Helianthus laevigatus Torr. & A. Gray
Family: Asteraceae
Smooth Sunflower
[Helianthus reindutus (Steele) E.E. Watson]
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Perennials, 100-220 cm (rhizomatous). Stems erect, usually glabrous, sometimes proximally hirsute (glaucous). Leaves cauline; opposite (proximal) or alternate ; sessile or subsessile; blades (grayish green or bluish green) lanceolate, 8-15 × 1.5-3.5 cm, bases ± cuneate, margins serrate to subentire, abaxial faces glabrous or glabrate (smooth or slightly rough to touch, glaucous). Heads 1-6. Peduncles 2-8 cm. cm. Involucres cylindric, 10-15 mm diam. Phyllaries 23-28, lanceolate, 6-13 × 2-3 mm, (margins sometimes ciliate) apices acuminate, abaxial faces glabrous, not gland-dotted. Paleae 8.5-10 mm, 3-toothed to subentire. Ray florets 5-10; laminae 15-20 mm. Disc florets 35+; corollas 5.5-6.5 mm, lobes yellow; anthers dark, appendages dark. Cypselae 4-5.5 mm, glabrous; pappi of 2 aristate scales 3.2-4.1 mm plus 0-1 deltate scales 0.5-1.1 mm. 2n = 68.

Flowering late summer-fall. Shale barrens; 300-900+ m; N.C., S.C., Va., W.Va.

Fibrous-rooted perennial from a crown or short rhizome; stems 1-2 m, glabrous, often glaucous; lvs firm, essentially glabrous, serrulate to entire, lanceolate to sometimes lance-elliptic or lance-ovate, 6-18 נ1-4 cm, narrowed to a subsessile base or short petiole less than 1 cm; upper lvs alternate; heads rather small, the yellow disk 1-1.5 cm wide; invol bracts subequal or slightly imbricate, lanceolate, acuminate-attenuate, often ciliolate, otherwise glabrous; rays 5-10(-13), 1-2 cm; 2n=68. Mainly on shale-barrens in our range; mts. of Va. and W.Va. to N.C. and S.C. Aug.-Oct. (H. reindutus)

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

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