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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

wavy-leaf American-aster, wavyleaf aster, waxyleaf aster

Habit Perennials, 30–150(–200) cm, colonial; long-rhizomatous (rhizomes usually white, thick, contorted). Perennials, 30–160 cm, cespitose; short-rhizomatous or with branched, woody caudices.
Stems

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

1–3+, erect (straight, brittle), hirtellous to glabrescent proximally to densely hirtellous 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 scabrous, abaxial faces hirtellous, densely so on midveins, adaxial usually scabrous, sometimes strigose or hirsute, rarely glabrate;

basal withering by flowering (sometimes new winter rosette developing), petiolate (petioles purplish, narrowly winged, bases dilated and sheathing, hirsute), blades oblong-ovate or ovate to widely ovate, (10–)35–60(–140) × (10–)15–70 mm, bases usually cordate or subcordate to rounded, sometimes attenuate, margins shallowly crenate-serrate to subentire, apices obtuse or rounded, mucronulate;

proximalmost cauline withering by flowering, proximal persistent, winged-petiolate, distally more widely winged or ± sessile, wings widening abruptly at strongly auriculate-clasping petiolar bases, blades ovate to lanceolate, 30–120(–140) × (10–)20–50 mm, reduced distally, bases cordate- or auriculate-clasping (sessile), margins crenate-serrate or entire, apices acute or acuminate, mucronate;

distal sessile, blades lance-ovate to oblong or lanceolate to linear-lanceolate, sometimes pandurate (branch leaves ovate to lanceolate, sharply smaller), 4–100 × 0.5–26 mm, reduced distally, bases ± clasping, sheathing, margins serrulate or entire, apices acute or acuminate to long-acuminate.

Peduncles

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

well developed, 0.3–3(–5) cm, branches to 10 cm, spreading, bracteate, densely hirtellous to strigillose, bracts 3–10+, firm, appressed, subulate (2–3 mm), grading into phyllaries.

Involucres

campanulate to cylindric, 3–8 mm.

campanulate to cylindro-campanulate, 3.8–5.5 mm.

Ray florets

16–50;

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

12–16(–25);

corollas usually blue to purple, sometimes lilac, laminae 6–12 × 1.4–2.5 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.

15–22(–25);

corollas cream or light yellow becoming purple, 4–5.8 mm, tubes slightly shorter than funnelform throats, lobes lanceolate, 0.5–0.9 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 4–5(–6) series, appressed or outer spreading, oblong-lanceolate (outer) to linear-oblanceolate (inner) or linear (innermost), strongly unequal, bases indurate 1/2–2/3, margins scarious, erose, hyaline, ciliolate, green zones diamond-shaped to lanceolate, apices acute to acuminate or obtuse, often ± involute, often mucronulate, sometimes tips purplish, abaxial faces hirsutulous, adaxial sparsely so distally.

Heads

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

in open, narrow to wide paniculiform arrays, branches widely spreading, divaricate to ascending, sometimes secund, ± densely 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 to light brown or tan, oblong-obovoid, compressed, 1.7–2.2 mm, 3–4-nerved, faces strigillose;

pappi cream or rose-tinged, 3.5–5 mm.

2n

= 16, 32.

Symphyotrichum lanceolatum

Symphyotrichum undulatum

Phenology Flowering Aug–Oct.
Habitat Dry or well-drained, loamy or rocky soils, open decidous woods, borders, clearings, dry hammocks, sandhills, open-wooded bluffs underlain by sandstone or limestone
Elevation 200–1500 m (700–4900 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
CT; DC; DE; FL; GA; IL; IN; KY; LA; MA; MD; ME; MS; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; NS; ON; Ala
[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 undulatum is of conservation concern in Illinois and Nova Scotia. Hybridization with S. drummondii and S. oolentangiense has been by reported by A. G. Jones (1989), but some specimens so annotated represent phenotypic variation of S. undulatum. Symphyotrichum undulatum is sometimes confused with members of the S. patens complex due to its auriculate-clasping, more or less pandurifom cauline leaves.

(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. 506.
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. 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. 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 undulatus, Aster asperifolius, Aster baldwinii, Aster claviger, Aster corrigiatus, Aster gracilescens, Aster linguiformis, Aster loriformis, Aster mohrii, Aster proteus, Aster sylvestris, Aster triangularis, Aster truellius, Aster undulatus var. diversifolius, Aster undulatus var. loriformis
Name authority (Willdenow) G. L. Nesom: Phytologia 77: 284. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995)
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