Mich. Comp. Laws § 3.454c

Sec. 4c. If the United States offers to this state a relinquishment of legislative jurisdiction over lands within the Pictured Rocks national lakeshore, the governor may accept on behalf of this state the legislative jurisdiction offered to be relinquished. The governor shall indicate his or her acceptance of relinquished legislative jurisdiction by a writing addressed to the head of the appropriate department or agency of the United States. The acceptance is effective when deposited in a United States post office or mailbox.