Eupatorium perfoliatum L.

Stems 4–15 dm, conspicuously crisp-villous with long spreading hairs; lvs opposite (very rarely ternate), broad-based and strongly connate-perfoliate, tapering gradually to the acuminate tip, crenate-serrate to the base, 7–20 × 1.5–4.5 cm, sparsely pubescent or subglabrous above, more evidently hairy beneath; infl flat-topped; invol 4–6 mm, its bracts imbricate in ca 3 series, the outer less than half as long as the inner, mostly obtuse, the inner more acuminate and often pale distally; fls 9–23 per head, dull white; 2n=20. Moist or wet low grounds; N.S. and Que. to n. Fla., w. to N.D., Neb., Okla., and Tex. July–Oct. Estuarine plants from Me. and Que. avg narrower-lvd than var. perfoliatum (as described above) and have a sparser, shorter, and stiffer pubescence; these are var. colpophilum Fernald & Griscom. Forms with purple fls, form with ternate lvs, and forms with the lvs not connate have been observed.

Moist, low ground, marshes, roadsides, swamps, wet pastures; at elevations up to 500 metres, sometimes higher. Wet woods, scrub, fens and damp grassland. Sandy soils in Texas.

The ash from the burnt roots is sprinkled like salt to flavour foods.

Can be grown by divisions or seedlings.