Abstract: A clamp and system which incorporates the clamp for laterally supporting the stems of plants and the trunks of small tree saplings. The clamp is attachable to horizontal and vertical support structure such as a post, wire, rod, and larger walls or the like. The clamp has an arcuate body with opposing concave and back surfaces, the concave surface shaped to receive and partially surround a plant stem or tree trunk. Disposed from the back surface or at each end of the arcuate body are a pair of opposing spaced clips adapted to lockably receive an elastic member such as a ring or length of cord. These clips may also serve as retainers for another elastic ring which cushions the plant stem or tree trunk against the concaved surface. The arcuate body includes a mounting post extending from the back surface between the clips having a longitudinal aperture therethrough for receiving a hammered or threaded fastener to be embedded into a suitable support structure so as to secure the body thereto.