Bidens laevis
Bidens pilosa
bur-marigold, smooth beggar-ticks, smooth beggartick
bident poilu, cobbler's pegs, common beggar-ticks, hairy beggar-ticks, Spanish needle
(sometimes in 3s or 4s) sessile;
blades obovate or elliptic to lanceolate or linear, (20–)50–100(–160+) × (5–)10–25(–40+) mm, bases cuneate to rounded, margins usually coarsely dentate to serrate, sometimes ciliate, apices acute to acuminate, faces glabrous.
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.
(10–)20–60 mm.
10–20(–90) mm.
turbinate to hemispheric or broader, (4–)6–8(–10+) × 8–12+ mm.
turbinate to campanulate, 5–6 × (6–)7–8 mm.
usually 7–8, rarely 0;
laminae orange-yellow, (10–)15–25(–30) mm.
0 or (3–)5–8+;
laminae whitish to pinkish [yellowish], 2–3 or 7–15+ mm.
(25–)60–100(–150+);
corollas yellow to orange-yellow, 3–6.5 mm.
20–40(–80+);
corollas yellowish, (2–)3–5 mm.
8–12, ovate or obovate to lance-oblong, (4–)6–8(–10+) mm (tips often orange to purplish, as are tips of paleae).
(7–)8–9(–13), lanceolate to oblanceolate, 4–6 mm.
of 5–7(–9+) erect or spreading to reflexed, oblanceolate or lanceolate to linear, often foliaceous bractlets or bracts (6–)10–12(–20+) mm, margins usually ciliate, abaxial faces glabrous or bases hispidulous.
(6–)7–9(–13) ± appressed, spatulate to linear bractlets (3–)4–5 mm, margins ciliate, abaxial faces usually hispidulous to puberulent.
(erect at flowering, sometimes nodding in fruit) borne singly or in open, ± corymbiform arrays.
usually borne singly, sometimes in open, ± corymbiform arrays.
blackish, red-brown, or stramineous, obcompressed, flattened or unequally 3–4-angled, ± cuneate, outer 6–8 mm, inner 8–10 mm, margins retrorsely ciliate or barbed, apices ± truncate to convex, faces ± 1-nerved, ± striate, glabrous;
pappi of 2–4 ± erect, retrorsely barbed awns 3–5 mm.
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.
= 22, 24.
= 24, 36, 48, 72.
Bidens laevis
Bidens pilosa
Bidens laevis and B. cernua are similar in gross appearance; specimens of one are sometimes misidentified as the other. Perhaps they represent extremes of a single species.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.)
CA
Go Botany
LA Plants
MD Biodiversity
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
BC
PNW Herbaria
