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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 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

Habit Annuals, (10–)30–150 cm; tap-rooted. Perennials, 30–150(–200) cm, colonial; long-rhizomatous (rhizomes usually white, thick, contorted).
Stems

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

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

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.

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.

Peduncles

(0.2–)0.5–4 cm, bracts 4–8(–17).

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

Involucres

cylindric to turbinate, 5–7(–8.2) mm.

campanulate to cylindric, 3–8 mm.

Ray florets

16–30(–54) in 1–3 series;

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

16–50;

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

(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.

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–)4–6 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.

Heads

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

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

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.

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.

Symphyotrichum subulatum

Symphyotrichum lanceolatum

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; 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]
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 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.)

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. 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, p. 480. FNA vol. 20.
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. 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
Subordinate taxa
S. subulatum var. elongatum, S. subulatum var. ligulatum, S. subulatum var. parviflorum, S. subulatum var. squamatum, S. subulatum var. subulatum
S. lanceolatum var. hesperium, S. lanceolatum var. hirsuticaule, S. lanceolatum var. interior, S. lanceolatum var. lanceolatum, S. lanceolatum var. latifolium
Synonyms Aster subulatus Aster lanceolatus
Name authority (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) (Willdenow) G. L. Nesom: Phytologia 77: 284. (1995)
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