Helianthus heterophyllus

Nuttall

J. Acad. Nat. Sci. Philadelphia 7: 74. 1834.

Common names: Wetland sunflower
Synonyms: Helianthus elongatus Small
Treatment appears in FNA Volume 21. Treatment on page 155. Mentioned on page 144.
Revision as of 20:37, 16 December 2019 by FNA>Volume Importer

Perennials, 50–120 cm (with crown buds). Stems erect, usually hispid to ± hirsute. Leaves mostly basal; mostly opposite; petioles 0–3 cm (broadly winged); blades (3-nerved distal to bases) ovate or lanceolate to spatulate, 6–28 × 1.2–4.3 cm, bases cuneate, margins entire (often revolute), abaxial faces hispid to ± hirsute, not gland-dotted (cauline leaves relatively few, narrowly lanceolate to linear, much smaller). Heads 1–3(–5). Peduncles 10–15 cm. Involucres broadly hemispheric, 15–25 mm diam. Phyllaries 24–30, lanceolate to lance-ovate, 8–13 × 2–5 mm, (margins sometimes ciliate) apices acute to short-acuminate or acuminate, abaxial faces sparsely hispid to glabrate. Paleae 7–9 mm, 3-toothed (apices purplish). Ray florets 12–18; laminae 14–36 mm (abaxial faces not gland-dotted). Disc florets 100+; corollas 5.5–6.5 mm, lobes reddish; anthers purplish, apendages purplish (style branches usually reddish). Cypselae 4–5 mm, glabrate; pappi of 2 aristate scales 1.7–2.5 mm plus 1–3 deltate scales 0.5–1.5 mm. 2n = 34.


Phenology: Flowering late summer–fall.
Habitat: Wet sandy soils
Elevation: 0–50+ m

Distribution

V21-368-distribution-map.gif

Ala., Fla., Ga., La., Miss., N.C., S.C., Tex.

Discussion

Helianthus heterophyllus is found on the Atlantic and Gulf coastal plains. The cauline leaves are usually abruptly reduced relative to the basal leaves; individuals sometimes have relatively large cauline leaves.

Selected References

None.

Lower Taxa

None.