°; the mean for the summer (June, July and August) is 78°, with an extreme recorded of 104°; the mean for the winter (December, January and February) is 38°, with an extreme recorded of −17°. At Mangum, in the S.W., the mean annual temperature is 61°; the mean for the summer is 81° and for the winter 41°, while the highest and lowest temperatures ever recorded are respectively 114° and −17°. The mean annual precipitation for the state is 31·7 in.; the variation between the E. and the W. being about 12 in.
Soils.—The prevailing type of soil is a deep dark-red loam, sometimes (especially in the east central part of the state) made up of a decomposed sandstone, and again (in the north central part) made up of shales and decomposed limestone. Not infrequently there are a belt of red sandy loam on uplands N. of a river, a rich deposit of black alluvium on valley bottom lands, a belt of red clay loam on uplands S. of a river, and a deposit of wind-blown loess on the water parting. Loess, often thin and always containing little humus, also covers large areas on the high, semi-arid plains in the western part of the state.
Agriculture and Stock-raising.—For some time before the first opening to settlement by white men in 1899, the territory now embraced in Oklahoma was largely occupied by great herds of cattle driven in from Texas, and since then, although the opening was piecemeal, the agricultural development has been remarkably rapid. By 1900, 22,988,339 acres, or 52·1%, of the total land surface was included in farms, and 8,574,187 acres, or 37·7%, of the farm land was improved.[1] The farm land was divided among 108,000 farms containing an average of 212·85 acres; 26,121 of them contained less than 50 acres, but the most usual size was 160 acres; and 48,983, or 45·35%, contained from 100 to 174 acres. A considerable portion of the larger farms (there were 2390 containing 500 acres or more) were owned by Indians but leased to white men. Much land as late as 1900 was held in common by Indian tribes, but has since been allotted to the members of those tribes and most of it is leased to whites. In 1900, 59,367 (or a little more than one-half of all) farms were worked by owners or part owners, 33,347 were worked by share tenants, and 13,903 were worked by cash tenants. Indian corn, wheat, cotton, oats and hay are the principal crops, but the variety of farm and garden produce is great, and includes Kafir corn, broom corn, barley, rye, buckwheat, flax, tobacco, beans, castor beans, peanuts, pecans, sorghum cane, sugar cane, and nearly all the fruits and vegetables common to the temperate zone; stock-raising, too, is a very important industry. Of the total acreage of all crops in 1900, 4,431,819 acres, or 68·64%, were of cereals; and of the cereal acreage 56·45% was of Indian corn, 34·45% was of wheat and 7·15% was of oats. The acreage of Indian corn increased from 2,501,945 acres in 1900 to 5,950,000 acres in 1909;[2] between 1899 and 1909 the yield increased from 68,949,300 bushels to 101,150,000 bushels. The acreage of wheat decreased during this period from 1,704,909 acres to 1,225,000 acres, and the yield from 20,328,300 bushels to 15,680,000 bushels. The acreage of oats increased from 317,076 acres to 550,000 acres, and the yield increased from 9,511,340 bushels to 15,950,000 bushels. The hay crop of 1899 was grown on 1,095,706 acres and amounted to 1,617,905 tons, but nearly one-half of this was made from wild grasses; since then the amounts of fodder obtained from alfalfa, Kafir corn, sorghum cane and timothy have much increased, and that obtained from wild grasses has decreased; in 1909 the acreage was 900,000 and the crop 810,000 tons. Except in the W. section, where there is good grazing but generally an insufficient rainfall for growing crops, cattle-raising on the range has in considerable measure given way to stock-raising on the farm, and nearly everywhere the quality of the cattle has been greatly improved. The total number of cattle decreased from 3,236,008 in 1900 to 1,992,000 in 1910, but at the same time the number of dairy cows increased from 276,539 to 355,000. The number of horses increased from 557,153 in 1900 to 804,000 in 1910; of mules from 117,562 to 191,000; of swine from 1,265,189 to 1,302,000; and of sheep from 88,741 to 108,000. Winter wheat is used extensively for pasturage during the winter months with little or no damage to the crop. No other branch of agriculture in Oklahoma has advanced so rapidly as the production of cotton; the culture of this fibre was introduced in 1890, and the acreage increased from 682,743 acres in 1899 to 2,037,000 acres in 1909, and the yield increased from 227,741 bales to 617,000 bales (in 1907 it was 862,383 bales). There was only a very small crop of broom corn in 1889, but in 1899 the crop was 3,565,510 ℔. The state has risen to high rank in the production of sorghum cane and castor beans also; in 1899 16,477 acres of the cane yielded 40,259 tons, and 14,070 acres of castor beans yielded 77,409 bushels. Two crops of potatoes may be grown on the same ground in one year, and the acreage of potatoes increased from 15,360 acres in 1899 to 27,000 acres in 1909, and the yield from 1,191,997 bushels to 1,890,000 bushels. Oklahoma is already producing large crops of apples, peaches, grapes, water-melons and musk-melons, and many large apple and peach orchards and vineyards have been planted. Pears, plums, apricots, cherries, strawberries, blackberries, raspberries, currants, gooseberries, cabbages, onions, sweet potatoes, tomatoes and cucumbers are grown in considerable quantities. The cereals and most of the fruits and vegetables are grown throughout the greater portion of the middle and E. parts of the state, although the soil of the N. middle section yields the best crops of wheat. Kafir corn and sorghum cane are the most common in the W. sections, where the climate is too dry for other crops. Some cotton is grown N. of the middle of the state, but the S.E. quarter takes in most of the cotton belt. Broom corn grows best in Woods county on the N. border, and castor beans in the central and N. central sections. About 3000 acres (nearly one-half in the narrow extension in the N.W.) were already irrigated in 1909, and surveys had been made by the Federal Reclamation Service with a view to irrigating about 100,000 acres more—10,000 to 14,000 acres in Beaver and Woodward counties, under the Cimarron project, and 80,000 to 100,000 acres in Kiowa and Comanche counties, under the Red River project.
Lumber and Timber Products.—The merchantable timber is mostly in that part of the state which formerly constituted Indian Territory, and consists largely of black walnut and other valuable hard woods in the bottom lands, of black jack and post oak on the uplands and of pine on the higher elevations S. of the Arkansas river. The manufactured forest products of Indian Territory increased in value from $189,373 in 1900 to $588,078 in 1905, or 205·78%.
Minerals.—The coal-fields extend from Kansas on the N. to Arkansas on the E., and have an area of about 20,000 sq. m. The principal mining centres are McAlester, Wilburton, Hartshorn, Coalgate and Phillips. In quality the coal varies from a low grade to a high grade bituminous, and some of the latter is good for coking. The output increased from 446,429 short tons in 1885 to 1,922,298 short tons in 1900, and to 2,948,116 short tons in 1908, the output for the last-named year being much less than for 1906 or 1907, when it was over 3,500,000 tons. The range of hills extending from the centre of the state N.W. to and beyond the Kansas border are composed chiefly of great deposits of rock gypsum. A similar but minor range extends parallel with it 40 to 50 m. S.W. There are also deposits in Greer county in the S.W. corner, and some gypsite in Kay county on the N. middle border. For working these extensive deposits there are, however, few mills; these are in Kay, Canadian and Blaine counties. Some petroleum was discovered in the N. part of Indian Territory near the Oklahoma border as early as 1890, but there was little development until 1903, when several wells were drilled in the vicinity of Bartlesville. Then wells were drilled to the W. on the Osage Reservation, and to the S., until in 1906 about 110 wells were drilled into the famous Glen Pool near Sapulpa. One of these wells has a flow of about 1000 barrels a day, and the total product from the Oklahoma oil-field (which includes wells in
