Mich. Comp. Laws § 32.233

Sec. 3. Any state institution, or any city, village, township or county desiring to establish fresh air camps or to use such grounds for any other recreational or health giving purpose, may by making application to said board, be assigned space on said grounds for such purpose: Provided, however, That no camps, lodges, cottages or other buildings shall be erected thereon without permission for such erection being granted by the state military board.