Erigeron karvinskianus |
Erigeron divergens |
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erigeron karvinskianus, Karwinsky's fleabane, Latin American fleabane, Mexican fleabane, Santa Barbara daisy, Spanish daisy |
branching fleabane diffuse daisy, diffuse daisy, diffuse fleabane, spreading fleabane |
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Habit | Perennials, often short-lived, 10–100 cm; fibrous- or taprooted, caudices woody, usually simple, stems sometimes rooting adventitiously. | Annuals or short-lived perennials, (7–)12–40(–70) cm; taprooted, caudices simple if perennial. |
Stems | erect to sprawling or decumbent (small leaf tufts in axils of larger leaves), sparsely strigose to glabrate, eglandular. |
(single or multiple from bases) erect to ascending, densely and evenly puberulous-hirsutulous (hairs spreading to spreading-descending or -ascending, often crinkly, bases not thickened), minutely glandular at least distally, usually throughout. |
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. |
basal (usually deciduous) and cauline; basal blades obovate-spatulate, 10–70 × 4–-14 mm; cauline gradually reduced distally, margins entire or with 2–3 pairs of teeth or lobes, faces hirsute to loosely strigoso-hirsute, sometimes sparsely glandular. |
Involucres | 2.5–3.5 × 7–10 mm. |
3–4 × (5–)7–11 mm. |
Ray florets | 45–80; corollas 5–8 mm, laminae not or slightly coiling, white, sometimes drying pinkish. |
75–150; corollas white, drying lilac, without abaxial midstripe, (2–)4–9.5 mm, laminae not coiling or reflexing (remaining relatively straight). |
Disc corollas | 2–3.1 mm. |
1.8–2.3 mm (throats indurate and slightly inflated). |
Phyllaries | in 3–4 series, sparsely strigose to hirsuto-villous or glabrate, sometimes minutely glandular. |
in 3–4 series, hirsute, minutely glandular. |
Heads | 1–5 (usually from branches distal to midstem). |
(in early season, 1–)5–100+ (buds nodding). |
Cypselae | 1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–27 bristles. |
0.9–1.2 mm, 2-nerved (nerves whitish), faces sparsely strigose; pappi: outer of setae or scales, inner of 6–9(–12) bristles. |
2n | = 18, 27, 36 (from Mexico, Central America, South America). |
= 18, 27, 36. |
Erigeron karvinskianus |
Erigeron divergens |
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Phenology | Flowering Apr–Aug. | Flowering (Feb–)Apr–Oct. |
Habitat | Moist, disturbed sites, shaded rock walls, cement cracks | Gravelly or sandy flats, riverbanks, meadows, disturbed sites, desert scrubland to grasslands, saltbush, blackbrush, sagebrush, pinyon-juniper, juniper-oak, oak, and ponderosa pine woodlands |
Elevation | 300–1100 m (1000–3600 ft) | 60–2000(–2700) m (200–6600(–8900) 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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AZ; CA; CO; ID; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora, and southward)
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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.) |
Polyploidy and agamospermy apparently are common in Erigeron divergens and contribute to the variability and, probably to some extent, the polymorphism characteristic of this species. Diploids appear to be scattered through the range of the species, at least in its southern part. The form of Erigeron divergens with persistent, deeply pinnatifid basal leaves with relatively long petioles and tendency toward perenniality (woody taproots) has been named E. accedens [occurs at 200–1000(–1200) m and flowers Feb–Apr(–May)]. Such plants have sometimes been identified as E. lobatus, and it is possible that they may have originated as hybrids with it; in most ways they are similar to E. divergens and apparently intergrade with it. The E. accedens form occurs in California, Arizona, New Mexico, southwest Texas, Baja California, northern Sonora, Durango, and Chihuahua, apparently sympatrically with more typical E. divergens, suggesting that the former is stabilized and self-reproductive (probably agamospermic). Available chromosome counts are triploid. Rare plants (e.g., E. incomptus) may have filiform rays barely extending past the involucre. Another common form of Erigeron divergens in the broad sense (mostly in Chihuahua, also southern Texas, New Mexico, and Arizona) has bowl-shaped plants with decumbent stems, a discrete taproot, persistent, lobed basal leaves, and solitary heads topping usually simple stems, and usually is early-season in phenology. Further comments related to variation in E. divergens are found under 163. Erigeron multiceps. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 337. | FNA vol. 20, p. 339. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. mucronatus | E. divaricatus, E. accedens, E. incomptus, E. solisaltator |
Name authority | de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 285. (1836) | Torrey & A. Gray: Fl. N. Amer. 2: 175. (1841) |
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