Erigeron caespitosus |
Erigeron flagellaris |
|
---|---|---|
tuft daisy, tuft fleabane |
trailing fleabane, whiplash daisy |
|
Habit | Perennials, 5–25(–30) cm; taprooted, caudices relatively thick, usually branched. | |
Stems | decumbent-ascending (greenish proximally), usually densely hirsute to hirtellous (hairs spreading to deflexed, gradually attenuate, basal cells erect), sometimes strigose (in Saskatchewan and Yukon), eglandular. |
first erect (greenish proximally; usually single, simple), then producing herbaceous, leafy, prostrate runners (usually with rooting plantlets at tips, populations often becoming clonal mats), strigose (often sparsely; hairs antrorsely appressed, consistent in orientation), sometimes slightly glandular distally. |
Leaves | basal (persistent) and cauline; basal blades (1–)3-nerved, narrowly oblanceolate to spatulate, (10–)20–90(–120) × 2–15 mm, margins entire (apices rounded to obtuse), faces densely hirtellous, eglandular; cauline blades oblong-ovate to linear, ± reduced distally. |
basal (often persistent) and cauline; basal blades broadly oblanceolate to elliptic, 20–55 × 3–9 mm; cauline abruptly reduced distally, margins entire or dentate, faces strigose, eglandular. |
Involucres | 4–7 × 9–18 mm. |
3–5 × 6–13 mm. |
Ray florets | 30–100; corollas white to bluish, 5–15 mm, laminae coiling. |
40–125; corollas white, often with an abaxial midstripe, often drying lilac, 4–10 mm, laminae not coiling or reflexing. |
Disc corollas | 3–4.4 mm. |
2–3.5 mm. |
Phyllaries | in 3–4 series, densely hirsuto-canescent to hirtellous (hairs spreading), moderately minutely glandular. |
in 2–3 series, strigose to loosely hirsute, minutely glandular. |
Heads | 1–4 (branches from distal 1/2 of stem). |
1(–3, on proximal branches). |
Cypselae | 1.7–2.2 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae or scales, inner of 15–25 bristles. |
0.8–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 10–17 bristles. |
Biennuals | or short-lived perennials, 3–15 cm; usually fibrous-rooted, sometimes taprooted, caudices lignescent, rarely branched. |
|
2n | = 18, 36. |
= 18, 27, 36, 45, 54. |
Erigeron caespitosus |
Erigeron flagellaris |
|
Phenology | Flowering Jun–Aug. | Flowering May–Aug(–Sep). |
Habitat | Rocky or sandy, grassy hills, sagebrush-aspen, pinyon-juniper, to spruce and tundra northward | Meadows and grassy slopes, often moist, open areas in grasslands, pinyon pine, oak-pine, pine, aspen, and spruce-fir |
Elevation | 1300–3000(–3600) m (4300–9800(–11800) ft) | (1700–)2100–3600 m ((5600–)6900–11800 ft) |
Distribution |
AK; AZ; CO; ID; MT; ND; NE; NM; SD; UT; WA; WY; AB; BC; MB; SK; YT
|
AZ; CA; CO; ID; KS; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; Mexico
|
Discussion | Erigeron caespitosus as recognized here is highly variable and perhaps justifiably could be divided into more than one taxon. Plants at lower elevations tend to produce tall stems branching above the middle and long, white rays. At higher elevations, especially in Idaho, western Montana, Utah, and Wyoming, stems tend to be shorter and simple and the rays commonly are blue to violet. In the Bitterroot Mountains (Ravalli and Deerlodge counties, Montana), short-stemmed, blue-rayed plants also have strigose cauline vestiture (in contrast to typically deflexed-hirtellous stems); these vestiture variants occur in the same area with plants apparently similar in all other features. Strigose populational variants also occur in Saskatchewan and Yukon, and E. abajoensis, largely distinguished by strigose cauline vestiture, might be considered a regional variant of E. caespitosus. In eastern Idaho and southwestern Montana, plants of E. caespitosus are commonly encountered with cauline leaves obovate and distinctly subclasping. Plants with strongly 3-nerved basal leaves occur in Carbon and Gallatin counties, Montana. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Early season forms of Erigeron flagellaris may consist of a basal rosette and a single, erect, scapiform, monocephalous stem; leafy runners usually develop quickly. Many polyploids of this species are indistinguishable from diploids; some polyploids have features suggestive of genetic influence of E. tracyi. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 283. | FNA vol. 20, p. 341. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. nudiflorus | |
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 307. (1840) | A. Gray: Mem. Amer. Acad. Arts, n. s. 4: 68. (1849) |
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