Erigeron asperugineus |
Erigeron tracyi |
|
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Idaho daisy, Idaho fleabane |
running fleabane |
|
Habit | Perennials, 2–20 cm; slenderly taprooted, caudices usually branched. | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. |
Stems | usually decumbent-ascending, moderately to densely hirsutulous to hirtellous (hairs usually deflexed), 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. |
Leaves | basal (persistent) and cauline; basal blades 1-nerved or weakly 3-nerved, spatulate, rhombic-elliptic to obovate or oblanceolate (often folding), 20–50(–80) × 3–10(–13) mm; cauline gradually or abruptly reduced and linear distally (bases abruptly contracted to petioles), margins entire, faces moderately to densely hirsutulous, 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. |
Involucres | 5–9 × 7–14 mm. |
3.5–4.5(–6) × 6–9(–12) mm. |
Ray florets | 10–25; corollas deep blue or violet to rose-purple, 5–10 mm, laminae not coiling or reflexing. |
60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
Disc corollas | 4.2–6.3 mm. |
2–3 mm (throats indurate and slightly inflated). |
Phyllaries | in 3–4 series (tips and margins often purple), sparsely to moderately hirsutulous, densely minutely glandular. |
in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
Heads | 1(–2). |
1(–3 rarely, from midstem or proximal branches). |
Cypselae | 2.5–3.1 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 20–30 bristles. |
0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
2n | = 27. |
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Erigeron asperugineus |
Erigeron tracyi |
|
Phenology | Flowering Jul–Aug. | Flowering Mar–Oct. |
Habitat | Rocky or gravelly slopes and ridges, talus, sagebrush or meadow edges, limber pine, whitebark pine, fir-pine | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine |
Elevation | (2100–)2500–3300 m ((6900–)8200–10800 ft) | 700–2300(–2400) m (2300–7500(–7900) ft) |
Distribution |
ID; MT; NV; UT
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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 | Erigeron asperugineus sometimes is very similar in aspect to E. clokeyi var. pinzliae; the latter differs in its narrower leaves, coarsely ciliate petioles, broader and non-reflexing rays, and shorter cypselae. (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.) |
Source | FNA vol. 20, p. 306. | FNA vol. 20, p. 340. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | Aster asperugineus | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus |
Name authority | (D. C. Eaton) A. Gray: Notes Compositae, 91. (1880) | Greene: Pittonia 5: 59. (1902) |
Web links |