R.I. Gen. Laws § 20-18-1

The director may, in the name and for the use of the state, and subject to the approval of the state properties committee, acquire by gift, lease, purchase, or easement, land within the state for the purpose of protecting, conserving, cultivating, or propagating any species of wildlife, plant, or animal. The director may, with the consent of the owner of the land, control any land suitable with character and situation for those purposes. Any land so acquired or controlled by the department of environmental management shall be posted conspicuously and designated as a state park or management area.