Erigeron caespitosus |
Erigeron oxyphyllus |
|
---|---|---|
tuft daisy, tuft fleabane |
wand fleabane, wand-like fleabane daisy |
|
Habit | Perennials, 5–25(–30) cm; taprooted, caudices relatively thick, usually branched. | Perennials, 5–25 cm; taprooted, caudexlike branches relatively thick, woody. |
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. |
ascending (without axillary tufts of leaves), glabrous, eglandular. |
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. |
cauline (all commonly withering early in season); proximal blades oblanceolate to narrowly oblanceolate, 20–50(–100) × 0.5–1(–15) mm, abruptly reduced distally, becoming linear to filiform, mid and distal shorter than internodes, margins entire, usually eciliate, sometimes sparsely ciliate, faces sparsely and minutely strigose or glabrous, eglandular. |
Involucres | 4–7 × 9–18 mm. |
4–5(–6) × 7–12 mm. |
Ray florets | 30–100; corollas white to bluish, 5–15 mm, laminae coiling. |
12–27(–45); corollas white to lavender or blue, 6–9 mm, laminae slightly coiling at tips. |
Disc corollas | 3–4.4 mm. |
3–4 mm (throats slightly indurate, not inflated). |
Phyllaries | in 3–4 series, densely hirsuto-canescent to hirtellous (hairs spreading), moderately minutely glandular. |
in (3–)4–5 series (inner with (1–)3 orange veins, margins of inner narrow, scarious), usually glabrous, outer sometimes sparsely strigulose, minutely glandular. |
Heads | 1–4 (branches from distal 1/2 of stem). |
1(–3). |
Cypselae | 1.7–2.2 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae or scales, inner of 15–25 bristles. |
ca. 2 mm, 2–4(–5)-nerved, faces sparsely strigose; pappi: outer of setae, inner of 17–25 bristles. |
2n | = 18, 36. |
= 18. |
Erigeron caespitosus |
Erigeron oxyphyllus |
|
Phenology | Flowering Jun–Aug. | Flowering (Feb–)May–Jun(–Nov). |
Habitat | Rocky or sandy, grassy hills, sagebrush-aspen, pinyon-juniper, to spruce and tundra northward | Rocky hillsides around seeps or springs, canyons, cliff bases, among boulders, often with Acacia-Yucca-Coleogyne |
Elevation | 1300–3000(–3600) m (4300–9800(–11800) ft) | 700–1100 m (2300–3600 ft) |
Distribution |
AK; AZ; CO; ID; MT; ND; NE; NM; SD; UT; WA; WY; AB; BC; MB; SK; YT
|
AZ; CA; Mexico (Sonora) |
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.) |
Erigeron oxyphyllus is a member of sect. Pycnophyllum and is set apart from the rest of the section by its cauline leaves, sharply reduced in length distally, and by its more southeastern geographic range (versus the California-centered distribution of the rest of the section). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 283. | FNA vol. 20, p. 311. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 307. (1840) | Greene: Erythea 3: 20. (1895) |
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