ND Nitrogen Calculator

Crop Nitrogen Recommendation Calculator for Use in North Dakota

This application provides four NDSU crop nitrogen recommendation calculators for use in North Dakota sunflower, corn, hard red spring wheat/durum, and 2-row malting barley, respectively.

These calculators are designed only for use by growers and crop consultants working within in North Dakota. The corn calculator might also be useful in northwest Minnesota, the northern tier of counties in South Dakota, and southern Manitoba, since data from these areas were used to build the algorithms embedded within the recommendations; however, consideration of local Province or State recommendations should also be given.

The research N-rate data-base underlying these calculators is from the many-years of field research conducted by Dr. David Franzen, Soil Extension Specialist at North Dakota State University, and others.

Wheat nitrogen recommendation calculations are based on an economic production function that takes into account the yield response of the crop to added N, less the cost of the N. The recommendation is based not only on the yield increase from additional N, but the price of the commodity and the cost of N. More details about this "Maximum Return to Nitrogen" recommendation system can be found here or in the section of "Documents".

The recommendation provided also includes a "plus-minus" value. Although many experiments were used to develop these recommendations, there is no way for us to know the N supplying capability for the soils in each field in North Dakota. Therefore, we leave it to the growers and their consultants to fine tune recommendations with their knowledge of specific field characteristics. This is especially important in wheat, where variety choice influences protein and the need for more or less N. Also, choice of N application method and decision to use effective urease or nitrification inhibitors may modify N rate.