Polymer Coated Urea in Turfgrass Maintains Vigor and Mitigates Nitrogen's Environmental Impacts

Polymer coated urea (PCU) is a N fertilizer which, when added to moist soil, uses temperature-controlled diffusion to regulate N release in matching plant demand and mitigate environmental losses. Uncoated urea and PCU were compared for their effects on gaseous (N 2 O and NH 3 ) and aqueous (NO 3 - ) N environmental losses in cool season turfgrass over the entire PCU N-release period. Field studies were conducted on established turfgrass sites with mixtures of Kentucky bluegrass ( Poa pratensis L.) and perennial ryegrass ( Lolium perenne L.) in sand and loam soils. Each study compared 0 kg N ha -1 (control) to 200 kg N ha -1 applied as either urea or PCU (Duration 45CR®). Application of urea resulted in 127–476% more evolution of measured N 2 O into the atmosphere, whereas PCU was similar to background emission levels from the control. Compared to urea, PCU reduced NH 3 emissions by 41–49% and N 2 O emissions by 45–73%, while improving growth and verdure compared to the control. Differences in leachate NO 3 - among urea, PCU and control were inconclusive. This improvement in N management to ameliorate atmospheric losses of N using PCU will contribute to conserving natural resources and mitigating environmental impacts of N fertilization in turfgrass.