Erigeron speciosus |
Erigeron arizonicus |
|
---|---|---|
aspen fleabane, showy daisy, showy fleabane, splendid fleabane |
Arizona fleabane |
|
Habit | Perennials, 30–80(–100) cm; rhizomatous, fibrous-rooted, caudices relatively thick. | Perennials, 8–40(–60) cm; rhizomatous, fibrous-rooted, caudices or rhizomes relatively thick, simple or branched, sometimes resembling a taproot. |
Stems | erect, glabrous or sparsely hirsuto-pilose (hairs 0.5–1 mm), often minutely glandular distally. |
erect to basally ascending, moderately to densely strigose to strigoso-hirsute or hirsute, eglandular. |
Leaves | basal (usually withering by flowering) and cauline; basal blades oblanceolate-spatulate, 30–80(–150) × 4–18(–28) mm, margins entire, often ciliate (main veins sometimes also), faces glabrous, eglandular or distal sparsely minutely glandular; cauline blades ovate to ovate-lanceolate, oblong-lanceolate, or lanceolate, nearly even-sized distally or sometimes mid largest (continuing to immediately below heads, bases usually clasping to subclasping). |
basal (commonly persistent) and cauline; basal blades often 3-nerved, spatulate, obovate to ovate, or elliptic, 20–150 × 5–25 mm, margins entire to shallowly serrate, faces loosely strigose, rarely minutely glandular; cauline blades slightly smaller than basal, relatively even-sized to peduncle bases, (bases subclasping) margins entire, becoming lanceolate (bases non-clasping) distally. |
Involucres | 6–9 × 11–22 mm. |
5–7 × 9–18 mm. |
Ray florets | 75–150; corollas blue to lavender, rarely whitish, 8–16 mm (mostly 1 mm wide), laminae slightly coiling at least at tips. |
25–80; corollas white, drying white or lilac-tinged, 8–10 mm (ca. 1 mm wide), laminae coiling at tips. |
Disc corollas | 4–5 mm. |
2.9–4 mm. |
Phyllaries | in 2–3(–4) series, usually glabrous, sometimes sparsely hirsuto-pilose, minutely glandular. |
in 3–4 series (greenish), moderately piloso-hirsute, densely minutely glandular (sometimes obscured by hairs). |
Heads | (2–)4–20 in corymbiform arrays. |
1–4(–6) (from branches on distal 1/3–1/2 of stem, peduncles distinct, 1.5–9 cm). |
Cypselae | 1.5–1.8 mm, 2(–4)-nerved, faces sparsely strigose; pappi: outer of setae, inner of 20–30 bristles. |
1.6–2.1 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–26 bristles. |
2n | = 18. |
|
Erigeron speciosus |
Erigeron arizonicus |
|
Phenology | Flowering Jul–Oct. | Flowering (May–)Jul–Sep(–Oct). |
Habitat | Dry or moist, gravelly or loamy soil, prairies, yellow pine, pine-fir, spruce-fir, aspen-spruce | Grassy slopes, openings, roadsides, sometimes rock crevices and ledges, oak-juniper to oak-pine, pine, pine-fir, Douglas fir, spruce-fir |
Elevation | (600–)900–3400 m ((2000–)3000–11200 ft) | (1800–)2100–2900(–3200) m ((5900–)6900–9500(–10500) ft) |
Distribution |
AZ; CO; ID; MT; NM; NV; OR; SD; UT; WA; WY; AB; BC; Mexico (Baja California)
|
AZ; NM; Mexico (Sonora)
|
Discussion | The population in Baja California is disjunct from the closest range in Arizona and northern Nevada. Plants glabrous and glandular on the phyllaries, stems, and leaves have been recognized as var. macranthus; they intergrade with hairier forms and do not show a coherent geographic pattern. Plants commonly identified as Erigeron subtrinervis var. conspicuus usually have stems sparsely hirsuto-pilose with hairs 1–1.5 mm, and the leaves commonly are ciliate on the margins and veins. As implied in the nomenclatural combination by Breitung, those plants are more similar to E. speciosus than to E. subtrinervis, and they apparently show part of the greater variability of E. speciosus in the northwestern part of its range (Alberta, British Columbia, Idaho, Montana, Oregon, Washington, and Wyoming), where more typical plants also occur. Erigeron speciosus and E. subtrinervis are sympatric over large parts of their ranges and appear to be at least partially reproductively isolated entities, although intermediates are frequently encountered. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 20, p. 330. | FNA vol. 20, p. 332. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | Stenactis speciosa, E. conspicuus, E. macranthus, E. speciosus var. conspicuus, E. speciosus var. macranthus, E. subtrinervis subsp. conspicuus, E. subtrinervis var. conspicuus | E. rusbyi |
Name authority | (Lindley) de Candolle: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 284. (1836) | A. Gray: Proc. Amer. Acad. Arts 19: 2. (1883) |
Web links |