Vernonia acaulis |
Vernonia marginata |
|
---|---|---|
stemless ironweed |
ironplant, plains ironweed |
|
Habit | Plants 4–6(–10) dm. | Plants 3–5(–8+) dm. |
Stems | ± puberulent, glabrescent. |
puberulent, glabrescent. |
Leaves | mostly basal; blades oblong-elliptic to spatulate (basal, the distal narrower), 11–25(–30) cm × (21–)60–75+ mm, l/w = 2–4(–5+), abaxially usually glabrous or glabrate, sometimes hirsutulous on veins, usually resin-gland-dotted, adaxially ± scabrellous or glabrate. |
mostly cauline; blades narrowly lanceolate to lance-linear, 5–15+ cm × (2.5–)8–12+ mm, l/w = 8–20(–30+), abaxially glabrate (pitted, awl-shaped hairs in pits), adaxially puberulent, glabrescent (sometimes pitted). |
Peduncles | 5–50 mm. |
(3–)10–35 mm. |
Involucres | campanulate to hemispheric, 5–10 × 6–7 mm. |
narrowly campanulate, (7–)9–11 × 5–6 mm. |
Florets | 30–40(–55+). |
10–25+. |
Phyllaries | 40–60 in 5–6 series, glabrate, margins ciliolate, the outer lance-linear, 2–4 mm, inner lance-ovate to lance-subulate, 5–9 mm, tips subulate to filiform. |
35–40+ in 5–6+ series, glabrescent, margins arachno-ciliolate, the outer lance-ovate, 1–2 mm, inner oblong to linear-oblong, 6–9+ mm, tips ± acuminate. |
Heads | in loose, corymbiform arrays. |
in corymbiform arrays. |
Cypselae | 2.5–3+ mm; pappi whitish to stramineous, outer scales ca. 20, 0.6–1 mm, contrasting with 25–40, 5–7+ mm inner bristles. |
4–5 mm; pappi stramineous to purplish, outer subulate scales or bristles 30+, 0.6–2+ mm, intergrading with 40+, 8–9+ mm inner subulate scales or bristles. |
2n | = 34. |
= 34. |
Vernonia acaulis |
Vernonia marginata |
|
Phenology | Flowering Jul–Aug. | Flowering Jul–Aug. |
Habitat | Open woods, pine savannas, bogs, disturbed places | Ditches, sandy flats, stream banks |
Elevation | 10–300 m (0–1000 ft) | 600–2000 m (2000–6600 ft) |
Distribution |
FL; GA; NC; SC
|
CO; KS; NM; OK; TX; Mexico (Coahuila)
|
Source | FNA vol. 19, p. 208. | FNA vol. 19, p. 211. |
Parent taxa | Asteraceae > tribe Vernonieae > Vernonia | Asteraceae > tribe Vernonieae > Vernonia |
Sibling taxa | ||
Synonyms | Chrysocoma acaulis | V. altissima var. marginata |
Name authority | (Walter) Gleason: Bull. New York Bot. Gard. 4: 222. (1906) | (Torrey) Rafinesque: Atlantic J. 1: 146. (1832) |
Web links |