Helenium flexuosum |
Helenium virginicum |
|
---|---|---|
hélénie nudiflore, purple sneezeweed, purple-head sneezeweed |
Virginia sneezeweed |
|
Habit | Perennials, 30–100 cm. | Perennials, 30–130 cm. |
Stems | usually 1, usually branched distally, strongly winged, glabrous or sparsely hairy proximally, sparsely to moderately hairy distally. |
1(–2), branched distally, strongly winged, glabrous or sparsely to moderately hairy proximally, glabrous or sparsely hairy distally. |
Leaves | glabrous or sparsely to moderately hairy; basal blades oblanceolate to obovate or spatulate, entire or serrate; proximal and mid blades oblanceolate to lanceolate, entire or toothed; distal blades lanceolate to lance-linear, entire. |
glabrous or sparsely to densely hairy; basal blades oblanceolate, weakly to strongly lobed; proximal and mid blades oblanceolate to lanceolate, usually entire, sometimes dentate; distal blades usually lanceolate, entire. |
Peduncles | 3–10 cm, sparsely to moderately hairy. |
2–8 cm, sparsely to moderately hairy. |
Involucres | globoid to usually ovoid, 8–17 × 9–17 mm. |
globoid, 8–15 × 10–16 mm. |
Ray florets | usually 8–13, neuter, sometimes 0; corollas yellow to reddish brown to red to purple, 10–20 × 5–10 mm. |
8–13, pistillate, fertile; corollas yellow, 10–15 × 4–10 mm. |
Disc florets | 250–500(–700+); corollas yellow proximally and purple distally or purple throughout, 2.3–3.7 mm, lobes 4(–5). |
200–400+; corollas yellow proximally, yellow to yellow-brown distally, 2.5–3.5 mm, lobes 5. |
Phyllaries | (connate proximally) moderately to densely hairy. |
(connate proximally) sparsely to moderately hairy. |
Heads | (1–)5–50(–80+) per plant, in paniculiform arrays. |
2–25+ per plant, in paniculiform arrays. |
Cypselae | 1–1.2 mm, moderately hairy; pappi of 5–6 entire, aristate scales 0.6–1(–1.7) mm. |
1.8–2.3 mm, moderately hairy; pappi of 5–6 entire, aristate scales 1.3–2 mm. |
2n | = 28. |
|
Helenium flexuosum |
Helenium virginicum |
|
Phenology | Flowering (Apr–)May–Jul(–Oct). | Flowering Jul–Sep. |
Habitat | Ditches, fields, washes, along streams | Around ponds, lakes, and bogs, swampy meadows |
Elevation | 10–900 m (0–3000 ft) | 300–500 m (1000–1600 ft) |
Distribution |
AL; AR; FL; GA; IL; IN; KY; LA; MA; MD; MI; MO; MS; NC; NJ; OH; OK; PA; SC; TN; TX; VA; WI; WV; NS; ON; QC
|
MO; VA |
Discussion | It has been suggested that Helenium flexuosum may be of hybrid origin from H. campestre (perennial, 2n = 28) and some member of Helenium sect. Tetrodus (H. F. L. Rock 1957). The only member of sect. Tetrodus that has a chromosome number of 2n = 28 is H. linifolium, an annual from southern Texas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. M. C. Simurda and J. S. Knox (2000) presented ITS sequence data that placed a population of Helenium virginicum from the Ozark highlands of southern Missouri in a monophyletic group with six populations of H. virginicum from the Shenandoah Valley of Virginia. R. L. Rimer and J. W. Summers (Missouri Department of Conservation, pers. comm.) located 42 H. virginicum populations in six counties in the Ozark highlands of Missouri. G. A. Yatskievych (Missouri Botanical Garden, pers. comm. to editors) has stated, “. . . the existence of this taxon in Missouri is no longer a matter of a single odd population, but probably rather another case of a taxon with two disjunct centers following dissection of a range during the Pleistocene glaciation.” Helenium virginicum is in the Center for Plant Conservation’s National Collection of Endangered Plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 429. | FNA vol. 21, p. 431. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Gaillardiinae > Helenium | Asteraceae > tribe Heliantheae > subtribe Gaillardiinae > Helenium |
Sibling taxa | ||
Synonyms | H. nudiflorum | |
Name authority | Rafinesque: New Fl. 4: 81. (1838) | S. F. Blake: Claytonia 3: 13. (1936) |
Web links |