Phosphorus in soil is tightly held to soil particles, is immobile, and does not leach. Consequently, contamination of groundwater is rarely a problem. This publication dicusses phosphorus as a surface water quality concern. Many human activities contribute phosphorus to surface waters. Activities associated with modern agriculture often significantly increase soil erosion and water runoff from land and transport sediment into surface waters.
Sediment is a prime carrier of phosphorus.
Numerous BMPs for the control of runoff and soil erosion are available. These practices reduce contaminant transport to surface waters. Practices for runoff and soil erosion control include both management practices and physical structures. Fertilizer recommendations based on research and soil sampling Phosphorus application rates for Idaho crops should be based on scientific information. Reliable fertilizer recommendations are developed by calibrating and correlating laboratory soil test values with results of plot research on crop response to fertilizer application rates.