Effect of Real and Simulated Traffic on Coated Fertilizer Prill Integrity and Nitrogen Release

Abstract

The amount of nitrogen (N) from air and soil is not sufficient to produce high quality turfgrass, and thus N fertilizers are often applied. Urea is the most widely-produced and commonly-traded N fertilizer, containing 46% nitrogen by weight. However, it can lead to environmental issues due to its water solubility. One solution is to use slow-release fertilizers, of which polymer-coated urea (PCU) is an example. A slow-release fertilizer such as PCU meters N out over a long period, with N release rates that may vary from 10 to 30 weeks. In high-traffic areas such as football fields or lacrosse fields, one question is the impact that human traffic may have on the integrity of PCU prills. The objective of this project was to 1) examine N release from coated N fertilizer sources as affected by traffic; and 2) examine N release from fertilizer sources as affected by artificial or real foot traffic. Four studies were included, with two short term experiments (1 week) and two long term experiments (9 weeks), using 6 different types of fertilizers. Traffic included natural and artificial foot traffic, with N release determined. Data showed the use of artificial traffic affected and damaged prill coatings, while damage was not significant with natural foot traffic. N sources with a thicker coating tended to be less affected by traffic.