grassland and desert animals is of special interest. 

 We see it expressed in jack rabbits, kangaroo rats, 

 pocket mice, and grasshoppers in North America ; all 

 these species have short forelegs and long, strong, 

 hind ones. Hopping enables the animals to get above 

 the level of the grass for locomotion and is of advan- 

 tage also in allowing greater visibility. 



There is a nearly complete absence of animals 

 above ground in the winter. Bison formerly shifted 

 their main populations from the northern to the 

 southern portions of the grassland, pronghorns sought 

 shelter in the piiion- juniper woodlands and petran 

 bush in the valleys and foothills of the mountains, and 

 most of the birds left for the South. Ground squir- 

 rels, prairie dogs, and jumping mice hibernate in 

 underground burrows, reptiles from over large areas 

 aggregate into deep holes or crevices in the sides of 

 hills, and invertebrates pass the winter in a dormant 

 or inactive condition in the soil humus. Many of 

 these animals also become inactive or aestivate dur- 

 ing dry seasons, especially in late summer and 

 autumn, and sometimes aestivation proceeds directly 

 into hibernation so that the animals are active for 

 only a short time each year. 



Grassland birds are direct, strong fliers and can 

 withstand the fierce winds prevalent in open country. 

 They are adroit in walking and running on the 

 ground. They also appear better able to tolerate the 

 continuous direct rays of the sun, but nevertheless 

 on hot sunny days they commonly seek the shade of 

 the tall grasses, scattered bushes, or line up in the 

 narrow shadow of a fence post or telephone pole. 

 With the absence of trees, many birds make them- 

 selves conspicuous during the nesting season by de- 

 veloping loud flight songs which they give high in the 

 air. Flight songs are much more characteristic of 

 grassland than of forest birds. Contrary to the herd 

 instinct in mammals, flocking is not particularly char- 

 acteristic of grassland birds, although prairie chickens 

 and grouse exhibit gregariousness in their mating 

 performances. Birds are usually widely spaced with 

 their nests well concealed in the grass (Kendeigh 

 1941a). 



The more humid portion of the grassland is 

 studded with small ponds or potholes. These ponds 

 are surrounded with marsh vegetation. Here are 

 found numerous ducks, grebes, herons, bitterns, 

 coots, rails, terns, and other marsh birds as well as 

 muskrats. Animal life is especially concentrated 

 around these water holes (Brehm 1896), although 

 larger species roam widely through the upland for 

 feeding purposes. 



HUMAN RELATIONS 



Tall grass prairie is highly productive agri- 

 cultural land for corn, wheat, soybeans, and cereal 



crops in general. This is evident both in North 

 America and Europe. Hogs are raised on the corn 

 that is grown. The more arid short grasslands, such 

 as are found on the Great Plains and the northern 

 Great Basin of North America and on the Russian 

 steppe, are more hazardous to cultivate, as crops, 

 mostly wheat, often fail during the dry years of cli- 

 matic cycles. Plowed or overgrazed ground, destitute 

 of grass or crop cover, is whipped up by strong winds 

 to produce the great dust storms that have become 

 so well known in recent years. Dry farming for wheat 

 is a common practice in some areas, where land is 

 cropped only every two or more years and left idle 

 between times to accumulate ground moisture, or 

 there may be crop production under irrigation 

 (Weaver 1927). Man has not always used grassland 

 intelligently (Shelford 1944) especially during the 

 war years when the demand for food supplies was so 

 great, because he has plowed up land where the grass 

 cover should have been left intact. Arid grassland 

 in the Great Plains had best be used only for stock 

 raising, especially of beef cattle and sheep, and this is 

 done extensively on our western ranches. In the arid 

 parts of Asia, many different peoples have a nomadic 

 existence in a never-ending search of pasture for the 

 cattle, sheep, goats, camels, and horses that serve 

 their everyday needs (Hadlow 1953). 



The history of early exploration and settlement on 

 the North American grassland is of considerable in- 

 terest (Malin 1947). Before the advent of white 

 man, Indians were scarce over the grassland because 

 of difficulties in transportation and in hunting large 

 game animals. With the escape of horses from the 

 early Spaniards and their rapid multiplication, the 

 Indians soon learned to use them, and several tribes 

 took to the prairies and plains. 



The white man was, at first, somewhat reticent 

 about invading the prairies and kept his settlements 

 to the forested areas along the streams. The prairies 

 that he first encountered along the forest-edge in the 

 East were flat, very wet in the spring, and poorly 

 drained. The grass roots made a tough sod difficult 

 to plow with the primitive equipment then available. 

 There were difficulties in obtaining drinking water. 

 Prairie flies were a nuisance, and the prairie fires that 

 occasionally swept across the country were danger- 

 ous. Furthermore, he was accustomed to using tim- 

 ber for buildings, fences, and fuel, and the forest 

 gave him protection from cold winter winds (Vestal 

 1939). In the course of time, however, and under the 

 pressure of increasing populations, he learned to sur- 

 mount these difficulties. Ditches were dug to drain 

 the land and the streams were deepened. Better 

 plows and other farm equipment made cultivation 

 easier. Construction of roads, bridges, and railroads 

 brought building equipment for homes, supplies, and 

 other comforts of life. At the present time the tall 



330 Geographic distribution of communities 



