Symphyotrichum pilosum |
Symphyotrichum prenanthoides |
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aster poilu, awl American-aster, frost aster, hairy aster, hairy white Oldfield aster, Oldfield or frost weed or white Oldfield or hairy or hairy white Oldfield aster, white heath aster |
crooked-stem American-aster, crookedstem aster |
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Habit | Perennials cespitose, (5–)20–120(–150+) cm; with stout, branched caudices, sometimes long-rhizomatous. | Perennials, 20–90(–120) cm, colonial; long-rhizomatous. | ||||
Stems | 1–5+, ascending to erect (straight, stout), glabrate to hirsuto-hispid or pilose, sometimes glabrous or hairy in lines (var. pringlei). |
1(–3+), ascending to erect (usually flexuous, sometimes ± straight, sometimes stout, older often dark purple), glabrous proximally, moderately hirsute distally. |
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Leaves | thin, margins ciliate, apices acute to acuminate, mucronate, faces glabrous or ± hirsute (particularly on abaxial midveins); basal withering by flowering (new vernal rosettes developing at flowering), petiolate to subpetiolate (petioles winged, ciliate, bases sheathing), blades oblanceolate or obovate to spatulate, 10–60 × 5–15 mm, bases attenuate, margins sparsely crenate-serrate (mostly apically), apices obtuse to rounded; proximal cauline usually deciduous at flowering (often with axillary clusters of small leaves), petiolate or subpetiolate to subsessile (petioles narrowly to broadly winged, clasping), blades elliptic-oblanceolate or -oblong to linear-lanceolate or -oblanceolate, 40–102 × 5–25 mm, progressively reduced distally, bases attenuate to cuneate, ± clasping, margins entire to serrate, softly ciliate, apices attenuate, hyaline-spinulose; distal sessile, blades lance-oblong to linear-lanceolate to linear or linear-oblanceolate or linear-subulate, 10–100 × 1–8 mm, progressively reduced distally, branch leaves abruptly smaller, bases cuneate, margins entire or serrulate. |
thin, margins scabrous, apices mucronate, abaxial faces glabrous, midveins hispid to glabrate, adaxial scabrous; basal withering by flowering, petiolate (petioles slender or slightly winged, bases reddish, dilated, sheathing, ciliate), blades obovate to oblanceolate, 15–70 × 10–20 mm, bases attenuate, margins crenate-serrate, apices acute to obtuse; proximalmost cauline withering by flowering, proximal mostly persistent, petiolate to subpetiolate (petioles ± widely winged, bases dilated, strongly auriculate-clasping), blades ovate to lance-ovate or elliptic-lanceolate to oblanceolate, 80–160(–200) × 15–55 mm, progressively reduced distally, bases attenuate, margins sharply serrate (teeth mucronulate), apices acuminate to subcaudate; distal subpetiolate or sessile (petioles broadly winged, auriculate-clasping), blades oblanceolate to lanceolate, sometimes panduriform, 7–90 × 2–25 mm, progressively reduced distally, more sharply so on branches, bases attenuate (petiolate) or ± cuneate to auriculate-clasping and slightly constricted above auricles (panduriform), margins serrate or entire. |
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Peduncles | 5–30(–50) mm, progressively shorter distally, glabrous or densely hispid, bracts 7–25+, appressed to ascending, sometimes ± spreading, linear to subulate, glabrate, ciliate or not, mucronate to apiculate, ± grading into phyllaries. |
(8–)10–40 mm, sparsely to densely hispid, bracts lanceolate to linear-lanceolate, 3–12 mm, somewhat grading into phyllaries. |
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Involucres | campanulate to cylindro-campanulate, (2.5–)3.5–5.1(–6.5) mm. |
campanulate, 5–6 mm. |
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Ray florets | (10–)16–28(–38); corollas usually white, rarely pinkish or bluish, laminae (4–)5.4–7.5(–11) × (0.4–)0.8–1.3(–1.7) mm. |
17–25(–30); corollas usually lavender to blue, rarely white, laminae 7.5–12(–15) × 1–2 mm. |
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Disc florets | (13–)17–39(–67); corollas light yellow becoming reddish purple or brown, (2.5–)3–4.1(–5.5) mm, tubes much shorter than narrowly funnelform throats, lobes lanceolate, (0.4–)0.6–0.8(–1) mm. |
39–50(–65); corollas cream colored or light yellow becoming purple or brown, 3.5–5 mm, tubes ± equaling campanulate to funnelform throats (thinly puberulent), lobes triangular, 0.5–1 mm. |
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Phyllaries | in 4–6 series, appressed or slightly spreading, oblong-lanceolate (outer) to linear (innermost) , unequal (rarely subequal), bases indurate 1/2–3/5, margins hyaline, scarious, erose, ± ciliolate distally, green zones lanceolate to lance-rhombic, apices acute or acuminate, involute, spinulose, faces glabrous or sparsely hirsutulous. |
in 4–6 series, oblong-lanceolate or -oblanceolate, slightly constricted near middle (outer) to linear-lanceolate or linear (inner), ± unequal (flexible), bases indurate 1/5–1/2, margins ± narrowly hyaline, scarious, erose, sometimes ciliolate distally, green zones lanceolate to linear-lanceolate (inner), often distally foliaceous, sometimes outer ± entirely so, apices spreading to ± squarrose, acute to acuminate, mucronulate, abaxial faces sparsely hirsutulous to glabrate or glabrous, adaxial glabrous or sparsely hirsutulous. |
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Heads | in open, leafy, often pyramidal, paniculiform arrays, branches divaricate or branches 10 cm or less ascending, often arched and secund, sometimes racemiform. |
in broad, ± flat, corymbo-paniculiform arrays, branches often purplish, divaricate to ascending, slender. |
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Cypselae | whitish or gray, oblong-obovoid, sometimes ± compressed, 1–1.5 × 0.5–0.7 mm, 4–6-nerved, faces sparsely strigillose; pappi white, 3.5–4 mm. |
dull purple or stramineous with purple streaks or purplish-tinged, cylindro-oblanceoloid to obovoid, ± compressed, 2–3(–3.5) mm, 4–6-nerved, faces sparsely to moderately strigillose; pappi sordid, 3.5–4.5 mm. |
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2n | = 32. |
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Symphyotrichum pilosum |
Symphyotrichum prenanthoides |
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Phenology | Flowering Aug–Oct. | |||||
Habitat | Moist or swampy grounds, woods, thickets, meadows, seeps, stream banks, roadsides | |||||
Elevation | 100–1500 m (300–4900 ft) | |||||
Distribution |
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; VA; VT; WI; WV; BC; NB; NS; ON; QC
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CT; DC; DE; IA; IL; IN; KY; MA; MD; MI; MN; NC; NJ; NY; OH; PA; VA; WI; WV; ON
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Discussion | Varieties 2 (2 in the flora). The ecology and cytogeography of Symphyotrichum pilosum were summarized by J. G. Chmielewski and J. C. Semple (2001b). The species is often confused with S. ericoides, which inhabits the same kinds of open, prairie-like habitats; the latter can be distinguished by its smaller heads and spine-tipped phyllary apices. Because of that, the name Aster ericoides has been misapplied often in floras and in the horticultural trade. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Symphyotrichum prenanthoides is of conservation concern in Canada and in a number of states. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 511. | FNA vol. 20, p. 527. | ||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Aster pilosus, Aster ericoides var. pilosus | Aster prenanthoides | ||||
Name authority | (Willdenow) G. L. Nesom: Phytologia 77: 289. (1995) | (Muhlenberg ex Willdenow) G. L. Nesom: Phytologia 77: 290. (1995) | ||||
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