Instinct® II Nitrogen Stabilizer Reduces Nitrification in US Spring Wheat Fields.

Instinct^® II (nitrapyrin) has been applied with nitrogen fertilizers to effectively reduce nitrification in corn fields throughout the Midwest and Southern US.  However, there has been little use of Instinct II in spring wheat fields, which includes approximately 5 million hectares in the US, despite the widespread application of nitrogen fertilizers in these fields.  Field research conducted from 2012 to 2014 in some of the primary spring wheat producing states (Washington, North Dakota, and Minnesota) with urea and UAN fertilizers demonstrated that the addition of nitrapyrin with these fertilizers increased the amount of soil NH₄⁺ at the 0 – 30 cm and 30 – 60 cm soil depths.  Increased NH₄⁺ generally persisted 4 to 6 weeks after application.  When Instinct^® II was applied with urea and UAN sources, greater yields were observed in a majority of the treatments.  In summary, results from this research demonstrated that the addition of Instinct^® II with urea or UAN fertilizers stabilizes ammoniacal nitrogen in spring wheat fields which can reduce the amount of nitrogen loss due to leaching and denitrification while at the same time optimizing the potential for greater spring wheat yield.