Coarse, fragrant perennial 5-15 dm; stem strigose above; lvs silvery-strigose or subsericeous when young, later ±glabrate, crenate, sometimes with a few reduced basal pinnae, the basal with elliptic or broadly oblanceolate blade 10-25 נ2.5-8 cm on a petiole of ca equal length, the cauline smaller, numerous, sessile or nearly so, seldom over 10 cm; heads numerous in a corymbiform infl, the disk 4-7 mm wide; rays wanting, or occasionally present, white, and well under 1 cm; 2n=18, 54. Roadsides and other waste places; native of s. Europe and the Orient, occasionally intr. or escaped in our range. Aug.-Oct. Generic position uncertain. (Tanacetum b.; Balsamita major)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.