Annual, glabrous below, glandular-hairy above. Stems erect to ascending, 10–40 cm. Leaves fascicled, appearing whorled, 1-veined; stipules scarious, white, 1 mm long. Inflorescence glandular-hairy, terminal, few-flowered cymes, or solitary and axillary. Flowers: sepals 5, 2–3 mm long, united at the base, margins scarious; petals 5, white with entire margins, shorter than the calyx; stamens 2 to 10; styles 5. Capsule ovoid, 3–5 mm long, opening by 6 slits (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).