Bidens amplissima |
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Vancouver Island beggar-ticks |
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Habit | Annuals, (30–)50–120 cm. |
Leaves | sessile or petioles 10–50 mm (winged); blades lance-elliptic to lance-oblong, 80–120(–250) × 30–100 mm (proximal usually with 1–2 lobes near bases), bases cuneate, margins laciniate to serrate, ciliate, apices acuminate, faces glabrous. |
Peduncles | (10–)30–70+ mm. |
Involucres | ± hemispheric or broader, 6–10 × 18–25 mm. |
Ray florets | 6–11; laminae yellow, 4–8 mm. |
Disc florets | 50–100+; corollas yellow, 2.5–3.5 mm. |
Phyllaries | 13–16+, oblong to lance-ovate, 6–10 mm. |
Calyculi | of 8–10 usually spreading, lance-linear to lanceolate, sometimes ± foliaceous bractlets or bracts 10–20(–75) mm, margins entire or incised, ciliate, abaxial faces ± hispid at bases. |
Heads | in ± corymbiform arrays. |
Cypselae | olivaceous green, ± flattened, unequally 3–4-angled, cuneate, outer 5–6 mm, inner 6–7 mm, margins antrorsely to retrorsely barbed, apices truncate to concave, faces weakly striate, glabrous or sparsely puberulent; pappi 0, or of (1–)3(–4) suberect, retrorsely barbed awns 2–4 mm. |
Bidens amplissima |
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Phenology | Flowering Aug–Oct. |
Habitat | Seasonal wetlands, borders of ponds, lakes, streams, estuaries |
Elevation | 0–100 m (0–300 ft) |
Distribution |
WA; BC
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Discussion | Of conservation concern. For decades, Bidens amplissima was known only from Vancouver Island; it is now known from southwestern British Columbia and northwestern Washington (F. R. Ganders et al. 2003). Occurrences in southern Manitoba and northwestern Nebraska may represent ephemeral introductions. The restricted natural range of B. amplissima has stimulated interest in it, the addition of it to rare plant lists, and the consideration of need for protected sites where it grows. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 216. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Bidens |
Sibling taxa | |
Synonyms | B. cernua var. elata, B. elata |
Name authority | Greene: Pittonia 4: 268. (1901) |
Web links |