2002-05-13_PERMIT FILE - C1981041 (13)

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size. The .erms used and described are below (USDA, '95i): Contrast. iontrast may be .described as faint, distinct, or ^.rominent as • follows: - Faint: indistinct mottles are evident and recocnizable only with close examination. Soil colors in both the matrix and mottles have closely related 'Hues and chromas. - Distinct: Althouch Hat striking, the mottles are readily seen. The hue, value, and chroma of the matrix are easily distinguished from those of the :mottles. They may vary as much as one or ttiro hues or several units in chroma or value. The pattern may be one of a continucus matrix o-rith mottles or one of mixtures of t~rro or more colors. - Prominent: The conspicuous mott]es are obvious and mottling is one of the outstanding features of the horizon. Hue, chroma, and value may be several units apart. The pattern may be one of a continuous matrix • with contrasting mottles or one of mixtures of two or more colors. Abundance. Abundance of mottles can be indicated in three general classes as: few, common, and many, based upon the relative amount of mottled surface in the unit area of the exposed sail horizon, as follows: - Few: Mottles occupy less than about 2 percent of the exposed surface. - Common: Mottles occupy about 2 to 20 percent of the exposed surface. - Many: Mottles occupy mare than 20 percent of the exposed surface. This last class can be further subdivided according to whether (a) the mottles set in a definite matrix or (b) there is no clear matrix color. Size. Size refers to the approximate diameters of individual mottles. Three relative size classes can be used as follows: - Fine: tlottles less than 5 mmi. in diameter along the greatest dimension. • - Medium: Mottles range between 5 and 15 mm. in diameter along the greatest dimension. - Coarse: Mottles are greater than 15 mm. in diameter along the greatest dimension.