No one wants to lose—or can afford to lose—nutrients needed for crop production. Keep It For the Crop and the Illinois Fertilizer and Chemical Association recommend these best management practices to help prevent future regulations.

1. If you fall apply anhydrous ammonia, protect your nitrogen investment and protect the environment: USE A NITRIFICATION INHIBITOR. Used at appropriate rates, inhibitors are proven to reduce nitrification and protect against nitrate leaching losses.

2. To further reduce the potential for nitrogen loss, wait until the daily maximum soil temperature at 4 inches is 50°. Measure the soil temperature in your field. Soil temps by region are also available at The soil temperature, not the calendar, should be your guide.

3. Fall-applied nitrogen should NOT be applied on poorly drained soils, soils with excessive drainage, soils low in organic-matter content, sandy soils or soils that cool down late and warm up early.

4. Use the appropriate rate to get the maximum return on your nitrogen investment. Go to and utilize the nitrogen rate calculator.

5. Manage nitrogen as a system instead of an application—consider split applications. Talk to your certified crop adviser/nutrient management adviser about applying part of your nitrogen closer to when the crop needs it most.

6. Soil test on a regular and consistent basis (at least every 4 years) to assure proper management of P, K and pH. Variable rate applications can also improve nutrient efficiency and economic return under certain conditions.

These guidelines apply state-wide in Illinois. Use the 4R’s: Right Source, Right Rate, Right Time, Right Place. Go to to learn more about the 4R framework and recommendations for nutrient stewardship.

This document references the 24th Edition of the Illinois Agronomy Handbook.