Ann. Sci. Nat., Bot., sér. 3, 5: 43. 1846.
Plants winter-annual or biennial, glabrous; taproots 1–4(–6) dm. Stamens (2 or)4. Fruits: hypanthia ridges extended into thin wings, 0.5 mm wide; sepals tuberculose-thickened proximally.
Phenology: Flowering Mar–Jun; fruiting Apr–Jul.
Habitat: Sandy and rocky soil, prairies, oak savannas, oak woodlands, disturbed areas (pastures, roadsides), often locally moister sites
Elevation: 0–500 m
Ont., Ark., Iowa, Kans., N.Y., Okla., S.C., Tex.
The eastern records (Ontario, Iowa, Massachusetts, New York, and South Carolina) all appear to represent adventives or non-persistent waifs. A record from Maryland (J. B. S. Norton and R. G. Brown 1946) is plausible; no specimen is known to the author.