Mich. Comp. Laws § 290.153

Sec. 3. It shall be unlawful for any person, firm, association, organization, or corporation or agent, representative or assistant of any person, firm, association, organization or corporation, to pack for sale, expose for sale, or sell, transport, deliver or consign, or have in possession for sale, transport, delivery or consignment in interstate or intrastate commerce, potatoes prepared for market which are not graded or designated to meet the requirements of the grade or designation, which shall be 1 of the grades or designation listed in section 1.