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TR-61 <br />LS (length and percent slope) factors account for the length and percent slope. These factors are taken from <br />Figure 4. Length of slope begins at the top of the micro watershed. This is usually at the top of a hill, ridge, <br />terrace or diversion. The length of slope is considered to end for a given field at one of the following <br />places: (1) the point where the slope decreases to the extent that deposition occurs, (2) the point where <br />runoff enters a well- defined channel, gully, terrace or diversion , or (3) where water leaves the field. <br />Greasewood Reference Area - LS Factor <br />The Greasewood Reference Area is located west of the Colorado River a little over a mile from the North <br />Decline. The DRMS has approved the use of the Greasewood Reference Area for comparison of the <br />vegetation at the North Decline. Since the North Decline has been restored to approximate original contour, <br />the adjacent area will be assumed to have the same LS factor as the North Decline. The LS factor for the <br />adjacent area is based on an average 7% slope at an average vertical height 38.2 feet based on four sections <br />cut across the reclaimed landscape. <br />Average Length 548.0 Feet <br />Average Slope 7.0% <br />Percent Slope (S) <br />6.0% 7.0% 8.0% <br />500 1.600 1.900 2.200 <br />548.0 "LS" Factor 1.948 <br />600 1.600 2.000 2.400 <br />North Decline - LS Factor <br />The LS factor for the North Decline is based on an average 7% slope at an average vertical height <br />38.2 feet based on four sections cut across the reclaimed landscape. <br />Average Length 548.0 Feet <br />Average Slope 7.0% <br />Percent Slope (S) <br />6.0% 7.0% 8.0% <br />500 1.600 1.900 2.200 <br />548.0 "LS" Factor 1.948 <br />600 1.600 2.000 2.400 <br />C (cropping - management) factors are the ratios of soil losses from lands cropped under specified <br />conditions to the corresponding losses from tilled, continuous fallow. C factors for land uses other than <br />cropland are included on Figures 7,8, and 9. The percent ground cover is the primary item to consider <br />because a slight change in the percent ground cover will result in a significant change in the erosion <br />prediction. <br />Figure 7 - "C' Factors for Permanent Pasture and Rangeland <br />ADJACENT AREA - "C" FACTOR <br />Greasewood Reference Area <br />No appreciable canopy. Canopy is assumed to be the cover contributed by trees and shrubs. Based on the <br />2010 Vegetation Evaluation the combined tree and shrub cover totals 11.25 %. The percent ground cover for <br />the reference area shown above is 50.1 %. Use figure 7 identified above and interpolate to determine the C <br />factor for 50.1 % cover. <br />CANOPY NO APPRECIABLE CANOPY <br />PERCENT GROUND COVER <br />40.0% 50.1% 60.0% <br />No G 0.100 0.071 0.042 <br />appreciable I Adacent "C" Factor 0.071 <br />canopy <br />A14 -12-6 <br />03/11 <br />