*Rate for split UAN was determined from UNL nitrogen recommendations for corn. “After planting” treatments applied all the N in one broadcast application without incorporation approximately at corn emergence (within two to three weeks after planting). Split UAN was comprised of 30% of total N at corn emergence and 70% of total N at V6 growth stage. Split UAN was applied at 175 lbs N/ac in 2009 and 2010 and 180 lbs N/ac in 2011. Source: Dr. R. Ferguson, University of Nebraska-Lincoln. Reference: Maharjan, et al. 2016, Agronomy Journal 108:509-518.
The percentage of rain occurring in large events has increased. It’s reported that 37% of the total rainfall comes from severe weather events in the Corn Belt. And climatologists are forecasting increasing weather volatility in the future. Unpredictable, severe rainfall events create greater chance for N-loss conditions and special N-management challenges.
ESN Smart Nitrogen performs more consistently in variable weather than other nitrogen (N) products. ESN’s controlled release reduces N loss from large rainfall events. A three-year study by University of Nebraska demonstrates ESN’s consistent performance and yield stability in varying weather conditions.
- Growing-season rainfall during the study was 43% below normal in 2009; 9% above normal in 2010 but much above normal early in the season; and 39% above normal in 2011 with several large rainfall/N-loss events.
- ESN produced similar yield response in all three years of different rainfall patterns.
- Conventional N sources, even recommended split application, failed to provide the same consistency under variable conditions of N loss.
- Nitrogen loss in 2009 was primarily as volatilization since rainfall following N application in 2009 was minimal. Nitrogen losses in 2010 and 2011 occurred in large leaching events.
- Pre-plant ESN at 150 lbs N/acre averaged 197 bu/acre over the three years; split-applied UAN at 175 lbs N/acre averaged 180 bu/acre; pre-plant UAN at 150 lbs N/acre averaged 125 bu/acre.