Erigeron modestus |
Erigeron karvinskianus |
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plains fleabane |
erigeron karvinskianus, Karwinsky's fleabane, Latin American fleabane, Mexican fleabane, Santa Barbara daisy, Spanish daisy |
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Habit | Perennials (sometimes flowering early and appearing annual or biennial), 8–40 cm; usually taprooted (taproots woody or lignescent, early season forms sometimes fibrous-rooted), caudices usually woody, sometimes branched. | Perennials, often short-lived, 10–100 cm; fibrous- or taprooted, caudices woody, usually simple, stems sometimes rooting adventitiously. |
Stems | (often multiple from bases; of previous year often persistent) ascending to spreading (proximally reddish in early season, sometimes proximally woody or lignescent), loosely strigose to villous (proximal hairs sometimes spreading), often sparsely glandular. |
erect to sprawling or decumbent (small leaf tufts in axils of larger leaves), sparsely strigose to glabrate, eglandular. |
Leaves | basal (often withering by late flowering) and cauline; blades oblanceolate to spatulate, 20–50(–100) × 3–7(–18) mm, gradually reduced distally, margins entire or with 1–2(–3) pairs of teeth, faces loosely strigose (hairs ascending), eglandular. |
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. |
Involucres | 3–4.5 × 6–9(–12) mm. |
2.5–3.5 × 7–10 mm. |
Ray florets | 24–65(–170); corollas white, often with abaxial midstripe, often drying lilac, 4–7(–11) mm, laminae not coiling or reflexing. |
45–80; corollas 5–8 mm, laminae not or slightly coiling, white, sometimes drying pinkish. |
Disc corollas | 1.7–3.1 mm (throats indurate and slightly inflated). |
2–3.1 mm. |
Phyllaries | in 2–3 series, sparsely to moderately hirsute, minutely glandular. |
in 3–4 series, sparsely strigose to hirsuto-villous or glabrate, sometimes minutely glandular. |
Heads | 1(–3+, –50 in later season, branches at first from midstem or proximally, later more distal). |
1–5 (usually from branches distal to midstem). |
Cypselae | 1.1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of (5–)12–17 bristles. |
1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–27 bristles. |
2n | = 27, 36. |
= 18, 27, 36 (from Mexico, Central America, South America). |
Erigeron modestus |
Erigeron karvinskianus |
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Phenology | Flowering (Mar–)Apr–Jun(–Oct). | Flowering Apr–Aug. |
Habitat | Rocky or gravelly sites, sand, clay, limestone, granite, sometimes deep sand, often with oak or oak-juniper, shrubland | Moist, disturbed sites, shaded rock walls, cement cracks |
Elevation | 200–1700(–2300) m (700–5600(–7500) ft) | 300–1100 m (1000–3600 ft) |
Distribution |
AZ; KS; NM; OK; TX; Mexico (Coahuila, Chihuahua, Nuevo Leon)
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CA; Mexico; Central America [Introduced in North America; introduced in West Indies, South America, Europe, Africa, Pacific Islands, Australia]
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Discussion | Erigeron modestus is a polyploid complex apparently incorporating genes from E. flagellaris, E. tracyi, elements of E divergens, and the Mexican E. pubescens Kunth; arbitrary identifications may be necessary. In most of its range in Texas, E. modestus is not sympatric with any of those other taxa. Forms flowering in early season (Mar–Apr) often have stems red at the bases, dentate basal leaves 30–60(–100) × 5–10(–18) mm, and single, relatively large heads (involucres 9–12 mm diam, ray florets 50–170, corollas 6.5–11 mm) on ebracteate peduncles 5–15 cm. Later season plants have nearly intricately branched stems with more numerous, much smaller, diffusely arranged heads. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 20, p. 341. | FNA vol. 20, p. 337. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. lobatus var. warnockii, E. plateauensis, E. warnockii | E. mucronatus |
Name authority | A. Gray: Mem. Amer. Acad. Arts, n. s. 4: 68. (1849) | de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 285. (1836) |
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