K is the ridge roughness factor. C is the climatic factor. All climatic factor values are expressed as a percentage of the value established at Garden City, Kansas. Garden City, Kansas was the location of early research in the WEQ and established the standard for climatic factors against which the other locations are measured. L is the unsheltered distance across an erodible field, measured along the prevailing wind erosion direction.
V is the vegetative cover factor.
The USLE factors are explained in the U.S. Department of Agriculture Handbook 537. The WEQ factors are explained in a paper by N.P. Woodruff and F.H. Siddaway, 1965. The FOTG is available for review in each NRCS field office. The values vary across the country to correspond to differences in climate, soil types, and topography. USLE has been used to develop conservation plans and revisions and to conduct status reviews.