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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

amethyst aster, aster, hybrid aster

Habit Perennials 10–60 cm, colonial; long-rhizomatous. Perennials, cespitose, 30–120 cm; with thick, woody, short-branched caudices at ends of fleshy rhizomes.
Stems

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

1–5+, erect (light brown to grayish brown), densely hispidulo-hirsute.

Leaves

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.

light green, thin to firm;

basal withering by flowering, sessile, blades oblanceolate, 10–40 × 3–10 mm, attenuate, margins usually entire, rarely remotely serrate, piloso-ciliate, apices obtuse, rounded to mucronulate, faces sparsely to moderately strigose;

proximal cauline sometimes persistent by flowering, sessile, blades linear or oblong to elliptic-oblanceolate, 40–60 × 3–10 mm, bases rounded or slightly clasping, margins entire, scabrous, apices acute to obtuse, faces ± copiously hirsute;

distal sessile, blades oblanceolate, 15–45 × 2–3(–4.5) mm, progressively reduced distally, bases cuneate, margins entire, apices acute, white-spine-tipped, faces sparsely strigose.

Peduncles

sparsely hairy, bracts 0–3, lanceolate.

hispid, bracts 1–3+, oblong-lanceolate, 3–5 mm, not grading into phyllaries.

Involucres

campanulate, 6–16(–20) mm.

campanulate to hemispheric, 4–6 mm.

Ray florets

15–60;

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

20–35;

corollas azure blue to violet or lavender, laminae 5–10 × 0.6–1.2 mm.

Disc florets

50–150;

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

20–30+;

corollas light yellow turning pinkish to purple, 3–4 mm, tubes ca. 1/2 narrowly funnelform throats, lobes triangular, 0.5–0.7 mm, glabrous.

Phyllaries

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.

in 3–5 series, linear-lanceolate, ± unequal to subequal, bases ± indurate, margins hyaline proximally, outer distally hispido-scabrous, green zones diamond-shaped, restricted to distal 1/2–1/4, apices (outer) spreading to reflexed, acute, subspinulose, (inner) acuminate, purplish, faces (outer) scabroso-puberulent or strigose, eglandular, inner distally stipitate-glandular.

Heads

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

in ample, leafy, paniculiform arrays, branches ascending, sometimes secund (heads often crowded).

Cypselae

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

pappi white to tawny, 5–8 mm.

dull purple or brown, obovoid, not compressed, 1.5–2 mm, 7–9-nerved, faces densely sericeous;

pappi tan to tawny, sometimes rose to violet-tinged, 3.5–5.5 mm.

2n

= 10.

Symphyotrichum foliaceum

Symphyotrichum ×amethystinum

Phenology Flowering Aug–Oct.
Habitat Fields, prairies, disturbed grounds
Elevation 200–400 m (700–1300 ft)
Distribution
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; CT; IA; IL; IN; KY; MA; MD; MN; MO; ND; NE; NJ; NY; PA; RI; VT; WA; WI; ON
[BONAP county map]
Discussion

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.)

Symphyotrichum ×amethystinum is the F1 hybrid between S. ericoides and S. novae-angliae, encountered sometimes throughout the area where the two parental species co-occur. It is morphologically intermediate; it has non-spiny, sparsely stipitate-glandular phyllaries and rose-violet rays in mid-sized heads. Forma leucerythros Bemis and forma leucos Bemis have been described within this hybrid and may represent recombinants or normal population color variants.

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

Key
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. 532. FNA vol. 20, p. 497.
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. 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
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. tenuifolium, S. tradescantii, S. turbinellum, S. undulatum, S. urophyllum, S. walteri, S. welshii, S. yukonense
Subordinate taxa
S. foliaceum var. apricum, S. foliaceum var. canbyi, S. foliaceum var. foliaceum, S. foliaceum var. parryi
Synonyms Aster foliaceus Aster amethystinus, Virgulus ×amethystinus
Name authority (Lindley ex de Candolle) G. L. Nesom: Phytologia 77: 282. (1995) (Nuttall) G. L. Nesom: Phytologia 77: 294. (1995)
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