EROSION CONTROL AND ENGINEERING PROPERTIES OF NATIVE VEGETATION COMPARED TO BERMUDAGRASS

Roadside slope failure, as well as drainage channel and structure siltation, is related to the health and character of the roadside vegetative community. Native grasses and prairie plant associations are well adapted to the harsh open environments of open prairies and plains, a characteristic shared by many highway roadsides. This study hypothesized that the growth habit of native plants, which includes a tough, deep, fibrous root system, and a dense surface protecting cover, may make them better suited for slope protection and erosion control than most introduced grass species commonly used on the roadside. Furthermore, researchers hypothesized that these native vegetation associations would require less cultural maintenance than the introduced grasses and would be less subject to invasion of noxious weeds. The researchers compared the erosion control and surface soil-reinforcing properties of four native grass, wildflower, and forb mixes to common Bermudagrass. The performance testing procedures were in accordance with the test procedures developed by the Texas Department of Transportation and the Texas Transportation Institute (TTI) for the evaluation of rolled erosion control products. Tests were performed at the TTI's Hydraulics and Erosion Control Field Laboratory, College Station, Texas.