Annual or biennial. Stems erect, 8–50 cm, usually branched above. Basal leaves petiolate, narrowly oblanceolate with sinuate to shallowly lobed margins, withering early. Stem leaves sessile. Vestiture of sparse, short, simple hairs. Flowers white; petals ca. 1 mm long or lacking; stamens 2. Fruit broadly obovate, glabrous to pubescent, 2.5–3.5 mm long, notched; style lacking; pedicels spreading, glabrous or puberulent, 1.5–3.5 mm long. (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX
In Montana we have varieties densiflorum
(A. Nelson) Thell., and ramosum
(A. Nelson) Thell.
Disturbed soil of fields, grasslands, steppe, open forest; plains, valleys, montane (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX