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annual saltmarsh American-aster, annual saltmarsh aster, annual saltmarsh or eastern annual saltmarsh aster, aster subulé, eastern annual saltmarsh aster, Southwestern annual saltmarsh aster

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

Habit Annuals, (10–)30–150 cm; tap-rooted. Perennials, 17–100(–140) cm, loosely to densely colonial or sometimes cespitose; long-rhizomatous.
Stems

1, erect (often with purple or purplish brown areas), glabrous or glabrate, sometimes strigillose in leaf axils.

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

Leaves

thin (green to dark green), margins often strigilloso-ciliolate, faces glabrous;

basal withering by flowering, long-petiolate (petiole bases sheathing), sparsely ciliate, blades ovate to oblanceolate, 10–90 × 6–14 mm, bases attenuate to cuneate, rounded, margins entire or serrulate or crenulate, apices rounded, obtuse, or acute;

proximal cauline withering by flowering, petiolate, subpetiolate, or sessile, blades narrowly lanceolate or subulate, 20–100(–200) × 1.5–10(–20) mm, bases attenuate, margins subentire, entire, or serrulate, apices acute to acuminate;

distal sessile, blades narrowly lanceolate to subulate, 5–113 × 0.5–5.5 mm, apices acuminate.

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

(0.2–)0.5–4 cm, bracts 4–8(–17).

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 to turbinate, 5–7(–8.2) mm.

campanulate, 6–9 mm.

Ray florets

16–30(–54) in 1–3 series;

corollas white, pink, or lavender, laminae 1.3–7 × 0.2–1.3 mm.

15–35;

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

Disc florets

4–10(–13);

corollas yello, sometimes tinged with purple, 3.4–5.2 mm, throats narrowly funnelform, lobes ± spreading to erect, narrowly triangular, 0.3–0.7 mm, glabrous.

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 3–5 series, broadly or narrowly lanceolate to subulate, unequal, bases indurate, margins hyaline, often purple-tinged, entire, green zones lanceolate (usually narrow, sometimes broad and covering most of distal portion), apices acute, 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

(10–) 30–100(–150), in open, diffuse, paniculiform arrays.

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

Cypselae

light brown to purple, narrowly obovoid to fusiform, sometimes ± compressed, (1.2–)1.5–2.7(–3) mm, 5-nerved, faces sparsely strigillose;

pappi white, (3–)3.5–5.5 mm.

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

pappi sordid to yellowish, 4–6 mm.

Symphyotrichum subulatum

Symphyotrichum novi-belgii

Phenology Late Aug–Oct(–Nov).
Habitat Woods and open places, especially sandy soils
Elevation 0–1400[–2300] m (0–4600[–7500] ft)
Distribution
from FNA
AL; AR; AZ; CA; CT; DE; FL; GA; IL; IN; KS; LA; MA; MD; ME; MI; MS; NC; NE; NH; NJ; NM; NV; NY; OH; OK; PA; RI; SC; TN; TX; UT; VA; NB; ON; Mexico; Central America; South America; West Indies; Bermuda [Widely introduced worldwide]
[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

Varieties 5 (5 in the flora).

Five varieties of Symphyotrichum subulatum are recognized for North America based on differences in chromosome number, ray lamina color and size, array shapes, number of series of ray florets, number of disc and ray florets, and other, more cryptic characters (S. D. Sundberg 2004). These varieties were treated as species by G. L. Nesom (1994b, 2005d). Variety ligulatum is apparently an obligate outcrosser and is the least variable variety (Sundberg). Other varieties are self-compatible, which could facilitate the fixation of mutations in populations.

The five varieties are nearly entirely allopatric, and intermediates between pairs of varieties are not uncommon where they approach one another. Populations that are intermediate in ray lamina size between vars. ligulatum and parviflorum are widespread in southern Texas, New Mexico, Arizona, and northern Mexico. Intermediates between vars. elongatum and parviflorum and between vars. elongatum and subulatum occur in Florida. Despite these observations, hybridization experiments and chromosome number differences suggest that the varieties are mostly reproductively isolated (S. D. Sundberg 1986, 2004).

In older floras the name Aster exilis Elliott has been applied to Symphyotrichum subulatum vars. ligulatum and parviflorum. The status of this name is uncertain; the type specimen has been lost and the description of the plant is inadequate for determining the taxon to which the name should be applied (G. L. Nesom 1994b; S. D. Sundberg 2004).

(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. Ray laminae lavender to blue, (3.5–)4.5–7 × 0.9–1.3 mm, drying in 3–5 coils; ray florets in 1 series; disc florets (20–)33–50 (sc United States)
var. ligulatum
1. Ray laminae white to pink or lavender, 1.3–3.5(–4.2) × 0.2–0.6 mm, drying in (0–)1–3(–4) coils; ray florets in 1–3 series; disc florets 3–23
→ 2
2. Ray laminae pink to lavender, (2–)2.5–3.5(–4.2) × 0.3–0.6 mm, drying in 2–3(–4) coils; disc florets 11–23 (Florida, West Indies)
var. elongatum
2. Ray laminae usually white, rarely pink or lavender, 1.3–3 × 0.2–0.5 mm, drying in 1 coil or curling; disc florets (3–)4–15
→ 3
3. Ray laminae longer than pappi; phyllaries 30–42; pappi 3.5–3.8(–4.2) mm; w United States
var. parviflorum
3. Ray laminae shorter to slightly longer than pappi; phyllaries 18–30; pappi 3.5–5.5 mm; e and se United States
→ 4
4. Green zones of phyllaries narrowly to broadly lanceolate, extending phyllary length; ray laminae 0.2–0.5 mm wide; disc florets 3.8–4.6(–4.9) mm; salt marshes, e North America and Gulf Coast
var. subulatum
4. Green zones of phyllaries broadly lanceolate, nearly absent from proximal portion; ray laminae 0.2–0.3 mm wide; disc florets 3.2–4.1 mm; adventive, s United States
var. squamatum
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. 480. FNA vol. 20, p. 528.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium 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. 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. 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. subulatum var. elongatum, S. subulatum var. ligulatum, S. subulatum var. parviflorum, S. subulatum var. squamatum, S. subulatum var. subulatum
S. novibelgii var. crenifolium, S. novibelgii var. elodes, S. novibelgii var. novibelgii, S. novibelgii var. villicaule
Synonyms Aster subulatus Aster novi-belgii
Name authority (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 287. (1995)
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