Vernonia acaulis |
Vernonia lettermannii |
|
---|---|---|
stemless ironweed |
narrowleaf ironweed, slimleaf ironweed |
|
Habit | Plants 4–6(–10) dm. | Plants (2–)5–6+ dm. |
Stems | ± puberulent, glabrescent. |
glabrous or glabrate. |
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 filiform, 5–9+ cm × 1–3+ mm, l/w = 25–50+, abaxially glabrate (pitted, awl-shaped hairs in pits), adaxially puberulent, glabrescent (sometimes pitted). |
Peduncles | 5–50 mm. |
6–20+ mm. |
Involucres | campanulate to hemispheric, 5–10 × 6–7 mm. |
narrowly campanulate, 7–9(–10+) × 4–5+ mm. |
Florets | 30–40(–55+). |
10–12+. |
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. |
30–40+ in 5–6+ series, sparsely tomentose, glabrescent, margins arachno-ciliolate, the outer lanceolate to subulate, 1–3 mm, inner oblong to lanceolate, 5–7+ mm, tips acute. |
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. |
3–4 mm; pappi fuscous to purplish, outer scales 25+, 0.1–0.5 mm, contrasting with 35+, 6–7+ mm inner bristles. |
2n | = 34. |
= 34. |
Vernonia acaulis |
Vernonia lettermannii |
|
Phenology | Flowering Jul–Aug. | Flowering Jul–Aug. |
Habitat | Open woods, pine savannas, bogs, disturbed places | Flood plains, terraces |
Elevation | 10–300 m (0–1000 ft) | 100–200 m (300–700 ft) |
Distribution |
FL; GA; NC; SC
|
AR; OK
|
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 | |
Name authority | (Walter) Gleason: Bull. New York Bot. Gard. 4: 222. (1906) | Engelmann ex A. Gray: Notes Compositae, 78. (1880) |
Web links |