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willow aster, willow-leaf American-aster, willowleaf aster

aster latériflore, calico American-aster, calico aster, calico or one-side or white woodland or starved aster

Habit Perennials (10–)50–150(–200) cm, colonial; fleshy long-rhizomatous. Perennials, 20–120(–150) cm, cespitose; with short, woody, branched caudices, or short-rhizomatous.
Stems

1, erect to ascending (stout, ± glaucous or reddish), glabrate to moderately hispidulous-hirsute (mostly in lines) distally.

1–5+, ascending to erect (± arching, slender, brittle), ± densely pilose or villous to glabrate or glabrous (particularly proximally).

Leaves

thick, firm, margins often revolute, scabrous, apices mucronate, abaxial faces glabrous, vein areoles conspicuous, ± isodiametric, adaxial waxy, glabrate to strigose, ± scabrous (distal cauline with axillary leaf clusters, sometimes becoming branches);

basal withering by flowering, petiolate to subpetiolate (petioles winged, bases sheathing, ciliate), blades spatulate, 40–70 × 10–25 mm, bases attenuate, margins entire to shallowly serrate, apices rounded to obtuse;

proximal cauline withering by flowering, sessile (subpetiolate), blades elliptic or lanceolate to oblanceolate or linear-lanceolate, 40–100(–150) × 3–18 mm, progressively reduced distally, bases cuneate, often slightly rounded, apices acute to attenuate, callus-pointed, abaxial faces scabrellous, adaxial glabrous or ± puberulent;

distal sessile, blades ovate or elliptic-lanceolate to lanceolate or linear, 10–85 × 2–17 mm, progressively reduced distally, bases cuneate, margins entire, apices acute or obtuse, callus-pointed.

thin, membranous, margins serrate to serrulate, scabridulous, apices acute to acuminate, sometimes caudate, mucronulate, abaxial faces glabrous, midveins usually ± densely pilose to glabrate, rarely glabrous, adaxial scabrous (short-strigose) to glabrate;

basal usually withering by flowering, sometimes persisting (new vernal rosettes often developing at flowering), petiolate to subpetiolate (petioles narrowly to ± broadly winged, ciliate, bases ± sheathing), blades oblanceolate, lance-ovate or ovate to spatulate or suborbiculate, 5–35 × 7–25 mm, abruptly attenuate, margins crenate-serrate, apices obtuse to rounded or acute;

proximal cauline mostly withering by flowering, sessile or subpetiolate (petioles broadly winged), blades usually ovate or elliptic to elliptic-oblanceolate or lanceolate, rarely linear-lanceolate, (30–)50–100(–150) × (2–)10–20(–35) mm, greatly reduced distally, bases attenuate to cuneate;

distal sessile, blades ovate, lance-ovate, lance-elliptic, or oblanceolate to lance-linear or linear, 10–150 × 1–30 mm, progressively reduced distally, branch leaves abruptly smaller, bases cuneate, margins sometimes entire.

Peduncles

0.3–2 cm, ± pilose, bracts 5–12+, ascending or recurved-spreading, lance-elliptic to lanceolate or linear-lanceolate, foliaceous, distal closely subtending heads, not grading into phyllaries.

Involucres

campanulate, (4–)5–7(–8) mm.

cylindro-campanulate, (3.5–)4–6(–7) mm.

Ray florets

(6–)20–35;

corollas pale blue-violet to lavender or rose-purple, rarely white, laminae 5–10(–12) × 1–1.7 mm.

8–15(–23);

corollas white, rarely pinkish or purplish, laminae (3–)4–5(–8) × 0.9–1.2 mm.

Disc florets

20–30(–35+);

corollas cream or light yellow turning pinkish purple, 4–6.5 mm, tubes shorter than narrowly funnelform throats, lobes lanceolate, 0.5–1.3 mm.

8–16(–20);

corollas cream to light yellow turning pink or reddish purple, (2.5–)3–5 mm, tubes shorter than funnelform-campanulate throats, lobes strongly reflexed, lanceolate, 0.9–1.7 mm.

Phyllaries

in 4–6 series, appressed, oblong-lanceolate to linear (innermost) (outer sometimes ± foliaceous), unequal, bases indurate 1/2–3/4, margins scarious, erose, hyaline, sparsely ciliolate (often ciliate basally), green zones lanceolate to lance-rhombic, apices sometimes spreading, acute to acuminate, mucronate, often reddish purple apically, faces glabrous.

in 3–4(–6) series, appressed or slightly spreading, oblong-lanceolate or -oblanceoalte (outer) to linear (inner), unequal, bases indurate 1/3–2/3, margins scarious, erose, hyaline or sometimes reddish, ± ciliolate, green zones lanceolate to ± diamond-shaped, apices (outer) acute, callus-pointed, (mid) acute to acuminate, or obtuse, sometimes purplish, abaxial faces glabrous (outer), mid sparsely puberulent.

Heads

in ample, foliaceous, usually dense, paniculiform arrays, branches ascending to spreading, ± racemiform.

in ample, open, diffuse, ± pyramidal, paniculiform arrays, branches divaricate to long-arching or ± ascending, slender, wiry, secund; usually sessile, sometimes peduncles 0.1–1 cm+, ± pilose, bracts 1–7, linear or subulate to oblong-lanceolate, foliaceous, grading into phyllaries.

Cypselae

purple or stramineous with purple, obovoid, sometimes ± compressed, 1.5–2 mm, 4–5-nerved, faces thinly strigillose;

pappi white, 4–6.5 mm.

gray or tan, oblong-obovoid, sometimes ± compressed, (1.3–)1.8–2.2 mm, 3–5-nerved, faces sparsely strigillose;

pappi white to pinkish, 3–4 mm.

2n

= 32, 48, 64.

= 16, 32, 48.

Symphyotrichum praealtum

Symphyotrichum lateriflorum

Phenology Flowering Aug–Oct. Flowering Aug–Oct.
Habitat Wet, loamy soils, wet prairies or meadows, lake and stream shores, oak savannas, open woods or thickets, fields, moist banks, ditches, roadsides, recent clearings Relatively shaded habitats, dry to humid soils, usually deciduous woodlands (beech–maple, oak–hickory, mixed hardwoods), sometimes conifer woods, sometimes swamp forests (conifer or dediduous), edges of woods, meadows, usually rocky or sandy stream and pond shores, roadsides
Elevation 0–400+ m (0–1300+ ft) 0–400 m (0–1300 ft)
Distribution
from FNA
AL; AR; CT; DC; DE; FL; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MO; MS; NE; NH; NJ; NY; OH; OK; PA; RI; SD; TN; TX; VA; WI; WV; ON; Mexico (Chihuahua, Coahuila, Nuevo Léon) [Introduced in Europe]
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; MB; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Symphyotrichum praealtum was reported by H. R. Hinds (2000) as a possible introduced, non-persisting ephemeral in New Brunswick. The species is introduced in central Europe, where it has been confused with S. lanceolatum (J. C. Semple et al. 2002). A. G. Jones (1989) reported hybridization with S. lanceolatum and S. firmum.

G. L. Nesom (1994b, 1997) and J. C. Semple et al. (2002) recognize several varieties within the species: var. praealtum [syn. Aster coerulescens de Candolle, A. praealtus var. coerulescens (de Candolle) A. G. Jones, A. praealtus var. imbricatior Wiegand] (2n = 32); var. angustior (Wiegand) G. L. Nesom (syn. A. praealtus var. angustior Wiegand) (2n = 64); var. nebraskense (Britton) G. L. Nesom (syn. A. praealtus var. nebraskensis Britton); var. subasperum (Lindley) G. L. Nesom [syn. A. praealtus var. subasper (Lindley) Wiegand, A. subasper Lindley]; and var. texicola (Wiegand) G. L. Nesom (syn. A. praealtus var. texicola Wiegand). Some of these varieties deserve recognition, but the validity of others needs confirmation.

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

Symphyotrichum lateriflorum has been reported in British Columbia as an ephemeral that did not persist. G. L. Nesom (1994b) and J. C. Semple et al. (2002) recognized several varieties within the complex: var. lateriflorum (syn. Aster vimineus Lamarck); var. angustifolium (Wiegand) G. L. Nesom (syn. A. lateriflorus var. angustifolius Wiegand); var. flagellare (Shinners) G. L. Nesom (syn. A. lateriflorus var. flagellaris Shinners, A. lateriflorus var. indutus Shinners); var. hirsuticaule (Lindley ex de Candolle) G. L. Nesom [syn. A. hirsuticaulis Lindley ex de Candolle, A. lateriflorus var. hirsuticaulis (Lindley ex de Candolle) Porter]; var. horizontale (Desfontaines) G. L. Nesom [syn. A. horizontalis Desfontaines, A. lateriflorus var. horizontalis (Desfontaines) Farwell]; var. spatelliforme (E. S. Burgess) G. L. Nesom [syn. A. spatelliformis E. S. Burgess, A. lateriflorus var. spatelliformis (E. S. Burgess) A. G. Jones]; and var. tenuipes (Wiegand) G. L. Nesom (syn. A. lateriflorus var. tenuipes Wiegand, A. acadiensis Shinners). Much genetic and phenotypic variation is encountered within the complex; a thorough study is needed before a coherent taxonomy can be achieved.

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

Source FNA vol. 20, p. 521. FNA vol. 20, p. 517.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum 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. 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. 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
Synonyms Aster praealtus, Aster salicifolius Solidago lateriflora, Aster lateriflorus
Name authority (Poiret) G. L. Nesom: Phytologia 77: 289. (1995) (Linnaeus) Á. Löve & D. Löve: Taxon 31: 359. (1982)
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