Isatis tinctoria L.
-
Authority
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
-
Family
Brassicaceae
-
Scientific Name
-
Description
Species Description - Biennial, usually single-stemmed, 5–12 dm, glabrous and glaucous; basal lvs oblanceolate, long-petioled; cauline lvs sessile, lanceolate to oblong, mostly 2–10 cm, entire or nearly so, auriculate-clasping; infl of numerous racemes, forming a large terminal panicle; fls 6 mm wide; frs drooping on short, slender pedicels, oblong to obovate, mostly 8–15 × 2.5–6 mm, thickened and corky in the center; 2n=28. Native of Europe, where traditionally cult. as the source of a blue dye; occasionally found as a weed in our range. May–July.