1. Influence of Soil Test Phosphorus on Phosphorus Runoff Losses from South Dakota Soils

Applications of manure and fertilizer phosphorus (P) to soil in excess of optimal crop requirements leads to a buildup of soil test phosphorus (STP) and increases the risk of offsite transfer of P during heavy precipitation events. The first step to developing effective manure and fertilizer P application strategies for South Dakota is to evaluate the relationship that exists between soil and runoff P. The objectives of this study were to: 1) determine the relationship between STP and runoff P concentrations...