Erigeron nivalis |
Erigeron versicolor |
|
---|---|---|
bitter daisy, bitter fleabane, northern daisy, snow fleabane, snow fleabane daisy, snowbed fleabane |
bald-fruit fleabane, changing fleabane |
|
Habit | Biennials or short-lived perennials, 5–25(–35) cm; usually fibrous-rooted, sometimes taprooted, caudices simple or branched, sometimes weakly short-rhizomatous. | Annuals or rarely short-lived perennials, 12–50(–80) cm; taprooted or rarely fibrous-rooted. |
Stems | erect to basally ascending, sometimes sparsely hirsuto-villous, minutely glandular. |
(single or multiple from bases) usually basally ascending, strigose to villous, often slightly and minutely stipitate-glandular near to heads. |
Leaves | basal (persistent) and cauline (petiole margins coarsely ciliate); basal blades oblanceolate to spatulate, 20–60 × 2–6(–10) mm; cauline gradually reduced distally, margins entire or rarely with 1–2 pairs of shallow teeth, faces sparsely hirsuto-strigose, eglandular. |
basal (usually not persistent) and cauline; blades narrowly lanceolate to oblanceolate, basal (5–)20–50 × 3–9 mm, cauline gradually reduced distally, margins entire or proximal shallowly crenate to serrate with 1–3 pairs of teeth, faces sparsely strigose, eglandular. |
Involucres | 5–6 × 8–11 mm. |
2.5–4 × (3–)5–9 mm. |
Ray florets | 60–110; corollas white, 2.5–5(–7) mm, laminae not reflexing or coiling. |
|
Ray (pistillate) florets | in 2 series; outer 40–70, corollas white to pinkish 5.5–7 mm, laminae (filiform) erect, not coiling or reflexing; inner many fewer than outer series, tubular, elaminate. |
|
Disc corollas | 4.4–5.5 mm. |
1.2–2 mm (throats slightly indurate and inflated). |
Phyllaries | in 2–3(–4) series (inner apices attenuate to caudate), sparsely hirsuto-villous or glabrous, minutely glandular. |
in 2–3 series (margins scarious at least in inner), sparsely hirsute, minutely glandular. |
Heads | 1–6(–8) in corymbiform arrays (on curved-ascending peduncles). |
(1–)5–ca. 100. |
Cypselae | 2–2.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of (12–)14–21 (accrescent) bristles. |
(0.5–)0.8–1.3 mm, 2-nerved, faces glabrous or sparsely strigose; pappi: outer of minute, blunt scales or fimbriate crowns (to 0.15 mm), inner 0. |
2n | = 18. |
= 18, 27, 36. |
Erigeron nivalis |
Erigeron versicolor |
|
Phenology | Flowering May–Aug. | Flowering Apr–Jun(–Oct). |
Habitat | Rocky sites, gravel bars and banks, roadsides, meadows, open woods, up to subalpine areas with spruce in Rocky Mountains | Scattered and local, open sites, usually in moist soil, edges of low or marshy areas, stream edges, ditches |
Elevation | 1200–3700 m (3900–12100 ft) | 100–400 m (2600–2900 m, Ariz.) (300–1300 ft (8500–9500 ft, Ariz.)) |
Distribution |
AK; CA; CO; ID; MT; NM; OR; UT; WA; WY; AB; BC; NT; YT
|
AZ; NM; TX; Mexico |
Discussion | Erigeron nivalis usually has been treated as an infra-specific taxon within E. acris; the two are broadly sympatric in the northwestern United States and Canada without obvious intergrades. Both occur over a wide range of elevations and in similar habitats. Erigeron nivalis probably occurs in Nevada; it has not been taxonomically distinguished there. Erigeron scotteri was regarded by E. H. Moss and J. G. Packer (1983) as a synonym of E. acris (presumably var. debilis = E. nivalis; the heads are relatively small and borne singly). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
In Arizona, Erigeron versicolor grows in meadows, along creeks, and in pine-aspen-spruce areas. Erigeron versicolor is distinguished by its annual duration, nodding buds, conic receptacles, broad phyllaries, and pappi of only minute crowns. The species appears to be disjunctly divided among three regions in the United States and Mexico (D. C. D. De Jong and G. L. Nesom 1996), and habitats vary widely. This is an unusual distribution. There is much variation in duration, root type, orientation of stem pubescence, elaboration of the pappus crown, and achene vestiture, and this morphologic variation does not appear to be strongly correlated with geography. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 322. | FNA vol. 20, p. 344. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. acris subsp. debilis, E. acris var. debilis, E. angulosus subsp. debilis, E. debilis, E. elatus var. bakeri, E. jucundus, E. scotteri, Trimorpha acris var. debilis | Achaetogeron versicolor, Achaetogeron chihuahuensis, E. geiseri var. calcicola, E. gilensis, E. mimegletes |
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 311. (1841) | (Greenman) G. L. Nesom: Sida 9: 225. (1982) |
Web links |
|