Although widespread across eastern North America, this vine is uncommon to rare in warmer or drier regions, including much of w. Ky. and c. Tenn. except close to the Mississippi Rv. In 1914, Gm noted: "found everywhere in thickets and in openings, clambering over fences, rocks and shrubs, and in the absence of support, sometimes sprawling on the ground." It remains widely scattered across north-central Ky. in richer soils, but it has become rare in more populated areas. The species may be relatively unpalatable and somestimes promoted by mammalian herbivory (e.g. Bowers 1993). Growth in cultivation is relatively slow during the initial 2-3 years. C. scandens may have been reduced due to harvesting of fruiting branches for decoration, and perhaps locally intense browsing by deer and livestock. Rabbits may also cut or consume large amounts (Todd 1927). Gradual invasion of orbiculatus could pose another threat by direct competition and genetic introgression; 2n = 46 in both species (Pooler et al. 2002). However, there have been no reports of wild hybrids in North America (Y, W). Root bark of Celastrus (and some allies in the family) contains a reddush pigment named celastrol; this is a pentacyclic triperpenoid with powerfuil physiological effects (Venkatesha & Moudgil 2016).