United States, Minnesota, Cook, Rugged bedrock terrain above McFarland Lake, on the edge of the Boundary Waters Canoe Area Wilderness 16 miles north-northwest of Hovland. T64N R3E SW1/4 of SW1/4 of NW1/4 Sec. 4, N1/2 of SW1/4 of NE1/4 Sec. 5
Occasional to frequent on 15- to 60-foot, north- to northeast-facing cliffs which are scattered along ~1/2-mile of very steep mid- and upper portions of a 240-foot slope. Forming patches in crevices and on narrow ledges of diabase and sedimentary (Rove Formation) bedrock. Dry-mesic shaded settings beneath Betula cordifolia, B. papyrifera, Thuja occidentalis, Abies balsamea, and Picea mariana.
Associates include Woodsia scopulina, W. ilvensis, Dryopteris fragrans, Cystopteris fragilis, Polypodium virginianum, Campanula rotundifolia, Poa glauca.