Much-branched annual 2-8 dm, the branches usually alternate; lvs numerous, erect or ascending, linear, 5-20 mm; fls mostly solitary in the axils, short-pediceled; sep lance-linear, 3-6 mm, often surpassing the 3-5 mm pet; stamens 10-22; styles 3, to 1 mm; fr ovoid, 4-6 mm; seeds light to dark brown, 1 mm, coarsely and conspicuously rugose and areolate; 2n=24. Dry soil; Md. to O., Ill., Io., and se. Kans., s. to Fla. and Tex. July-Sept. (Sarothra d.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.