Nitrogen (N) is typically one of the largest corn fertilization expenses. Nitrogen application is critical because it significantly improves corn yield in many crop rotations. When choosing N rates, producers need to carefully consider both achieving most profitable economic return and advancing environmental stewardship. In 2004, university agronomists from the Corn Belt states began discussions regarding N rate use for corn production. The reasons for the discussions centered on apparent differences in methods for determining N rates across states, misperceptions regarding N rate guidelines, and concerns about application rates as corn yields have climbed to historic levels. An outcome of those discussions was an effort with the objectives to:
develop N rate guidelines that could be applicable on a regional basis and identify the most profitable fertilizer N rates for corn production across the Corn Belt .
This led to the creation of the new Economic Based Nitrogen Rate Calculator for Ohio. The new Economic Based Nitrogen Rate Calculator provides the user more flexibility in rate decisions by providing a range of rates. Inputs required in this Calculator are the cost of nitrogen and the price of corn. Although the range in rates provided by the model is economic, agronomic considerations are also provided for each rate. Nitrogen credits for previous crop are considered in the model, so you do not have to deduct the credit. Manure credits do have to be taken, so if you apply manure in your operation make certain to credit the nitrogen supplied by the manure.
The Economic Based Nitrogen Rate Calculator is available as a downloadable Excel Spreadsheet file at:
Economic Nitrogen Recommendation Spreadsheet-2007!
The Users Guide for the Economic Based Nitrogen Rate Calculator is available online at:
http://agcrops.osu.edu/fertility/documents/Users_guide_03_06.pdf
For a complete explanation of the new approach to nitrogen recommendations please access the bulletin “Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn” at: http://www.extension.iastate.edu/Publications/PM2015.pdf
Portions of this article are taken from “Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn”.