GROWMARK FS reported on May 4 that rising soil temperatures and wet spring weather can increase the risk of nitrogen loss for growers. The company detailed three main pathways for nitrogen loss: surface runoff, nitrate leaching, and denitrification.
The issue is important because proper management of nitrogen helps maximize crop yields and supports agricultural sustainability. Surface runoff occurs when rainfall happens soon after UAN (urea ammonium nitrate) applications, especially in rolling fields, causing up to 25% of the applied nitrate form to wash away if not absorbed quickly. Heavy rain on sandy or tile-drained soils increases the risk of nitrate leaching below the root zone, making it unavailable to crops. Denitrification becomes a concern when warm temperatures combine with several days of saturated soil; under these conditions, bacteria convert nitrate into gas, leading to further losses.
According to GROWMARK FS, “When rainfall occurs after application of UAN, the 25% that is in the nitrate form can be washed down slope if it wasn’t absorbed into the soil before the rain. If the nitrate portion was absorbed into the soil, it could then be pushed lower into the soil profile through leaching.” The company also explained that “all forms of applied nitrogen eventually convert to nitrate through the nitrification process…and at that point can be leached.” In cases where soils remain saturated for extended periods and temperatures are above 50 degrees Fahrenheit, supplemental nitrogen applications may be necessary.
A Late Spring Soil Nitrate Test (LSNT) is recommended if there is uncertainty about remaining available nitrogen. A test result below 25 parts per million suggests significant loss has occurred and additional application may be needed.
GROWMARK FS enhances community well-being by assisting growers in maximizing yields and providing reliable services according to its official website. The organization consists of locally owned cooperative retailers united under GROWMARK according to its official website. It operates through more than 38 local cooperative retailers and offers over 1,000 agronomy and energy products according to its official website.
The company aims to deliver comprehensive solutions across agriculture, energy, and turf management sectors using expert knowledge and a dependable supply chain according to its official website. Its services extend throughout regions including the Midwest, Northeast and Mid-Atlantic United States as well as Ontario in Canada according to its official website. GROWMARK FS provides high-yield seed options along with crop performance products such as grain marketing services; propane; quality fuels; premium lubricants; and professional turf care items according to its official website.
