Eupatorium serotinum

Michaux

Fl. Bor.-Amer. 2: 100. 1803.

Common names: Lateflowering thoroughwort
Treatment appears in FNA Volume 21. Treatment on page 473. Mentioned on page 463, 465, 466, 468, 470, 471, 472, 474.
Revision as of 20:33, 16 December 2019 by FNA>Volume Importer

Perennials, 50–150+ cm. Stems (from short caudices) single, sparsely to densely branched distally, pubescent throughout (sometimes reddish to purplish). Leaves opposite; petiolate (petioles 10–25 mm); blades ± 3-nerved, lanceolate, 20–90+ × 5–40 mm, bases rounded to slightly oblique, margins entire or serrate, apices acute, faces puberulent, gland-dotted. Heads in corymbiform arrays. Phyllaries 8–12 in 1–2 series, elliptic to oblong, 1–3 × 0.5–1 mm, apices slightly rounded to acute, abaxial faces puberulent, gland-dotted. Florets 9–15; corollas 2.5–3 mm. Cypselae 1–1.5 mm; pappi of 20–30 bristles 2–2.5 mm. 2n = 20.


Phenology: Flowering Aug–Oct.
Habitat: Moist or dry, open sites, roadsides
Elevation: 10–400+ m

Distribution

V21-1188-distribution-map.gif

Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Tex., Va., W.Va., Wis.

Discussion

Eupatorium serotinum has a wide distribution and is often abundant where it occurs. It includes only sexual, diploid populations. It is known to hybridize with E. perfoliatum. An introduction of E. serotinum in southeastern Ontario apparently is local and may not have persisted.

Selected References

None.

Lower Taxa

None.
... more about "Eupatorium serotinum"
Kunsiri Chaw Siripun +  and Edward E. Schilling +
Michaux +
Lateflowering thoroughwort +
Ala. +, Ark. +, Conn. +, Del. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, N.J. +, N.Y. +, N.C. +, Ohio +, Okla. +, Pa. +, R.I. +, S.C. +, Tenn. +, Tex. +, Va. +, W.Va. +  and Wis. +
10–400+ m +
Moist or dry, open sites, roadsides +
Flowering Aug–Oct. +
Fl. Bor.-Amer. +
Compositae +
Eupatorium serotinum +
Eupatorium +
species +