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obtain a publication entitled "Suspended, Canceled, and Restricted <br />Pesticides " which lists all restricted pesticides and the specific uses that <br />are allowed. <br />Applicable Operational BMPs for Vegetation Management: <br />Use at least an eight -inch "topsoil' layer with at least 8 percent organic <br />matter to provide a sufficient vegetation -growing medium. Amending <br />existing landscapes and turf systems by increasing the percent organic <br />matter and depth of topsoil can substantially improve the permeability <br />of the soil, the disease and drought resistance of the vegetation, and <br />reduce fertilizer demand. This reduces the demand for fertilizers, <br />herbicides, and pesticides. Organic matter is the least water-soluble <br />form of nutrients that can be added to the soil. Composted organic <br />matter generally releases only between 2 and 10 percent of its total <br />nitrogen annually, and this release corresponds closely to the plant <br />growth cycle. Return natural plant debris and mulch to the soil, to <br />continue recycling nutrients indefinitely. <br />Select the appropriate turfgrass mixture for the climate and soil type. <br />Certain tall fescues and rye grasses resist insect attack because the <br />symbiotic endophytic fungi found naturally in their tissues repel or kill <br />common leaf and stem -eating lawn insects. However, they do not, <br />repel root -feeding lawn pests such as Crane Fly larvae, and are toxic to <br />ruminants such as cattle and sheep. The fungus causes no known <br />adverse effects to the host plant or to humans. Endophytic grasses are <br />commercially available; use them in areas such as parks or golf <br />courses where grazing does not occur. Local agricultural or gardening <br />resources such as Washington State University Extension office can <br />offer advice on which types of grass are best suited to the area and soil <br />type. <br />• Use the following seeding and planting BMPs, or equivalent BMPs to <br />obtain information on grass mixtures, temporary and permanent <br />seeding procedures, maintenance of a recently planted area, and <br />fertilizer application rates: Temporary and Permanent Seeding, <br />Mulching, Plastic Covering, and Sodding as described in Volume II. <br />• Adjusting the soil properties of the subject site can assist in selection <br />of desired plant species. For example, design a constructed wetland to <br />resist the invasion of reed canary grass by layering specific strata of <br />organic matters (e.g., composted forest product residuals) and creating <br />a mildly acidic pH and carbon -rich soil medium. Consult a soil <br />restoration specialist for site -specific conditions. <br />• Aerate lawns regularly in areas of heavy use where the soil tends to <br />become compacted. Conduct aeration while the grasses in the lawn are <br />growing most vigorously. Remove layers of thatch greater than 3/4-inch <br />deep. <br />Volume IV - Source Control BMPs — December 2014 <br />2-25 <br />