10 CULTIVATED FORAGE CROPS OF THE NORTHWEST. 
GREAT PLAINS. 
This region extends from about the ninety-eighth meridian to the 
Rocky Mountains and from Texas far north into Canada. The altitude 
increases from about 1,500 feet, at the eastern limit, to the base of 
the mountains, where it may be 6,000 or 7,000 feet. The western 
portion of this area extends into the group of States considered in 
this bulletin. The topographical features of this region are discussed 
by the late Thomas A. Williams in Bulletin No. 12 of the Division 
of Agrostology, U.S. Department of Agriculture, entitled ‘‘A Report 
upon the Grasses and Forage Plants and Forage Conditions of the 
Eastern Rocky Mountain Region.” 
The annual rainfall is usually from 10 to 12 inches, in consequence 
of which the cultivation of crops is dependent upon irrigation. The 
native grasses are well adapted to grazing, and hence stock raising is 
the paramount industry throughout this portion of the Great Plains, 
which includes the eastern part of the States of Montana, Wyoming, 
and Colorado. ‘The stock raised is chiefly cattle and sheep, vast herds 
of which roam over the plains during the summer, and, in most local- 
ities, for the greater part of the winter, subsisting upon the short 
grasses, the most important of which are buffalo grass (Lulbilis dacty- 
loides) and blue grama (Louteloua oligostachya). Along the draws or 
in the valleys of the streams taller grasses occur, such as blue-stem 
(Andropogon furcatus) and alkali saccaton (Sporobolus airoides), the 
common bunch grass of the Arkansas Valley. The upland or ‘‘ short” 
grasses seldom grow sufficiently tall for hay, but in favorable seasons 
hay is cut in those situations where the tall grasses abound. The - 
foliage of the short grasses usually cures on the ground and furnishes 
food through the winter; but in order to provide food during the 
stormy periods of the winter and to increase the carrying capacity © 
of the ranges by supplementing the natural food supply, hay is put — 
up for winter use. This practice is increasing as competition enforces 
more economical methods of agriculture. Almostall the forage stored 
for winter is produced by the aid of irrigation. Near the base of the 
mountains there is an abundant supply of water in the mountain streams, 
and this is distributed along the valleys by means of canals. In many 
places storage reservoirs supply water in the canals during a portion 
of the period of low water. 
The most important forage plant raised by cultivation is alfalfa. 
This can be grown up to an elevation of 5,000 or 6,000 feet. On 
account of the altitude the nights are too cold for the successful culti- 
vation of corn and many other of the coarse forage grasses grown in 
the prairie regions to the east. Sorghum and Kafir corn are grown 
to some extent in Colorado for forage. Timothy is grown, especially 
in the mountain region; it is used for both pasture and hay. Red 
clover is raised in Montana and to some extent in the two States to 
