Southeastern Sneezeweed

Perennials, 30–80 cm. Stems usually 1, usually unbranched distally, weakly winged, glabrous or sparsely to moderately hairy proximally, sparsely to moderately hairy distally. Leaves usually glabrous, rarely sparsely hairy; basal blades obovate to oblanceolate, usually pinnatifid, sometimes undulate to undulate-serrate, rarely entire; proximal and mid blades linear-oblanceolate to lance-linear, entire or undulate-serrate; distal blades lance-linear, entire. Heads 1(–3) per plant, usually borne singly. Peduncles 3–20 cm, moderately to densely hairy. Involucres hemispheric, 12–20 × 15–30 mm. Phyllaries moderately hairy. Ray florets 13–34, neuter; corollas yellow, 15–22 × 5–8 mm. Disc florets 250–650(–800+); corollas yellow proximally, yellow to yellow-brown distally, 4–5.5 mm, lobes 5. Cypselae 1.2–1.4 mm, moderately hairy; pappi of 8–11 entire or slightly lacerate, non-aristate scales 1.2–1.5 mm. 2n = 32, 34.

Leptopoda pinnatifida Schweinitz ex Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 372. 1841

Helenium incisum (T. & G.) Wood, Bot. & Fl. 182. 1870
Leptopoda incisa T. & G. Fl. N. Am. 2: 387. 1842.
Helenium Nuttallii incisum A. Gray, Proc. Am. Acad. 9: 204. 1874.
A simple slender perennial, with a short rootstock ; stem 3-7 dm. high, glabrous or sparingly puberulent, only slightly winged; basal leaves linear-oblanceolate or linear, rather thick, 5-10 cm. long, pinnately lobed or coarsely toothed, the lobes or teeth alternate; upper stemleaves linear or linear-subulate, merely dentate; peduncles 5-15 cm. long, thickened below the head; bracts linear-subulate, 5-8 mm. long, spreading, in age recurved; ray-flowers neutral; ligules yellow, 1-1.5 cm. long, 5-7 mm. wide, deeply lobed; disk yellow, 15-20 mm. broad; corollas 4 mm. long; tube minute; achenes 1.5 mm. long, glabrous or sparingly glandulargranuliferous; squamellae oval, fimbriate.
Type locality: Georgia. Distribution: Georgia to Mississippi.

Helenium pinnatifidum (Schw.) Rydberg
Leptopoda puberula MacBride; Ell. Bot. S. C. & Ga. 2: 445. 1824.
? Leptopoda floridana Raf. Atl. Jour. 147. 1832.
Leptopoda pinnatifida Schw.; Nutt. Trans. Am. Phil. Soc. II. 7: 372. 1841.
Leptopoda puberula pinnatifida T. & G. Fl. N. Am. 2: 387. 1842.
Helenium puberulum Wood, Bot. & Fl. 182. 1870. Not H. puberulum DC. 1836.
Helenium vernale A. Gray, Syn. Fl. N. Am. I 2 : 350, mainly. 1884. Not H. vernale Watt. 1788.
A simple perennial, with a rootstock; stem 3-7 dm. high, more or less puberulent or shortvillous; basal leaves linear-oblanceolate, usually coarsely toothed or pinnatifid, somewhat puberulent, somewhat fleshy, 5-20 cm. long; stem-leaves small, linear or lance-linear, dentate to entire; heads solitary, 5-15 cm. long, enlarged under the involucre; bracts 5-7 mm. long, spreading, at last recurved; ray-flowers neutral; ligules yellow, 6-10 mm. long, deeply cleft; disk yellow, 1-2 cm. broad; corollas 4.5 mm. long; tube very short; achenes 1.5-2 mm. long, hirsute on the angles; squamellae oblong, 1.5 mm. long, erose.
Type locality: East Florida.
Distribution: North Carolina to Florida and Alabama.

Helenium pinnatifidum is a North American perennial plant in the sunflower family, commonly known as southeastern sneezeweed. It is found in the southeaster United States (Alabama, Georgia, Florida, and the Carolinas).

Helenium pinnatifidum is an perennial herb up to 80 cm (31.5 in) tall, with small wings running down the sides of the stems. Leaves are pinnatifid, meaning deeply divided into many small parts. One plant generally produces only 1-3 hemispherical flower heads, about 2 cm (1 in) across. Each head can have 800 or more minuscule disc flowers 4.0–5.5 mm (0.16–0.22 in) across, each yellow toward the bottom but yellow-brown toward the tip. There are also 13-34 yellow ray flowers, each with three prominent lobes at the tip.