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3. Defend against erosion A sediment and erosion control plan that conforms to local sedimentation and erosion standards or the best management practices in the EPA's Stormwater Management for Construction Activities (whichever is more stringent) should have the following objectives: a. Prevent loss of soil during construction by Stormwater runoff and/or wind erosion, including protecting topsoil by stockpiling for reuse. b. Also prevent longer term sedimentation of streams, Stormwater drains and/or air pollution with dust and particulate matter. ^ Do not remove valuable trees and shrubs, especially near waterways. Protect them with fencing. ^ Schedule grading for the dry season. ^ Use compost berms, blankets, or socks. The EPA specifes that, depending on the length and height of a particular slope, a I /2-inch to fl- inch layer of mature, screened compost, placed directly on top of the soil, controls erosion by enhancing planted or volunteer vegetation growth. ^ Construct earth dikes or install silt fencing, sediment traps, and sediment basins. ^ Terrace steep slopes. ^ Hydroseed or otherwise plant to reduce bare soil, but do not over- plant for instant color. Annuals and short-lived perennials can be used to fill in areas while larger trees & shrubs become established. Cover crops provide excellent short-term cover that also adds nitrogen and/or organic matter when it is later tilled into the soil. ^ Mulch regularly. ^ Minimize the use of blowers. The likelihood of erosion is lessened, thereby conserving topsoil and protecting aquatic habitat. 4. Amend the soil with compost before planting Compost is thriving with microorganisms one teaspoon can have more than one billion benefcial microbes. Adding good quality compost before planting turf, annuals, perennials, trees and shrubs brings life to the soil and feeds existing soil organisms. Compost is effective in improving problem soils - in particular those that are compacted, heavy clay or sandy, poor in nutrients, or lead contaminated. It is one of the most important practices for a healthy, thriving, Bay Friendly landscape. It is important to first assess the soil for physical and chemical problems. Refer to the section Landscape Locally in these guidelines. ^ If topsoil has been removed and stored during building construction, mix one cubic yard of compost into 3 5 cubic yards of soil before re- spreading. ^ If the topsoil has not been removed then sheet mulching is an efficient means of adding compost & other organic matter while controlling weeds. Refer to the tip on sheet- mulching on page 25 for more information. ^ For turf or groundcover installations: Incorporate I-2 inches (3 I/3 - 6 2/3 cubic yards) of compost into 1000 square feet. Mix it with the top 5-7 inches of soil. ^ For preparing planting beds: Spread 2-4 inches of compost over the surface of the soil and incorporate it into the top 12-24 inches of the planting bed. ^ Mixing compost into the backfll of a planting hole for trees and shrubs may not yield signifcant benefits. Some research indicates that young plants beneft more than mature plants. Some specialists also believe that amending backfll can create such a difference between the soil in the hole and the surrounding soil that the roots don't grow outwards it is as if they are growing in a pot. To prevent this problem, amend the entire bed or create planting holes that are no deeper than the root ball and a minimum of 3 times size of the transplant's root ball. Rough up the sides of the hole. Mix soil from the hole with compost at a rate of I part compost to 3-5 parts soil (by volume) and backfill. Make the hole shallower and create a mound in heavy clay soils. ^ And, consider the conditions under which the plant grows naturally. Some California natives require less fertile soils and compost may not be necessary. ^ Finally, quality compost is important. Use compost made from local green and food waste to maximum feasible. Specify compost from a producer that is enrolled in the US Composting Council's Standard Testing Assurance (STA) program. Benefits Compost fosters a diverse, fertile, and disease suppressive soil. You and your clients may see both long and short- term benefts, including faster plant establishment, decreased fertilizer & pesticide use and lower water usage. ~~ w+, Mulch is placed on miles of freeway hillsides by Caltrans. PHOTO: THE MUNICIPAL WATER DISTRICT OF ORANGE COUNTY, LANDSCAPE MANAGEMENT FOR WATEN SAVINGS BV TOM ASH. 29