Table 9. Per acre production of crude protein from crested wheatgrass plots fertilized annually with ammonium nitrate (33-0-0).
Treatment Crude protein - lbs. per acre 4-year average
1955 1956 1957 1958
Check (No N) 98 64 123 114 100
Very light (25# N) 174 116 265 181 184
Light (50# N) 176 131 293 210 203
Medium (100# N) 244 119 315 261 235