Helianthus occidentalis
W. J. Med. Phys. Sci. 9: 577. 1836.
Perennials, 60–150 cm (rhizomatous, sometimes stoloniferous as well). Stems (often reddish) erect, pilose to appressed-hairy proximally. Leaves mostly basal; opposite; petioles 2.5–10 cm; blades oblong-lanceolate or elliptic to ovate, 5–20 × 1.5–7 cm, bases cuneate, margins entire or serrulate, abaxial faces scabrous to hispidulous, glanddotted (cauline usually smaller, rarely 2–4 pairs well developed). Heads 1–4 (–12). Peduncles 1–14 cm. Involucres cylindric, 9–14 mm diam. Phyllaries 20–25, lanceolate, 4.5–7 (–11) × 1.5–2.5 mm, (margins usually ciliate) apices acute to short-acuminate, abaxial faces glabrate to sparsely pilose (hairs moniliform), not glanddotted. Paleae 5–7 mm, subentire to 3-toothed (shortly mucronate). Ray-florets 8–14; laminae 18–22 mm (abaxial faces densely glanddotted). Disc-florets 50+; corollas 4.5–5.5 mm, lobes yellow; anthers dark-brown or black, appendages yellow. Cypselae 3–4 (–5) mm, sparsely villous or glabrate; pappi of 2 aristate scales 1.5–2.8 mm plus 0–4 deltate scales 0.4–1 mm. 2n = 34 (subspecies unknown).
Distribution
Ark., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., Mass., Md., Mich., Mo., N.C., N.J., Ohio, Pa., S.C., Tenn., Tex., Va., W.Va., Wis.
Discussion
Subspecies 2 (2 in the flora).
Selected References
None.
Key
1 | Leaves entire or nearly so, scabrous or hirsute, rough to touch | Helianthus occidentalis subsp. occidentalis |
1 | Leaves usually serrate, strigose or glabrous, smooth to touch | Helianthus occidentalis subsp. plantagineus |