This rhizomatous taxon is restricted to mesic woods in cool temperate, subalpine or boreal zones of northeastern North America. In Ky. it occurs only on strongly acid soils in ravines of the Appalachian Cliff Section and in the Cumberland Mts. O. montana is close to the Eurasian O. acetosella L. and sometimes combined; 2n = 22 in both taxa (Cr).