Abating Endosulfan from Runoff Using Vegetative Filter Strips: the Importance of Plant Species and Flow Rates

The effectiveness of tall fescue and switchgrass filter strips in removing dissolved endosulfan from runoff flowing at different rates was studied. No preferential removal of one endosulfan isomer over the other was observed, and total endosulfan removal was in the 98-100% range of that applied for the 2.7 l/min runon application rate, and in the 39-54% range for the 6.0 l/min application rate. All applied runon infiltrated fescue beds at the lower flow rate but only 29% penetrated beds at the faster rate. Endosulfan concentrations were reduced in overland flow by about 60-80% at the 1.7 l/min rate and by 27-39% at the 6.0 l/min rate. Most of the insecticide was removed in the first one-third of the filter strip.