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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

Short's aster

Habit Annuals, (10–)30–150 cm; tap-rooted. Perennials, 30–150 cm, cespitose; short-rhizomatous or with ± woody caudices.
Stems

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

1–5+, ascending to erect (straight, sometimes stout), proximally glabrous, distally ± densely hirtellous.

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, margins often slightly revolute, scabrous, apices mucronate or mucronulate, abaxial faces sparsely to moderately hispid, especially along veins, adaxial glabrous (midveins scabrous, veins marked) to strigoso-hispid (basal);

basal withering by flowering (new winter rosette sometimes developing), petiolate (petioles 1–2 times as long as blades, sometimes narrowly winged, sheathing, densely pilose or hirsute), blades ovate to lance-ovate, 10–60 × 10–35 mm, deeply to shallowly cordate or rounded, margins crenate or crenate-serrate, apices obtuse to acute;

proximal cauline mostly persistent, narrowly petiolate (petioles slender, progressively reduced distally, bases at most slightly clasping), blades ovate to lanceolate, 50–150 × 20–60(–70) mm, progressively reduced distally, bases shallowly cordate to subcordate, truncate, or rounded, sometimes oblique, margins entire, scabrous or shallowly crenate-serrate (proximal), apices acute to acuminate;

distal short-petiolate (petioles sometimes narrowly winged, sometimes slightly clasping) or sessile (distalmost, rameal), blades ovate to lanceolate (rameal lance-linear to linear, sharply smaller), 8–80 × 1–40 mm, gradually reduced distally, bases rounded to cuneate or attenuate, margins entire to subentire, apices acute to acuminate.

Peduncles

(0.2–)0.5–4 cm, bracts 4–8(–17).

0.2–3(–5) cm, densely hirtellous, bracts 3–10+, ovate or lanceolate to subulate, grading into phyllaries.

Involucres

cylindric to turbinate, 5–7(–8.2) mm.

cylindro-campanulate, 4–6 mm.

Ray florets

16–30(–54) in 1–3 series;

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

13–15(–20);

corollas usually blue or purple-blue, seldom pinkish or white, laminae (10–)11–16 × 1.3–3.1 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.

16–23(–28?);

corollas light yellow becoming reddish purple, 4.6–7 mm, tubes shorter than funnelform throats, lobes lanceolate, 0.4–1.1 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 4–5(–6) series, appressed, lanceolate or oblong-lanceolate (outer) to linear-lanceolate or linear (inner), strongly unequal, bases indurate 1/2–5/6, margins scarious, erose, hyaline, ciliolate, green zones lanceolate to diamond-shaped (midveins below green zone sometimes inflated and brownish), apices acute to acuminate, often involute, mucronulate, faces strigilloso-hirsutulous.

Heads

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

usually in open, diffuse to narrow, paniculiform arrays, sometimes racemiform, branches widely spreading, usually divaricate to arching, sometimes ascending, sometimes ± secund, abundantly leafy.

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, oblong-obovoid, compressed, 2.5–3.7 mm, 4–7-nerved, faces glabrous;

pappi reddish brown, tawny, or rose-tinged, 4–6.2 mm.

2n

= 16, 32.

Symphyotrichum subulatum

Symphyotrichum shortii

Phenology Flowering Aug–Oct.
Habitat Open, often thin, rocky, well-drained soils, oak-hickory woods, edges of woods, thickets, calcareous hammocks, wooded stream banks or cliffs, roadsides
Elevation 100–500 m (300–1600 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; IA; IL; IN; KY; MD; MI; MN; MS; NC; PA; TN; VA; WI; WV; ON
[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.)

Symphyotrichum shortii is of conservation concern along the whole periphery of its range, notably in Canada; there is a report from the District of Columbia but the species is not established there. Aster shortii Lindley forma gronemannii Benke is a roseate phenotype, and forma candidus Benke a white one, forma shortii being the normal blue or purple one. They are not recognized here.

(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
Source FNA vol. 20, p. 480. FNA vol. 20, p. 505.
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. 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. 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
Synonyms Aster subulatus Aster shortii, Aster camptosorus
Name authority (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) (Lindley) G. L. Nesom: Phytologia 77: 291. (1995)
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