Erigeron caespitosus |
Erigeron vreelandii |
|
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tuft daisy, tuft fleabane |
sticky tall fleabane, Vreeland's erigeron |
|
Habit | Perennials, 5–25(–30) cm; taprooted, caudices relatively thick, usually branched. | Perennials 30–80 cm; rhizomatous to subrhizomatous, fibrous-rooted, caudices usually relatively short and few branched, 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. |
erect, sometimes sparsely pilose (hairs 1–2 mm), densely stipitate-glandular. |
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 (usually withering by flowering) and cauline; basal blades oblanceolate-spatulate, 30–80 × 5–20(–25) mm (bases usually clasping to subclasping), margins entire, faces glabrous, densely stipitate-glandular; cauline blades narrowly lanceolate to oblong-, ovate-, or elliptic-lanceolate, nearly even-sized distally or sometimes mid largest (continuing to immediately proximal to heads). |
Involucres | 4–7 × 9–18 mm. |
6–9 × 10–15(–18) mm. |
Ray florets | 30–100; corollas white to bluish, 5–15 mm, laminae coiling. |
75–150; corollas blue to lavender, 9–17 mm (ca. 1 mm wide), laminae coiling. |
Disc corollas | 3–4.4 mm. |
3–4 mm. |
Phyllaries | in 3–4 series, densely hirsuto-canescent to hirtellous (hairs spreading), moderately minutely glandular. |
in 2–3(–4) series, densely stipitate-glandular. |
Heads | 1–4 (branches from distal 1/2 of stem). |
1–15(–22) in corymbiform arrays. |
Cypselae | 1.7–2.2 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae or scales, inner of 15–25 bristles. |
1.7–2 mm, 2-nerved, faces sparsely strigose; pappi: outer of (conspicuous) scales, inner of 14–22 bristles. |
2n | = 18, 36. |
= 18. |
Erigeron caespitosus |
Erigeron vreelandii |
|
Phenology | Flowering Jun–Aug. | Flowering Jul–Sep(–Oct). |
Habitat | Rocky or sandy, grassy hills, sagebrush-aspen, pinyon-juniper, to spruce and tundra northward | Openings and open woods, oak-pine, ponderosa pine, pine-fir |
Elevation | 1300–3000(–3600) m (4300–9800(–11800) ft) | (1300–)1800–3100 m ((4300–)5900–10200 ft) |
Distribution |
AK; AZ; CO; ID; MT; ND; NE; NM; SD; UT; WA; WY; AB; BC; MB; SK; YT
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AZ; CO; NM; Mexico (Sonora)
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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 vreelandii is similar to E. speciosus in its perennial duration, tall stature, subclasping, spreading leaves nearly even-sized up the stems, corymbiform arrays, and blue rays; it is distinguished by the prominent vestiture of relatively long stipitate-glandular hairs. Intermediates apparently are formed between the two. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 283. | FNA vol. 20, p. 331. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. patens, E. platyphyllus, E. rudis | |
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 307. (1840) | Greene: Bull. Torrey Bot. Club 32: 125. (1905) |
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