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western aster, western mountain aster

aster ponceau, purple-stem American-aster, purple-stem aster, purplestem or swamp or red-stem aster, swamp aster

Habit Perennials, 20–80 cm, colonial; long-rhizomatous. Perennials (7–)100–250(–300) cm, cespitose; thickly short-rhizomatous or with stout, branched caudices, sometimes long-rhizomatous.
Stems

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

1–5+, erect (straight to distally flexuous, stout 5–11 mm diam., usually reddish purple), usually densely to sparsely hirsute or hispid, glabrescent, often proximally glabrate, sometimes glabrate.

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.

(dark green, not crowded) thin, margins remotely serrate to sometimes entire, scabrous, apices acute or acuminate to subcaudate, mucronate, abaxial faces glabrate, ± densely pilose along midveins, adaxial glabrate to scabrous;

basal withering by flowering, subpetiolate to petiolate (petioles ± winged, bases dilated, sheathing), blades spatulate to oblanceolate or lanceolate, 30–10+ × 3–20+ mm, bases attenuate to cuneate, margins remotely crenate-serrate to denticulate or entire, apices acute or acuminate to rounded;

proximal cauline withering by flowering, petiolate to subpetiolate (petioles widely winged, bases auriculate, clasping), blades lanceolate or oblanceolate to oblong, elliptic or elliptic-oblong, (55–)70–200(–220) × 10–40 mm, usually progressively lengthened to mid, bases ± attenuate to cuneate or auriculate and clasping;

distal sessile, blades oblanceolate or lanceolate to oblong or elliptic-oblong (sometimes nearly panduriform), 8–160 × 1–40 mm, progressively reduced distally, strongly so and linear in arrays, bases ± strongly auriculate, clasping, margins subentire or entire.

Peduncles

sparsely hairy, bracts 0–3+.

0.2–3+ cm, ± hispid or hirsute to villous, bracts 0–3, lanceolate or linear-lanceolate to linear, distal often subtending heads.

Involucres

campanulate, 5–10 mm.

campanulate, (6–)8–12(–15) mm.

Ray florets

15–40;

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

20–50(–60);

corollas usually pale to dark blue, lavender or purple, seldom white or pink, laminae (7–)12–18(–21) × (0.9–)1.4–1.8 mm.

Disc florets

30-80(–100);

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

30–50 (–90);

corollas yellow or cream becoming pink or purple, (4.1–)5–6.5 mm, tubes shorter than cylindro-funnelform limbs, lobes triangular, 0.4–1.1 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 4–6 series, oblanceolate-spatulate to linear, subequal, bases indurate 1/5–1/2, margins not scarious (outer) to narrowly scarious, erose, hyaline, sparsely ciliolate, green zones linear-lanceolate, outer sometimes ± foliaceous, to linear (inner), apices ± spreading at tip when foliaceous, long-acuminate to caudate, mucronate to apiculate, sometimes purplish tinged, faces glabrous or ± hispid.

Heads

in corymbiform to paniculiform arrays, branches usually few.

in open, paniculiform (often corymbiform-looking) arrays, branches widely spreading to ascending, sparsely to moderately leafy with ± large leaves.

Cypselae

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

pappi whitish, 5–7 mm.

purple or brown (nerves stramineous), oblanceoloid, ± falcate, compressed, (2–)2.5–3.5(–4) mm, 3–4-nerved (nerves prominent), faces glabrous or sparsely strigillose;

pappi white, 3.8–6 mm.

Symphyotrichum spathulatum

Symphyotrichum puniceum

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; CT; DE; GA; IA; IL; IN; LA; MD; ME; MI; MN; MO; MS; NC; ND; NE; NH; NJ; NY; OH; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; AB; BC; MB; NB; NS; ON; PE; QC; SK
[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.)

Varieties 2 (2 in the flora).

Symphyotrichum puniceum is one of the widest ranging species in the genus, growing from the edges of the prairies to the Atlantic coast, and from the Gulf coast of Texas to southern Ungava Bay (northern Quebec).

Several taxa have been recognized within this variable species. Here, we segregate Symphyotrichum firmum as a distinct entity. The tall, pink-rayed S. elliottii of the outer coastal plains is also distinctive, despite reports of hybrids with S. puniceum var. puniceum where their ranges overlap (see G. L. Nesom 1997b). A recently described member of the complex, S. rhiannon, is an ultramafic endemic from North Carolina. Here, within S. puniceum, we recognize two varieties, the variable and widespread var. puniceum, and var. scabricaule from the inner Gulf coastal plains, following Nesom, who also offered a useful summary of the infraspecific taxonomy of the species.

(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
1. Stems sparsely to ± densely hirsute, glabrescent, sometimes glabrate proximally; abaxial leaf faces paler than adaxial, with a dark, distinct reticulum, adaxial without impressed main veins; array leaves usually equal to mid cauline
var. puniceum
1. Stems densely and uniformly hirsute; abaxial and adaxial leaf faces ±concolorous, without dark, distinct reticulum, adaxial with distinctly impressed main veins; array leaves reduced in size relative to mid cauline
var. scabricaule
Source FNA vol. 20, p. 534. FNA vol. 20, p. 524.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum
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. 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. 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
S. puniceum var. puniceum, S. puniceum var. scabricaule
Synonyms Aster spathulatus Aster puniceus
Name authority (Lindley) G. L. Nesom: Phytologia 77: 291. (1995) (Linnaeus) Á. Löve & D. Löve: Taxon 31: 359. (1982)
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