Evaluation of Particular Mulches as Plant Growth Media and Erosion Inhibitors

Introduction: Increasing public awareness of the desireability of protecting the environment from soil erosion caused by wind and water has centered attention on large construction projects such as highways and housing subdivisions, as well as on individual building sites and parking lots. If unattended, sediment produced from these areas pollutes surface water, restricts drainage, fills reservoirs, damages adjacent land, and upsets the natual ecology of lakes and streams. The search continues for products and practices that will prevent or lessen the amount of sediment leaving construction sites. Products currently in use include chemical as well as organic materials, and they are applied with varying degrees of success. Many designed to stabilize the unprotected soil for a long enough period of time for vegetation to become established are in wide use and are quite effective (Clyde et al. 1978). Moreover, applying organic material to the soil surface around shallow-rooted crops has been a cultural practice for many years (Russell 1961). Janick (1963) summarized the effects of mulching as conservation of soil moisture, reduction of surface runoff and erosion, reduction of evaporation, and possible control of weeds. Others (Borst and Woodburn 1942; Duley 1939) have indicated the value of mulches in reducing runoff and erosion. Mulching has been reported as superior to other treatments for reducing soil and water losses and stabilizing bare slopes before grass is established (Swanson et al. 1965). Gilbert and Davis (1967) and Blaser (1962), in studies of highway slopes stabilization, found mulches improved seed germination and seedling growth by conserving moisture and protecting highway slopes against erosion. Many materials have been evaluated for use as a mulch, including bark, wood wastes, soybean residues, wheat straw, and seawee (Bollen and Glennie 1961; Kidder at al, 1943; Latimer and Percival 1947). McKee et al. (1964) found wheat straw to be one of the best mulches, particularly when used to aid vegetation establishment on steep cut slopes of highways. Osborne and Gilbert (1978) also demonstrated that shredded hardwood bark mulch provided adequate erosion control on highway slopes. CONWED Corporation produces and markets wood fiber mulches that are intended to foster plant growth and inhibit erosion. The objective of this study was to evaluate, using simulated rainfall and sunlight, the effectiveness of various fiber mulches for controlling erosion to facilitate the establishment and growth of barley on a 2:1 (50 percent) slope