Filter strips lose effectiveness when channelized flows occur. Filter strips are normally vegetated with grasses that are suitable to the site and that will adequately filter runoff. A filter strip may require some earthwork before seeding. Often, however, existing pasture areas with well-established forage can serve as the filter strip. The width, or length of flow, of a filter strip is based primarily on the slope of the land in the strip.
Steeper slopes require wider filter strips.
Filter strips require some management for successful and continued operation. The objective is to maintain a uniform stand of vegetation and have the runoff flow as a uniform sheet of water across the surface. Overgrazing and traffic damage to the vegetation needs to be avoided. Excessive vegetative growth and sediment deposits may also cause channelized flows to occur. Fertilizer requirements for filter strips may also be different from surrounding areas.