Mich. Comp. Laws § 457.227

Sec. 7. The management and control of the business, affairs and property of such corporation shall be vested in said board of trustees, and said board shall have power to borrow any money and cause to be made and issued any bonds and mortgages authorized by section 4 of this act. Said trustees shall appoint from their own number a president, secretary and treasurer, who shall perform the duties of their respective offices in accordance with the rules and regulations prescribed by the board of trustees.