CONSUMPTIVE USE OF WATER BY CROPS AT SWIFT CURRENT, SASKATCHEWAN

Abstract

Irrigation water was applied by the surface method to nine perennial and five annual crops grown at Swift Current. Soil moisture content was maintained between 50% of available moisture and the field capacity. Soil moisture stresses were measured by tensiometers. The total water use and peak requirements varied depending on the season. The total mean water use for perennial forages varied from 589 to 688 mm, and averaged 526 mm for wheat, 486 mm for barley, 610 mm for sugar beets and 560 mm for potatoes.Consumptive use: evaporation ratios were calculated from the Experimental Farms buried tank, a Class A pan, and black Bellani plate atmometers. The water use to evaporation ratio (U: E) from the Experimental Farms buried tank ranged from 0.81 to 1.14, for the Class A pan it was from 0.53 to 0.75, and for the black Bellani plates from 0.321 to 0.446. In all cases the perennial crops were at the higher end and the annual crops were at the lower end of the range.Three to eight irrigations were applied per season. Seasonal water use by annual crops was slightly higher at Swift Current than the rates reported for Lethbridge and Vauxhall, Alberta.