In the agricultural setting, nutrients are the building blocks for plant growth and production. Common nutrients are the elements nitrogen and phosphorus which are available in several forms. NRCS works with Iowa farmers to manage nutrients.
The 590 Standard is the guidance document for the creation of a NMP
Iowa NRCS and Iowa State University has developed an Iowa Phosphorus Index (PI). The Iowa PI is an assessment tool for the purpose of evaluating the potential of off-site phosphorus movement. This Iowa PI is to be used when a NMP is being developed based on the 590 Standard and one of the following conditions exist: 1. When manure is applied. 2. Soil loss is above the tolerable level (T). 3. The planning area is within an identified nutrient impaired watershed. 4. The soil test phosphorus levels are above optimum.
The Iowa Phosphorus Index Calculator (XLS, 4.6 MB) (To save this file, right click on the link, save target as..., name and save file where desired, open the file where saved.)