Effect of Supplemental Water on Barley and Corn Production in a Subhumid Region1

Abstract

AbstractA 3‐year field experiment was conducted on a loam soil in eastern North Dakota to determine the effect of supplemental water, added in various quantities and at different times, on malting barley (Hordeum vulgare, L.) and corn (Zea mays, L.) silage production. Irrigation consisted of (a) none; (b) after previous harvest only (to fill 120‐cm profile); (c) 6 cm applied per irrigation as needed during growing season; (d) after previous harvest plus 6 cm at anthesis; (e) after previous harvest plus 6 cm applied as needed during the growing season; and (f) after previous harvest plus 9 to 12 cm applied as needed during the growing season. Water added after harvest was not reflected in soil water content by seeding time the following spring or in increased crop yields, indicating that fall irrigation was of little value. A linear regression (r = 0.89) existed between total water use and both barley grain and corn silage production, with no distinct differences between the six water treatments evident. These results suggest that stored soil water, growing season precipitation, and added irrigation water are all equally effective in enhancing crop production, and within the range studied, one can be substituted for the other. The results also suggest that such factors as amount of water added per event and frequency or timing of events may be of less importance in subhumid than in more arid climates.