A study by Dr. Rick Engel from Montana State University proved that surface-applied urea still loses a significant amount of nitrogen due to ammonia volatilization in cold weather, even under freezing conditions. High ammonia volatilization loss under cold conditions was mainly related to high soil moisture and soil pH.
Fortunately, that same study also showed AGROTAIN® nitrogen stabilizer protects against this cold weather loss. At one location, untreated urea lost about 44% of its nitrogen through ammonia volatilization after nine weeks (63 days) while urea treated with AGROTAIN stabilizer only lost about 12%.
Weekly NH3 Volatilization Graph
Cumulative NH3 Volatilization Graph
Silt loam soil (pH 8.3)
Precipitation of 0.8 in between 0–9 weeks
Nitrogen rate of 99.7 kg N/ha
Fertilizer applied on February 26
AGROTAIN stabilizer applied at label rate
Soil temperature was about 0° C at the day of application
Source: Engel et al., 2011. Montana State University.
*The underlying data was provided by Montana State University under a Research Trial Financial Support Agreement with Koch Agronomic Services, LLC and neither Montana State University, nor the individual researchers referenced, endorse or recommend any product or service.