Perennials, 30-200+ dm (rhi-zomatous). Stems erect, glabrous (distinctively bluish, glacous). Leaves cauline; all or mostly opposite; sessile; blades (1-nerved) lanceolate to lance-ovate, 7-16.5 × 1.5-3.5 cm, bases cuneate, margins entire or serrulate, faces glabrous (abaxial) or strumose (adaxial), gland-dotted. Heads 1-5. Peduncles 1-4 cm. Involucres hemispheric, 10-25 mm diam. Phyllaries 30-38, lance-olate, 12-16 × 3.5-4.5 mm, (margins ciliate) apices acuminate, abaxial faces glabrate, not gland-dotted. Paleae 9-11 mm, entire or ± 3-toothed (apices deltate). Ray florets 10-18; laminae 15-20 mm. Disc florets 70+; corollas 5-7 mm, lobes yellow; anthers dark, appendages dark or ± yellowish. Cypselae 4-6 mm, glabrous; pappi of 2 aristate scales 3-4 mm plus 0-1 deltate scales 0.5-1 mm. 2n = 102. Flowering late summer-fall. Open barrens, open oak-hickory woodlands; of conservation concern: 100-300 m; Ala., Ky., Tenn. Helianthus eggertii is similar to H. strumosus and H. laevigatus; it is distinguished by the distinctive blue coloration of stems and leaves and by the leaves usually 1-nerved, in contrast to the 3-nerved condition typical for the genus. It is listed federally as an endangered species; R. L. Jones (1994) found it to be more common than was previously thought, and it is now in the process of being removed from the federal list.
Fibrous-rooted perennial from long rhizomes; stems 1-2 m, glabrous and glaucous; lvs mostly or all opposite, glabrous or nearly so above, glabrous and strongly
glaucous beneath, lanceolate, mostly 9-15 נ1.5-3.5 cm, entire or serrulate, tapering to a sessile or subsessile base; heads rather few, on long peduncles often 1-1.5 dm; disk yellow, 1.2-2 cm wide; invol bracts firm, lance-acuminate, ciliolate, about equaling the disk; rays 10-14, to 2 cm; 2n=102. Rocky hills and barrens; ec. Ky. to c. Tenn. Aug., Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.