Eurybia divaricata |
Eurybia eryngiifolia |
|
---|---|---|
aster à rameaux étalés, white wood-aster |
coyote-thistle aster, thistleleaf aster |
|
Habit | Plants 28–90(–120) cm, in ± dense clones (lacking sterile rosettes); rhizomes branched, elongate, becoming woody. | Plants 30–70 cm; in scattered individuals or small clumps, eglandular; rhizomes short, stout, or strong, woody caudices (roots fleshy). |
Stems | 1, erect, simple, flexuous, glabrate to sparsely puberulent proximally, densely puberulent distally. |
1–3+, erect, coarse, villous. |
Leaves | basal and cauline, thin, margins sharply serrate, teeth (6–15 per side) mucronulate, ciliate, apices acuminate, abaxial faces sparsely strigose or villous, particularly villous along veins, adaxial glabrescent to sparsely strigose, veins sparsely stipitate-glandular; basal and proximal withering by flowering, petiolate (petioles 20–70 mm), blades ovate, 19–65 × 17–60 mm, basal smaller than proximal, bases cordate (sinuses narrow, curved); cauline petiolate, petioles often ± winged (15–70 mm), blades ovate, 20–200 × 10–100 mm, bases cordate to rounded; distal (arrays) usually sessile, sometimes subpetiolate, blades ovate to lanceolate, 5–20 × 1–8 mm, bases rounded. |
strongly basal and cauline, coriaceous, margins indurate, entire to remotely spinose-serrate, remotely and obscurely scabridulous, spines indurate-margined or wholly indurate, finely parallel-veined with evident midnerves, apices acute, revolute, indurate, abaxial faces glabrous; basal and proximal cauline persistent (bases ± marcescent when leaves deciduous), petioles scarcely distinct, blades linear (grasslike), 70–350 × 3–8 mm, adaxial faces glabrous; cauline sessile, blades linear to lance-linear, 15–130 × 1.5–7 mm, progressively reduced and more spinose distally, adaxial faces progressively more villous distally. |
Peduncles | to 1.5 cm, densely hairy, eglandular; bracts 0(–2). |
± densely villous, sometimes sparsely stipitate-glandular distally; bracts 0–7, appressed, lanceolate, bases ± indurate, margins spinose, adaxial faces villous. |
Involucres | cylindro-campanulate, 4.2–6 mm, much shorter than pappi. |
campanulo-hemispheric, 9–12 mm, slightly shorter than pappi. |
Ray florets | 5–10(–12); corollas white, 6–12 × 1.5–2.2 mm. |
25–60; corollas white or pinkish, coiling, 10–20 × 1–2.1 mm. |
Disc florets | 12–19(–25); corollas yellow, 4.1–4.8(–5.5) mm, abruptly ampliate, tubes (2.3–2.6 mm) longer than campanulate throats (0.9–1.2 mm), lobes reflexed, lanceolate, 0.7–1.4 mm. |
115–260; corollas yellow, 5.5–7 mm, slightly ampliate, tubes shorter than tubular throats, lobes 0.75–1 mm, erect, lanceolate. |
Phyllaries | 25–30 in 4–5 series, inner purplish distally, oblong (outer) to lanceolate or linear-lanceolate (inner), strongly unequal, bases indurate, green zones in distal 1/2 (outer) to 1/3 or along distal midveins (inner), margins narrowly scarious, densely fimbriate-ciliate, apices rounded to acute, faces sparsely hairy, sometimes sparsely stipitate-glandular; outer 0.7–1.5 mm wide, lengths seldom more than 2.5 times widths. |
70–140 in 4–5 series, greenish, densely thick-nerved, lanceolate to linear (innermost), unequal, coriaceous, bases indurate and rounded (outer), margins entire, indurate or ± scarious, erose (inner), sometimes sparsely villoso-ciliate, ± densely stipitate-glandular, apices squarrose, green and often purplish-tinged, foliaceous, long-acuminate, adaxial faces villosulous, rarely also sparsely stipitate-glandular. |
Heads | 4–50(–100+) in ± flat-topped corymbiform arrays. |
1–11+, borne singly or in racemiform arrays, branches ascending to erect, stiff. |
Cypselae | brown, cylindro-obovoid, slightly compressed, 2.6–3.8 mm, ribs 7–10 (tan to stramineous), faces sparsely strigillose; pappi of reddish to cream-colored (fine, barbellulate, sometimes apically ± clavate) bristles 3.7–5 mm, equaling or longer than disc corollas. |
straw-colored, ellipsoid to obovoid, 2–3.5 mm, ribs 11–13 prominent, glabrous; pappi of (ca. 35) orangish tan (coarse, sometimes clavellate) bristles 7.8–8.2 mm, slightly longer than disc corollas. |
2n | = 18. |
|
Eurybia divaricata |
Eurybia eryngiifolia |
|
Phenology | Flowering late summer–fall. | Flowering late spring–midsummer. |
Habitat | Dry to mesic, eastern deciduous and mixed deciduous woods, edges and clearings, roadsides | Low pine flatwoods, pine savannas, bogs, often on wet sand, on southern coastal plains |
Elevation | 0–1200(–1700) m (0–3900(–5600) ft) | 0–100 m (0–300 ft) |
Distribution |
AL; CT; DC; DE; GA; KY; MA; MD; ME; MI; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; ON; QC [Introduced in Europe (Netherlands)]
|
AL; FL; GA
|
Discussion | Eurybia divaricata is a mainly Appalachian element of the eastern North American deciduous forest. It is often confused with Eurybia chlorolepis (see W. F. Lamboy 1992 for distinction between the two species), E. schreberi, or Symphyotrichum cordifolium. Lamboy provided a map of the species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eurybia eryngiifolia is known from the Florida panhandle and adjacent areas of southern Georgia and Alabama. The species is of conservation concern in Alabama. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 374. | FNA vol. 20, p. 381. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Aster divaricatus, Aster boykinii, Aster castaneus, Aster corymbosus, Aster corymbosus var. alatus, Aster excavatus, Aster flexilis, Aster stilettiformis, Aster tenebrosus, Biotia corymbosa, Biotia corymbosa var. alata, Biotia macrophylla var. divaricata, E. corymbosa | Aster eryngiifolius, Heleastrum chapmanii, Prionopsis chapmanii |
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 259. (1995) | (Torrey & A. Gray) G. L. Nesom: Phytologia 77: 259. (1995) |
Web links |