Distribution: In the Cascade Mountains in Washington; British Columbia south to California.
Habitat: Rocky crevices, moraines, ridges and talus slopes in alpine and sup-alpine regions.
Growth Duration: Perennial
Conservation Status: Not of concern
Grayish, mat-forming perennial from a much-branched crown, the simple stems 3-18 cm. tall, the herbage with mixed pubescence, long, soft, and simple, and shorter and freely branched.
Basal leaves 0.5-2.5 cm. long, obovate, ovate, suborbicular, or oblong; petioles slender, 1-6 cm long, pubescent with branched hairs and longer, simple hairs; cauline leaves several, alternate, reduced.
Inflorescence a bractless, flat-topped raceme, becoming elongate in fruit; pedicles ascending; sepals 4, 2-2.5 mm. long, persistent; petals 4, usually white, rarely pinkish, spatulate to obovate, 3.5-4.5 mm. long; stamens 6; style about 0.5 mm. long, stigma discoid.
Siliques ovate to oblong, 2-6 mm. long and 2-3 mm. broad, glabrous, terete or slightly flattened, the valves 1-nerved; seeds in 1 series.