Perianth yellow with yellowish to greenish veins. 2n = 24. Flowering summer (Jun--Sep). Rocky slopes and exposed habitats of subalpine zones; 100--1000 m; B.C. Variety flava from the Queen Charlotte Islands (Graham and Moresby islands) differs from the typical variety in floral color and is more robust with well-developed leaves that nearly always exceed the flowering or fruiting scapes (J. A. Calder and R. L. Taylor 1965).
Perianth white with greenish to purplish veins. 2n = 24, 36, 48. Flowering summer (Jun--Sep). Gravelly to rocky slopes and cliff faces or rock crevices, grassy tundra; 400--4400 m; B.C., N.W.T., Yukon; Alaska, Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wash., Wyo.; Eurasia. Variety serotina, the typical, arctic-alpine variety (T. Irmisch 1863; B. Jones and C. Gliddon 1999), is wide-ranging throughout the Northern Hemisphere (N. Woodhead 1951).