Helenium quadridentatum

Labillardière

Actes Soc. Hist. Nat. Paris 1: 22, plate 4. 1792.

Common names: Longdisk sneezeweed
Treatment appears in FNA Volume 21. Treatment on page 434. Mentioned on page 428.
Revision as of 15:29, 18 September 2019 by FNA>Volume Importer

Annuals, 30–100 cm. Stems usually 1, branched distally, moderately to strongly winged, glabrous or sparsely hairy. Leaves glabrous or sparsely hairy; blades narrowly elliptic to lance-linear, usually entire; proximal blades sometimes pinnately lobed. Heads 5–15(–50+) per plant, in paniculiform arrays. Peduncles 3–13 cm, sparsely to moderately hairy. Involucres ovoid to conic, 7–11(–14) × 6–11 mm. Phyllaries (connate proximally) sparsely to densely hairy. Ray florets 10–15, pistillate, fertile; corollas yellow, 7–12.4 × 4–8.8 mm. Disc florets 225–500+; corollas yellow proximally, yellow to brown to reddish brown distally, 1.1–1.8 mm, lobes 4. Cypselae 0.6–1.2 mm, moderately hairy; pappi of usually 6 entire, non-aristate scales 0.1–0.3 mm. 2n = 26.


Phenology: Flowering Mar–Jun (year round).
Habitat: Sandy or clay soils, ditches, around ponds and lakes, along streams
Elevation: 0–1800 m

Distribution

V21-1089-distribution-map.gif

Ala., La., Miss., Pa., Tex., Mexico, West Indies (Cuba), Central America (Belize, Guatemala).

Discussion

Helenium quadridentatum is introduced in Pennsylvania.

Selected References

None.

Lower Taxa

None.
... more about "Helenium quadridentatum"
Mark W. Bierner +
Labillardière +
Longdisk sneezeweed +
Ala. +, La. +, Miss. +, Pa. +, Tex. +, Mexico +, West Indies (Cuba) +, Central America (Belize +  and Guatemala). +
0–1800 m +
Sandy or clay soils, ditches, around ponds and lakes, along streams +
Flowering Mar–Jun (year round). +
Actes Soc. Hist. Nat. Paris +
Compositae +
Helenium quadridentatum +
Helenium +
species +