Bidens pilosa |
Bidens heterodoxa |
|
---|---|---|
bident poilu, cobbler's pegs, common beggar-ticks, hairy beggar-ticks, Spanish needle |
bident différent, connecticut beggarticks |
|
Habit | Annuals [perennials], (10–)30–60(–180+)[–250] cm. | Annuals, (5–)25–35(–55+) cm. |
Leaves | petioles 10–30(–70) mm; blades either ovate to lanceolate, 30–70(–120) × 12–18(–45) mm, or 1-pinnately lobed, primary lobes 3–7, ovate to lanceolate [linear], (10–)25–80+ × (5–)10–40+ mm [blades 2(–3)-pinnatisect], bases truncate to cuneate, ultimate margins serrate or entire, usually ciliate, apices acute to attenuate, faces pilosulous to sparsely hirtellous or glabrate. |
petioles (narrowly, if at all, winged) 5–20(–35+) mm; blades lanceolate to lance-linear, (20–)30–50(–80+) × (3–)6–20(–30+) mm, sometimes laciniately 1-pinnatisect with 2–4+ lobes near bases, bases cuneate, margins incised to serrate, seldom ciliate, apices acute to attenuate, faces glabrous. |
Peduncles | 10–20(–90) mm. |
10–35(–55) mm. |
Involucres | turbinate to campanulate, 5–6 × (6–)7–8 mm. |
usually obconic to broadly campanulate, rarely hemispheric, (4–)6–7 × (4–)5–7 mm. |
Ray florets | 0 or (3–)5–8+; laminae whitish to pinkish [yellowish], 2–3 or 7–15+ mm. |
usually 0, sometimes 1–3+; laminae orange yellowish, 2–5(–10) mm. |
Disc florets | 20–40(–80+); corollas yellowish, (2–)3–5 mm. |
(7–)20–70+; corollas yellowish, 2.5–3.5 mm. |
Phyllaries | (7–)8–9(–13), lanceolate to oblanceolate, 4–6 mm. |
(4–)5–8,oblong to lance-ovate, (4–)5–8+ mm. |
Calyculi | (6–)7–9(–13) ± appressed, spatulate to linear bractlets (3–)4–5 mm, margins ciliate, abaxial faces usually hispidulous to puberulent. |
of (2–)3–5(–7) ± erect, oblanceolate or spatulate to linear, ± foliaceous bractlets or bracts (6–)10–25(–40+) mm, margins rarely ciliate, abaxial faces usually glabrous, sometimes sparsely hispidulous. |
Heads | usually borne singly, sometimes in open, ± corymbiform arrays. |
borne singly or in 2s or 3s. |
Cypselae | outer red-brown, ± flat, linear to narrowly cuneate, (3–)4–5+ mm, margins antrorsely hispidulous, apices ± truncate or somewhat attenuate, faces obscurely 2-grooved, sometimes tuberculate-hispidulous; inner blackish, ± equally 4-angled, linear-fusiform, 7–16 mm, margins antrorsely hispidulous, apices ± attenuate, faces 2-grooved, tuberculate-hispidulous to sparsely strigillose; pappi 0, or of 2–3(–5), erect to divergent, retrorsely barbed awns (0.5–)2–4 mm. |
outer red-brown, ± flattened, sometimes 3–4-angled, broadly cuneate, 4–5(–6) mm, inner blackish, narrowly cuneate, (5–)6–7(–8+) mm, margins glabrous or sparsely antrorsely strigillose,apices ± truncate to convex, faces ± 1-nerved, glabrous or sparsely setulose, usually smooth, sometimes ± tuberculate; pappi 0, or of 2(–4) spreading to divergent, antrorsely or retrorsely barbed awns (0.1–)1–3.5+ mm. |
2n | = 24, 36, 48, 72. |
= 48. |
Bidens pilosa |
Bidens heterodoxa |
|
Phenology | Flowering year round. | Flowering Aug–Oct. |
Habitat | Disturbed, wettish sites | Borders of estuaries, lakes, marshes, streams |
Elevation | 10–1900 m (0–6200 ft) | 0–10 m (0–0 ft) |
Distribution |
AL; AZ; CA; CT; FL; GA; KY; LA; MA; MD; MO; MS; NC; NM; PA; SC; TX; ON; QC; Mexico; Central America [Introduced, Europe]
|
CT; NB; PE; QC |
Discussion | R. Ballard (1986) adopted a narrower circumscription of Bidens pilosa than that used here. He used: B. pilosa for plants with outer phyllaries 7–10, ray florets usually 0 (when present, laminae 2–3 mm), disc florets 35–75, pappi of 3(–5) awns 1–3 mm, and 2n = 72; B. alba for plants with outer phyllaries (8–)12(–16), ray florets 5–8 (laminae 5–16 mm), pappi of 2 awns 1–2 mm, and 2n = 48; and B. odorata for plants with outer phyllaries (6–)8(–12), ray florets 5–8 (laminae 3–18 mm), disc florets 12–61, pappi 0, or of 1–2 awns 1–3 mm, and 2n = 24. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Bidens heterodoxa may be better treated as part of B. tripartita. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 211. | FNA vol. 21, p. 218. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Bidens | Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Bidens |
Sibling taxa | ||
Synonyms | B. alba, B. alba var. radiata, B. odorata, B. pilosa var. radiata | B. tripartita var. heterodoxa, B. heterodoxa var. agnostica, B. heterodoxa var. monardifolia, B. heterodoxa var. orthodoxa, B. infirma |
Name authority | Linnaeus: Sp. Pl. 2: 832. (1753) | (Fernald) Fernald & H. St. John: Rhodora 17: 23. (1915) |
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