Polymnia canadensis L.

Coarse perennial 0.6–2 m, glabrate below, viscid-villous or stipitate-glandular above; lvs large, thin, to 3 dm, broadly oblong to ovate, pinnately few-lobed, also toothed, the petiole wingless or winged only near the blade; heads in congested cymes ending the branches, the pale yellow disk 6–13 mm wide; invol bracts lanceolate to lance-linear, narrower and often shorter than the bracts that subtend the ray-achenes; cor of pistillate fls minute and tubular, or expanded into a short, whitish ray to 10(–15) mm; achenes 3–4 mm, unequally 3-ribbed and-angled, not striate; 2n=30. Moist woods, especially in calcareous regions; Vt. and Ont. to Minn., s. to Ga. and Ark. June–Oct. (P. radiata, the radiate form)