Eutrochium maculatum

(Linnaeus) E. E. Lamont

Sida 21: 902. 2004.

Common names: Spotted joepyeweed eupatoire maculée
Basionym: Eupatorium maculatum Linnaeus Cent. Pl. I, 27. 1755
Synonyms: Eupatoriadelphus maculatus (Linnaeus) R. M. King & H. Robinson Eupatorium purpureum subsp. maculatum (Linnaeus) Á. Löve & D. Löve Eupatorium purpureum var. maculatum (Linnaeus) Voss Eupatorium trifoliatum var. maculatum (Linnaeus) Farwell
Treatment appears in FNA Volume 21. Treatment on page 475. Mentioned on page 476.

Plants 60–200 cm. Stems usually purple-spotted, sometimes uniformly purple, usually solid, sometimes hollow near bases, glabrous proximally to densely puberulent throughout, glandular-puberulent distally. Leaves in (3s–)4s–5s(–6s); petioles 5–20 mm, glabrous or pubescent; blades pinnately veined, lance-elliptic to lanceolate or lance-ovate, mostly (6–)8–23(–30) × (1.5–)2–7(–9) cm, bases gradually or abruptly tapered, margins sharply serrate or doubly serrate, abaxial faces gland-dotted and densely pubescent to glabrate, adaxial faces sparingly hairy or glabrous. Heads in flat-topped, corymbiform arrays. Involucres often purplish, 6.5–9 × 3.5–7 mm. Phyllaries glabrous or densely pubescent. Florets (8–)9–20(–22); corollas purplish, 4.5–7.5 mm. Cypselae 3–5 mm. 2n = 20.



Alta., B.C., Man., N.B., N.S., Nfld. and Labr. (Nfld.), Ont., P.E.I., Que., Sask., Ariz., Colo., Conn., Idaho, Ill., Ind., Iowa, Kans., Maine, Mass., Mich., Minn., Mo., N.C., N.Dak., N.H., N.J., N.Mex., N.Y., Nebr., Ohio, Pa., S.Dak., Utah, Va., Vt., W.Va., Wash., Wis., Wyo.


Varieties 3 (3 in the flora).

Eutrochium maculatum has the widest geographic distribution and greatest morphologic variability among species in the genus. The three varieties recognized here show intergradation where the ranges overlap.

Selected References



1 Stems densely puberulent throughout; leaves densely pubescent on abaxial faces, relatively thick; mostly w of Mississippi River Eutrochium maculatum var. bruneri
1 Stems glabrous proximally, puberulent among heads; leaves usually glabrate (seldom strongly puberulent) on abaxial faces, relatively thin; mostly e of Mississippi River > 2
2 Distalmost whorls of leaves subtending heads equaling or surpassing arrays of heads; maritime Canada, adjacent New England to ne Minnesota, n Michigan, and s Ontario Eutrochium maculatum var. foliosum
2 Distalmost whorls of leaves subtending heads not equaling arrays of heads; Newfoundland to sw Ontario, s to n and w New England, Pennsylvania, North Carolina, Ohio, Indiana, Illinois, and Iowa Eutrochium maculatum var. maculatum
... more about "Eutrochium maculatum"
Eric E. Lamont +
(Linnaeus) E. E. Lamont +
Eupatorium maculatum +
Spotted joepyeweed +  and eupatoire maculée +
Alta. +, B.C. +, Man. +, N.B. +, N.S. +, Nfld. and Labr. (Nfld.) +, Ont. +, P.E.I. +, Que. +, Sask. +, Ariz. +, Colo. +, Conn. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, Maine +, Mass. +, Mich. +, Minn. +, Mo. +, N.C. +, N.Dak. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, Nebr. +, Ohio +, Pa. +, S.Dak. +, Utah +, Va. +, Vt. +, W.Va. +, Wash. +, Wis. +  and Wyo. +
Eupatoriadelphus maculatus +, Eupatorium purpureum subsp. maculatum +, Eupatorium purpureum var. maculatum +  and Eupatorium trifoliatum var. maculatum +
Eutrochium maculatum +
Eutrochium +
species +