Stems erect, 2-5 dm, finely and densely hirtellous. Leaves simple. Leaf blade elliptic-lanceolate to narrowly ovate, unlobed, (2-)4-8 × 1.5-3.5(-4.5) cm, thin, not conspicuously reticulate; surfaces abaxially sparsely (rarely more densely) villous on veins, not glaucous. Inflorescences terminal, flowers solitary; bracts absent. Flowers urn-shaped; sepals pale purple, often suffused with green abaxially, lanceolate, 1.4-2.5 cm, margins not expanded, thin, not crispate, puberulent, tips obtuse to acute, spreading to recurved, abaxially nearly glabrous to minutely puberulent. Achenes: bodies short-pilose; beak coppery brown, 2-3.5(-4) cm, plumose. 2 n = 16.
Flowering spring-early summer. Shale barrens; of conservation concern; 400-500 m; Va.
Clematis viticaulis is known only from shale barrens developed from the Upper Devonian Brallier Formation in Bath and Rockbridge counties of western Virginia.
The coppery brown hairs on the mature beaks are useful for distinguishing this species (C. S. Keener 1967).
Much like C. ochroleuca; stem less hairy; branches usually overtopping the central axis; lvs dark green, glabrous or nearly so beneath, smaller, mostly 4-7.5 נ2-4.5 cm; mature peduncles 1-5 cm, shorter than the subtending lvs; sep only sparsely hairy outside; mature styles 2-3(-3.5) cm; 2n=16. Shale barrens in Bath and Rockbridge cos., Va. Apr.-June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.