Clematis occidentalis

(Hornemann) de Candolle

Prodr. 1: 10. 1824.

Common names: Purple clematis clématite occidentale
Endemic
Basionym: Atragene occidentalis Hornemann Hort. Bot. Hafn. 2: 520. 1815
Treatment appears in FNA Volume 3.
Revision as of 20:55, 24 September 2019 by FNA>Volume Importer

Stems viny, climbing or trailing (plants scarcely viny perennials in var. dissecta). Leaf blade 1-ternate (or terminal leaflet sometimes ternate in var. dissecta), ± firm but not succulent; leaflets lance-ovate to triangular or suborbiculate, lobed or unlobed, margins entire or toothed. Flowers: sepals violet-blue, reddish violet, or white, lanceolate to ovate or elliptic-oblong.

Distribution

North America.

Discussion

Varieties 3 (3 in the flora).

Selected References

None.

Key

1 Leaflets lobed or unlobed, margins entire or crenate-serrate (or terminal leaflet sometimes ternate); stems tufted or, if viny, up to 0.5(–1.5) m. Clematis occidentalis var. dissecta
1 Leaflets unlobed or some 1–3-lobed, margins entire or shallowly serrate; stems ± viny, climbing or trailing, 0.25–3.5 m. > 2
2 Sepals reddish violet, rounded-mucronate to nearly acuminate. Clematis occidentalis var. occidentalis
2 Sepals violet-blue to pale blue, rarely white, usually distinctly acuminate. Clematis occidentalis var. grosseserrata