Tenn. Code Ann. § 12-1-107

In the event it becomes necessary to so acquire any land under authority of §§ 12-1-106 — 12-1-108, the commissioner of the department seeking to have the same acquired shall make a request in writing to the governor, giving in detail the location of the land sought to be acquired, its probable cost, the necessity for the acquisition and all other information the commissioner deems material, and if the governor approves the request for acquisition, the commissioner shall then be authorized to acquire the land.