Orange County NC Website
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than slope, for forest land use are identified below. Where no limitations exist, a soil is assigned a rating <br /> of 1.00. Ratings for clayey and wet soils were based on similar ratings used in a county in the Piedmont <br /> section of Virginia. <br /> TABLE 2.2.10 - SOIL LIMITATION RATING <br /> Soil Characteristic Rating <br /> No limitations 1.00 <br /> Clayey 0.40 <br /> Excessive wetness 0.10 <br /> Source: Soil Survey of Orange County, NC, USDA, Soil Conservation Service <br /> Forest Land Relative Value Rating <br /> To develop relative values for Orange County soils, the ratings derived above are first displayed <br /> for each soil (see Table 2.2.11). Next, a composite value is obtained by adding the ratings for each soil <br /> series. As an example, the composite value for Appling(ApB) soil is 3.60, the sum of cob imns 3, 4, 6, and <br /> 8. The composite value for Herndon (HrC) soil is 3.35. <br /> Relative values are obtained by arranging the soils in descending order of composite value,dividing <br /> the composite value of each soils series by the highest composite value obtained, and multiplying the <br /> quotient by 100 to produce a whole number. For example, the relative value of Appling (ApB) soil is 100 <br /> (3.60/3.60 = 1.0 x 100 = 100).The relative value for Herndon(HrC) soil is 3.35/3.60 = 0.93 x 100 = 93). <br /> Forest Land Group Value Rating <br /> Unlike cropland, forest land soils are rated and placed into groups using a different technique. <br /> Group 1 still contains the best soils for forest land use and is assigned a relative value of 100. The relative <br /> value for lower groups, however, is the average of the relative value range. <br /> Based on their relative values, soils are again grouped into approximately 10 groups. Fewer than <br /> 10 groups are permissible, though, depending upon the number of soil types present and their suitability <br /> for forest land use. A range in values for all of the soils in each group is then assigned, with no overlap <br /> occurring in the ranges of adjacent groups.The average of each relative value range is then calculated and <br /> becomes the relative value for that group.As an example, the relative value range for Group 3 is 83 to 88. <br /> The group relative value is the range average or 86. <br /> It is the group relative values that are used to calculate the value of one site relative to another <br /> for forest land use. The assignment of relative value ranges and the calculation of group relative values <br /> is shown in detail on Table 2.2.12. <br /> 2.2.17 <br />