Erigeron karvinskianus |
Erigeron compositus |
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erigeron karvinskianus, Karwinsky's fleabane, Latin American fleabane, Mexican fleabane, Santa Barbara daisy, Spanish daisy |
cut-leaf daisy, cut-leaf fleabane, dwarf mountain fleabane, fern-leaf fleabane, trifid mountain fleabane, vergerette à feuilles segmentées |
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Habit | Perennials, often short-lived, 10–100 cm; fibrous- or taprooted, caudices woody, usually simple, stems sometimes rooting adventitiously. | Perennials, 5–15(–25 cm); taprooted, caudices simple or branches usually relatively thick and short, rarely slender and rhizomelike, covered with persistent leaf bases. |
Stems | erect to sprawling or decumbent (small leaf tufts in axils of larger leaves), sparsely strigose to glabrate, eglandular. |
erect (simple, ± scapiform), sparsely hispido-pilose, minutely glandular. |
Leaves | basal (and proximal cauline withering by flowering) and cauline; cauline blades elliptic to obovate, mostly 10–40(–50) × 5–13 mm, usually relatively even-sized along stems, margins entire or with 1–2 distal pairs of acute, mucronulate teeth or lobes, faces sparsely and loosely strigose to hirsuto-villous, eglandular. |
mostly basal (persistent); blades spatulate to obovate-spatulate, 5–50(–70) × (2–)4–12 mm, margins (1–)2–3(–4)-ternately lobed or dissected, cauline bractlike, mostly entire, faces densely hispiduloso-puberulent to glabrate, minutely glandular. |
Involucres | 2.5–3.5 × 7–10 mm. |
5–10 × 8–20 mm. |
Ray florets | 45–80; corollas 5–8 mm, laminae not or slightly coiling, white, sometimes drying pinkish. |
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Ray (pistillate) florets | 20–60; corollas white to pink or blue, usually 6–12 mm, often reduced to tubes (heads disciform), laminae not coiling or reflexing. |
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Disc corollas | 2–3.1 mm. |
3–5 mm. |
Phyllaries | in 3–4 series, sparsely strigose to hirsuto-villous or glabrate, sometimes minutely glandular. |
in 2–3 series (purple-tipped), hirsute (hairs spreading), minutely glandular. |
Heads | 1–5 (usually from branches distal to midstem). |
(sometimes disciform) 1. |
Cypselae | 1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–27 bristles. |
1.6–2.7 mm, 2-nerved, faces sparsely strigose-hirsute; pappi: outer usually of setae, sometimes 0, inner of 12–20 bristles. |
2n | = 18, 27, 36 (from Mexico, Central America, South America). |
= 18, 36, 45, 54. |
Erigeron karvinskianus |
Erigeron compositus |
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Phenology | Flowering Apr–Aug. | Flowering (May–)Jun–Aug. |
Habitat | Moist, disturbed sites, shaded rock walls, cement cracks | Sagebrush, rabbitbrush, aspen to aspen-fir, subalpine meadows, cliffs, talus, and boulders |
Elevation | 300–1100 m (1000–3600 ft) | (in e Canada, possibly Greenland and Arctic bridge gap, 10–200–)1800–4300 m ((in e Canada, possibly Greenland and Arctic bridge gap, 0–700–)5900–14100 ft) |
Distribution |
CA; Mexico; Central America [Introduced in North America; introduced in West Indies, South America, Europe, Africa, Pacific Islands, Australia]
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AK; AZ; CA; CO; ID; MT; ND; NV; OR; SD; UT; WA; WY; AB; BC; NF; NT; NU; QC; SK; YT; Greenland; e Asia (Russian Far East)
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Discussion | Erigeron karvinskianus is most abundant in tropical and subtropical regions; it is widely cultivated and escaped. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Correlations among ploidal level, breeding systems, and morphologic variation have been studied in detail in Erigeron compositus. Five informally designated population systems of diploids are geographically restricted (all of the northwestern United States and adjacent Canada) and primarily sexual, compared to the polyploids, which are agamospermous and apparently of hybrid origin, at least in some cases (R. D. Noyes et al. 1995; Noyes and D. E. Soltis 1996). Reduction in ray floret laminae usually is correlated with polyploidy. Plants with 1-ternately lobed leaves have been identified as var. glabratus, an element of variation that does not have a geographic pattern. Among closely related species, Erigeron compositus is the only one that produces strongly thickened caudex branches; occasional collections show a tendency toward the slender, loose branches characteristic of the other species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 337. | FNA vol. 20, p. 300. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. mucronatus | E. compositus var. discoideus, E. compositus var. glabratus, E. compositus var. multifidus, E. gormanii |
Name authority | de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 285. (1836) | Pursh: Fl. Amer. Sept. 2: 535. (1813) |
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