Study: ESN Protects N, Feeds Crops In Wet Or Dry Weather
Weather may be the biggest variable for a corn crop, but with ESN SMART NITROGEN, farmers can count on consistent yields in wet or dry years.
ESN, made by Agrium Advanced Technologies (AAT) is a controlled-release fertilizer, consisting of a ureagranule encapsulated in a polyurethane coating. This allows the N to release from the granule into the soil, driven by temperature and moisture. The higher the soil temperature, the greater the release of N, so release occurs during the growing season, when the plant needs it most.
“One of the biggest challenges farmers face with their N management programs is the unpredictable nature of weather that can lead to N loss,” says Dr. Alan Blaylock, AAT Agronomy Manager. “ESN provides a more reliable yield response because it reduces the yield loss associated with N loss.”
Research Shows Consistent Yield In Diverse Conditions
Research has shown ESN produces a consistent yield response in a variety of years with very different rainfall conditions, while performance of conventional N sources varies widely from year to year. ESN has shown the yield consistency in a variety of geographies and on a number of different soil types that can present different N management challenges.
Dr. Kelly Nelson, research associate professor at the University of Missouri, has worked with ESN on the claypan soils of Northeast Missouri since 2004. This research has shown gaseous N loss through denitrification loss as the major challenge with urea applications to poorly drained claypan soils.
“ESN can help combat this, because the slow-release properties mimic a side-dress application of N andprovide a steady supply of N throughout the growing season,” says Nelson. “The physical coating protects the urea prill during weather conditions that are favorable for denitrification loss.”
Nelson says that ESN has shown consistent yields in a variety of weather conditions over the years. He adds that ESN also performs consistently well in high-risk areas of the field.
Going from claypan soils to the sandy soils of Nebraska, Dr. Richard Ferguson, soil fertility specialist at the University of Nebraska, has worked with ESN under a variety of conditions.
In three successive years, Ferguson conducted field studies with extreme weather conditions conducive to N loss. In those years, ESN proved to be significantly better than other sources of N, showing as much as 60-80 bu/acre yield increases over UAN solutions with no inhibitors used.
“ESN has protected N from multiple loss conditions, like leaching and volatilization, while many other methods protect against only one form of loss,” says Ferguson. “By keeping N out of the nitrate form in significant quantities, ESN’s gradual release allows more of the N to be available to the crop.”
Ferguson has also conducted lab incubation studies comparing ESN to other fertilizer applications and replicating challenging weather and soil conditions. In both the field studies and the incubation studies, ESN has shown a very predictable response across varying moisture conditions, says Ferguson.
AAT research confirms the assertion that ESN shows consistent corn yields over time.
“We have hundreds of crop-years of data on ESN, showing better uniformity of yield over time, regardless of weather and soil type,” says Blaylock.
ESN’s Continuous Feeding Helps Crops Endure Dry Weather
Nitrogen loss is less of a concern in dry weather, but that doesn’t mean farmers won’t see value from using ESN, even in dry years.
Controlling the rate of N supply helps prevent “luxury growth” of leaf area, says Blaylock. When corn plants grow more leaf area, the plant consumes more of the soil moisture. This can be a concern in dry years, because that soil moisture may be depleted prior to the reproductive stage, when it will be needed for grain fill.
“ESN provides continuous feeding of N that allows the plant to conserve more moisture for grain fill,” says Blaylock.
ESN Prevents N Loss In Wet Weather
Wet seasons threaten N through two major loss mechanisms: leaching and denitrification. In porous soils, watermoves N past the root zone where it can’t feed the corn plant, and potentially into ground and surface water.
Excessively wet soils with less permeability may be prone to denitrification, by which bacteria convert nitrate-nitrogen into gases that can escape into the atmosphere.
“Farmers see the greatest benefits from using ESN when N loss is significant,” says Blaylock. “In some cropping systems, where soils are prone to N loss, farmers may be over-applying N to compensate for the losses. By using ESN, farmers can protect more N from loss, and potentially save money on the front-end, by improving their nitrogen management.”
Protecting Farmers N Investment
AAT believes in the 4Rs of Nutrient Stewardship. The concept of applying the right nutrient source at the right rate, at the right time, and in the right place has been related to agricultural sustainability.
“Managing N takes a lot of guesswork for a farmer — knowing how much to apply and when— and there is always a risk that environmental conditions could negatively impact crop performance,” says Blaylock. “ESN reduces that risk and removes variability, which could allow farmers to do a better job of managing their N budgets.”
Ultimately, the consistency of yields means more economic gains for farmers.
“Yield consistency really means farmers are eliminating the years of down yields by eliminating variations in N,” says Blaylock. “Using ESN to get more consistent yields puts more money in farmers’ pockets.”