Table 1 .- -Correction factors for slope gradient 



Study area; — Slope gradient [%) 



^0 •• 15 : 20 : 25 \ 30 35" 



40 



GBEA 0.52 0.66 0.86 1.11 1.43 1.84 2.37 3.06 



^^^^^ -64 .80 1.00 1.25 1.56 1.95 2 44 



Montana .69 .81 .94 1.10 1.28 1.49 1 73 7 



Diamond .64 1.00 1.55 2.41 3.75 -- _ "*_'" 



^^^^^^ -70 .88 1.'09 l!35 1.69 2'l0 2'61 



JllJim -38 .49 .65 .86 1.11 1.46 1.91 2!51 



Daws County Experrmental Watershed. -Protective cover provided by plants and 

 litter explains 76 percent of the variance in the log of soil eroded f^om s^udy p^ots 

 on this area. Three other site factors about equal in secondary importance are- loL 

 gradient; Utter weight; and soil organic matter. These, in combination with coveJ^ 

 density, account for 83 percent of the variance. onomation with cover 



The regression equation for sheet erosion on this study area is: 



y - 0.858 - 0.176^ - 1.81/l2 . 0.117L + O.QSUAL - 5.89F + 0.0193(7 



txon is based on 79 plots and has a standard error oHsuLte 1/1.17^^ 4). """" 



^^^J^^^^^^^J^^ - .f»^°":ran°^addjLna: 



at it^L""''''^' of figure 5 are based on the above equation with organic matter content 

 at Its average of 6 percent and slope gradient at its average of 20 percent Correction 



values in f?on . K ^'■^^"^^ ''^"^^ '^^"^^"t variation, the soil erosion 



of n percfr the H r ^^''^^''^^ ^y these factors. At an o;ganic matterc'ntent 

 if oLln^ ll^r ^'^"^^ one-half that indicated by figure 5 • but 



figure 5 In 'L' " ' P^'""'' "-"^^^^ ^^"^-^ ^hat shown in 



figure 5. In like manner, corrections for slope can be obtained from table 1 



e 2. --Correction factors for organic matter content in 

 the surface 2 inches of soil on the Davis County 

 Experzmental Watershed 



Organic matter 

 {°o by weight) 



Correction 

 factor 



[~ — 



Organic matter 

 ("o by weight) 



Correction 

 factor 



1 



1 .97 



7 



.87 



2 



1.72 



8 



. 76 



3 



1.50 



9 



.67 



4 



1.31 



10 



.58 



5 



1.15 



11 



.51 



6 



1.00 



L 



.44 



8 



