Tillage and Irrigation Capacity Effects on Corn Production

Corn production was compared from 2004 to 2006 for three plant populations (62,800, 70,700 or 79,100 plants /acre) under conventional, strip and no tillage systems for irrigation capacities limited to 25 mm every 4, 6 or 8 days. Corn yield increased approximately 12% from the lowest to highest irrigation capacity in these three years of varying precipitation and near normal crop evapotranspiration. Strip tillage and no tillage had 8.8% and 7% higher grain yields than conventional tillage, respectively. Results suggest that strip tillage obtains the residue benefits of no tillage in reducing evaporation losses without the yield penalty sometimes occurring with high residue. The small increases in total seasonal water use (< 20 mm) for strip tillage and no-tillage compared to conventional tillage can probably be explained by the higher grain yields for these tillage systems.