Clematis hirsutissima

Pursh

Fl. Amer. Sept. 2: 385. 1814.

IllustratedEndemic
Basionym: Coriflora hirsutissima (Pursh) W. A. Weber Phytologia 79: 65-66. 1996[1995]
Treatment appears in FNA Volume 3.

Stems erect, not viny, 1.5-6.5 dm, hirsute (sometimes sparsely so in var. hirsutissima) or densely short, soft-pubescent to nearly glabrous. Leaf blade 2-3-pinnate; leaflets often deeply 2-several-lobed, if lobed than lateral lobes usually small and distinctly narrower than central portion, leaflets or lobes linear to lanceolate, 1-6 × 0.05-1.5 cm, thin, not prominently reticulate; surfaces sparsely to densely silky-hirsute, not glaucous. Inflorescences terminal, flowers solitary. Flowers broadly cylindric to urn-shaped; sepals very dark violet-blue or rarely pink or white, oblong-lanceolate, 2.5-4.5 cm, margins narrowly expanded distally, 0.5-2 mm wide, thin, distally ± crisped, tomentose, tips obtuse to acute, slightly spreading, abaxially usually densely hirsute, occasionally moderately so. Achenes: bodies densely long-pubescent; beak 4-9 cm, plumose.

Distribution

Ariz., Colo., Idaho, Mont., N.Mex., Nebr., Okla., Oreg., S.Dak., Utah, Wash., Wyo.

Discussion

Varieties 2 (2 in the flora).

The varieties of Clematis hirsutissima, although highly dissimilar in their extreme forms, intergrade extensively in Wyoming, Colorado, and Utah.

Selected References

None.

Key

1 Leaflets and lobes linear to narrowly lanceolate, 0.5–6(–10) mm wide. Clematis hirsutissima var. hirsutissima
1 Leaflets and lobes narrowly to broadly lanceolate or ovate, 5–15 mm wide. Clematis hirsutissima var. scottii