Fertilizer Management for Short-season Corn Grown in Reduced, Strip-till, and No-till Systems on Claypan Soil

Abstract

Strip-till is an alternative conservation tillage system that may overcome the yield depression often seen with corn (Zea mays L.) grown with no-till on the claypan soils of the eastern Great Plains. The objective of this research was to determine the effect of conservation tillage systems and fertilizer N-P management on short-season corn. Continuous corn yields with no-till, strip-till in the fall, or strip-till in the spring declined with year compared with corn grown with reduced tillage. By the third year, corn yields with reduced tillage exceeded 45 bu/acre more than with the other tillage systems. In part, this can be attributed to a reduced plant stand in no-till and strip-till systems. Average corn yield was about 10% greater when N-P applications were made in the spring than in the fall. Similarly, knife (subsurface band) applications of N-P resulted in about 12% greater yield than dribble (surface band). Yield differences due to fertilizer timing or placement were related to similar increases in the number of kernels per ear. Strip-till done either in the fall or spring for corn grown in claypan soil did not improve yield compared with no-till and may be less than yields with reduced tillage. Knife applications of N-P fertilizer done in the spring may help mitigate this deficit if the producer prefers the conservation aspects of strip- or no-till systems.