Spring nitrogen (N) applications are dependent on favorable weather and being able to get into the field in a timely manner. Fall applications of N can help eliminate many of these issues. With ESN Smart Nitrogen, growers can apply all of their N in the fall and not have to worry about another application in the spring, or they can apply part of their N in the fall and increase the flexibility of the spring application program.
ESN, made by Agrium Wholesale, is a controlled-release fertilizer consisting of a urea granule encapsulated in a polyurethane coating. This allows the N to release from the granule at a rate controlled by soil temperature, providing continuous feeding of N when the plant needs it most. This continuous feeding makes ESN a great option for growers where fall N applications are recommended.
ESN has been shown to be an effective alternative to anhydrous ammonia for fall application. ESN can save horsepower and trips across the field, and performs as well as or better than anhydrous ammonia when applications are appropriate.
“ESN performs well in fall applications for areas where the soil stays frozen during the winter,” says Dr. Alan Blaylock, agronomy manager at Agrium Wholesale. “Fall-applied ESN where soils do not stay frozen would be subject to some slow release, if the soil temperature warms up during the winter.”
Fall-applied ESN should be incorporated or subsurface banded and not left on the soil surface over winter. As with all N sources, spring ESN application is preferred over fall application in areas prone to high spring leaching or denitrification. Fall ESN application timing should follow recommendations foranhydrous ammonia—apply when soil temperatures are below 50 degrees Fahrenheit.
Fall applications of ESN can provide benefits for a number of crops. Growers can have a complete fertilization by blending ESN with phosphorous (P) and potassium (K).
“Applying ESN in the fall can help eliminate spring fertilization and planting delays,” says Blaylock. “ESN is an excellent N choice for fall strip-till applications. In addition, ESN is a complete controlled-release nitrogen and requires no messy additives.”
Being able to apply N in the fall is just one way ESN provides flexibility for growers. Besides fall applications, ESN can be applied in a single pre-plant application or top- or side-dressed, depending on weather, field conditions and limited time, allowing growers to implement their preferred management system. Because ESN protects N from loss, it is easily adaptable to many N management programs and application timings.
“Traditional management practices call for farmers to minimize the amount of time N is sitting in the soil, but when you protect N from loss, it allows for more flexibility of application,” says Blaylock. “ESN is like a small storage facility for the N, protecting it until the appropriate time for the crop to use the N. The technology regulates the release of N at the proper time.”