Erigeron grandiflorus |
Erigeron sceptrifer |
|
---|---|---|
large-flower daisy, large-flower fleabane, onestem fleabane, Rocky Mountain alpine fleabane |
scepter-bearing fleabane |
|
Habit | Perennials, 2–25 cm; rhizomatous, fibrous-rooted, caudices or rhizomes crownlike or branches relatively short and thick. | Annuals, 3–8 cm; taprooted. |
Stems | erect to decumbent-ascending, sparsely to moderately pilose to villoso-hirsute, often stipitate-glandular over all or part. |
(single or multiple) ascending from bases, moderately hirsuto-hirtellous (hairs spreading-ascending, mostly on ribs, bases thickened), minutely glandular. |
Leaves | basal (persistent) and cauline (petioles equaling or shorter than blades); blades oblanceolate to obovate or spatulate, 10–60(–90) × 3–8(–14) mm, cauline abruptly or gradually reduced distally, margins entire (apices rounded), faces sparsely hirsutulous or villous to sparsely strigose or glabrate, sometimes sparsely glandular. |
mostly cauline; blades linear to linear-oblanceolate, 10–30 × 0.5–1.5 mm (proximal rarely 4 mm wide), margins entire or proximalmost with 1–2 pairs of teeth, faces loosely ascending-strigose, minutely glandular. |
Involucres | 5–8(–10) × 8–20 mm. |
3–3.5 × 4–6 mm. |
Ray florets | 50–130; corollas blue to pink or purplish, rarely white, 7–11(–15) mm (mostly 1–2 mm wide), laminae coiling. |
(60–)85–130(–195); corollas white, drying purple, less often pink to bluish, 3.8–5 mm, laminae downward curving-reflexing. |
Disc corollas | 2.4–4(–5) mm. |
1.8–2.3 mm (throats indurate and inflated). |
Phyllaries | in 2–3 series (green or purplish), moderately to densely woolly-villous (hairs flattened, cross walls sometimes reddish), minutely glandular at least apically. |
in 3–4 series, sparsely hirsuto-strigose, minutely glandular. |
Heads | 1. |
20–50+ in loosely corymbiform arrays (buds erect). |
Cypselae | 1.8–2.4 mm, 2-nerved, faces strigose; pappi: outer of setae, inner of (7–)10–18(–22) bristles. |
0.6–0.7 mm, 2-nerved (nerves orange), faces sparsely strigose; pappi: outer 0 or scales or setae, inner of 9–14 bristles. |
2n | = 18, 27. |
|
Erigeron grandiflorus |
Erigeron sceptrifer |
|
Phenology | Flowering Jul–Aug(–Sep). | Flowering Jul–Oct. |
Habitat | Rocky sites, meadows, alpine or near timberline | Grasslands with scattered juniper, oak, or oak-pine |
Elevation | 2900–4200 m (9500–13800 ft) | 1300–2100 m (4300–6900 ft) |
Distribution |
AZ; CO; ID; MT; NM; OR; UT; WY; AB; BC
|
AZ; Mexico (Chihuahua, Sonora) |
Discussion | S. A. Spongberg (1971) recognized only the triploid populations as Erigeron grandiflorus and assigned the diploid ones to E. simplex. He hypothesized that the triploids incorporate genomic elements from an ancestor other than E. simplex. Based on his comments and annotations, however, triploids in southern Canada and the western United States apparently differ from the much more widespread diploids only quantitatively, having involucres and florets at the higher end of size ranges. Morphologic distinctions between the ploidal races do not provide a basis for consistent distinction. Spongberg (p. 200) also noted that “because of the intergrading of morphologic features of plants of Erigeron grandiflorus...the single most important criterion indicative of this taxon is highly irregular [in shape] and greatly abortive pollen.” These pollen features result from meiotic anomalies associated with the triploid condition. Specimen citations by A. Cronquist (1947) for Erigeron grandiflorus were mostly from collections of the species treated here as E. porsildii. He also cited two collections from southwestern Alberta; those and the type collection of E. grandiflorus (from the same region) are disjunct by more than 1500 kilometers from the more northern range of E. porsildii and instead lie at the northern extremity of the range of what previously has generally been identified as E. simplex. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Erigeron sceptrifer is similar in habit to E. divergens; it has stem hairs only along the ribs, erect (versus nodding) buds, pappi of more bristles, without a conspicuous outer series, reflexing ray laminae, and orange cypselar nerves. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 324. | FNA vol. 20, p. 337. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. simplex | |
Name authority | Hooker: Fl. Bor.-Amer. 2: 18, plate 123. (1834) | G. L. Nesom: Phytologia 69: 248. (1990) |
Web links |