Mich. Comp. Laws § 290.159

Sec. 9. The intent and purpose of this act is to regulate the sale of potatoes for table use intended for intra-state and inter-state commerce when such sale is made by the grower, dealer or distributor, or any other person either by wholesale or retail or in any other manner: Provided, however, That the provisions of this act shall not apply to the grower or his employee in the sale of potatoes grown by such grower when made direct to the consumer.