Tenn. Code § 11-14-110
Within the boundaries of any Class I or Class II area included within the system, except those belonging to local governments, the commissioner may acquire, on behalf of the state of Tennessee, lands in fee title, or if applicable, and preferably, interest in land in the form of conservation easements. Easements should especially be sought in establishment of trails or other narrow, elongated or extensive land uses. Acquisition of land in fee or of any interest therein may be by donation, purchase with donated or appropriated funds, exchange, or otherwise. In acquiring property or property interests, as herein defined, the commissioner shall have the powers set forth in title 29, chapter 16, as heretofore or hereinafter amended, or under any other applicable statutory provisions now in force or hereafter enacted for the exercise of the power of eminent domain. No area shall be added to this part except by an act of the general assembly.
T.C.A. § 11-14-110