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aster lancéolé, lance-leaf American-aster, lance-leaf aster, lance-leaf or panicle or white panicle aster, marsh aster, panicle aster, tall white aster, western willow aster, white-panicle aster

aster cordifolié, common blue wood aster, heart-leaf American-aster, heart-leaf aster, heartleaf or common blue wood aster

Habit Perennials, 30–150(–200) cm, colonial; long-rhizomatous (rhizomes usually white, thick, contorted). Perennials, 20–120 cm, colonial or cespitose; branched rhizomatous, or with branched caudices, becoming ± woody.
Stems

1, erect (straight, stout), glabrous or hairy.

1–5+, erect (straight to ± flexuous distally, often reddish, sometimes brown), usually glabrous, sometimes ± pilose, particularly distally.

Leaves

thin, scabrous, apices mucronate, abaxial faces glabrous (vein areoles indistinct, elongate), adaxial glabrous or sparsely scabrous (var. hesperium);

basal withering by flowering, petiolate to subpetiolate (petioles winged, ciliate, bases dilated, sheathing), blades elliptic-oblanceolate or obovate to suborbiculate, 10–80 × 5–20 mm, cuneate to attenuate, margins crenate-serrate, apices acute to obtuse or rounded;

proximal cauline withering by flowering, sessile or subsessile, blades lance-ovate or oblanceolate to linear-lanceolate, (40–)50–150 × (3–)10–20(–35) mm, progressively reduced distally, bases cuneate, ± decurrent, margins serrate, apices acute to acuminate;

distal sessile, blades oblanceolate to linear, 30–100(–140) mm, only slightly reduced distally, bases cuneate, margins entire.

thin, margins serrate (often sharply, teeth acuminate, mucronulate) to serrate-crenate or subentire, strigose, apices acuminate to acute, mucronulate, abaxial faces glabrous or sparsely to densely strigose-pilose, often pilose on midveins, sometimes on other veins also, adaxial glabrous or sparsely to densely strigose, sometimes ± scabrous;

basal withering by flowering, new vernal rosettes often present, long-petiolate (petioles ± narrowly winged, bases dilated, sheathing, ciliate), blades ovate to elliptic or suborbiculate, (10–)35–150 × (10–)25–75 mm, bases usually deeply cordate, sometimes rounded, margins coarsely, often irregularly serrate, apices sometimes obtuse or rounded;

proximal cauline often withering by flowering, winged-petiolate (becoming shorter and more widely winged distally, petiole bases clasping), blades widely to narrowly ovate, 40–100(–140) × 20–40(–70) mm, reduced distally, bases ± deeply cordate to rounded, margins sharply serrate, apices acuminate;

distal usually sessile or subsessile, rarely short-petiolate, blades ovate to lanceolate, 5–105 × 2–45 mm, bases cordate or rounded to attenuate or cuneate, margins serrate or entire (distalmost), apices acuminate.

Peduncles

0.5–5 cm, ± pilose, bracts 1–3(–5), linear-oblanceolate to -lanceolate, foliaceous, ciliate.

0.3–2 cm, ± pilose, bracts linear-oblanceolate or -lanceolate to linear, foliaceous, distally grading into phyllaries, margins sparsely ciliolate, glabrous.

Involucres

campanulate to cylindric, 3–8 mm.

cylindro-campanulate to cylindric, (3–)4.5–5(–6) mm.

Ray florets

16–50;

corollas white to pinkish or pale blue-violet, laminae 3–10(–14) × 0.5–1.3 mm.

(8–)10–16(–20);

corollas usually blue to purple, seldom whitish or pink, laminae (5–)6–8(–10) × 1.4–1.8 mm.

Disc florets

(13–)20–40(–52);

corollas yellow becoming purple, 2.8–5.8 mm, tubes shorter than funnelform throats, lobes sometimes ± spreading, triangular, 0.4–1.2 mm.

(8–)10–15(–20);

corollas cream-color or light yellow becoming purple, (3–)4–4.5(–5) mm, tubes slightly shorter than funnelform throats, lobes sometimes ± spreading, narrowly triangular to lanceolate, 0.6–0.9 mm.

Phyllaries

in (3–)4–6 series, appressed or slightly spreading, linear-lanceolate to linear (innermost), sometimes slightly dilated distally, ± strongly unequal to subequal (var. hesperium), bases indurate 1/4–1/2, margins scarious, erose, hyaline, sparsely ciliolate, green zones lanceolate to linear-lanceolate, outer sometimes foliaceous (particularly var. hesperium), apices acute to acuminate (outer) or acuminate to caudate (inner), mostly mucronulate, abaxial faces glabrous, adaxial sparsely strigillose.

in (3–)4–6 series, linear-lanceolate to oblong-lanceolate, unequal, bases indurate 1/2–3/4, margins scarious, erose, hyaline, sparsely ciliolate, green zones lanceolate to ± diamond-shaped, apical, apices (often red-tipped) acute to obtuse-acuminate or acuminate, mucronulate, faces glabrous or sparsely strigillose.

Heads

in ample or diffuse to narrow, elongate, leafy, paniculiform arrays, branches ± ascending, rarely secund, branch leaves often longer than pedicels.

[(5–)20–300+] in ± densely paniculiform arrays, branches divaricate to ascending, paniculiform, sometimes ± long-arching, leafy.

Cypselae

gray or tan, obovoid, ± compressed, 1.5–2 mm, 4–5-nerved, faces sparsely strigillose;

pappi white to sordid or tawny, 5.5–6 mm.

dull purple or light brown, obovoid, ± compressed, 2–2.5 mm, 4–5-nerved, faces glabrous;

pappi white or ± rose-tinged, 2.5–4.5 mm.

2n

= 16, 32.

Symphyotrichum lanceolatum

Symphyotrichum cordifolium

Phenology Flowering Aug–Oct.
Habitat Rich, mostly mesic, rocky to loamy soils, open wooded slopes and bluffs, stream banks, moist ledges, swampy woods, border of beech-maple or oak-hickory forets, clearings, thickets, roadsides, along ditches, sometimes weedy in urban areas
Elevation 0–1200 m (0–3900 ft)
Distribution
from FNA
AL; AR; AZ; CA; CO; CT; DC; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK [Introduced in Europe]
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; GA; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; VA; VT; WI; WV; MB; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 5 (5 in the flora).

Varieties of Symphyotrichum lanceolatum are sometimes grouped into two subspecies: subsp. hesperium (var. hesperium) and subsp. lanceolatum (the other four varieties). J. C. Semple and J. G. Chmielewski (1987) provided maps of the five taxa. The ranges of var. hesperium and var. lanceolatum overlap in the prairies and in the boreal zone from Alberta to the Clay Belt of northern Ontario. The ranges of the other three varieties do not overlap with that of var. hesperium, but they all overlap each other and with var. lanceolatum in the Midwest. The ecology and cytogeography of the species were summarized by Chmielewski and Semple (2001). The name Aster tradescantii has sometimes been misapplied to this species.

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

Symphyotrichum cordifolium has been introduced in British Columbia but has not persisted. In a morphometric analysis of infraspecific variation in the northeastern part of the range, A. Legault (1986) showed that the varieties described are not distinct and mostly represent phenotypic variants caused by growing conditions; likewise, diploid and tetraploid races could not be distinguished morphologically.

The type of Aster cordifolius var. laevigatus is conspecific with that of Symphyotrichum cordifolium. This name is the basionym of S. lowrieanum; therefore the latter cannot be considered distinct from S. cordifolium and is not recognized here. Most specimens initially identified as S. lowrieanum in herbaria have been re-determined as S. cordifolium. Some of the specimens, however, appear to correspond to the hybrid between S. cordifolium and S. laeve var. laeve, called S. ×schistosum (Steele) G. L. Nesom (syn. Aster schistosus Steele).

Symphyotrichum ×tardiflorum (Linnaeus) Greuter, Aghababian & Wagenitz [syn. Aster tardiflorus Linnaeus, A. novi-belgii Linnaeus subsp. tardiflorus (Linnaeus) A. G. Jones, A. novi-belgii var. tardiflorus (Linnaeus) A. G. Jones, Symphyotrichum novi-belgii (Linnaeus) G. L. Nesom var. tardiflorum (Linnaeus) G. L. Nesom] is the F1 hybrid between S. cordifolium and S. puniceum (J. Labrecque & Brouillet 1996; G. L. Nesom 1997; W. Greuter et al. 2005). Aster tardiflorus forma vestitus (Fernald) Fernald or var. vestitus Fernald is a hairy variant of the hybrid and is not recognized here; hairiness may be related to whichever species is the maternal parent. A. G. Jones (1989) reported hybrids with S. drummondii and S. urophyllum. She believed that var. moratum may be a hybrid with or an introgressant from S. drummondii, but this is not accepted by all authors. Symphyotrichum ×finkii (Rydberg) G. L. Nesom (syn. Aster finkii Rydberg), may be the hybrid of S. cordifolium and S. shortii. All such putative hybrids need to be confirmed.

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

Key
1. Outer phyllaries 2/3 + length of inner ones; heads usually subtended by large foliaceous bracts; cordilleras and prairies (subsp. hesperium)
var. hesperium
1. Outer phyllaries 1/3 – 2/3 length of inner ones; heads not usually subtended by large foliaceous bracts; prairies eastwards (subsp. lanceolatum)
→ 2
2. Stems stout, moderately to densely short-woolly from bases; Great Lakes region to se Manitoba
var. hirsuticaule
2. Stems stout to slender, glabrous or at most hairy in lines at bases
→ 3
3. Heads congested on lateral branches of arrays; involucres 3–4 mm; midwestern United States, s Ontario, s Quebec
var. interior
3. Heads not congested or congested only distally on lateral branches of arrays; involucres 3.6–5.6 mm (mostly longer than 4 mm)
→ 4
4. Leaves broadly oblanceolate, not much reduced in arrays; involucres usually 4–5.5 mm; rays white
var. latifolium
4. Leaves linear to oblanceolate, reduced in arrays; involucres 3.5–5(–6) mm; rays white to purplish
var. lanceolatum
Source FNA vol. 20. FNA vol. 20, p. 501.
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. 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. 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, S. ×amethystinum
Subordinate taxa
S. lanceolatum var. hesperium, S. lanceolatum var. hirsuticaule, S. lanceolatum var. interior, S. lanceolatum var. lanceolatum, S. lanceolatum var. latifolium
Synonyms Aster lanceolatus Aster cordifolius, Aster cordifolius var. alvearius, Aster cordifolius var. furbishiae, Aster cordifolius var. incisus, Aster cordifolius subsp. laevigatus, Aster cordifolius var. laevigatus, Aster cordifolius var. lanceolatus, Aster cordifolius var. moratus, Aster cordifolius var. polycephalus, Aster cordifolius var. racemiflorus, Aster cordifolius subsp. sagittifolius, Aster cordifolius var. sagittifolius, Aster finkii var. moratus, Aster leiophyllus, Aster lowrieanus, Aster lowrieanus var. incisus, Aster lowrieanus var. lanceolatus, Aster sagittifolius, S. cordifolium var. furbishiae, S. cordifolium var. lanceolatum, S. cordifolium var. moratum, S. cordifolium var. polycephalum, S. cordifolium var. racemiflorum, S. lowrieanum, S. sagittifolium
Name authority (Willdenow) G. L. Nesom: Phytologia 77: 284. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 278. (1995)
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