Erigeron salishii |
Erigeron tracyi |
|
---|---|---|
salish daisy, salish fleabane, star peak fleabane |
running fleabane |
|
Habit | Perennials, 1.5–5(–7) cm (forming densely compact cushions); taprooted, caudex branches rhizomelike, relatively numerous, short, and slender. | Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. |
Stems | erect (simple, scapiform), sparsely to densely hirsuto-villous, minutely glandular. |
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; petioles linear, 0.5–1 mm wide); blades obovate-spatulate, 3–16 × 3–6 mm (bases abruptly expanded), margins mostly 3-lobed, rarely entire or 2-lobed (lobes 2–8 mm, oblong to ovate or obovate, rounded), ultimately entire, coarsely ciliate, faces sparsely to densely hirsute, ± minutely glandular. |
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 × 8–11 mm. |
3.5–4.5(–6) × 6–9(–12) mm. |
Ray florets | 15–32; corollas white to bluish, 6–10 mm, laminae not coiling or reflexing (spreading). |
60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. |
Disc corollas | 3.2–4.5 mm. |
2–3 mm (throats indurate and slightly inflated). |
Phyllaries | in 2–3 series (commonly purplish, sometimes at tips only), sparsely to densely hirsuto-villous to villous (hairs usually with colored cross walls), minutely glandular. |
in 3–4 series, sparsely to moderately hirsute, minutely glandular. |
Heads | 1. |
1(–3 rarely, from midstem or proximal branches). |
Cypselae | 2–2.6 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–21 bristles. |
0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. |
2n | = 18. |
= 27. |
Erigeron salishii |
Erigeron tracyi |
|
Phenology | Flowering Jul–Sep. | Flowering Mar–Oct. |
Habitat | Cliffs and gravelly slopes, ridges, ledges | Desert scrub, grassy slopes, oak chaparral, pinyon-juniper woodlands, Douglas fir-ponderosa pine |
Elevation | 1500–2150 m (4900–7100 ft) | 700–2300(–2400) m (2300–7500(–7900) ft) |
Distribution |
WA; BC
|
AZ; CO; KS; NM; NV; OK; TX; UT; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora, Zacatecas)
|
Discussion | Of conservation concern. The compactly cespitose, cushionlike habit of Erigeron salishii may obscure the slender, loose branches of the caudex in herbarium specimens. The species otherwise is similar to E. vagus; the leaves of E. salishii are mostly smaller and the hairs thinner and looser (villous) compared to those of E. vagus. (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. 301. | FNA vol. 20, p. 340. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. cinereus, E. colomexicanus, E. commixtus, E. divergens var. cinereus | |
Name authority | G. W. Douglas & Packer: Canad. J. Bot. 66: 414, fig. 1. (1988) | Greene: Pittonia 5: 59. (1902) |
Web links |