Northwest Missouri growers prefer fall application of ammonia as this spreads out the workload and springs can be wet causing application delays.

There are risks from the ammonium to be converted to nitrate during late winter or very early spring. When conversion takes place, nitrate moves with soil water. As in 2019, some nitrogen was leached deeper into the soil.

Nitrification inhibitors may be part of anhydrous ammonia management. Nitrification inhibitors slow the activity of bacteria, which slows the conversion ammonium to nitrate. During warm spring weather, inhibitors are broken-down quickly and lose effectiveness. Nitrification inhibitors typically work better in cold weather and delay nitrification longer.

Growers typically ask “will nitrification inhibitors pay or not?” We cannot accurately answer this question as we do not know the specific weather events that will happen in the future. However, substantial losses can occur in June as soil temperatures move into 80 degrees F. and soils are water logged.

Always keep those fields which have a high risk of nitrogen losses. Those fields may be better suited to delayed nitrogen applications or change methods of application such as top-dressing corn while growing.

For more information, contact Wayne Flanary, Field Specialist in Agronomy at 816-279-1691, University of Missouri Extension.