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arrow-leaf American-aster, white arrowleaf aster, white arrowleaf or arrowleaf aster

aster de New York, New York American-aster, New York aster

Habit Perennials, 40–120(–200) cm, cespitose; short-rhizomatous or with stout, branched caudices. Perennials, 17–100(–140) cm, loosely to densely colonial or sometimes cespitose; long-rhizomatous.
Stems

1–5+, erect (straight to slightly flexuous, brittle, sometimes stout), proximally glabrous or glabrate, distally sparsely pilose.

1–5+, erect (straight, stout to slender, often reddish), glabrous and hairy in lines distally or sometimes wholly strigoso-pilose (var. villicaule).

Leaves

thin, margins usually shallowly, sometimes deeply serrate, rarely entire (distal), (piloso- to strigoso-)ciliate to scabrous (distal), apices mucronate, abaxial faces moderately pilose, ± densely so on midveins, adaxial glabrate to sparsely pilose or scabrous;

basal usually withering by flowering, sometimes persistent, long-petiolate (5–15 cm, petioles not or narrowly winged, sheathing), blades ovate to lance-ovate or lanceolate, 25–120 × 15–50 mm, bases usually shallowly, sometimes deeply, cordate to truncate or rounded, apices acute, sometimes rounded;

proximal cauline sometimes deciduous at flowering, winged-petiolate (petioles distally usually broader-winged, clasping), blades ovate to lanceolate, 50–120 × 20–50 mm, gradually reduced distally, bases usually truncate or rounded to attenuate, sometimes cordate, apices usually acute or acuminate, sometimes nearly caudate;

distal ± shortly winged-petiolate or sessile, blades lance-ovate or lanceolate to linear-lanceolate, 10–100 × 1–25 mm, reduced distally, bases attenuate to cuneate, margins entire to subentire, scabrous, apices acuminate to subcaudate.

thick, firm, ± fleshy, margins scabrous, apices mucronate, faces glabrous, abaxial midveins sometimes villosulous (var. villicaule);

basal withering by flowering, petiolate (petioles winged, bases sheathing), blades ovate to ovate-lanceolate or lanceolate, 17–60+ × 6–11+ mm, bases attenuate to cuneate, apices obtuse;

proximal cauline withering by flowering, sessile or widely winged-petiolate (petioles clasping), blades lance-ovate or -obovate to elliptic to linear-lanceolate, 40–200 × 4–40 mm, bases cuneate or sometimes slightly attenuate, sometimes rounded or slightly auriculate, slightly clasping, apices acute to acuminate;

distal sessile, blades lance-ovate to linear-lanceolate, 13–62 × 3–15 mm, progressively reduced distally, bases cuneate or ± rounded, sometimes slightly auriculate, ± clasping, margins sparsely serrulate or entire.

Peduncles

0.3–2 cm, sparsely pilosulous to glabrate, bracts many, ascending, linear to subulate, 2–4 mm, grading into phyllaries.

4–41 mm, glabrous or moderately pilose, bracts 1–3, lanceolate or ovate to linear-oblanceolate, subtending ones sometimes exceeding involucres, sometimes grading into phyllaries.

Involucres

cylindric, (4–)4.5–6(–7) mm.

campanulate, 6–9 mm.

Ray florets

8–15(–20);

corollas mostly white to pale pink or lilac or light blue, laminae 4.5–8(–10) × 0.8–1.5 mm.

15–35;

corollas usually blue-violet or purple, rarely pink or white, laminae (6–)10–19 × 0.9–2.1 mm.

Disc florets

(8–)10–15(–20);

corollas whitish to cream becoming pink, (3.5–)4–5 mm, tubes shorter than funnelform throats (with hairs), lobes lanceolate, 0.4–0.7 mm.

28–68;

corollas yellow becoming reddish brown to purple, 4–7.5 mm, tubes shorter than funnelform-campanulate throats, lobes lanceolate, 1–1.5 mm.

Phyllaries

in 4–6 series, appressed or recurved-spreading, subulate (outer) to linear-lanceolate (inner), unequal, bases indurate 1/3–1/2+, margins scarious, hyaline, erose, sparsely ciliolate (mostly distally), green zones linear-lanceolate (outer) to linear (inner), apices long-acuminate to caudate, recurved, hyaline-mucronate to aristate, tips often purple, faces glabrous.

in 3–4 series, oblong-oblanceolate or -spatulate (outer) or oblong-lanceolate to linear-lanceolate or linear (inner), ± unequal to subequal, bases indurate 1/5–1/3, margins hyaline, scarious, erose and sparsely ciliolate distally, green zones lanceolate, sometimes foliaceous, apices spreading to ± squarrose, usually acute to obtuse or ± long-acuminate, mucronulate, faces glabrous.

Heads

(crowded) in dense, elongate, paniculiform arrays, branches stiffly ascending to erect (sometimes arched when long, peduncles then often secund), usually racemiform, sometimes paniculiform, leafy.

in open to dense, paniculiform arrays, branches ± divaricate to ascending, leafy with remote, small, gradually reduced branch leaves.

Cypselae

tan to brown or dull purple (nerves stramineous), obovoid, ± compressed, 1.8–2.5 mm, 4–6-nerved, faces glabrous or glabrate or very sparsely strigillose;

pappi white or rose-tinged, 3–4 mm.

tan to brown, obovoid, compressed, 2–4 mm, 4–6-nerved, faces sparsely strigose to glabrate;

pappi sordid to yellowish, 4–6 mm.

2n

= 16.

Symphyotrichum urophyllum

Symphyotrichum novi-belgii

Phenology Flowering Aug–Oct. Late Aug–Oct(–Nov).
Habitat Open, dry or mesic, sandy or loamy, sometimes rocky soils, limestone pavements, glades, ravines, open oak, sassafras, aspen, or pine woods, edges of woods, moist or dry, rocky bluffs, savanna, wooded banks, stabilized dunes, fields, roadsides, hedgerows, railroads Woods and open places, especially sandy soils
Elevation 40–300+ m (100–1000+ ft) 0–1400[–2300] m (0–4600[–7500] ft)
Distribution
from FNA
AL; AR; FL; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MS; NC; ND; NE; NJ; NY; OH; OK; PA; SC; TN; VA; VT; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; FL; GA; IL; KS; LA; MO; NC; NE; NM; OK; SC; TX; Mexico (Coahuila)
[WildflowerSearch map]
[BONAP county map]
Discussion

The name Aster sagittifolius Wedemeyer ex Willdenow has been misapplied to this taxon; our interpretation of the type of this entity concords with that of A. G. Jones (1980), i.e., that it is conspecific with the type of Symphyotrichum cordifolium or a garden hybrid involving the latter. Aster sagittifolius forma hirtellus (Lindley) Shinners is not recognized here.

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

varieties 4 (4 in the flora)

Symphyotrichum novi-belgii is morphologically variable (J. Labrecque and L. Brouillet 1996) and this variation appears to have both genetic and environmental bases. The name Aster foliaceus has been misapplied to members of this complex in eastern North America; various other names also have been misused at the specific or subspecific levels. These are clarified under the varieties below. Hybrids of S. novi-belgii, probably mostly var. novi-belgii or var. elodes, have been reported with S. lanceolatum and S. lateriflorum.

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

Key
1. Proximal stems uniformly and densely hirsute; Maine, New Brunswick, and adjacent Quebec
S. novibelgii var. villicaule
1. Proximal stems glabrous or slightly hirsute in lines
→ 2
2. Leaves: lengths 4–5 times widths, bases strongly clasping; plants robust, compact; New Brunswick
S. novibelgii var. crenifolium
2. Leaves: lengths 7–10+ times widths, bases ± clasping or subclasping; plants slender to ± compact
→ 3
3. Leaves lance-ovate or lanceolate to oblanceolate, lengths less than 10 times widths, bases ± clasping
S. novibelgii var. novibelgii
3. Leaves linear-lanceolate, lengths more than 10 times widths, bases subclasping
S. novibelgii var. elodes
Source FNA vol. 20, p. 506. FNA vol. 20, p. 528.
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. 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. 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. 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. novibelgii var. crenifolium, S. novibelgii var. elodes, S. novibelgii var. novibelgii, S. novibelgii var. villicaule
Synonyms Aster urophyllus, Aster sagittifolius var. dissitiflorus Aster novi-belgii
Name authority (Lindley ex de Candolle) G. L. Nesom: Phytologia 77: 294. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 287. (1995)
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