Annual with prostrate to spreading or ascending stems 2-8 dm; lvs stiff, sessile, linear to narrowly lanceolate, 2-4 cm, scabrous, aristate; stipules 4-10 mm, with a short sheath and 5-8 ascending or erect setaceous bristles; fls in many of the upper axils; sep 4, lanceolate, 2 mm; cor funnelform, white to pale purple, 5-6 mm; style capitate; fr obovoid, hairy, 2.5-6 mm, crowned by the persistent sep; 2n=28. Dry or sandy soil, often weedy; s. N. Engl. to s. Wis., Io. and Kans., s. to trop. Amer. June-Sept. (Diodella t.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.