Estimation of Organic Matter in Atlantic Coastal Plain Soils With a Color‐Difference Meter1

Reflectance (L on L,aL,bL scale), determined with a color‐difference meter, was compared to the WalkleyBlack method as a measure of organic matter concentration in the surface horizons of 96 Coastal Plain soils. Reflectance values were highly correlated (r = 0.89) with soil organic matter (determined by the Walkley‐Black method) within the O to 5% range. On these soils, organic matter can be predicted from reflectance by the equation = 16.03 − 0.53X 4. 0.01X2. The procedure is faster and more economical than other methods for estimating soil organic matter.