Vegetative filter strips (VFS) for control of sediment generated from bare ground not protected by mulch or plant cover were studied. Plots consisted of a 4.6-meters clean-tilled upslope sediment source area and a 12.2-meters VFS located downslope from the sediment source area. VFS consisted of pure stands of six adapted cool season grasses and two cereal grains. Sediment laden runoff was transported into the upslope edge of each filter strip. Runoff samples were collected from the lower end of each plot and analyzed for nonflow weighted sediment concentration. Rate of advance of water through each VFS was measured. Additional measurements were made to define the plant characteristics of each VFS species. In general, planted VFS resulted in a 68% reduction in concentration of sediment in initial runoff from a 50-year, 24-hour storm event on pre-wetted soil. Crested wheatgrass and smooth bromegrass VFS reduced water flow velocity an average of 217% compared to the clean-tilled control plot. The length of time that water remained in the VFS modestly correlated with average sediment concentration in runoff which was 5.5 g/L and 5.0 g/L, respectively, compared to the control plot which yielded 16.3 g of sediment per liter of runoff. Under dry soil conditions sediment concentration in runoff from bromegrass and crested wheatgrass was reduced by an average of 85% compared to the bare control plot. Length of time for water to advance through the smooth bromegrass and crested wheatgrass VFS increased an average of 325% compared to the length of time to flow through the clean-tilled bare strip.

Fasching, Richard A. and Bauder, James W. Evaluation of agriculture sediment load reductions using vegetative filter strips of cool season grasses.