Grass provides the cheapest and most effective short-term erosion control. It grows quickly and covers the ground completely. To find the bet seed mixtures and plants for your area, check with your local nursery, the U.S. Department of Agriculture Soil Conservation Service, or the University of California Cooperative Extension.   Then, install erosion control blankets to stabilize the area against storm events that might wash the seed away.

Mulches hold soil moisture and provide ground protection from rain damage. They also provide a favorable environment for starting and growing plants. Easy-to-obtain mulches are grass clippings, leaves, sawdust, bark chips and straw. Straw mulch is nearly 100% effective when held in place by spraying with an organic glue or wood fiber (tackifiers), by punching it into the soil with a shovel or roller, or by tacking a netting over it. Commercial applications of wood fibers combined with various seeds and fertilizers (hydraulic mulching) are effective in stabilizing sloped areas. Hydraulic mulching with a tackifier should be done in two separate applications: the first composed of seed fertilizer and half the hydraulic mulch, the second composed of the remaining mulch and tackifier. Commercial hydraulic mulch applicators - who also provider other erosion control services - are listed under "landscaping" in the phone book.

Mats of excelsior, jute netting and plastic sheets can be effective temporary covers, but they must be in contact with the soil and fastened securely to work effectively.  There are an array of erosion control products that can be specified.... contact a reputable company for guidance in their usages ( i.e. Watersaver Company)