Canad. J. Bot. 84: 279. 2006.
Perennials; (caudex usually branched, rarely simple, with persistent petiolar remains); glabrous throughout or sparsely to moderately pubescent, trichomes simple and short-stalked, forked, (to 0.5 mm). Stems often several from base (caudex), erect, ascending, or decumbent, unbranched or branched (few) distally, 0.5–2(–3) dm, glabrous or sparsely pubescent distally. Basal leaves: petiole 0.5–2 cm, (ciliate or glabrous); blade (fleshy), oblanceolate to spatulate, 0.5–2 cm × 2–6 mm, margins entire or dentate, (not ciliate), apex obtuse or acute, surfaces pubescent or glabrous. Cauline leaves [(1–)2–4(–6)] sessile; blade oblong to oblanceolate, 0.7–1.8(–2.5) cm × 2–5 mm, (base not auriculate), margins usually entire, rarely dentate, (apex obtuse or acute, surfaces glabrous or sparsely pubescent). Fruiting pedicels ascending to divaricate, 5–10(–12) mm, (glabrous). Flowers: sepals 1.7–3 mm, lateral pair not saccate basally; petals white, usually oblanceolate, rarely spatulate, 4–5 × 1–2 mm; filaments 1.7–3 mm. Fruits (suberect to divaricate), straight, smooth, terete or slightly flattened, (0.8–)1–2(–2.8) cm × 1.5–2.2(–2.5) mm; valves each with obscure midvein; ovules 30–54 per ovary; style 0.4–0.8 mm. Seeds (sometimes sub-biseriate), reddish brown, narrowly oblong, 0.9–1.1 mm, pointed distally; cotyledons incumbent. 2n = 32.
Phenology: Flowering Jun–Aug.
Habitat: Sandy beaches, gravel, flats of streambeds
Elevation: 0-1500 m
Greenland, Man., Nfld. and Labr. (Labr.), Nunavut, Ont., Que., Sask.