Distribution: Occurring in the Olympic Mountains and North Cascades in Washington; Alaska south to Washington, Nevada, east to the Rocky Mountains; east across northern Canada to Greenland; northern Europe.
Habitat: Subalpine and alpine meadows, often in rock crevices and outcroppings.
Conservation Status: Not of concern
Annuals or short-lived perennials, branched at base, usually bearing scapes; stems generally 0.3-1.1 dm, unbranched or uncommonly branched distally, glabrous throughout or rarely pubescent PROXIMALLY; trichomes simple, 0.3-0.7 mm.
Basal leaves form rosettes, petioles ciliate, blades oblanceolate or obovate, 0.5-2.5 cm long and 2-4 mm broad, margins entire or rarely finely toothed, occasionally ciliate, glabrous above and beneath or sparsely pubescent, with simple trichomes and 2-rayed trichomes less than 1 mm; cauline leaves usually absent, sometimes 1, sessile, ovate or oblong, margins entire, glabrous above and beneath.
Inflorescence racemose, generally 4-15 flowered, no bracts, elongated in fruit; rachis somewhat flexuous or straight, glabrous; pedicels spreading horizontally, generally straight, 3-8 mm and slightly shorter than fruit, glabrous; sepals 4, green or light purple, ovate, 1.5-2.5 mm long and 0.5-1 mm broad, glabrous; petals 4, yellow, turning white with age, oblanceolate, usually 1.5-2.5 mm long and 0.5-1 mm broad; anthers 0.15-0.25 mm, ovate.
Siliques 5-10 mm long and 1.5-2.5 mm broad, generally lanceolate, plane, flattened; valves glabrous; ovaries generally contain 16-24 ovules; seeds elliptic, 0.7-0.8 mm long and 0.4-0.5 mm broad.