2 CIRCULAR 925, U. S. DEPARTMENT OF AGRICULTURE 
for winter grazing. These semiarid ranges are well suited for such use 
because the forage is composed of grasses and low shrubs that grow 
during the spring and early summer, then dry and cure on the stem 
before grazing begins. Light snowfalls, usually only 3 to 5 inches deep, 
furnish water where permanent watering places are few and scattered. 
This combination of well-cured herbage and easily available snow for 
water generally provides favorable grazing conditions (fig. 1). 
a i ; " — al 
F—440852 
FiGuRE |.—Sheep grazing winter range in western Utah. The soft snow, 2 to 3 inches 
deep, and well-exposed plants provide ideal conditions for winter grazing. Vegeta- 
tion is primarily winterfat and shadscale, with some bud sagebrush. 
Winter ranges of the Intermountain region are located in eastern and 
western Utah, Nevada, southwestern Wyoming, and southern Idaho 
(fig. 2). Similar ranges extend into adjacent States. These ranges lie 
in great blocks, often several million acres in size and usually at. con- 
siderable distances from spring-fall and summer range lands. 
In October most of the sheep within the region are trailed 50 to 200 
miles from the spring-fall ranges to the winter ranges, returning over 
the same trails in April and May (7).!. They are moved to the higher 
mountains for summer grazing and are brought back to the spring-fall 
ranges at the end of the summer period. 
During the early development of the western livestock industry, 
grazing on the vast areas of winter range was largely a matter of shifting 
animals to new ranges. As those already in use became crowded, sheep 
and cattle were moved into new areas more remote from centers of 
civilization (1). More than 50 years ago, however, almost every part 
of the West suitable for livestock was fully grazed and expansion into 
new territory became impossible. Numbers of animals continued to 
increase even after this and as a result, many winter ranges were seri- 
ously overgrazed. Excessive use of the grazing resources brought about 
reduction of vegetation and loss of soil through increased wind and 
1 Italic numbers in parentheses refer to Literature Cited, p. 61. 
