Nabalus roanensis

Plants 18-150 cm; taproots slender or short and thickened, tuberous. Stems erect, green or purple, simple, glabrous proxi-mally, crisply tomentulose distally. Leaves: proximal present at flowering; petiolate (petioles not winged or distal narrowly winged); blades ovate, 3-22 × 2-15 cm, cori-aceous, bases cordate to truncate or rounded, margins often deeply 3-5-palmately lobed or compound, lobes and sinuses angular, ultimate margins irregularly dentate, apices acute, faces usually finely tomentulose on veins; mid cauline short-petiolate or sessile; distal short-petiolate or sessile, reduced, lanceolate. Heads in narrowly paniculiform or thyrsiform arrays (nodding). Involucres cylindric to narrowly campanulate, 12-14 × 2.5-3 mm. Calyculi of 4-6, blackish green, triangular to lanceolate bractlets 1-3 mm, densely setose. Phyllaries 5-9, green or dark green, apices blackish, linear to oblanceolate, 9-11 mm, sparsely and coarsely setose. Florets 5-7(-13); corollas greenish yellow, 8-10 mm. Cypselae tan to yellow, fusiform, subterete or angled, 4-5 mm, indistinctly 8-12-ribbed; pappi yellow to whitish, 5-6 mm. 2n = 16.

Flowering Aug-Sep. Spruce-hardwood forests, wooded slopes, open grassy summits; of conservation concern. 1600-1700 m; N.C., Tenn., Va.

Prenanthes roanensis is recognized by its 5-7 florets and dark setae on the phyllaries. It is found at mid to high elevations in the Blue Ridge Province of the Appalachian Mountains. It is rather variable and often confused with other species. It is considered rare or threatened throughout its range.

Stem 1.5-6(-10) dm, glabrous below the infl, or sometimes conspicuously long-hairy; lvs mostly glabrous or nearly so, seldom evidently hairy, the lower and middle ones petiolate, with deltoid to mostly sagittate or hastate, toothed and sometimes deeply lobed or cleft blade commonly 3-10 נ2-8 cm; infl elongate and narrow, thyrsoid- racemiform, leafy-bracteate at least below, the branches all very short; heads nodding; invol 10-12 mm, coarsely hirsute-setose, with 5-6(-9) principal bracts, these pale green with a darker median line and tip; fls 5-8(-13), ochroleucous; pappus stramineous; 2n=16. Rich woods and moist, open slopes at high elev. in the s. Appalachian Mts., mainly or wholly in the Blue Ridge province; N.C. and Tenn. to sw. Va. and reputedly Ky. Aug., Sept. (P. cylindrica) Intergrades with no. 11 [Prenanthes altissima L.]

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.