INCREASING FORAGE YIELDS ON INTERMOUNTAIN WINTER RANGES 07 
These capacities were calculated by multiplying the air-dry herbage 
yields obtained on the range areas in different conditions by the average 
percentage utilization recorded on the moderately grazed experimental 
range. The result was divided by 5.5 pounds, which is the approx- 
imate range forage requirement including trampled herbage for a ewe 
per day. 
There is considerable variation in grazing capacity according to the 
composition of a subtype and its condition. Subtypes where winterfat 
and black sagebrush are abundant have the highest capacities and those 
where shadscale is predominant, the lowest. 
Subtypes in poor condition have a thinner cover of plants, usually 
including few of the palatable species and a great many of the less 
palatable. Because such range areas produce much less forage, grazing 
capacity is only one-half to two-thirds that of comparable areas in fair 
to good condition. 
MANAGEMENT PRACTICES 
After a program of moderate grazing has been installed on any winter 
range area, it is of paramount importance to apply the best manage- 
ment practices. The management practices outlined here will greatly 
aid in obtaining uniform distribution of sheep, effective utilization of 
forage, and efficient sheep production. 
SUBDIVISION OF RANGE ALLOTMENTS 
The subdivision of a large range allotment into smaller units that 
are grazed at specified winter periods, as practiced at the Desert Ex- 
perimental Range, has several advantages over random grazing of the 
entire allotment. This is especially true when the periods of grazing 
on units are rotated from year to year. 
A new supply of a mixture of forage is assured when sheep are re- 
moved from one unit and brought to a previously ungrazed one. 
Another advantage is that portions of an allotment can be reserved for 
use during shearing in portable corrals on the winter range. 
General observations at the Desert Experimental Range indicate 
that several forage species made superior gains in volume on units 
grazed during the early and middle winter periods but not in the late 
winter. These species included bud sagebrush, Indian ricegrass, hop- 
sage, and squirreltail. All begin their growth in the early spring, which 
coincides with the late winter grazing period, and grazing them at that 
time reduced their vigor considerably. To permit maximum production 
of these species it may be necessary to eliminate the late winter grazing 
on a portion of the allotments each year. This can be accomplished 
by rotating the use of three or more units so that some of the units are 
not grazed in the late winter period for one or two years in succession. 
HERDING 
The following herding practices are recommended on the basis of 
experience at the experimental range: (1) Allow sheep to spread out and 
graze quietly and keep trailing in groups to a minimum; (2) plan routes 
