II.

Physical Geography

Kansas ranks 15th among the states in size. It has a total area of 213,096 sq km (82,277 sq mi), including 1,197 sq km (462 sq mi) of inland water. The state is rectangular in shape, except for a small section in the northeast where it is bounded by the Missouri River. It measures 661 km (411 mi) from east to west and 335 km (208 mi) from north to south.

The surface of Kansas can, in a very broad sense, be described as a plain. However, it is neither entirely flat nor entirely level, and minor variations in relief are conspicuous. The state’s surface elevation increases gradually from east to west, rising from a minimum elevation of 207 m (679 ft) above sea level in the Verdigris River valley to 1,231 m (4,039 ft) at Mount Sunflower, the highest point in the state. The approximate mean elevation is 610 m (2,000 ft). Hills, ridges, and wooded river valleys abound in eastern and central Kansas. Farther west they give way to the flatter, generally treeless High Plains, which are frequently but inaccurately thought of as characteristic of the entire state.

A.

Natural Regions

Kansas includes parts of two physiographic provinces, or natural regions, of the United States, the Central Lowland and the Great Plains. Together these two natural regions constitute part of the major physiographic division of North America known as the Interior Plains. In addition, a small area in extreme southeastern Kansas is part of the Ozark Plateau physiographic province.

The Central Lowland covers the eastern third of the state. It can be divided into two sections, the Dissected Till Plains and the Osage Plains. The Dissected Till Plains occupy the northeastern corner of the state. This section differs in appearance from the rest of the Central Lowland in Kansas. The only part of the state that was glaciated during the Ice Age, which ended about 10,000 years ago, it exhibits the gently rolling hills, broad shallow valleys, boulder-strewn plains, and other landforms characteristic of glaciated plains. It more closely resembles the typical prairie areas of Iowa and other Midwestern states than do the other sections of Kansas. The Osage Plains section is an area of varied relief, with flat or gently rolling plains broken by a series of low, linear ridges that trend north-south. The most prominent of these ridges are the Flint Hills, which lie just east of the 97th meridian and extend from the Kansas River southward into Oklahoma. The Flint Hills, which rise more than 120 m (400 ft) above the surrounding plains, are composed primarily of limestone but derive their name from a form of chert commonly called flint that is scattered over their surface.

The Great Plains cover the central and western portions of the state. This region can be divided into two sections, the Plains Border and the High Plains. The Plains Border, which forms a transitional zone between the Central Lowland and the High Plains, includes several broad belts of hills. North of the Arkansas River they include the Smoky Hills and the Blue Hills. South of the river, in the great loop between Wichita and Dodge City, lies a broad plains area that forms, in effect, an eastward extension of the High Plains. Much of this region is quite sandy. The sand plain is bounded on the south by the Gypsum Hills, or Cimarron Breaks, a scenic area of mesas and buttes that are composed of red shale capped with gypsum. The High Plains section is a dry, gently rolling tableland. Some of the section’s most prominent physical features are found where the rivers, especially those of the northwest, have cut valleys well below the general surface, creating steep-sided bluffs. Throughout the High Plains section are numerous shallow saucerlike depressions. Some of these are products of wind erosion. Others have been formed by the sinking of the land, which has been caused by the action of underground water on soluble rocks.

A number of unusual geologic formations in Kansas occur on the Great Plains, an area that is also noted for its abundant fossils. In Gove County, Monument Rocks, also called the Kansas Pyramids, rise abruptly above the valley of the Smoky Hill River. Sculpted by wind and water, they represent the remnants of shale and chalk that, eons ago, covered what is now the Smoky Hill Valley. Castle Rock, in Gove County east of the Monument Rocks, is the most prominent of these formations, standing 21 m (70 ft) high. About 30 km (about 20 mi) north of Salina lies Rock City, an area of more than 200 eroded sandstone concretions that resemble huge eggs.

B.

Rivers and Lakes

Kansas lies within the drainage basin of the Mississippi-Missouri river system. The chief streams in the state are the Kansas River (sometimes called the Kaw) which is a tributary of the Missouri River, and the Arkansas River, which is a major tributary of the Mississippi.

The Kansas River, together with its headstreams and tributaries, drains most of the northern half of the state and flows generally eastward to enter the Missouri River at the adjoining cities of Kansas City, Kansas, and Kansas City, Missouri. Its chief headstreams are the Republican and Smoky Hill rivers, which join to form the Kansas River at Junction City. Each of the headstreams has numerous tributaries. The Kansas River proper is only 270 km (170 mi) long, but the Smoky Hill River has a length of 870 km (540 mi), and the Republican River has a length of 720 km (450 mi). The main tributary flowing into the Kansas River is the Big Blue River.

The Arkansas River, which rises in Colorado, flows generally eastward and then southward across the southern half of Kansas. Between Dodge City and Wichita the river curves northward in a wide loop, which is known as the Great Bend of the Arkansas River. A small section of the Cimarron River, a major tributary of the Arkansas, arcs through the southwestern corner of the state. Southeastern Kansas is drained mainly by the Verdigris and Neosho, which flow southward to join the Arkansas River in Oklahoma.

There are no large natural lakes in Kansas. The largest bodies of water have been created by the damming of rivers. The largest is Tuttle Creek Lake, a long winding reservoir behind Tuttle Creek Dam on the Big Blue River. Other major bodies of water include Cedar Bluff and Kanopolis on the Smoky Hill River; Milford on the Republican; Lovewell on White Rock Creek and Keith Sebelius on Prairie Dog Creek, both tributaries of the Republican; Wilson on the Saline River; Cheney on the North Fork of the Ninnescah; John Redmond and Council Grove on the Neosho; Toronto on the Verdigris; Waconda on the Solomon, and Webster and Kirwin on the forks of the Solomon; Perry on the Delaware; Clinton on the Wakarusa; Marion on the Cottonwood; Pomona, Melvern, and Hillsdale on the Marais des Cygnes system; and Fall River Lake, a reservoir on the river of that name.

C.

Climate

The climate of Kansas is warm to hot during summer and cool to cold in winter. Although there is a large difference between summer and winter temperatures, during each season of the year temperatures do not vary greatly from place to place. In winter the prevailing winds are from the north. In summer they are from the south or southwest.

C.1.

Temperature

Average January temperatures range from about 1° C (about 34° F) in the southeastern part of the state to between -3° and -2° C (26° and 28° F) in northern Kansas. The average January temperature at Topeka is about -2° C (about 28° F). Throughout the state, daytime lows in the lower -20°s C (below 0° F) sometimes occur in winter, and lows of -34° C (-30° F), although infrequent, have been recorded.

Average July temperatures range from below 24° C (76° F) in northwestern Kansas to above 27° C (80° F) in sections of central and southern Kansas. The average July temperature at Topeka is about 26° C (about 78° F). Throughout the state, daytime highs are often in the lower 30°s C (lower 90°s F), and extreme summer temperatures in the lower 40°s C (upper 100°s F) have been recorded in most areas.

C.2.

Precipitation

Precipitation (rainfall and snowfall) diminishes from east to west, ranging from between 860 and 1,020 mm (34 and 40 in) in the east to between 410 and 510 mm (16 and 20 in) in the west. The eastern third of Kansas, the wettest part of the state, usually receives more than 760 mm (30 in) of precipitation. However, precipitation is extremely variable from year to year and, to a lesser extent, from place to place. In each decade, cycles of comparatively wet years alternate with cycles of dry years. In dry years drought conditions vary in severity and extent, but they are more common in the western part of the state than elsewhere. During the most severe droughts the combination of hot rainless days and high winds create dust-bowl conditions in western Kansas and in other parts of the Great Plains.

Most of the annual precipitation in Kansas falls as rain, occurring mainly during the period from April through August, when it is most needed for growing crops. However, it is often in the form of heavy thundershowers or hailstorms, which can damage crops. In winter, precipitation is generally light and usually in the form of snow. Blizzard conditions occur when the snow is accompanied by strong winds. Tornadoes, which are violent windstorms, occur with some regularity in Kansas, usually in the spring.

C.3.

Growing Season

The growing season, or period between the last killing frost in the spring and the first killing frost in the fall, ranges from about 160 days in the northwest to more than 190 days in the south and southeast. In the spring the last killing frost usually occurs in the first two weeks of April in the southeast and in the last week of April in the northwest. The fall killing frost usually occurs in the first week of October in the northwest and in middle or late October in the southeast.

D.

Soils

Almost all of the soils in Kansas are called mollisols. They generally are fertile, but their productivity varies considerably, usually in proportion to the amount of water they receive.

Udolls, one type of mollisol, cover large areas of eastern Kansas, which is the wettest part of the state. In these areas, especially in the Dissected Till Plains section, field crops are raised on the deep productive loams. In the Flint Hills section, however, fragments of flint in the soil make cultivation difficult. Much of this area is better utilized as grazing land. The dark-brown udolls of the Osage Plains in southeastern Kansas often contain a faint reddish tint caused by oxidized iron. Relatively high precipitation in this area has leached more plant nutrients from these soils than is the case elsewhere in the state. This leaching must be counteracted by fertilizer if farmers hope to produce good crops.

A second type of mollisol, called ustoll, is characteristic of Kansas west of the Flint Hills. These, too, are fertile soils. Ustolls are slightly lighter in color than the udolls and contain more carbonate. These loams are well suited for the cultivation of wheat and are highly productive in years of adequate precipitation.

In extreme western Kansas the ustolls become lighter still in color and contain even more carbonate. These soils, which cover the driest areas of the state, are not usually highly productive. In times of drought they have been subject to wind erosion and the consequent loss of topsoil.

E.

Plant Life

Forests in Kansas cover only 3 percent of the state. Much of the woodland is found along river and stream valleys, and tree growth is heaviest in the eastern part of the state. In addition, trees have been planted throughout the state as windbreaks.

Among the most common trees of eastern Kansas are the cottonwood, which is the state tree, species of oak, hickory, and elm, and black walnut, sycamore, box elder, green ash, and hackberry. Cottonwood, willow, and red cedar are the principal trees in western Kansas. The Osage orange is found in hedgerows in some areas of the state. The red cedar is the only conifer native to Kansas.

Before the middle of the 19th century grasslands covered most of Kansas. In the tallgrass prairie grasslands of the east the most common grasses were big bluestem, little bluestem, switchgrass, and Indian grass. In the dry shortgrass prairie of the west grew buffalo grass, blue grama, and little bluestem. Central Kansas was a transitional zone where tall and short grasses were mixed. During the second half of the 19th century much of the state’s vast grassland area was ploughed over as cultivation was extended throughout the state. The largest remnant is in the Flint Hills.

Kansas still has a great variety and abundance of wildflowers. The helianthus, or wild native sunflower, is the state flower. Other common wild flowers include the aster, prairie phlox, goldenrod, gayfeather, primrose, verbena, daisy, clover, and thistle. Tumbleweed, a characteristic plant of the High Plains, occurs in western Kansas, and the prickly pear and yucca are most abundant in the driest parts of the area.

More than 1,800 species of flowering plants, conifers, and ferns occur in Kansas. Nearly 500 species have been introduced from Europe, Asia, and other parts of the world.

F.

Animal Life

In the mid-19th century, Kansas still had varied and abundant wildlife, including numerous large game animals. Huge herds of American bison, commonly called buffalo, roamed the open plains. There were also whitetailed deer, elk (or wapiti), and antelope, and wild horses that were descendants of stock brought to America by early Spanish explorers. In the woodlands of the east were black bears, cougars, gray wolves, and other, smaller mammals. By the end of the 19th century, indiscriminate hunting and changes in the natural habitat had resulted in the near extinction of all the large mammals except for deer. Today, small herds of buffalo and elk are preserved in wildlife management areas and private ranches. Small mammals include the coyote, red fox, badger, blacktailed prairie dog, weasel, woodchuck, raccoon, opossum, striped skunk, fox squirrel, jack rabbit, and cottontail.

Many species of birds, including resident and migrant species, are found in Kansas. Year-round residents include the cardinal, robin, bluejay, Carolina wren, several species of woodpecker, eastern meadowlark, and western meadowlark, which is the official state bird. Among the summer residents are the barn swallow, ruby-throated hummingbird, catbird, and brown thrasher. Winter residents include the longspur, slate-colored junco, and tree sparrow. Among the many migrant birds that pass through the state are several species of hawks, warblers, sparrows, and waterbirds. Bald eagles are recovering in numbers in the state. The most common game birds, which include resident and migrant species, are the ring-necked pheasant, bobwhite, wild turkey, prairie chicken, mallard, and canvasback.

There are numerous reptiles, especially in the dry western sections. Poisonous snakes include the copperhead and three species of rattlesnake. Among the nonpoisonous snakes are the coachwhip snake, the blue racer, the bull snake, and the prairie king snake. Lizards common in the state include the horned toad, the six-lined racerunner, and several species of skink. Fish in the rivers and lakes of Kansas include several varieties of catfish, and the crappie, carp, walleye, black bass, and bluegill.

G.

Conservation

The three major conservation goals in Kansas are soil conservation, flood control, and protection of the state’s native plant and animal life. Federal agencies active in conservation include the Natural Resources Conservation Service, the Fish and Wildlife Service, the Forestry Service, the Bureau of Reclamation, and the United States Army Corps of Engineers. State agencies involved in conservation include a forestry, fish and game commission, a water resources board, a conservation commission, and a park and resources authority.

Soil erosion has damaged extensive areas of farmland in Kansas. The most severe damage has occurred in the central and western parts of the state, where in some places as much as 75 percent of the topsoil has been stripped off by erosion. Much of the damage occurred during the prolonged drought of the 1930s, the notorious Dust Bowl years on the Great Plains. During those years, wheatlands left fallow and over-grazed grasslands with little grass cover were exposed to the forces of erosion. High winds picked up the loose topsoil and carried it away in great swirling dust storms. Since the 1930s the widespread adoption of improved farming techniques has helped prevent further serious soil losses. Wind and water erosion have been reduced by terracing and the planting of wind barriers. Farm ponds help to control water runoff.

The statewide soil conservation programs have also helped to reduce springtime flooding caused by runoff. However, the principal flood-control programs are those regulating the flow of water in the rivers of the state. The programs are integrated with those of adjoining states and are often part of multiple-purpose projects that include provisions for flood control, irrigation, hydroelectric power generation, and recreation. The largest of these federally organized projects is the Missouri River Basin Project, which includes flood-control dams and storage reservoirs on the Republican and Smoky Hill rivers as well as on some of their tributaries.

A major environmental problem is runoff from agricultural land, which is carrying agricultural chemicals into drinking water. In 2006 the state had 10 hazardous waste sites on a national priority list for cleanup due to their severity or proximity to people. Between 1995 and 2000, the amount of toxic chemicals discharged into the environment remained stable, changing by less than half a percent.