Phosphorus Fertilizer and Grazing Management Effects on Phosphorus in Run0ff from Dairy Pastures.

This article discusses the rates of phosphorus runoff related to fertilizer application on grazed dairy pasture plots at Camden, New South Wales in southeast Australia. According to the authors, they found that phosphorus fertilizer applied at four different rates increased phosphorus runoff concentrations significantly. Between runoff events, the magnitude of the effect of phosphorus fertilizer varied. They developed a conceptual model of the sources of phosphorus in runoff. They concluded that the best strategy to minimize phosphorus runoff concentrations in grazed dairy pastures is apply phosphorus fertilizer at or near the agronomic optimum rates.