ex Torr. &: A. Gray. (syn. O. albiflora). Stemless and tufted from a branching rootstock, silky-hairy. Leaves 20-30cm in length, of nineteen to thirty-nine elliptic silky white-hairy leaflets. Flowers white to pale yellow, often pink-tinted, rarely lilac to purple, in racemes of 15cm or more long, just above the leaves, summer. Montana and Nevada to New Mexico and Texas, in prairies to subalpine meadows. O.s. var. spicata has lemon to sulphur-yellow flowers only. See also O. halleri. [Pl.331].