An economically optimum nitrogen rate (EONR) is a nitrogen rate that maximizes the returns on investments in nitrogen application. This rate depends on how responsive your soil is, how weather affected the growing season, current costs for various forms and applications of nitrogen and projected revenues from the yield. Calculating a true EONR prospectively is very difficult. However a simpler form of the EONR is often referenced in calculators like the Maximum Return to Nitrogen (MRTN).
Making a recommendation for optimal nitrogen application to maximize profitability involves the following steps:
- Determining if your soil will respond to added nitrogen
- Estimating how much additional yield you could obtain from the soil
- Determining how much nitrogen is required for this additional yield
- Making corrections based on historic data, tillage and other relevant management practices