lod 
NORTHERN GREAT PLAINS FIELD STATION, 1913-1922 Hal 
In 1917 a 70-acre pasture for deferred and rotation grazing was 
established. It is referred to as the rotation pasture. This is the 
system of grazing that has been developed by the Forest Service of 
the United States Department of Agriculture. Grazing started on 
this rotation pasture in the spring of 1918. 
During 1918 and 1919 the rotation pasture was grazed by the same 
number of cattle as the other pastures. In 1920 the number was 
increased to 15. It carried 17 head in 1921 and 16 head in 1922. 
Nv 
BI ES BE IE 
(7O ACRES) ‘ 
LOO PICKLES 
~ 
SO ACRES, | Q W 
HAY LAND 
Ses ae Se = ee ES 8 EE  __ 2a E _ ) Se E 
Fic. 7.—Field plan of the pastures used in the cooperative grazing experiment at the Northern Great 
Plains Field Station: 7, isolation transect; Q, mapped quadrats; C, corrals and water trough; W, deep 
well; M, mowing experiment 
This is approximately the number it should carry which is at the rate 
of 4.375 acres per head. 
A cultivated pasture of bromegrass has been established, and was 
grazed for the first time in 1923. The pasture designated as the 
‘reserve’ is used to carry the cattle before the experiment opens in 
the spring and after it closes in the fall. It is also used during the 
grazing season to carry extra steers to be used as replacements in case 
of accident to any of those in the experiments. The cattle from the 
small pastures are turned on the reserve when their supply of forage is 
exhausted. 
