For use in LRRs W, X, and Y.
A mineral layer that has dominant hue of 5Y with chroma of 3 or less, or a gleyed matrix, with 10 percent or more distinct or prominent redox concentrations occurring as pore linings with value and chroma of 4 or more. The layer occurs at a depth ≤30 cm (12 inches) from the soil surface.
User Notes: In a soil layer that has been reduced, one of the first areas where oxygen will be reintroduced is along pores and the channels of live roots. As oxidation occurs in these areas, characteristic reddish orange redox concentrations (with value and chroma of 4 or more) will be apparent along the pores and linings. These will stand out in contrast to the matrix color of the overall soil layer. First, determine if the dominant color(s) of the soil layer match the chroma 3 or less or gley colors indicated. Then break open pieces of the soil and look for reddish orange redox concentrations along pores and root linings. The occurrence of these concentrations indicates that the soil has been reduced during periods of saturation and is now oxidizing in a drier state.