Phosphorus has long been considered a pollutant of streams. The phosphorus in streambanks has not been accounted for and may be significant. We hope to address this issue with a study conducted at the Iowa State Rhodes Research Farm. The purpose of this study is to better understand the relationship between cattle grazing management and the release of phosphorus into our waterways through erosion. Three grazing treatments were spread across six pastures with a common stream running through them. Erosion pins were used to calculate the amount of soil lost into the stream. Deep cores soil samples were taken on the floodplain. Through this, we can evaluate the grazing systems effect on phosphorus loss. Results will be discussed.