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stemless ironweed

Texas ironweed

Habit Plants 4–6(–10) dm. Plants 4–8(–10+) 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.

basal and cauline;

blades ovate-lanceolate (basal) to narrowly lanceolate (distal), 5–12+ cm × (5–)12–25+ mm, l/w = 3–5 (basal) or 8–17 (distal), abaxially glabrate (pitted, awl-shaped hairs in pits), adaxially puberulent and/or scabrellous.

Peduncles

5–50 mm.

1–35 mm.

Involucres

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

± obconic to hemispheric, 4.5–6 × 5–7 mm.

Florets

30–40(–55+).

12–24+.

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.

35–45+ in 5–6+ series, glabrescent, margins arachno-ciliolate, the outer lance-deltate, 1–32 mm, inner oblong to linear, 4–5(–6) mm, tips acute or rounded-apiculate.

Heads

in loose, corymbiform arrays.

in open, paniculiform-scorpioid 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.

2–3 mm;

pappi usually whitish to stramineous (rarely purplish), outer scales or bristles 20+, 0.3–1+ mm, contrasting or intergrading with 20+, 6–7+ mm inner subulate scales or bristles.

2n

= 34.

= 34.

Vernonia acaulis

Vernonia texana

Phenology Flowering Jul–Aug. Flowering Jun–Aug.
Habitat Open woods, pine savannas, bogs, disturbed places Pinelands, scrub oak woodlands, sandy or sandy-clay soils
Elevation 10–300 m (0–1000 ft) 60–200 m (200–700 ft)
Distribution
from FNA
FL; GA; NC; SC
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; LA; MS; OK; TX
[WildflowerSearch map]
[BONAP county map]
Source FNA vol. 19, p. 208. FNA vol. 19, p. 211.
Parent taxa Asteraceae > tribe Vernonieae > Vernonia Asteraceae > tribe Vernonieae > Vernonia
Sibling taxa
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
V. acaulis, 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
Synonyms Chrysocoma acaulis V. angustifolia var. texana
Name authority (Walter) Gleason: Bull. New York Bot. Gard. 4: 222. (1906) (A. Gray) Small: Fl. S.E. U.S., 1338. (1903)
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