INCREASING FORAGE YIELDS ON INTERMOUNTAIN WINTER RANGES 33 
24, and 40 percent under light, moderate, and heavy grazing. Bud 
sagebrush and other minor species, including all forbs, did not show 
any consistent trend in grazing intensity during the period of study. 
SHADSCALE-INDIAN RICEGRASS SUBTYPE 
A shadsecale-Indian ricegrass subtype was divided by fencing when 
the experimental range was established in 1934. This subtype extended 
from inside the northeast corner of the fenced allotments of the experi- 
mental range into the unfenced range beyond. On both areas the 
vegetation was badly depleted and production was low. Amounts of 
herbage and usable forage were recorded in 1937 after the two areas had 
been subjected to grazing at different levels for 4 years (table 8). 
TaBLE 8.—Production per acre of air-dry herbage and forage within a 
shadscale-Indian ricegrass subtype after 4 years’ grazing at moderate 
and heavy intensities, 19357 
Moderate grazing | Heavy grazing 
Species | 7 Se 
Herbage | Forage Herbage | Forage 
Shrubs: Pounds Pounds Pounds Pounds 
Dm dSealem tee ees 152.5 BO. L 148.4 Bias 
‘Blackesazebrush= =e Sse yo NS 11.5 shal 2.9 es 
Nalin Ge Tpley re ts oe er 30.7 18.4 4.5 26% 
OGhemmisc ete eae 12.8 3.8 | Dili O| 6.5 
All:shrubs:= 2 22 2: 207) 5 | 68.4 | 176.9 | 48.1 
Grasses: | 
Ingiannicesnasss=22 83 Ue aes te 166.7 | 125-0} S14 23.6 
OGiner Besa See es | 14-8 | 4.4 | 1.4 A 
INE OTaSSCs see eens es 13165 WB) ae | 32.8 24.0 
ROD Ses sees oS 8 ie Sh (1) (1) | (2) @) 
Ro tial metas Se S52 389 .0 197.8 | 209.7 72.4 
1 Less than 0.1 pound per acre. 
By 1937, after 4 years of grazing treatment, total herbage production 
on the moderately grazed experimental range area was almost twice as 
great as on the adjacent heavily grazed area. Production of the 
palatable species—winterfat, black sagebrush, and Indian ricegrass— 
was far greater under moderate grazing. Black sagebrush produced 
about five times more herbage and winterfat almost seven times more 
on the moderately grazed range than on the heavily grazed. 
In 1934, a drought year, Indian ricegrass produced about 30 percent 
of the total herbage. By 1937 it produced 167 pounds of herbage per 
acre, more than 40 percent of the total within the moderately grazed 
area, but it produced only 31 pounds per acre or about 15 percent of 
total herbage yield under heavy grazing. The great increase under 
moderate grazing made Indian ricegrass by far the highest producer of 
