Abstract: The tree ring is a one-piece device formed from a planar member shaped as an annulus that defines a central opening. Disposed along an outer edge of the planar member is a raised wall for retaining mulch, soil nutrients, and the like in the immediate region surrounding a tree. The raised wall extends to an upper portion to form an arcuate, inverted U-shaped lip directed away from the central opening. When the tree is disposed through the central opening, the wall and planar member cooperate to retain mulch material about the base of a tree. The upper portion lip limits encroachment of grass and weeds upon the tree while providing an esthetically pleasing appearance. The lip is designed to provide sufficient clearance so that a lawn mower, string trimmer, and the like, may be run proximate to the device without disturbing the tree or surrounding mulch.