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perennial saltmarsh American-aster, perennial saltmarsh aster

alpine leafybract aster, Canby's leafybract aster, Cusick's American aster, Cusick's aster, Henderson's aster, Kootenai aster, leafy aster, leafy or leafy-bract or alpine leafybract aster, leafy-bract aster, Parry's aster

Habit Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. Perennials 10–60 cm, colonial; long-rhizomatous.
Stems

1–5+, ascending to erect (often with purple or purplish brown areas, flexuous, wiry), little-branched, usually glabrous, sometimes hairy in lines distally.

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

Leaves

thick (fleshy), margins entire, faces glabrous;

basal withering by flowering (new winter rosettes appearing at flowering), petiolate (petioles sheathing), blades ovate or oblanceolate, 15–20 × 5–15 mm, bases cuneate, apices rounded;

proximal cauline withering by flowering, usually sessile, blades lanceolate, linear-lanceolate or -oblanceolate, to linear, 7–80(–150) × 1–6 (–12) mm, bases attenuate, margins entire, apices acuminate to acute;

distal sessile, blades narrowly lanceolate to subulate, 10–110 × 0.5–5 mm, apices acuminate.

thin, margins entire or sometimes serrate, apices acute to obtuse, faces usually glabrous, sometimes sparsely hairy;

basal usually persistent, petiolate to subpetiolate, blades broadly elliptic to obovate, 30–200 × 8–25(–30) mm, bases attenuate, margins entire or sometimes serrate, apices acute to obtuse;

proximal cauline sessile or subpetiolate, blades elliptic to obovate, 35–120 × 8–25 mm, bases attenuate or cuneate to rounded, sometimes ± clasping, apices acute;

distal sessile, reduced distally, bases cuneate, apices acute.

Peduncles

0.6–4 (–6) cm, bracts 2–8, awl-shaped, grading into phyllaries.

sparsely hairy, bracts 0–3, lanceolate.

Involucres

narrowly turbinate, 4.1–9.5(–11) mm.

campanulate, 6–16(–20) mm.

Ray florets

10–25;

corollas white or pink, laminae (4.5–)5–8.5(–9.5) × 1.2–2 mm.

15–60;

corollas violet to purple, laminae 8–18(–20) × 1–2 mm.

Disc florets

25–45(–54);

corollas yellow becoming purplish, 3.4–6(–6.8) mm, tubes shorter than to equaling the narrowly funnelform throats (sparsely hairy at base), lobes ± erect, narrowly triangular, 0.5–0.8 mm.

50–150;

corollas yellow, 4–7 mm, lobes triangular, 0.4–1 mm.

Phyllaries

in 4–5 series, lanceolate to subulate, bases indurate, rounded, margins hyaline, often tinged with purple, entire, green zones spatulate to oblanceolate-rhombic, apices acute, adaxial faces glabrous or minutely hairy distally.

in 4–6 series, oblanceolate or oblong (outer) to lanceolate or linear (inner), subequal or unequal (outer exceeding inner), bases outer foliaceous, inner indurate, margins entire, green zones elliptic to lanceolate, apices acute to rounded, faces glabrous or puberulent.

Heads

(1–)3–20(–40), in open, diffuse, paniculiform arrays, branches patent.

borne singly or in paniculiform arrays, branches ascending, up to 25 cm.

Cypselae

light brown, narrowly obovoid to fusiform, sometimes ± compressed, 1.5–4(–4.5) mm, 5–6-nerved, faces sparsely strigillose;

pappi tawny to white, 3–6.1 mm.

brown, cylindric to obovoid, not compressed, 2.5–4 mm, 3–4-nerved, faces hairy;

pappi white to tawny, 5–8 mm.

Symphyotrichum tenuifolium

Symphyotrichum foliaceum

Distribution
from FNA
AL; CT; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; RI; SC; TX; VA; West Indies
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Along the Gulf of Mexico Coast in central and northern peninsular Florida, vars. tenuifolium and aphyllum intergrade in nearly all characters (S. D. Sundberg 2004). G. L. Nesom (2005d) treated the varieties as species.

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

Varieties 4 (4 in the flora).

Symphyotrichum foliaceum is extremely variable and is widespread in western montane coniferous forests and subalpine meadows.

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

Key
1. Stems 1, rhizomes long; mid leaves (1.5–)3–6 mm wide; involucres 6–9.5(–11) mm; ray florets (12–)17–25; disc florets 25–45(–54), corollas (4–)4.7–6(–6.5) mm; cypselae 2.8–4(–4.5) mm; pappi 5–6.1 mm
var. tenuifolium
1. Stems 1–5+ (clustered), rhizomes short; mid leaves (1–)1.5–2.7 mm wide; involucres 4.1–5.3 mm; ray florets 10–16; disc florets (10–)13–23, corollas 3.4–4.6 mm; cypselae 1.5–2(–2.5) mm; pappi 3–4.4 mm
var. aphyllum
1. Plants 5–30 cm; heads 1–12; phyllaries subequal, narrowly lanceolate
→ 2
1. Plants usually 20–60 cm; heads usually 5–20; outer phyllaries exceeding inner, wider, often foliaceous
→ 3
2. Plants 5–20 cm; heads usually borne singly; phyllaries often purple-tinged; alpine or sub- alpine habitats
var. apricum
2. Plants 10–30 cm; heads usually 1–12; phyllaries green; montane to subalpine habitats.
var. parryi
3. Phyllaries obtuse to rounded; cauline leaves often clasping at base
var. canbyi
3. Phyllaries acute; cauline leaves sometimes rounded at base, not clasping
var. foliaceum
Source FNA vol. 20, p. 479. FNA vol. 20, p. 532.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales
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. spathulatum, S. subspicatum, S. subulatum, 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. 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. tenuifolium var. aphyllum, S. tenuifolium var. tenuifolium
S. foliaceum var. apricum, S. foliaceum var. canbyi, S. foliaceum var. foliaceum, S. foliaceum var. parryi
Synonyms Aster tenuifolius Aster foliaceus
Name authority (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) (Lindley ex de Candolle) G. L. Nesom: Phytologia 77: 282. (1995)
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