Erigeron pulchellus |
Erigeron tracyi |
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hairy fleabane, poor robin fleabane, robin's plantain, robin's plantain fleabane |
running fleabane |
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Habit | Perennials, 15–60 cm; rhizomatous, fibrous-rooted, primary rhizomes relatively slender, producing slender, herbaceous, scale-leaved, stoloniform rhizomes (rhizomes often not collected). | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. | ||||||||
Stems | erect to ascending (usually abruptly dilated proximal to heads), villous (more densely so on proximal 1/2), eglandular. |
first erect (greenish proximally), then producing herbaceous, leafy, prostrate runners (stoloniform branches, sometimes with rooting plantlets at tips), densely hirsutulous (hairs spreading-deflexed, of relatively even lengths and orientations), sparsely minutely glandular. |
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Leaves | basal (persistent) and cauline; basal blades oblanceolate to obovate or suborbiculate, subspatulate, 20–130(–180) × 6–30(–50) mm; cauline gradually reduced distally (bases clasping and slightly auriculate), margins usually dentate to denticulate, rarely entire, faces sparsely to moderately hirsute to hirsuto-villous, sometimes glabrate or glabrous (especially adaxially), eglandular. |
mostly basal (persistent in early season); blades oblanceolate to spatulate (obovate-elliptic laminae), 10–30(–60) × 3–6(–12) mm, cauline abruptly reduced distally, margins entire, dentate, or lobed, faces densely hirsute, eglandular. |
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Involucres | 5–7 × 6–20 mm. |
3.5–4.5(–6) × 6–9(–12) mm. |
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Ray florets | 50–80(–100); corollas light blue to purplish, pink, or white, 6–10 mm, laminae coiling tardily at tips. |
60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
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Disc corollas | 4.5–6 mm. |
2–3 mm (throats indurate and slightly inflated). |
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Phyllaries | in 2–3(–4) series, sparsely to moderately hirsute to hirsuto-villous (cross walls not distinctly colored), minutely glandular to stipitate-glandular. |
in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
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Heads | 1–4(–9). |
1(–3 rarely, from midstem or proximal branches). |
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Cypselae | 1.3–1.8 mm, 2(–4)-nerved, faces sparsely strigose to glabrate or glabrous; pappi: outer 0 or of setae, inner of (22–)28–36 bristles. |
0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
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2n | = 27. |
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Erigeron pulchellus |
Erigeron tracyi |
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Phenology | Flowering Mar–Oct. | |||||||||
Habitat | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine | |||||||||
Elevation | 700–2300(–2400) m (2300–7500(–7900) ft) | |||||||||
Distribution |
AL; AR; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; ON; QC
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AZ; CO; KS; NM; NV; OK; TX; UT; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora, Zacatecas)
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Discussion | Varieties 3 (3 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
In March through June, plants of Erigeron tracyi produce leaves in a basal rosette usually with a single, erect, monocephalous, stem. Stoloniform branches are soon formed (often recognized on pressed specimens by the leaves mostly on one side of the branches), and by the end of the season (August through October), prostrate runners are usually evident, sometimes forming terminal, rooting plantlets. Erigeron tracyi is similar in habit to E. flagellaris, particularly in the herbaceous stolons or stoloniform branches; the stem pubescence of E. tracyi is different, the stolons much less commonly produce rooting plantlets at the tips, and the plants tend to be perennial with woody or lignescent caudices, although they are variable both in habit and duration. Apparent hybrids with E. modestus and E. flagellaris are occasionally encountered, and the most common form of E. tracyi is perhaps (speculative) a stabilized, apomictic hybrid between the latter and E. divergens. All chromosome counts thus far have shown E. tracyi to be triploid and asynaptic. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 327. | FNA vol. 20, p. 340. | ||||||||
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus | |||||||||
Name authority | Michaux: Fl. Bor.-Amer. 2: 124. (1803) | Greene: Pittonia 5: 59. (1902) | ||||||||
Web links |