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western aster, western mountain aster

aster de nouvelle-angleterre, New England American-aster, New England aster, New England or michaelmas daisy

Habit Perennials, 20–80 cm, colonial; long-rhizomatous. Perennials, 30–120 cm, cespitose; with thick, woody, branched caudices, or short, fleshy rhizomes, sometimes with woody cormoid portions.
Stems

1–5+, ascending to erect, glabrous or sparsely puberulent.

1–5+, erect (stout, light to dark brown, sometimes purplish distally), proximally sparsely to moderately hispiduloso-hirsute or pilose, distally moderately to densely so, stipitate-glandular.

Leaves

thin, margins entire, apices acute, faces glabrous or sparsely puberulent;

basal persistent, petiolate, blades narrowly elliptic to obovate, 50–150 × 3–15 mm, attenuate, margins entire;

proximal cauline sessile or subpetiolate, blades linear to narrowly elliptic, 50–150 × 2–15 mm, bases attenuate or cuneate;

distal sessile, blades 30–60 × 2–10 mm, reduced distally, bases cuneate to rounded.

(light to dark green) thin, often stiff, margins entire or sometimes with shallow teeth, ciliate;

basal withered or withering by flowering, sessile, blades (3-nerved) usually spatulate, sometimes oblanceolate, 20–60 × 5–15 mm, bases attenuate, apices acute, faces sparsely hirsute;

proximal cauline withering by flowering, sessile, blades oblong or lanceolate, 50–100 × 5–15(–20) mm, bases auriculate-clasping, margins entire, pustulate-scabrous, apices acute, mucronulate, faces stipitate-glandular, abaxial thinly strigose, adaxial hirsute or hispidulous;

distal sessile, blades oblanceolate, 30–80 × 6–15 mm, gradually reduced distally, bases auriculate-clasping, apices acute to obtuse, mucronate to minutely white-spinulose, faces moderately to densely short-soft-hairy, sparsely to moderately stipitate-glandular.

Peduncles

sparsely hairy, bracts 0–3+.

dilated distally, 0.3–4 cm, densely short-hairy, stipitate-glandular, bracts 1–4, foliaceous, linear to narrowly lanceolate, densely short-hairy, stipitate-glandular, grading into phyllaries.

Involucres

campanulate, 5–10 mm.

campanulate to hemispheric, (5–)7–9(–15) mm.

Ray florets

15–40;

corollas violet, laminae 9–15 × 1–2 mm.

(40–)50–75(-100);

corollas dark rose to deep purple (pale pink or white), laminae 9–13 × 0.8–1.3 mm.

Disc florets

30-80(–100);

corollas yellow, sometimes becoming reddish, 4.5–6 mm, lobes triangular, 0.5–1 mm.

50–110;

corollas light yellow becoming purple, (4–)4.5–5.5(–7) mm, tubes ± 1/2 narrowly funnelform throats (glabrous or thinly puberulent), lobes triangular, 0.4–0.7 mm.

Phyllaries

in 3–5 series, narrowly oblong or linear (outer) to linear (inner), unequal, bases indurate, margins entire, green zones elliptic to lanceolate, apices usually acute, sometimes obtuse, faces glabrous or ± puberulent.

in 3–5(–6) series (dark green to purple-tinged), linear-lanceolate, subequal, outer foliaceous, mid and inner scarious in basal 1/3–1/2, margins stipitate-glandular, apices long-acuminate to acuminate, spreading to reflexed or squarrose, faces glabrous, outer densely stipitate-glandular.

Heads

in corymbiform to paniculiform arrays, branches usually few.

in leafy, often crowded, paniculo-corymbiform arrays.

Cypselae

brown, cylindric to obovoid, not compressed, 2.5–3.5 mm, ± 4-nerved, faces hairy;

pappi whitish, 5–7 mm.

dull purple or brown, oblong or obconic, not compressed, 1.8–2.5(–3) × 0.6–1 mm, 7–10-nerved, faces densely sericeous, sparsely stipitate-glandular;

pappi tawny (barb tips sometimes rose-tinged), 4.5–6 mm.

2n

= 10.

Symphyotrichum spathulatum

Symphyotrichum novae-angliae

Phenology Flowering Aug–Oct(–Nov).
Habitat Open, moist to wet, sandy or loamy, rich soils, fields, prairies, meadows, marshy grounds, shrubby swamps, fens, shores, thickets, moist edges of woods, roadsides, railroad rights-of-way, somewhat weedy
Elevation 0–1600 m (0–5200 ft)
Distribution
from FNA
CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC; NT; nw Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CO; CT; DC; DE; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; SD; TN; UT; VA; WA; WI; WV; WY; MB; NB; NS; ON; QC [Introduced in Europe]
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

Symphyotrichum spathulatum is a variable species, widespread in montane regions of western North America. It hybridizes with S. bracteolatum, S. foliaceum, and S. hendersonii.

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

Symphyotrichum novae-angliae is escaped from cultivation and introduced in Montana, Oregon, Utah, Washington, and Wyoming, and has been reported as an ephemeral escape in British Columbia. It possibly escaped from cultivation elsewhere. The Michaelmas daisy is widely sold in the horticultural trade, where cultivars have been developed. Forms have been described that correspond to color genetic variants within natural populations {Aster novae-angliae forma roseus (Desfontaines) Britton; A. novae-angliae forma geneseensis House}; they are not recognized here.

Symphyotrichum novae-angliae resembles Canadanthus modestus, but the ranges of the two do not overlap, and the latter has sparsely hairy cypselae with dark ribs. Symphyotrichum novae-angliae hybridizes with S. ericoides, forming the F1 intersectional hybrid S. ×amethystinum.

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

Key
1. Leaves linear
var. yosemitanum
1. Leaves narrowly elliptic to oblanceolate
→ 2
2. Plants 40–80 cm; heads usually 10–50
var. intermedium
2. Plants 20–50(–60) cm; head usually 3–10
var. spathulatum
Source FNA vol. 20, p. 534. FNA vol. 20, p. 487.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales 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. 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. 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. 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. spathulatum var. intermedium, S. spathulatum var. spathulatum, S. spathulatum var. yosemitanum
Synonyms Aster spathulatus Aster novae-angliae, Virgulus novae-angliae
Name authority (Lindley) G. L. Nesom: Phytologia 77: 291. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 287. (1995)
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