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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

late purple American-aster, late purple aster, late purple or spreading aster

Habit Perennials cespitose, (5–)20–120(–150+) cm; with stout, branched caudices, sometimes long-rhizomatous. Perennials, 10–100(–120) cm, cespitose; with short, thick, woody caudices, tangled or sometimes cormoid, and long rhizomes.
Stems

1–5+, ascending to erect (straight, stout), glabrate to hirsuto-hispid or pilose, sometimes glabrous or hairy in lines (var. pringlei).

1–5+, ascending to erect (often stout, light to dark brown), sparsely to densely scabroso-hirsute to cinereo-puberulent, or villous distally.

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.

(light to dark green) thick and often stiff (margins flat, sometimes undulate), scabrous;

basal early deciduous, subpetiolate (petioles winged, sheathing), blades spatulate to obovate, 30–70 × 10–30 mm, bases cuneate, margins entire to ± serrulate, scabrous, apices acute to rounded, faces scabroso-hirsute;

proximal cauline sessile, blades usually ovate to lanceolate, rarely spatulate, (20–)30–70(–100) × 10–30(–40) mm, reduced distally, bases strongly cordate-clasping to auriculate-amplexicaul (broadened below constriction), apices acute, faces (grayish green) rugulose, hairy (abaxial inconspicuously veined, adaxial reticulately veined, hairier along veins);

distal sessile, blades narrowly to broadly ovate, 15–35 × 4–13 mm, much reduced on branches, bases strongly cordate-clasping to auriculate-amplexicaul, apices usually acute, sometimes obtuse, mucronate to white-spinulose, faces scabrous, sometimes sparsely to moderately stipitate-glandular.

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.

stiffly ascending, slender, 2–10(–15) cm, scabroso-hirsute to cinereo-puberulent, bracts appressed to spreading, linear, 1–5 mm, grading into phyllaries.

Involucres

campanulate to cylindro-campanulate, (2.5–)3.5–5.1(–6.5) mm.

campanulate, 5.5–12 mm.

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.

12–24+;

corollas light lavender-violet to mauve, rarely white to pinkish, laminae 10–18(–20) × 1–3 mm.

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.

20–50;

corollas yellow, cream, or white turning purple, (4.5–)5.5–7.5 mm, tubes shorter than narrowly funnelform throats, lobes triangular, 0.5–1 mm (glabrous or lobes thinly puberulent).

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 4–7(–8) series, appressed or often slightly recurved-spreading or squarrose, ovate-lanceolate to linear, strongly unequal, bases (tan) ± indurate in proximal 1/3–1/2, margins hyaline, erose, distally scabroso-ciliolate to ciliolate, green zones diamond-shaped, in distal 1/5–1/3, apices (outer) obtuse to acute, appressed to squarrose, (inner) acuminate, often purplish red, faces strigillose or cinereo-puberulent abaxially and near tip adaxially, sometimes moderately stipitate-glandular distally.

Heads

in open, leafy, often pyramidal, paniculiform arrays, branches divaricate or branches 10 cm or less ascending, often arched and secund, sometimes racemiform.

in paniculiform arrays, branches divaricate (heads 1–5+ per branch), terminal shoot often not flowering.

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 brown, obovoid to oblong-obovoid, not compressed, 2–3.5 mm, 7–10-nerved (faint), faces sericeous or strigillose;

pappi tawny, sometimes rose-tinged, 4.5–6.5 mm.

Symphyotrichum pilosum

Symphyotrichum patens

Distribution
from FNA
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
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; FL; GA; IL; IN; KS; KY; LA; MA; MD; ME; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; WV
[WildflowerSearch map]
[BONAP county map]
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.)

Varieties 3 (3 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Stems sparsely to densely hirsute; leaves pilose; various substrates
var. pilosum
1. Stems glabrous; leaves glabrous or glabrate; mainly on calcareous substrates
var. pringlei
1. Involucres turbinate, 8–12 mm; phyllaries in 5–7 series, appressed, obtuse, densely strigillose to canescent, eglandular or sparsely glandular; mostly w of Mississippi River, Interior Uplands of e United States
var. patentissimum
1. Involucres campanulate, 5.5–7.5 mm; phyllaries in 4–5 series, squarrose, acute to acuminate, sparsely to densely strigillose, sparsely to densely stipitate-glandular
→ 2
2. Plants slender; involucres 5.5–6.5 mm; mid phyllaries 0.7–1 mm, faces densely strigillose, sparsely stipitate-glandular; Alabama to Texas, n to Kansas
var. gracile
2. Plants robust; involucres 6–7.5 mm; mid phyllaries 1–1.2 mm, faces densely glandular and sparsely strigillose; mostly e of Mississippi River
var. patens
Source FNA vol. 20, p. 511. FNA vol. 20, p. 488.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus
Sibling taxa
S. adnatum, S. anomalum, S. anticostense, S. ascendens, S. boreale, S. bracteolatum, S. campestre, S. chapmanii, S. chilense, S. ciliatum, S. ciliolatum, S. concolor, S. cordifolium, S. cusickii, S. defoliatum, S. depauperatum, S. drummondii, S. dumosum, S. elliottii, S. ericoides, S. eulae, S. falcatum, S. fendleri, S. firmum, S. foliaceum, S. fontinale, S. frondosum, S. georgianum, S. grandiflorum, S. greatae, S. hallii, S. hendersonii, S. jessicae, S. laeve, S. lanceolatum, S. lateriflorum, S. laurentianum, S. lentum, S. molle, S. nahanniense, S. novae-angliae, S. novi-belgii, S. oblongifolium, S. ontarionis, S. oolentangiense, S. parviceps, S. patens, S. phlogifolium, S. plumosum, S. porteri, S. potosinum, S. praealtum, S. pratense, S. prenanthoides, S. priceae, S. puniceum, S. pygmaeum, S. racemosum, S. retroflexum, S. rhiannon, S. robynsianum, S. sericeum, S. shortii, S. simmondsii, S. spathulatum, S. subspicatum, S. subulatum, S. tenuifolium, S. tradescantii, S. turbinellum, S. undulatum, S. urophyllum, S. walteri, S. welshii, S. yukonense, S. ×amethystinum
S. adnatum, S. anomalum, S. anticostense, S. ascendens, S. boreale, S. bracteolatum, S. campestre, S. chapmanii, S. chilense, S. ciliatum, S. ciliolatum, S. concolor, S. cordifolium, S. cusickii, S. defoliatum, S. depauperatum, S. drummondii, S. dumosum, S. elliottii, S. ericoides, S. eulae, S. falcatum, S. fendleri, S. firmum, S. foliaceum, S. fontinale, S. frondosum, S. georgianum, S. grandiflorum, S. greatae, S. hallii, S. hendersonii, S. jessicae, S. laeve, S. lanceolatum, S. lateriflorum, S. laurentianum, S. lentum, S. molle, S. nahanniense, S. novae-angliae, S. novi-belgii, S. oblongifolium, S. ontarionis, S. oolentangiense, S. parviceps, S. phlogifolium, S. pilosum, S. plumosum, S. porteri, S. potosinum, S. praealtum, S. pratense, S. prenanthoides, S. priceae, S. puniceum, S. pygmaeum, S. racemosum, S. retroflexum, S. rhiannon, S. robynsianum, S. sericeum, S. shortii, S. simmondsii, S. spathulatum, S. subspicatum, S. subulatum, S. tenuifolium, S. tradescantii, S. turbinellum, S. undulatum, S. urophyllum, S. walteri, S. welshii, S. yukonense, S. ×amethystinum
Subordinate taxa
S. pilosum var. pilosum, S. pilosum var. pringlei
S. patens var. gracile, S. patens var. patens, S. patens var. patentissimum
Synonyms Aster pilosus, Aster ericoides var. pilosus Aster patens, Virgulus patens
Name authority (Willdenow) G. L. Nesom: Phytologia 77: 289. (1995) (Aiton) G. L. Nesom: Phytologia 77: 288. (1995)
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