Northwest and Allee Research and Demonstration Farm
Nitrogen (N) fertilizer management for corn production continues to be a very important issue in Iowa. The goal of N management is to apply enough fertilizer to maximize profits for the crop producer and to limit the potential for environmental contamination from unused fertilizer. The ammonium (NH4) form of N fertilizer doesn’t leach or denitrify in soils. Eventually NH4 is converted to nitrate (NO3) in soils, and once this occurs the potential for N loss increases. Nitrification inhibitors (NI) maintain, for a time, ammonium (NH4) in soils thus reducing the risk of N loss. Research on NIs in Iowa has not shown predictable corn yield increases due to their use, especially when applied in the spring in liquid N fertilizers. This may be because NIs are volatile and may be lost from the soil during application. The purpose of this study was to evaluate a reformulation of the NI nitrapyrin. This product is currently being sold as Stay N. The reformulated product is less volatile than the old material.
Iowa State University
Killorn, Randy and Jensen, Kyle, "Effect of Spring Application of N Fertilizer and a Nitrification Inhibitor on Corn Grain Yields" (2003). Iowa State Research Farm Progress Reports. 1481.