Fall Ammonia Season
2. Do not apply the full nitrogen rate in the fall. Our industry has done a great job of applying the N rates outlined in the Nitrogen Rate Calculator, but the full rate should not be applied in the fall--save a good part of the rate for spring application, either pre-plant or side-dress. That way you can minimize environmental risk for your customers and give them the flexibility to adjust and apply the rest of the rate in the spring, based on what the weather conditions are.
3. Use a labeled nitrification inhibitor with all fall applied ammonia. This means N-Serve or Centuro; they are labeled by USEPA with active ingredients that at the prescribed rates on the label, are proven to inhibit bacterial activity that converts ammonium to nitrate.
IFCA will start posting the daily soil temperatures on our website next week. We are working with the University of Illinois to outline the timeframe when conditions become appropriate for application, so watch for a Bulletin. It is not an exact science but we have to continue to be cognizant that research shows that nitrogen applied in the fall can lose nitrate to field tiles, and so this risk must be mitigated by following the best management practices.