Without protection, fertilizers are vulnerable to nitrogen loss and UAN is no exception. But your nitrogen investment is worth protecting, so you need to know the value that a stabilizer adds to the equation.
Determine your risk factors
No matter how UAN is applied, it can be at risk of all three forms of loss: volatilization, leaching and denitrification. But when protected with a nitrification or urease inhibitor, growers can ensure their nitrogen is available to the plant when it needs it most.
Knowing what form of loss you’re most vulnerable to is the first step in mitigating your risk factors.
- Ammonia volatilization occurs within days of application as ammonium is converted to ammonia gas on or near the soil surface. During urea hydrolysis, the pH in and around the zone of UAN application increases and causes ammonium to convert to ammonia gas. Surface-applied or shallow-incorporated urea or UAN are most at risk. Other risk factors include warm air temperatures, high residue, elevated soil pH, and high soil moisture. Up to 75 percent of nitrogen in UAN is at risk to ammonia volatilization.
- Nitrate is susceptible to leaching when the soil exceeds its ability to hold moisture and the air spaces between soil particles become filled with water. Gravity then takes nitrate and that water through the profile, eventually making it unavailable to the root zone. An extended time period between nitrogen application and crop uptake can also factor into an increase in leaching. Unprotected, 100 percent of the nitrogen in UAN is at risk to loss by leaching.
- Denitrification occurs when microorganisms in saturated soil get their oxygen from nitrite and nitrate forms of nitrogen. Within weeks of application, nitrous oxide gas is formed and then lost into the atmosphere. UAN applications made early in the season, before the period of significant crop uptake, increase the risk for denitrification losses. Unprotected and in poorly drained soil, 100% of the nitrogen in UAN is at risk to loss by denitrification.
Solutions for nitrogen loss associated with UAN
While environmental factors are out of our control, in-field countermeasures are available to improve the odds. As a global leader in enhanced efficiency fertilizers (EEFs), Koch Agronomic Services (KAS) can help protect UAN investments with both urease and nitrification inhibitors.
These stabilizers can protect nutrients applied both above and below ground to help optimize a crop’s yield potential. Urease inhibitors protect surface-applied fertilizers from volatilization, allowing nitrogen more time to be incorporated into the soil. Nitrification inhibitors protect fertilizer below ground against the denitrification and leaching risk factors to optimize the amount available for plant uptake.
- ANVOL® nitrogen stabilizer delivers the longest-lasting urease inhibitor protection over a wider range of soil environments. With the active ingredient Duromide, ANVOL provides above-ground protection against volatilization. Adding ANVOL to surface applications can boost yield results compared to untreated urea.
- CENTURO® is the next-generation nitrification inhibitor for anhydrous ammonia and UAN and the first to be registered by the EPA in more than 40 years. CENTURO extends your window of protection by slowing the conversion of ammonium to nitrate and can hold the nitrogen in the ammonium form three times longer than without an inhibitor.1 Treating an injected UAN application with CENTURO improves yields by providing below-ground protection against denitrification and leaching.
To determine which nitrogen stabilizer solution your operation needs to optimize yield potential, speak with your KAS sales representative to find your local retailer.
1The underlying data is based on third-party laboratory studies funded by Koch Agronomic Services; results may vary based on a number of factors, including environmental conditions. Improvements in nutrient use efficiency, yield and nitrate leaching may not be observed in all cases. Before use, consult the product packaging and labeling for information regarding the product’s characteristics, uses, safety, efficacy, hazards and health effects. Always read and follow label directions.