INCREASING FORAGE YIELDS ON INTERMOUNTAIN WINTER RANGES 13 
erately grazed areas at the Desert Experimental Range, including both 
range allotments and pastures, serve to illustrate how these factors 
are related in determining the importance of various species as forage 
(table 1). 
Only a few of the plants whose herbage is utilized at 45 percent or 
more are relatively abundant and occur widely over the winter range. 
These include winterfat, Indian ricegrass, galleta, and globemallow. 
Other species such as hopsage, black sagebrush, bud sagebrush, four- 
wing saltbush, squirreltail, sacaton, Salina wildrye, and Mormon 
needlegrass, whose herbage is utilized 45 percent or more, generally 
occur in limited subtypes or comprise only moderate or minor amounts 
of vegetation. With the exception of shadscale, species utilized below 
this level occur in only one or two localized plant subtypes or form only 
TaBLE |.—Relative abundance and average utilization of herbage by sheep 
of principal forage plants on moderately grazed pastures and allotments 
at the Desert Experimental Range, 1936-46 
Average 
Species ae , | utilization of 
herbage 
Shrubs: | Percent 
PO PSAGe ep llVe es ee Te Mee en ee 1 | 80 
Sagebrush. blacks. 28320502 8 er Pi ee 2 70 
Wantertat. common 2-128: ise a 60 
Sagebrush. buds iss <2 5 ey eee Ne on 50 
Saltlushs (ourwine- aes oe 1 50 
Savebrushs pingeds22 272i en Ae eee ie ila 40 
SumuImer-cy press evay = sso ee 1 | 35 
Saltbush Gardner. 222 o55 2 ee i 1 | 30 
Saltbush, shadscales<. 2.0 so 2 ie ESE i 25 
Mountain-mahogany, littleleaf__.________________ 1 | 25 
Bphedra, Nevada te 8 ao Ue Oia at ea 2 20 
Snakewecd «broom eae ee a ee 2 15 
Rabbit brushtismalies: a2. sek he ei eee 3 10 
Rabbitbrushe Tu blberes ss Scat S ee he LT 10 
Grasses: | 
Squirreltail, bottlebrush=«=" 202 75 tei. is Sa 75 
Sacatone alkaline et cee oe ee 3 | 75 
Riceerass indian eee a ae 4 | 75 
WWildiviewSalinai ce se we. ae ah 2 | 45 
Galle tas ey ee Se ee Ge 5 45 
Needlegrass,. Wormons se ea eS 1 45 
Wheatgrass, bearded bluebunch__________________ 2 30 
Dropseed=: Sands shy 5 ee Oe te 3] 25 
Dropseed spike’. 272 see ee 1 | 20 
Grama les rs ee ee ea | 20 
Forbs: 
Globemallow,, cooseberryleat. 2 ="= 23. 2 4 80 
REPDERWECU oe er ee Fa hae re Oe aie ZA 25 
Russian-thistle tumbling: <2 282255 3 10 
_’ Based on a scale from 1 to 5: 1, occurring infrequently in minor subtypes; 2, well- 
distributed in minor subtypes or infrequent in major subtypes; 3, present in moderate 
numbers in major subtypes; 4, well-distributed in one or more major subtypes - 
5, dominating one or more major subtypes. 
