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Vegetative filter strips (VFS) are commonly used BMP's to control agricultural pollutants such as phosphorus (P) from milkhouse wastewater. However, the information about P sorption and removal within VFS is limited. This study assessed changes in soluble reactive P (SRP) in the VFS over a period of 11 days after the milkhouse waste application was stopped. Previous research found that wastewater flowed preferentially within the VFS on locations where the soil became saturated. In this study, we show that soils in the saturated area had low Morgan soil test P levels compared to the soils in the relatively drier area. High SRP concentrations of 4.8-9.4mg/l were observed at two locations in monitoring wells immediately after the milkhouse wastewater discharge. It was hypothesized that the high SRP concentration of 9.4 mg/l near the discharge point was due to the highly reduced conditions of soils in the saturated area. The SRP concentration of 4.8mg/l in the downslope area was likely caused by topographic convergence and resulting P transport to this area. The SRP concentrations for the wells in the VFS, including two high SRP locations, decreased to less than 10% of the influent milkhouse waste concentration after diverting the milkhouse wastewater, and once the soil was allowed to dry. These results were in agreement with previous laboratory tests, showing that by drying the saturated soil, the available soil test P values decreased as much as 6 fold. The P may be less readily available when dried soil was used, compared to the standard Morgan test procedure when wet soil was analyzed. Therefore, it was concluded that as long as the soil stays aerobic, the VFS plays a significant role to sorb P from wastewater.