Erigeron cervinus |
Erigeron tracyi |
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Siskiyou daisy, Siskiyou fleabane |
running fleabane |
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Habit | Perennials, (10–)15–30 cm; rhizomatous, fibrous-rooted, caudices or rhizomes sometimes with relatively short or elongate, slightly woody branches. | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. |
Stems | ascending-erect, glabrous, sometimes minutely glandular distally. |
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 (often persistent) and cauline; basal blades spatulate to obovate or oblanceolate, (10–)40–80(–120) × 4–12(–15) mm; cauline equal-sized or gradually reduced distally (bases sometimes weakly subclasping), margins entire, faces glabrous, 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 | 5–7 × 9–14 mm. |
3.5–4.5(–6) × 6–9(–12) mm. |
Ray florets | 20–45; corollas blue to purplish, 7–10 mm (mostly 1.5–3 mm wide), laminae coiling. |
60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
Disc corollas | 3.5–4.9 mm. |
2–3 mm (throats indurate and slightly inflated). |
Phyllaries | in 2–3(–4) series, glabrous, densely minutely glandular. |
in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
Heads | 1(–4). |
1(–3 rarely, from midstem or proximal branches). |
Cypselae | 1.5–1.7 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–15 bristles. |
0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
2n | = 27. |
|
Erigeron cervinus |
Erigeron tracyi |
|
Phenology | Flowering (May–)Jun–Aug(–Sep). | Flowering Mar–Oct. |
Habitat | Open, rocky slopes and streamsides, seeps, crevices in walls, meadows, pine to fir woods, chaparral, sometimes over serpentine | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine |
Elevation | (50–)900–2300 m ((200–)3000–7500 ft) | 700–2300(–2400) m (2300–7500(–7900) ft) |
Distribution |
CA; OR
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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 | Plants with relatively elongate basal leaves and cauline leaves little reduced distally (identified as Erigeron delicatus) are much different in general aspect; intermediates bridge the morphologic extremes. (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. 335. | FNA vol. 20, p. 340. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. delicatus | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus |
Name authority | Greene: Pittonia 3: 163. (1897) | Greene: Pittonia 5: 59. (1902) |
Web links |