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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

meadow aster, western meadow aster

Habit Perennials cespitose, (5–)20–120(–150+) cm; with stout, branched caudices, sometimes long-rhizomatous. Perennials, 10–40 cm, colonial or cespitose; long-rhizomatous.
Stems

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

1–5+, ascending to erect (light to dark brown), proximally glabrous, distally strigose, stipitate-glandular.

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 green) firm, margins entire, scabrous;

basal sometimes persistent, sessile, blades (1–3-nerved) linear-oblanceolate, 10–30 × 4–10 mm, bases attenuate, apices obtuse, mucronate, faces glabrate to sparsely scabrous;

proximal cauline withering by flowering, sessile, blades (3-nerved) narrowly oblanceolate, 20–80 × 2–8 mm, bases cuneate, apices obtuse to acute, mucronulate or white-spinulose, faces glabrous or moderately short-strigose, stipitate-glandular;

distal sessile, blades linear-oblanceolate to -lanceolate or oblong (distally), 20–50 × 2–5 mm, ± reduced distally, bases ± clasping to cuneate, apices acute, mucronulate, faces glabrous or moderately short-strigose, 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.

sparsely to moderately short-strigose, moderately stipitate-glandular, bracts ± ascending, linear to narrowly-lanceolate.

Involucres

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

campanulate to cylindro-campanulate, 5.5–8 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.

15–31;

corollas violet, laminae (5–)6–15 × 1–2 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.

25–40;

corollas yellow, 4.5–6 mm, lobes triangular, 0.4–0.8 mm.

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 3–4 series, linear to lanceolate, subequal to unequal, bases ± indurate, margins scarious, green zones covering distal portion, apices acute to acuminate, outer ± foliaceous, spreading to reflexed, faces glabrate, sparsely to densely stipitate-glandular.

Heads

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

1–10(–30), borne singly or in paniculiform arrays, branches ascending.

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.

light brown, sometimes translucent reddish brown between ribs, narrowly obovoid, ± compressed, 2–2.5 mm, 3–4-nerved (faint), moderately strigose on ribs;

pappi tawny, 3.8–6 mm.

2n

= 10.

Symphyotrichum pilosum

Symphyotrichum campestre

Phenology Flowering Aug–Oct.
Habitat Open, often dry, disturbed, rocky and sandy soils near ponds and streams, dry grass meadows, open pine-douglas fir forests, plains to montane zones
Elevation 1500–2500 m (4900–8200 ft)
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
CA; CO; ID; MT; NV; OR; WA; WY; AB; BC
[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.)

Two poorly defined varieties of Symphyotrichum campestre have been described. Variety campestre has glabrous or sparsely strigose leaves and occurs in southern British Columbia, Colorado, Idaho, Montana, Nevada, Oregon, Washington, and Wyoming. Bloomer’s Aster, var. bloomeri, has moderately strigose leaves and occurs in California, Nevada, and Oregon. The varieties are not sufficiently distinct to warrant recognition. Symphyotrichum ×columbianum (Piper) G. L. Nesom (syn. Aster columbianus Piper, A. multiflorus Aiton var. columbianus (Piper) S. F. Blake, Virgulus ×columbianus (Piper) Reveal & Keener) is the hybrid between S. campestre and S. ericoides subsp. pansum.

(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
Source FNA vol. 20, p. 511. FNA vol. 20, p. 484.
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. 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. 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
Synonyms Aster pilosus, Aster ericoides var. pilosus Aster campestris, Aster bloomeri, Aster campestris var. bloomeri, S. campestre var. bloomeri, Virgulus campestris
Name authority (Willdenow) G. L. Nesom: Phytologia 77: 289. (1995) (Nuttall) G. L. Nesom: Phytologia 77: 276. (1995)
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