Nitrogen Recalibration for Corn in North Dakota

The nitrogen (N) recommendations for corn in North Dakota (ND) need to be updated using actual field results from ND. Existing recommendations are based on Minnesota data, and older ND field calibration data. There have been many changes in cropping systems especially conservation tillage adoption, weed control, and corn hybrid genetics. Many of the newer hybrids are more resistant to water limiting conditions experienced in parts of ND. The study will consist of N response research experiments at a number (8 to 10) of sites depending on resources and locating suitable field research sites. This study will be conducted for two years to generate data for up to 20 site-years of research results.


22 Feb 2011

2010 Annual Interpretive Summary

This project is intended to be conducted for 3 years, at 15 to 16 sites each year in order to gather sufficient data to allow the development of N recommendations for dryland corn in various corn-growing regions of North Dakota. Each site was carefully selected after being screened for residual N so that soil N levels were low enough to ensure crop response to added N fertilizer. Six N rates (check, 40 lb N, 80 lb N, 120 lb N, 160 lb N, and 200 lb N) were applied to each individual small plot, which were planted to corn by growers. Any row starter of other fertilizer applied to the experimental plots was noted and the N it included was added to the known available N pool for the plots. When the plots were in an annual legume, such as soybean or dry bean, a 40 lb N credit was also added to the known available N pool. When the corn was in the 8 to 12 leaf stage, a Greenseeker® sensor was used over each plot in the 16 most eastern experiments. The ears were collected, dried to about 10% moisture, and then shelled. Grain yield was determined along with its moisture content and test weight. Final statistical analysis will be done after all data from the planned 3 years of research is grouped and analyzed. ND-16