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Soil - Irregular spots of different colors that vary in number and size. Mottling generally indicates poor aeration and impeded drainage. Descriptive terms are as follows abundance few, common, and many, size fine, medium, and coarse; and contract faint, distinct, and prominent. The size measurements are of the diameter along the greatest dimension. Fine indicates less than 5 mm (about 0.2 inch); medium, from 5 to 15 mm (about 0.2 to 0.6 inch); and coarse, more than 15 mm (about 0.6 inch).