Cyanthillium cinereum |
Cyanthillium |
|
---|---|---|
little ironweed |
ironweed |
|
Habit | Annuals (perhaps persisting), 2–6(–12+) dm. | |
Leaves | blades 20–35(–50+) × 12–25(–30+) mm (including petioles). |
mostly cauline (at flowering); petioles ± winged; blades ovate to trullate, deltate, oblanceolate, or spatulate, bases ± cuneate, margins serrate, apices rounded to acute, abaxial faces ± hirtellous to densely piloso-strigillose, resin-gland-dotted, adaxial faces ± scabrellous or glabrate. |
Bracts | ± linear at proximal nodes, wanting distally. |
|
Peduncles | 3–10(–20+) mm. |
|
Involucres | ± campanulate to turbinate or hemispheric, 4–5 mm diam. |
|
Florets | 13–20(–24+); corollas lavender to pink or purplish, tubes longer than funnelform throats, lobes 5, lance-linear, ± equal. |
|
Phyllaries | 3–4 mm. |
24–32+ in 3–4+ series, the outer subulate to lanceolate, inner ± lanceolate, all ± chartaceous, margins entire, tips apiculate to spinose, abaxial faces ± strigillose, ± resin-gland-dotted. |
Heads | discoid, ± pedunculate, not subtended by foliaceous bracts, (12–)40–100+ in ± corymbiform arrays (6–)10–15+ cm diam. |
|
Cypselae | 1.5–2 mm; pappi white, outer scales 0.1–0.3 mm, inner bristles 3–4 mm. |
± columnar, not ribbed, ± strigillose; pappi of ± 20 ± persistent outer scales, plus ± 20 caducous inner bristles. |
x | = 9 (18?). |
|
2n | = 36. |
|
Cyanthillium cinereum |
Cyanthillium |
|
Phenology | Flowering year-round. | |
Habitat | Disturbed places | |
Elevation | 0–10 m (0–0 ft) | |
Distribution |
FL; Mexico; Central America; South America; West Indies; Asia; Africa; Indian Ocean Islands; Pacific Islands [Introduced in North America] |
FL; probably paleotropical in origin; now widely established in tropical and warm-temperate regions as naturalized ruderals [Introduced in North America] |
Discussion | Species 1–2 (1 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 19, p. 205. | FNA vol. 19, p. 204. |
Parent taxa | Asteraceae > tribe Vernonieae > Cyanthillium | Asteraceae > tribe Vernonieae |
Subordinate taxa | ||
Synonyms | Conyza cinerea, Vernonia cinerea | |
Name authority | (Linnaeus) H. Robinson: Proc. Biol. Soc. Wash. 103: 252. (1990) | Blume: Bijdr. Fl. Ned. Ind., 889. (1826) |
Web links |