Contains 19 accepted taxa overall.
Characteristics
Classification
Citation
EUPATORIUM Linnaeus, Sp. Pl. 836. 1753.
-
TYPE: Eupatorium cannabinum Linnaeus Lectotypified by Britton & A. Brown, Ill. Fl. N. U.S., ed. 2. 3: 355. 1913.
Species
| Scientific Name | Common Name | Herbarium Specimens | Status | Photos |
|---|---|---|---|---|
| Eupatorium album | WHITE THOROUGHWORT | Native FAC (DEP) | ||
| Eupatorium altissimum | TALL THOROUGHWORT | Native FAC (DEP) | ||
| Eupatorium capillifolium | DOGFENNEL | Native FACU (NWPL) AD (WAP) FAC (DEP) | ||
| Eupatorium compositifolium | YANKEEWEED | Native FAC (NWPL) FAC (DEP) | ||
| Eupatorium hyssopifolium var. hyssopifolium | HYSSOPLEAF THOROUGHWORT | Native FAC (DEP) | ||
| Eupatorium hyssopifolium var. laciniatum | HYSSOPLEAF THOROUGHWORT | Native | ||
| Eupatorium leptophyllum | FALSEFENNEL | Native FACW (NWPL) OD (WAP) OBL (DEP) | ||
| Eupatorium leucolepis | JUSTICEWEED | Native FACW (NWPL) FACW (DEP) | ||
| Eupatorium linearifolium | WAXY THOROUGHWORT | Native FAC (DEP) | ||
| Eupatorium mikanioides | SEMAPHORE THOROUGHWORT | Native FACW (NWPL) FACW (DEP) | ||
| Eupatorium mohrii | MOHR'S THOROUGHWORT | Native FACW (NWPL) AD (WAP) FAC (DEP) | ||
| Eupatorium perfoliatum | COMMON BONESET | Native FACW (NWPL) FACW (DEP) | ||
| Eupatorium petaloideum | Native | |||
| Eupatorium pilosum | ROUGH BONESET | Native FACW (NWPL) FAC (DEP) | ||
| Eupatorium rotundifolium | ROUNDLEAF THOROUGHWORT; FALSE HOREHOUND | Native FAC (NWPL) FAC (DEP) | ||
| Eupatorium semiserratum | SMALLFLOWER THOROUGHWORT | Native FACW (NWPL) FAC (DEP) | ||
| Eupatorium serotinum | LATEFLOWERING THOROUGHWORT | Native FAC (NWPL) AD (WAP) FAC (DEP) | ||
| Eupatorium x anomalum | FLORIDA THOROUGHWORT | Native FAC+ (NWPL) FAC (DEP) | ||
| Eupatorium x pinnatifidum | Native FAC (DEP) |
Identification Key
1. Leaves pinnatifid, or pinnately or ternately lobed, lobes linear to linear-lanceolate, margins entire (Traganthes group)
1. Leaves simple, not lobed, margins crenate, entire, laciniate, serrate, or serrulate (core Eupatorium group)
1. (Key A) Leaf blades or lobes linear-lanceolate, to 4 mm wide; heads in subcorymbiform to subpaniculiform arrays; florets 7-9
1. Leaf blades or lobes usually linear and <3 mm wide; heads in paniculiform arrays; florets usually 5
2
2. Stems glabrous; heads secund on branches
2. Stems puberulent; heads not secund on branches
3
3. Leaf blades or lobes 0.2-0.5(1) mm wide (margins strongly revolute); phyllaries usually glabrate or glabrous, usually not gland-dotted
3. Leaf blades or lobes 0.5-2.5(4) mm wide; phyllaries usually puberulent (mostly on midveins), usually gland-dotted
1. (Key B) Petioles of larger leaves 5-30 mm long
2
1. Petioles 0-5(10) mm long
3
2. Leaf blades deltate to rhombic, to 6(8) cm long, coriaceous-subsucculent, margins generally crenate-undulate; florets 5
2. Leaf blades lanceolate, to 15 cm long, chartaceous to membranaceous, margins mostly serrate to serrate-crenate; florets 9–15
3. Leaf bases connate-perfoliate
3. Leaf bases not connate-perfoliate
4
4. Phyllaries with a white filiform to acuminate apex
5
4. Phyllaries with an acute, obtuse, to rounded, green to white apex
7
5. Leaves 4-10(15) mm wide, secondary veins weak or obscure
5. Leaves (5)10-45 mm wide, secondary veins conspicuous throughout
6
6. Leaves usually gland-dotted; phyllaries puberulent to villous (at least toward bases and on midveins), gland-dotted
6. Leaves eglandular or sparsely gland-dotted; phyllaries glabrous, eglandular
7. Leaf blades usually broadest below the middle, bases usually broadly cuneate, rounded, subcordate, or truncate
8
7. Leaf blades usually broadest near or above the middle, bases cuneate to attenuate
9
8. Leaf blades elliptic, lanceolate, or lance-ovate, mostly 1.6-2.5 times longer than wide; inflorescence branches alternate; phyllary glands nearly colorless
8. Leaf blades usually ovate to deltate, mostly 1-1.6(2) times longer than wide; proximal inflorescence branches often opposite to subopposite; phyllary glands yellow to golden
9. Leaves strongly 3-nerved from the base to near the apex
9. Leaves 1-nerved, pinninerved, or weakly 3-nerved
10
10. Leaves usually in whorls of 3s or 4s, sometimes opposite, blades linear, (6)8-40 times longer than wide
11
10. Leaves usually opposite, occasionally whorled, blades elliptic, lance-elliptic, lance-oblong, oblanceolate, or oblong, 2.5-16 times longer than wide
12
11. Leaves 2-5 mm wide, margins usually entire to obscurely serrulate
11. Leaves 5-15 mm wide, margins usually laciniately toothed
12. Leaf blade upper surface glabrous or glabrate
13
12. Leaf blade upper surface finely puberulent or villous
14
13. Leaves usually recurved, the blades 2-8 cm long, 0.5-1(2) cm wide
13. Leaves usually spreading to ascending, the blades 15-50 cm long, (0.5)1–2 cm wide
14. Plant usually with some branches near the base; leaf blades mostly 2-3.5(4.5) cm long, margins weakly serrate to subentire; phyllaries lanceolate, larger ones 3-5 mm long; corollas 3-3.5 mm long
14. Plant usually unbranched below the middle; leaf blades (3)5-7 cm long, margins usually serrate; phyllaries elliptic, larger ones 2.5-3 mm long; corollas 2.5-3 mm long
Genus Synonyms
| Synonym | Full Citation | Basionym | Type |
|---|---|---|---|
| Chone | Chone Dulac, Fl. Hautes-Pyrénées 512. 1867. | TYPE: Chone heterophylla Dulac, nom. illegit. (Eupatorium cannabinum Linnaeus) = Eupatorium Linnaeus 1753, by lectotypification. | |
| Cunigunda | Cunigunda Bubani, Fl. Pyren. 2: 273. 1899. | TYPE: Cunigunda vulgaris Bubani, nom. illegit. (Eupatorium cannabinum Linnaeus) = Eupatorium Linnaeus 1753, by lectotypification. | |
| Traganthes | Traganthes Wallroth, Sched. Crit. 1: 456. 1822. | TYPE: Artemisia capillifolia Lamarck | |
| Uncasia | Uncasia Greene, Leafl. Bot. Observ. Crit. 1: 13. 1903. | TYPE: Uncasia perfoliata (Linnaeus) Greene (Eupatorium perfoliatum Linnaeus) |