Erigeron quercifolius |
Erigeron radicatus |
|
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oak-leaf fleabane |
Hooker's fleabane, Huber's fleabane, tap-root fleabane |
|
Habit | Perennials, (1–)2–6(–12) cm; taprooted, caudices branches relatively short, thick. | |
Stems | erect to basally ascending (green proximally), proximally villous to villoso-hirsute, distally loosely strigose to hirsute, eglandular. |
erect, strigose to sparsely or densely short-villous (hairs loosely appressed to ascending or spreading), eglandular. |
Leaves | basal (persistent) and cauline; basal blades oblanceolate to obovate or spatulate, 15–110(–150) × 4–25(–30) mm, margins serrate or crenate to pinnately lobed, faces hirsute to villous, eglandular; cauline blades becoming oblong, gradually reduced distally (reduced to bracts or 0 proximal to arrays, clasping to subclasping). |
mostly basal (persistent) (eciliate or weakly ciliate proximally); blades 1-nerved linear to narrowly oblanceolate or subspatulate, (5–)10–50(–60) × 0.8–2.5 mm (bases gradually narrowing), margins entire (apices obtuse to rounded), abaxial faces glabrate or glabrous, shiny, adaxial sparsely, loosely strigose, eglandular; cauline mostly on proximal 1/2–1/3 of stems (absent in some high elevation forms), abruptly or gradually reduced distally. |
Involucres | 2.5–4 × 4.5–10 mm. |
(3–)4–6(–8) × (5–)8–12(–15) mm. |
Ray florets | 100–150; corollas usually blue, sometimes white to pink, 4–6 mm, laminae not coiling or reflexing. |
(12–)20–44(–85); corollas white, less commonly purplish, 4–7(–8) mm, laminae coiling. |
Disc corollas | 1.5–2.8 mm. |
(2–)2.5–3.5(–4) mm. |
Phyllaries | in (2–)3–4 series (sometimes basally connate), strigose to hirsuto-villous, eglandular or sparsely minutely glandular. |
in 2–3(–4) series (subequal), villosulous to villoso-hirsutulous (hairs usually with purplish cross walls at least in basal cells), minutely glandular apically or eglandular. |
Heads | (1–)4–16(–50) in corymbiform arrays (from branches distal to midstem). |
1. |
Cypselae | 0.6–0.9 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 10–15 bristles. |
2.1–2.5 mm, 2-nerved, faces sparsely strigose; pappi: outer of scales, inner of (6–)7–11 (readily falling) bristles. |
Winter | annuals, biennials, or short-lived perennials, 10–60 cm; fibrous-rooted, caudices simple. |
|
2n | = 18. |
|
Erigeron quercifolius |
Erigeron radicatus |
|
Phenology | Flowering (Feb–)Mar–Jun. | Flowering May–Aug. |
Habitat | Sandy sites, shell rock, roadsides, ditches, fields, areas of pine flatwoods | Rocky slopes, ridges, and summits, ledges and crevices, outcrops and talus, usually limestone, alpine tundra |
Elevation | 0–15 m (0–0 ft) | (1400–)1600–2800(–3400) m ((4600–)5200–9200(–11200) ft) |
Distribution |
FL; GA; NC; SC; VA; West Indies (Bahama Islands)
|
CO; ID; MT; ND; NE; SD; UT; WY; AB; SK
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Discussion | Erigeron quercifolius is primarily of the Atlantic coastal plain. Putative records from Alabama westward to Texas are based on specimens of E. philadelphicus or E. tenuis. Erigeron tenuis sometimes closely approaches E. quercifolius in overall appearance; it is more closely related to E. strigosus. Convergent plants of E. tenuis differ from E. quercifolius in their non-clasping cauline leaves, lanceolate (versus oblanceolate to obovate) phyllaries, and slightly longer cypselae (1–1.2 mm versus 0.6–0.9 mm). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Collections of Erigeron radicatus often have been identified as E. ochroleucus var. scribneri; E. radicatus is distinctive in its branched caudex, villous cauline vestiture, more reduced leaf vestiture, involucral vestiture of hairs with purple cross walls, shorter disc corollas, and relatively few, readily falling pappus bristles. Erigeron radicatus often is essentially scapiform at relatively high elevation (2700–3400 m) in Idaho, Montana, Utah, and Wyoming; more eastern populations in the Great Plains, at lower elevations (1400–2600 m), have leafier stems but are hardly different in other features. Plants of some populations in Albany and Carbon counties, Wyoming, produce atypically shorter rays. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 320. | FNA vol. 20, p. 294. |
Parent taxa | Asteraceae > tribe Astereae > Erigeron | Asteraceae > tribe Astereae > Erigeron |
Sibling taxa | ||
Synonyms | E. huberi, E. macounii | |
Name authority | Lamarck: in J. Lamarck and J. Poiret, Tabl. Encycl. 3: 258. (1796) | Hooker: Fl. Bor.-Amer. 2: 17, plate 122. (1834) |
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