Symphyotrichum laeve |
Symphyotrichum pygmaeum |
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aster lisse, Geyer's aster, smooth American-aster, smooth aster, smooth blue aster |
pygmy aster |
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Habit | Perennials (15–)20–70(–120) cm, cespitose; stoutly short-rhizomatous, with thick, woody caudices or a few, long rhizomes. | Perennials 1.5–15 cm, cespitose; with short, branched caudices, long-rhizomatous (both wiry). | ||||||||||||
Stems | 1–5+, erect (straight, glaucous, sometimes reddish proximally), glabrous, sometimes sparsely hirsute distally. |
1–10+, decumbent to ascending (purple), sparsely or densely villous to woolly distally. |
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Leaves | (glaucous) thick, firm, ± fleshy, margins crenate-serrate or -serrulate or entire, scabridulous, apices mucronulate, faces glabrous; basal usually withering by flowering or sometimes persistent (var. purpuratum), petiolate (petioles ± winged, bases dilated, sheathing), blades spatulate or oblong to ovate or lanceolate-ovate, 30–200 × 10–25(–30) mm, bases attenuate or cuneate to rounded, margins crenate-serrate to serrulate, apices acute to obtuse or rounded; proximal cauline often withering by flowering, petiolate or subsessile or sessile (petioles narrowly to broadly winged, clasping), blades ovate or oblong-ovate to lanceolate or linear-lanceolate, sometimes ± panduriform, (40–)80–150(–180) × (10–)20–45 mm, bases attenuate to rounded or ± shallowly auriculate-clasping, margins entire or shallowly crenate-serrate, minutely scabrous, apices acute or obtuse, callus-pointed; distal sessile, blades lance-ovate or lanceolate to linear, 7–45 × 1–14 mm, progressively reduced distally (abruptly so in arrays), bases auriculate and ± clasping to rounded, margins entire. |
firm, margins usually entire, sometimes remotely pauci-serrulate, sparsely villoso-ciliate, apices obtuse to acute, sometimes mucronate; basal often withering by flowering, petiolate (petioles widely winged, sheathing), blades spatulate, 5–19 × 2–4 mm, bases attenuate, apices rounded, faces glabrous or sparsely villous proximally; proximal sessile, blades lanceolate to oblong-lanceolate or (sometimes) -spatulate, 30–50 × 3–10 mm, bases ± clasping, apices obtuse to acute, faces glabrous or sparsely villous; distal sessile, blades lanceolate to oblong, 13–19 × 2–4.5 mm, bases clasping to cuneate, apices acute to obtuse, faces sparsely woolly, sometimes sparsely stipitate-glandular. |
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Peduncles | 0.2–6+ cm, glaucous, glabrous or puberulent in lines, bracts 3–6, densely spaced, subulate or linear-lanceolate to linear, subclasping, apices sometimes purplish, grading into phyllaries. |
densely villous to lanate distally, bracts 0. |
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Involucres | campanulate to cylindro-campanulate, (4.2–)5–7(–8) mm. |
hemispherico-campanulate, 9–12.5 mm. |
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Ray florets | (11–)13–23(–34); corollas usually pale to dark blue or purple, seldom white, laminae (6–)7.2–11.3(–14.6) × 1.5–2.5 mm. |
16–28; corollas purple to violet, laminae 12–18 × 2–3.2 mm. |
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Disc florets | (17–)19–33(–43); corollas yellow turning purplish red, 3.5–6.1 mm, tubes slightly shorter than funnelform throats, lobes triangular, (0.4–)0.6–1 mm. |
53–55; corollas yellow, 5.6–6.5 mm, throats funnelform, lobes triangular, 0.5–0.8 mm (red or white clavate-hairy). |
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Phyllaries | in 4–6 series, appressed, subulate or lanceolate (outer) to oblong-lanceolate or linear-lancolate or -oblanceolate, unequal (sometimes appearing subequal), bases indurate 1/2–3/4, margins scarious, erose, hyaline, ciliolate distally, green zones mostly diamond-shaped to ± lanceolate (some inner, or most in var. geyeri), apices acute to acuminate, sometimes ± obtuse, red-mucronate or apiculate, faces glabrous. |
in 3–4 series (dark purple), lance-oblong or oblong (outer) to linear-lanceolate or sometimes linear (inner), subequal, outer ± herbaceous, bases not indurate, margins herbaceous (outer) to narrowly scarious and erose proximally (inner), strongly purple, villoso-ciliate in green portion, green zones (inner) 1/2–2/3 of distal portions, apices acute to acuminate, inner sometimes apiculate, appressed to loose and squarrose (particularly outer), faces woolly to densely villous, sparsely to moderately stipitate-glandular. |
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Heads | in broad, sometimes ± flat-topped, paniculiform arrays, branches stiffly ascending (rarely arching), leafy with small, gradually reduced branch leaves. |
borne singly. |
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Cypselae | deep purple to brown, oblong-obovoid, compressed, 2–3.5 mm, 4–5-nerved, faces glabrous or glabrate; pappi tawny to red- or rose-tinged, 5–7 mm. |
fusiform to cylindro-obconic, ± compressed, [size unknown], 4–7-nerved (faint), faces ± densely strigillose; pappi whitish to yellowish, 5–7.2 mm. |
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Symphyotrichum laeve |
Symphyotrichum pygmaeum |
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Phenology | Flowering summer. | |||||||||||||
Habitat | Open, active, moist sand dunes, sandy or silty stream banks and terraces, usually cyclically disturbed gravelly tundra and tundra slopes | |||||||||||||
Elevation | 0–200+ m (0–700+ ft) | |||||||||||||
Distribution |
AL; AR; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; ON; QC; SK; YT; ne Mexico [Introduced in other areas of Mexico, Central America, Europe]
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AK; NT; NU |
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Discussion | Varieties 4 (4 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Symphyotrichum pygmaeum has long been included within or associated with Eurybia sibirica. Though similar in appearance, the two species can be distinguished by the glands present on S. pygmaeum on the distal leaves and phyllaries. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 508. | FNA vol. 20, p. 485. | ||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus | ||||||||||||
Sibling taxa | ||||||||||||||
Subordinate taxa | ||||||||||||||
Synonyms | Aster laevis | Aster pygmaeus, Aster sibiricus subsp. pygmaeus, Aster sibiricus var. pygmaeus, Eurybia pygmaea | ||||||||||||
Name authority | (Linnaeus) Á. Löve & D. Löve: Taxon 31: 359. (1982) | (Lindley) Brouillet & S. Selliah: Sida 21: 1635. (2005) | ||||||||||||
Web links |
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