Submitted to: Better Crops
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/1995
Publication Date: N/A
Interpretive Summary: Studies have shown that regardless of the source (organic or inorganic), runoff losses of N and P from fertilized pasture are relatively small proportions of the amount applied. These losses are also associated primarily with soluble N and P forms, rather than particulate forms, indicating that reducing erosion from pasture fields will have little impact on reducing nutrient losses. Grassed filter strips can be quite effective in reducing nutrient losses. The key to using grassed filter strips to the best advantage is to use the appropriate length and maintaining them properly.
Technical Abstract: Nitrogen and phosphorus runoff from pastures fertilized with either organic or inorganic fertilizers has been shown to be a problem. The objective of this research was to determine if N and P losses from pastures could be reduced using grassed filter strips. The research was conducted on small plots that were 80 ft. long. Animal manure was applied to the upper 10 ft. of the plots, with the remaining area being unfertilized. Rainfall simulators were then used to provide a 5 cm per hour storm, sufficient in time to cause 30 minutes of runoff. Runoff samples were collected and analyzed for N and P. Results indicate that grassed filter strips were very effective in reducing N and P losses by up to 90%.