From pre-plant to fall and over-winter applications, we’re busting seasonal ESN myths. Soil temperature, heavy rain, fall applications and freezing all top the list in this edition of busting the myths around ESN. Read on to learn the facts about these common misconceptions.
The following is not intended to be complete or detailed use recommendations for all geographies, crops, or applications. User assumes all responsibility for proper use and handling for specific geographies, crops, and applications. Please consult ESN recommendations and/or your Nutrien ESN representative for complete recommendations for use.
Myth #1: ESN release is not sensitive to soil temperature
The release of nitrogen from ESN is soil temperature dependent, but there is not a specific “on-off” temperature. Practically, ESN can start releasing N at temperatures above the freezing temperature of water, since liquid water is necessary for the diffusion process, but ESN releases very slowly at cold temperatures to protect the N when crops are growing slowly. ESN release is very slow at lower temperatures and increases gradually as temperature increases to better match crop N demand.
See the figure below illustrating ESN release at different temperatures.
N supply synchronized with crop demand*
*1. This is a predicted release based on typical release data reported for the product and is not specific to any particular batch or lot. Nutrien does not represent or warrant the accuracy of this data for any particular batch or lot.
2. Predicted release shown is based on product as it leaves the plant and does not represent product that has been blended and transferred as it is applied to the soil.
3. Release in water can be significantly different from release in soil medium.
4. This data is for informational purpose only and should not be interpreted as a recommendation. Weather patterns and soil conditions vary from location to location, and these variations will affect the performance of the product.
Myth #2: ESN will float and wash away in heavy rain
With heavy rains across much of the U.S. this year, nitrogen availability for crops is top of mind. A small percentage of ESN granules are buoyant and may float in water. Some surface movement is possible if surface water flow is strong enough to erode soil in conventional-till or erode residue in no-till. Significant movement of ESN offsite is rare and results from the combination of recently applied ESN, sloping topography, bare soil and sufficient rainfall for erosion – a combination that should be avoided. Light incorporation is preferred where possible to prevent the possibility of granule movement.
Myth #3: ESN shouldn’t be applied in the fall
Where fall N application is an acceptable practice according to soil types, environmental conditions and cropping systems, ESN is a great alternative to other N sources. Spring N application is a preferred practice in many regions. In dryland cropping systems in arid and semi-arid areas, such as Western Canada and the Great Plains, fall may be the preferred application time for ESN. Because the N in ESN remains protected through cold winter periods, it reduces the risk of N loss and can improve N-use efficiency over conventional N sources that pose greater risk. Areas that remain warm and wet through winter and early spring may have increased risk of N loss, so fall ESN application may not be recommended in such areas. In these areas, ESN or ESN blends may be appropriate for some fall-seeded or winter crops.
Consult your ESN dealer or Nutrien representative to discuss fall ESN applications.
Myth #4: ESN granules will break if frozen
Freezing temperatures virtually stop release from ESN. Diffusion of water into the ESN granule is stopped and, if some urea has already begun to dissolve, the release of urea solution through the coating also ceases. ESN granules do not rupture, burst, or disintegrate upon freezing and will persist for long periods intact in frozen conditions. See Use Recommendations for more information.
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