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Baldwin's ironweed

Arkansas ironweed, great ironweed

Habit Plants 6–10(–15) dm. Plants 8–12(–20) dm.
Stems

puberulent to ± tomentose.

scabrellous to pilosulous, glabrescent.

Leaves

mostly cauline;

blades elliptic to lance-ovate or lanceolate, 8–15(–18+) cm × 20–45(–75+) mm, l/w = 2–5, abaxially usually puberulent to tomentose or pannose (hairs ± erect, ± curled), seldom glabrate, resin-gland-dotted, adaxially scabrellous, glabrescent, not resin-gland-dotted.

mostly cauline;

blades lance-linear, 6–14(–20) cm × 7–15(–25) mm, l/w = 7–10(–18), abaxially scabrellous (hairs awl-shaped), resin-gland-dotted, adaxially scaberulous, glabrescent, resin-gland-dotted.

Peduncles

1–25 mm.

2–5 cm.

Involucres

broadly campanulate to hemispheric, 4–6(–8+) × 4–7+ mm.

± hemispheric, 11–15 × 11–15 mm.

Florets

(15–)20–25(–35+).

50–100+.

Phyllaries

45–65+ in 5–6 series, usually puberulent (often resin-gland-dotted distally), sometimes glabrescent, margins ciliolate, the outer lance-ovate, 1–2 mm, inner oblong to lanceolate, 5–8+ mm, tips rounded-apiculate to acute (sometimes recurved).

(50–)60–70+ in 5–6 series, scabrellous (and resin-gland-dotted), margins ciliolate, the outer lance-ovate, 3–8+ mm, inner lanceolate, 12–15 mm, tips subulate to filiform.

Heads

in corymbiform-scorpioid arrays.

in ± corymbiform arrays.

Cypselae

2.5–3 mm;

pappi fuscous to purplish, outer scales 25–30, 0.2–1 mm, contrasting with 35–40+, 5–7+ mm inner bristles.

3–5 mm;

pappi fuscous to purplish, outer scales 25–30+, 0.5–1 mm, contrasting with 25–30+, 5–7 mm inner bristles.

2n

= 34.

= 34.

Vernonia baldwinii

Vernonia arkansana

Phenology Flowering Jun–Nov. Flowering Aug–Oct.
Habitat Disturbed places, grasslands, flood plains, forest margins, prairies Leas, roadsides, stream banks, in sand or on limestone
Elevation 10–1100 m (0–3600 ft) 200–300 m (700–1000 ft)
Distribution
from FNA
AR; CO; IA; IL; KS; KY; LA; MI; MO; NE; OK; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; KS; MO; OK
[WildflowerSearch map]
[BONAP county map]
Discussion

Regarding Vernona baldwinii and V. interior, L. H. Shinners (1950) wrote, “The tips of the phyllaries vary from loosely appressed to squarrose, and from puberulent to almost completely glabrous on the inner face. The geographic distribution of the two extremes is nearly identical. I consider the two to be merely forms of one species.” I concur.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Vernonia arkansana was published in April, V. crinita in October 1838.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 19, p. 213. FNA vol. 19, p. 208.
Parent taxa Asteraceae > tribe Vernonieae > Vernonia Asteraceae > tribe Vernonieae > Vernonia
Sibling taxa
V. acaulis, V. angustifolia, V. arkansana, 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. 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. baldwinii subsp. interior, V. baldwinii var. interior, V. interior V. crinita
Name authority Torrey: Ann. Lyceum Nat. Hist. New York 2: 211. (1827) de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 7: 264. (1838)
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