Tridax procumbens |
Tridax |
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cadillo chisaca, coat buttons, tridax |
tridax |
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Habit | Perennials [annuals], 10–40[–80+] cm. | |
Stems | procumbent to ascending. |
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Leaves | petioles 1–10(–30) mm; blades 10–40(–120) × 5–20(–60) mm, often 3-lobed. |
basal and/or cauline; opposite; petiolate [sessile]; blades deltate, lanceolate, lance-ovate, or ovate, often pinnately or palmately lobed, ultimate margins coarsely toothed to subentire, faces glabrate, hirsute, scabrellous, or strigillose. |
Involucres | cylindric to hemispheric, 4–8 mm diam. |
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Receptacles | convex to conic, paleate (paleae ± persistent, lance-linear, scarious, weakly conduplicate, often apically toothed). |
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Ray florets | [0–]3–8[–13], pistillate, fertile; corollas pale yellow [white or purplish]. |
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Disc florets | [20–]40–80+, bisexual, fertile; corollas yellowish [whitish or purplish], tubes shorter than cylindric or funnelform throats, lobes 5, usually deltate [sometimes rays 0 and corollas of peripheral florets ± bilabiate]. |
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Phyllaries | persistent, 11–15+ in 2–3+ series (outer usually shorter, more herbaceous, the inner often scarious). |
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Heads | radiate [discoid], borne singly [in ± cymiform arrays]. |
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Cypselae | 2–2.5 mm; pappi 4–5(–7.5) mm. |
obconic to obpyramidal, 3-, 4-, or 5-angled, densely piloso-sericeous [glabrous, villous]; pappi [sometimes wanting in rays] persistent, of [10–]20[–40], plumose [ciliate], setiform scales. |
x | = 10. |
|
2n | = 36. |
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Tridax procumbens |
Tridax |
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Phenology | Flowering Jan–Dec. | |
Habitat | Disturbed sites | |
Elevation | 0–10 m (0–0 ft) | |
Distribution |
FL; TX; Mexico [Introduced in North America]
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mostly tropical; mostly New World [Introduced in North America] |
Discussion | Tridax procumbens is listed as a noxious weed for United States and is listed as a pest or noxious weed for nine or more states. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Species ca. 26 (1 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 180. | FNA vol. 21, p. 179. |
Parent taxa | ||
Subordinate taxa | ||
Name authority | Linnaeus: Sp. Pl. 2: 900. (1753) | Linnaeus: Sp. Pl. 2: 900. (1753): Gen. Pl. ed. 5, 382. (1754) |
Web links |