Mich. Comp. Laws § 123.778

Sec. 48. The court commissioners shall determine whether it is necessary to take for public use or benefit the property described in the petition, and if so, shall appraise the damages to be paid as compensation for each piece or parcel of property, and shall report such decision in writing, signed by them or a majority of them, at or before the time fixed for that purpose, but it shall not be necessary for the court commissioners to report on all of the property at one time.