Yield and Nitrogen Content of Corn under Different Tillage Practices

The objective of the study was to determine whether tillage and residue practices have a significant effect on the yield and N content of corn ( Zea mays L.) under nonlimiting soil N conditions. Nitrate leaching has been identified as a source of non‐point‐source pollution. By identifying tillage practices which maximize corn N uptake, recommendations can be based on how to minimize N loss. A 2‐year field study was conducted in southwestern Quebec on a 2.4‐ha site of a Typic Endoaquent (Humic Gleysol) cropped to corn. Three types of tillage practice (conventional tillage, reduced tillage, and no‐till) were combined with two residue levels (with and without) in a randomized complete block design. The effect of these practices on corn yield and corn N were studied. Seedling emergence rates in spring, and corn moisture content at harvest, were also monitored. Residues hindered initial plant emergence in the no‐till plots. Corn N and moisture contents in 1996 and 1997 indicated that no‐till with residue had a delayed maturity relative to the other treatments. However, total corn biomass and grain yields were not affected by tillage or residue treatments. No correlation between corn yield and corn N content was found.