Erect, to 1 m, ±canescent, lvs lanceolate to oblanceolate, pinnate with entire to lobed or deeply pinnatifid segments; fls 3 mm wide; mature racemes dense, the frs overlapping, the pedicels 3-6 mm, narrowly ascending; frs appressed to the rachis, linear, 5-12 נ0.7-1.3 mm; septum without veins; seeds in each locule 4-10, in one row; 2n=14, 28, 42. Throughout w. N. Amer., from nw. Can. to n. Mex., e. to Minn., Ont., and e. Que. June, July. Our pls, as here described, are var. richardsonii. (Sophia richardsoniana; S. hartwegiana; Sisymbrium incisum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.