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aster éricoïde, heath American-aster, heath-leaf aster, little gray aster, rayless alkali aster, tuft white prairie aster, white heath aster

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

Habit Perennials, 20–80(–100) cm, colonial or cespitose, eglandular; branched rhizomatous, or with ± cormoid, branched, woody caudices. Perennials, 30–160 cm, cespitose; short-rhizomatous or with branched, woody caudices.
Stems

1–3+, ascending to erect (grayish brown to brown), sparsely to densely hispido-strigose, sometimes glabrescent proximally.

1–3+, erect (straight, brittle), hirtellous to glabrescent proximally to densely hirtellous distally.

Leaves

usually all except rameal withered by flowering, (light grayish green) firm apices ± white-spine-tipped (often with clusters of smaller leaves in axils);

basal sessile, blades (3-nerved) oblanceolate to oblong or spatulate, 10–50 × 10–25 mm, bases attenuate, margins usually entire, rarely remotely serrate, scabrous, apices rounded to obtuse, faces usually sparsely hairy, often glabrous;

proximal cauline sessile, blades (1- or 3-nerved) linear to lanceolate or oblong, 10–40(–60) × 1.5–4(–7) mm, reduced distally, bases cuneate, coarsely ciliate, margins entire, coarsely ciliate, apices acute or obtuse, faces moderately to densely strigose or hirsute;

distal sessile, blades oblong-ovate, 10–40 × 1.5–3.5 mm, abruptly reduced distally, bases cuneate, margins entire, apices acute, faces moderately to densely strigose.

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

0.5–1(–2) cm or subsessile, densely hairy, bracts dense, linear to narrowly lanceolate, usually reflexed, sometime appressed to ascending, 1.5–5(–6) mm, densely hairy, grading into phyllaries.

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

cylindric to campanulate, 2.5–4.5(–5) mm.

campanulate to cylindro-campanulate, 3.8–5.5 mm.

Ray florets

(8–)10–18(–20);

corollas usually white, rarely pink or bluish, laminae 6–12(–20) × 0.7–1.2 mm.

12–16(–25);

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

Disc florets

6–12(–20);

corollas yellow becoming brown, 2.5–4 mm, throats narrowly funnelform, lobes triangular, 0.5–0.6 mm, glabrous.

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 series, oblanceolate to ± spatulate, unequal, firm, bases (whitish to tan) ± indurate in proximal 1/2–2/3, margins hyaline, scabrous proximally, green zones diamond-shaped, in distal 1/2, apices spine-tipped, (outer) spreading to reflexed or squarrose, faces (outer) sparsely to densely hispid, scabroso-hirsute adaxially, (inner) glabrous.

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

(1–200+) in paniculiform arrays, branches fastigiate or arrays often pyramidal, racemiform, secund, crowded.

in open, narrow to wide paniculiform arrays, branches widely spreading, divaricate to ascending, sometimes secund, ± densely leafy.

Cypselae

deep purple turning brown, obovoid to oblong-obovoid, ± falcate, not compressed, 1.2–2 × 0.4–0.6 mm, 7–9-nerved (faint), faces sericeous or densely strigillose;

pappi whitish, 3–4 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 ericoides

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
AR; AZ; CO; CT; DC; DE; IA; ID; IL; IN; KS; MA; MD; ME; MI; MN; MO; MS; MT; ND; NE; NJ; NM; NY; OH; OK; OR; PA; RI; SD; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NT; ON; QC; SK; n Mexico
[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 2 (2 in the flora).

Symphyotrichum ericoides resembles S. pilosum var. pilosum, which has larger heads, longer rays, and phyllaries that are not spine-tipped, though the revolute margins can make them appear so. Two subspecies and four weakly separated varieties of S. ericoides were recognized by A. G. Jones (1978). Tetraploids of var. ericoides on the eastern prairies can be difficult to distinguish from S. falcatum. A number of aster cultivars are sold under the name “Aster ericoides.” These are all derived from European garden plants and are either cultivars of S. dumosum, S. lateriflorum, S. pilosum, or S. racemosum, or hybrids involving one of those species and another taxon. The misapplication of the epithet ericoides dates back to the nineteenth century and has persisted in the horticultural literature.

(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. Plants colonial, rhizomatous, not cormoid; involucres cylindro-campanulate when fresh
var. ericoides
1. Plants cespitose, with cormoid caudices, not strongly rhizomatous; involucres broadly campanulate when fresh
var. pansum
Source FNA vol. 20, p. 494. FNA vol. 20, p. 506.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus 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. 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
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. ericoides var. ericoides, S. ericoides var. pansum
Synonyms Aster ericoides, Lasallea ericoides, Virgulus ericoides 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 (Linnaeus) G. L. Nesom: Phytologia 77: 280. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995)
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