Any lot of tobacco which needs to be resorted or otherwise reworked to prepare it properly for market, including: (a) Tobacco which is so mixed that it cannot be classified properly in any grade of the type, because the lot contains a substantial quantity of two or more distinctly different grades which should be separated by sorting; (b) tobacco which contains an abnormally large quantity of foreign matter or an unusual number of muddy or extremely dirty leaves which should be removed; and (c) tobacco not packed straight or otherwise not properly prepared for market. (See Rule 22, § 29.2413 .)
7 C.F.R. §29.2293