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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

late purple American-aster, late purple aster, late purple or spreading aster

Habit Annuals, (10–)30–150 cm; tap-rooted. Perennials, 10–100(–120) cm, cespitose; with short, thick, woody caudices, tangled or sometimes cormoid, and long rhizomes.
Stems

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

1–5+, ascending to erect (often stout, light to dark brown), sparsely to densely scabroso-hirsute to cinereo-puberulent, or villous distally.

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.

(light to dark green) thick and often stiff (margins flat, sometimes undulate), scabrous;

basal early deciduous, subpetiolate (petioles winged, sheathing), blades spatulate to obovate, 30–70 × 10–30 mm, bases cuneate, margins entire to ± serrulate, scabrous, apices acute to rounded, faces scabroso-hirsute;

proximal cauline sessile, blades usually ovate to lanceolate, rarely spatulate, (20–)30–70(–100) × 10–30(–40) mm, reduced distally, bases strongly cordate-clasping to auriculate-amplexicaul (broadened below constriction), apices acute, faces (grayish green) rugulose, hairy (abaxial inconspicuously veined, adaxial reticulately veined, hairier along veins);

distal sessile, blades narrowly to broadly ovate, 15–35 × 4–13 mm, much reduced on branches, bases strongly cordate-clasping to auriculate-amplexicaul, apices usually acute, sometimes obtuse, mucronate to white-spinulose, faces scabrous, sometimes sparsely to moderately stipitate-glandular.

Peduncles

(0.2–)0.5–4 cm, bracts 4–8(–17).

stiffly ascending, slender, 2–10(–15) cm, scabroso-hirsute to cinereo-puberulent, bracts appressed to spreading, linear, 1–5 mm, grading into phyllaries.

Involucres

cylindric to turbinate, 5–7(–8.2) mm.

campanulate, 5.5–12 mm.

Ray florets

16–30(–54) in 1–3 series;

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

12–24+;

corollas light lavender-violet to mauve, rarely white to pinkish, laminae 10–18(–20) × 1–3 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.

20–50;

corollas yellow, cream, or white turning purple, (4.5–)5.5–7.5 mm, tubes shorter than narrowly funnelform throats, lobes triangular, 0.5–1 mm (glabrous or lobes thinly puberulent).

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 4–7(–8) series, appressed or often slightly recurved-spreading or squarrose, ovate-lanceolate to linear, strongly unequal, bases (tan) ± indurate in proximal 1/3–1/2, margins hyaline, erose, distally scabroso-ciliolate to ciliolate, green zones diamond-shaped, in distal 1/5–1/3, apices (outer) obtuse to acute, appressed to squarrose, (inner) acuminate, often purplish red, faces strigillose or cinereo-puberulent abaxially and near tip adaxially, sometimes moderately stipitate-glandular distally.

Heads

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

in paniculiform arrays, branches divaricate (heads 1–5+ per branch), terminal shoot often not flowering.

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.

dull purple or brown, obovoid to oblong-obovoid, not compressed, 2–3.5 mm, 7–10-nerved (faint), faces sericeous or strigillose;

pappi tawny, sometimes rose-tinged, 4.5–6.5 mm.

Symphyotrichum subulatum

Symphyotrichum patens

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; CT; DC; DE; FL; GA; IL; IN; KS; KY; LA; MA; MD; ME; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; WV
[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 3 (3 in the flora).

(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. Involucres turbinate, 8–12 mm; phyllaries in 5–7 series, appressed, obtuse, densely strigillose to canescent, eglandular or sparsely glandular; mostly w of Mississippi River, Interior Uplands of e United States
var. patentissimum
1. Involucres campanulate, 5.5–7.5 mm; phyllaries in 4–5 series, squarrose, acute to acuminate, sparsely to densely strigillose, sparsely to densely stipitate-glandular
→ 2
2. Plants slender; involucres 5.5–6.5 mm; mid phyllaries 0.7–1 mm, faces densely strigillose, sparsely stipitate-glandular; Alabama to Texas, n to Kansas
var. gracile
2. Plants robust; involucres 6–7.5 mm; mid phyllaries 1–1.2 mm, faces densely glandular and sparsely strigillose; mostly e of Mississippi River
var. patens
Source FNA vol. 20, p. 480. FNA vol. 20, p. 488.
Parent taxa Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus
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. novi-belgii, S. oblongifolium, S. ontarionis, S. oolentangiense, S. parviceps, 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. patens var. gracile, S. patens var. patens, S. patens var. patentissimum
Synonyms Aster subulatus Aster patens, Virgulus patens
Name authority (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) (Aiton) G. L. Nesom: Phytologia 77: 288. (1995)
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