SasaZt. --Three tables (1, 5, and 6) are required to calculate estimated erosion on 

 the Basalt study area. Table 5 lists erosion as a function of plant, litter, and stone 

 cover percent. Table 6 contains correction factors for sand and organic matter content 

 of the surface inch of soil. For example, a site has 80 percent cover, 40 percent sand, 

 10 percent organic matter, and a 30 percent slope. Table 5 indicates sheet erosion to 

 be 0.15 pound per milacre, uncorrected for slope or soil. Table 1 indicates a slope 

 correction of 1.69. Table 6 indicates a soil correction of 0.92. Therefore, estimated 

 sheet erosion is: 0.92 X 1.69 X 0.15 = 0.23 pound per milacre. 



Trinity Mountains .- -The nomogram (fig. 18) for this study area is used as follows: 



1. Draw a line from the plant' and litter cover percentage on line A to the organ- 

 ic matter content of the surface 1 inch of soil on line B. 



2. Draw a line from the intercept on line C to the slope gradient on line D. 



3. The intersection on line E is estimated sheet erosion. 



Table S . --Estimated sheet erosion on the Basalt study area 

 as related to protective cover provided by plants, 

 litter, and stone 



Cover 



: Erosion 



Cover : 



Erosion 



(%) 



: (lbs . /milacre) 



(%) : 



(lbs ./milacre) 



50 



1.36 



70 



.20 



55 



1.15 



75 



.17 



40 



. 76 



80 



. 15 



45 



.58 



85 



.13 



50 



.45 



90 



. 12 



55 



.36 



95 



.11 



60 



.29 



100 



. 10 



65 



.24 







Table (:i . --Correction factors for sand and organic matter content 

 in the surface inch of soil on the Basalt study area 



Organic matter content {% by weight) 



2 \ 4 ; 6 \ 8 I 10 12 :' 14 ; 16 



30 











3 



17 



1 



69 







.91 



0.49 







.26 







.14 



32 







4 



34 



2 



53 



1 



.48 





86 



.50 





29 





17 



34 



5 



15 



3 



27 



2 



08 



1 



.32 





84 



.53 





34 





22 



36 



3 



67 



2 



54 



1 



76 



1 



22 





84 



.58 





40 





28 



38 



2 



68 



2 



02 



1 



53 



1 



15 





87 



.65 





49 





37 



40 



2 



02 



1 



66 



1 



36 



1 



12 





92 



.75 





62 





51 



42 



1 



56 



1 



40 



1 



25 



1 



12 



1 



00 



.89 





80 





71 



44 



1 



24 



1 



21 



1 



18 



1 



15 



1 



12 



1 .09 



1 



06 



1 



03 



46 



1 



02 



1 



08 



1 



14 



1 



21 



1 



28 



1.56 



1 



45 



1 



54 



48 





85 





.99 



1 



14 



1 



32 



1 



52 



1 .76 





03 







50 





74 





93 



1 



17 



1 



47 



1 



85 



2.35 











24 



