Taprooted annual 2-6 dm, hispid-setose and hispidulous; lower lvs petiolate, with broadly elliptic or ovate to oblanceolate blade 3-11 נ2-6 cm, the others progressively reduced and the upper often sessile and clasping; pedicels 1-4 cm; sep densely bristly, 1-1.5 cm in fr; cor 2 cm wide; anthers dark, 5-9 mm, the linear appendages 3 mm; nutlets subcylindric, 4-5 mm, rough and wrinkled; 2n=16. Native of Europe, sometimes cult., and established as a casual weed here and there in our range. May-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.