What is a phosphorus-based nutrient management plan?
The Act specifies that nutrient management plans consider both nitrogen and phosphorus application rates. Recommendations have always been made for both nitrogen and phosphorus application based on soil and crop information. However, when animal manures or sludge were applied, the amount of recommended materials was based on crop nitrogen needs. This practice resulted in substantial overapplication of phosphorus. Previously, it was thought that if you controlled erosion, you controlled phosphorus loss, so there was little concern about phosphorus loss if good conservation practices were followed. Recent research has shown that dissolved phosphorus in runoff can be high, even without erosion, on soils with excessive soil test phosphorus levels. This finding is the reason the Act requires that nutrient management plans be balanced for both nitrogen and phosphorus. The Act identifies what must be considered in a plan, but does not specify what constitutes a phosphorus-based plan. This pro
