Eupatorium perfoliatum

Linnaeus
Sp. Pl. 2: 838. 1753.
Common names: Common boneset eupatoire perfoliée
Endemic
Synonyms: Eupatorium chapmanii Small Eupatorium perfoliatum var. colpophilum Fernald & Griscom Eupatorium perfoliatum var. cuneatum Engelmann
Treatment appears in FNA Volume 21. Treatment on page 471. Mentioned on page 463, 467, 469, 472, 474.

Perennials, 40–100+ cm. Stems (from short caudices) single, sparsely branched distally, puberulent throughout. Leaves usually opposite (sometimes whorled); sessile; blades pinnately nerved, oblong (tapering toward apices), 50–150+ × 15–40 mm, bases connate-perfoliate, margins serrate, apices acute, faces pilose, gland-dotted (abaxial), glabrate, not gland-dotted (adaxial). Heads in corymbiform arrays. Phyllaries 7–10 in 1–2 series, oblong, 2–4.5 × 0.6–1 mm, apices (whitish) acute to acuminate, abaxial faces villous or puberulent, gland-dotted. Florets 7–11; corollas 2.5–3 mm. Cypselae 1.5–2 mm; pappi of 20–30 bristles 3–3.5 mm. 2n = 20.


Phenology: Flowering Aug–Oct.
Habitat: Moist, low ground, marshes, roadsides, swamps, wet pastures
Elevation: 10–500+ m

Distribution

V21-1178-distribution-map.gif

Man., N.B., N.S., Ont., P.E.I., Que., Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis.

Discussion

Eupatorium perfoliatum is both distinctive, with its perfoliate leaf bases, and extraordinarily widespread. Hybrids between E. perfoliatum and other species of Eupatorium have been reported. The name E. resinosum var. kentuckiense Fernald is based on hybrids between E. perfoliatum and E. serotinum (= E. ×truncatum Muhlenberg ex Willdenow). Eupatorium perfoliatum var. colpophilum refers to populations characterized by narrower, more leathery leaves found in the extreme northeastern portion of the range.

Selected References

None.

Lower Taxa

None.

... more about "Eupatorium perfoliatum"
Kunsiri Chaw Siripun +  and Edward E. Schilling +
Linnaeus +
Common boneset +  and eupatoire perfoliée +
Man. +, N.B. +, N.S. +, Ont. +, P.E.I. +, Que. +, Ala. +, Ark. +, Conn. +, Del. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, N.H. +, N.J. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Vt. +, Va. +, W.Va. +  and Wis. +
10–500+ m +
Moist, low ground, marshes, roadsides, swamps, wet pastures +
Flowering Aug–Oct. +
Eupatorium chapmanii +, Eupatorium perfoliatum var. colpophilum +  and Eupatorium perfoliatum var. cuneatum +
Eupatorium perfoliatum +
Eupatorium +
species +