PURPOSES OF COVER CROPS
Cover crops can help reduce soil erosion by protecting it from intensive rainstorms as well as providing a physical barrier to runoff. Cover crops may even help to build new topsoil by adding organic matter to the soil. A cover crop chosen for erosion control provides a quick and dense cover at the desired time of the year. During this time of the year, the otherwise bare soil is protected from erosion. After the cover crop is killed, surface residue mulch created by the dead cover crop provides protection against erosion. Erosion reduction after a cover crop is plowed under is small, although soil structure and infiltration rates are likely to be improved if a cover crop with a fine, extensive root system is used.