Clematis vitalba
Sp. Pl. 1: 544. 1753.
Stems climbing with tendril-like petioles and leaf-rachises, to 12 m. Leaf-blade pinnately 5-foliolate; leaflets cordiform, 8 × (2-) 3-5 (-6) cm, margins entire to regularly crenate or dentate; surfaces abaxially minutely pubescent on veins, adaxially glabrous. Inflorescences axillary and terminal, (3-) 5-22-flowered cymes. Flowers bisexual; pedicel 1-1.5 cm, slender; sepals widespreading, not recurved, white to cream, elliptic or oblanceolate to obovate, ca. 1 cm, length ca. 2 times width, abaxially and adaxially tomentose; stamens ca. 50; filaments glabrous; staminodes absent; pistils 20 or more. Achenes nearly terete, not conspicuously rimmed, densely pubescent; beak ca. 3.5 cm.
Phenology: Flowering summer (Jun–Aug).
Habitat: Roadsides, waste ground, secondary growth
Elevation: 0-100 m
Distribution
B.C., Ont., Maine, Oreg., Wash., native to Europe, n Africa
Discussion
Clematis vitalba is naturalized in only a few sites in eastern North America and northwestern Oregon to the Puget Sound.
Selected References
None.