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tall ironweed

stemless ironweed

Habit Plants 5–10+ dm. Plants 4–6(–10) dm.
Stems

sparsely appressed-puberulent, glabrescent.

± puberulent, glabrescent.

Leaves

mostly cauline;

blades (mid stem) lance-linear to filiform, 5–12 cm × 2–4(–8+) mm, l/w = (8–)12–30(–60+), abaxially glabrous but for scattered hairs on midribs or scabrellous (hairs awl-shaped), resin-gland-dotted or not, adaxially scabrellous.

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.

Peduncles

8–25 mm.

5–50 mm.

Involucres

± campanulate to obconic, 5–7(–10) × 4–6(–9) mm.

campanulate to hemispheric, 5–10 × 6–7 mm.

Florets

12–20(–30).

30–40(–55+).

Phyllaries

22–45+ in 5–6 series, sparsely scabrellous, glabrescent, margins ciliolate, the outer lanceolate to subulate, 1.5–3 mm, inner lance-ovate to lanceolate, 5–9+ mm, tips acuminate to subulate.

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.

Heads

in ± corymbiform to paniculiform arrays.

in loose, corymbiform arrays.

Cypselae

2.5–3 mm;

pappi stramineous to purplish, outer scales 25–30, 0.5–1.2+ mm, contrasting with 35–40+, 5.5–6+ mm inner bristles.

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.

2n

= 34.

= 34.

Vernonia angustifolia

Vernonia acaulis

Phenology Flowering Jun–Aug. Flowering Jul–Aug.
Habitat Pine barrens, oak woodlands Open woods, pine savannas, bogs, disturbed places
Elevation 10–50 m (0–200 ft) 10–300 m (0–1000 ft)
Distribution
from FNA
AL; FL; GA; LA; MS; NC; SC
[WildflowerSearch map]
[BONAP county map]
from FNA
FL; GA; NC; SC
[WildflowerSearch map]
[BONAP county map]
Source FNA vol. 19, p. 209. FNA vol. 19, p. 208.
Parent taxa Asteraceae > tribe Vernonieae > Vernonia Asteraceae > tribe Vernonieae > Vernonia
Sibling taxa
V. acaulis, V. arkansana, V. baldwinii, V. blodgettii, V. fasciculata, V. flaccidifolia, V. gigantea, V. glauca, V. larseniae, V. lettermannii, V. lindheimeri, V. marginata, V. missurica, V. noveboracensis, V. pulchella, V. texana
V. angustifolia, V. arkansana, V. baldwinii, V. blodgettii, V. fasciculata, V. flaccidifolia, V. gigantea, V. glauca, V. larseniae, V. lettermannii, V. lindheimeri, V. marginata, V. missurica, V. noveboracensis, V. pulchella, V. texana
Synonyms V. angustifolia subsp. mohrii, V. angustifolia subsp. scaberrima, V. angustifolia var. scaberrima, V. scaberrima Chrysocoma acaulis
Name authority Michaux: Fl. Bor.-Amer. 2: 94. (1803) (Walter) Gleason: Bull. New York Bot. Gard. 4: 222. (1906)
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