Targeting Smart Nitrogen
Written by Jonathan Eisenthal
Smart Nitrogen costs a farmer extra, but so does losing nitrogen to the environment. Kelly Nelson, a professor of plant sciences at University of Missouri’s Greenley Research Center has been working with Smart Nitrogen or ESN since the early 2000s.
ESN is a granule of nitrogen in the form of urea, at a 44 percent analysis, encased in a polyurethane coating. As the granule warms, the coating becomes more porous and allows the nitrogen to diffuse through the membrane. Shielded against the vagaries of winter and early spring weather, ESN releases the plant food at the right time.
That’s the concept. Smart Nitrogen cost can be a problem.
At this year’s Nitrogen: Minnesota’s Grand Challenge and Compelling Opportunity Conference, Nelson explained his new paradigm, Variable Product Agrochemical Applications. In other words, he advocates the targeted use of ESN in poorly drained soils.
In a controlled drainage plot planted to continuous corn from 2010 to 2014, ESN reduced leaching losses by 73 percent compared to uncoated urea. The coated fertilizer also reduced loss to the atmosphere by half.
Nelson’s research also demonstrated that ESN can dramatically increase yield in land that tended to get waterlogged, and this is where it really pays.
Nelson said of one of his slides, “You can see the strips where we placed ESN—areas of high-stress, water-logged soils. We didn’t really see huge yield differences in the summit and side slope parts of the landscape, but in the low-lying areas, there were huge yield increases: urea produced 134 bushels, compared to 147 bushels in with a 50-50 preparation of urea and ESN, and 161 bushels with pure ESN.”
There were 321 participants in the on-line nitrogen conference, who attended the fourteen short talks.
“There was a lot of great interaction with questions,” saidProf.Fabián G. Fernández, Nutrient Management Specialist, University of Minnesota. The university organized the conference, along with Minnesota Agricultural Water Resource Center. Fernández said, “Based on the number of questions, there was a lot of interest in the use of ESN as a nitrogen source. We also saw a lot of interest in developing a system of nitrogen credits and determining the economic optimum nitrogen rate (EONR), given the changing climate. Researcher Jeff Vetsch, Prof. Carl Rosen, and graduate student Gabriel Paiao presented on this topic.” Clearly there is interest in Smart Nitrogen and Smart Nitrogen cost in Minnesota and beyond.
See the recorded presentations and the full agenda of the event at Nitrogen: Minnesota’s Grand Challenge and Compelling Opportunity Conference.
