The Economic and Environmental Outcomes of Applying Polymer-Coated Nitrogen to Cool-Season Perennial Pastures in Southern Ontario

Perennial cool-season pasture plays a crucial role in the economic viability of beef production in rural Ontario, particularly for farms with extensive grazing systems. Enhancing pasture yield can extend the grazing season and reduce reliance on supplemental feed, minimizing production expenses. Applying nitrogen (N) fertilizer to perennial pasture has the potential to increase forage yield and optimize land use, by allowing for increased stocking rates. However, concerns remain about the potential environmental impacts, which are essential for reducing long-term input costs. Currently, N fertilizer recommendations for pastures in Ontario are grouped with hay, creating uncertainty for producers about optimal application rates. In a study on a 64-acre pasture in Elora, Ontario, four N application rates of polymer-coated urea applied in spring were evaluated (0, 30, 60, and 90 kg/ha). A total of eight fields were rotationally grazed by cow/calf pairs with stocking rates adjusted to match forage biomass. Results indicated that in each of the two study years, increasing N allowed for increased stocking rates and therefore increased calf production. Crude protein levels also increased with increasing N rates in the first grazing cycle, though this quality boost was temporary. By incorporating N fertilizer into pasture management strategies, rural producers could increase productivity per acre, enabling them to produce more beef with less land, provided that the environmental impacts can remain minimal. This approach could enhance economic returns and support rural communities, making it a valuable tool for addressing rising input costs and land-use pressures in Ontario's agricultural sector.