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DocuSign Envelope ID:AEB4824B-973E-408D-9C1C-5EDDD8B50786 <br /> It is imperative that disturbed soils be totally protected from erosion and sediment <br /> loss during construction and before a project is considered complete and <br /> acceptable.Installing appropriate vegetation in an immediate andtimely fashion <br /> is the optimal means of achieving this stabilization. Vegetative specifications <br /> for most exposed soil conditions across North Carolina are provided in this <br /> section of the manual.It should be noted however,that no two sites in the State <br /> are exactly alike;therefore the protective vegetative cover for individual sites <br /> should be carefully selected. Each requires its own investigation, analysis, <br /> design and vegetative prescription as set forth in this section of the manual. <br /> This practice standard describes three stages of vegetative cover; immediate, <br /> primary and long term. Effective and acceptable stabilization can be provided <br /> only when the optimum combination of immediate, primary, and long term <br /> vegetative practices are applied. <br /> The vegetative measures presented in this chapter include application of seed, <br /> sod and sprigs. Use of field and container grown plants are not addressed <br /> in this manual. Planting of these types of vegetation is typically at spacing <br /> and intervals that will not provide the required protective cover. However, <br /> the design professional is encouraged to utilize these larger plants to <br /> compliment the required protective cover, particularly where these types of <br /> plants will provide seed for continued long term cover and wildlife habitat. <br /> PLANNING CONSIDERATIONS <br /> SOILS <br /> Test and analyze the type(s)and quality of the existing soils on a site,their pH <br /> ranges,and their nutrient levels. Taking soil samples from the different areas <br /> of the project site and having them tested at a state or independent lab will <br /> provide a baseline for determining the pH modifiers and additional nutrients <br /> required for the selected plant varieties. <br /> Disturbed conditions on a site may produce a variety of soil communities. <br /> Nutrient and pH levels in deeply cut soils will be quite different from those <br /> soils found on the original surface. When sites are highly disturbed through <br /> mechanical means such as grading,the soils become mixed together in many <br /> different ratios. These areas should be identified and tested. <br /> Results from soil tests will usually include recommended application rates of <br /> soil modifiers such as lime and fertilizer for the selected plant species in the <br /> particular soils. Application rates will be itemized in the report. <br /> The texture of the soil on a site,which is the proportion of sand,silt,and clay <br /> in the soil, is an important physical indicator of the site's ability to support <br /> vegetation. In heavy clay soils amendments may be necessary to provide an <br /> adequately drained planting medium. Conversely, in extremely sandy soils, <br /> amendments may be required to provide for moisture and nutrient retention. <br /> 6.11.2 Rev.5/08 <br />