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perennial saltmarsh American-aster, perennial saltmarsh aster

bushy American-aster, bushy aster, rice button aster

Habit Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. Perennials, (20–)30–100 cm, colonial or cespitose; usually long-rhizomatous, often thick, woody, sometimes short, or with short, stout caudices.
Stems

1–5+, ascending to erect (often with purple or purplish brown areas, flexuous, wiry), little-branched, usually glabrous, sometimes hairy in lines distally.

1–5+, erect (straight, often slender, brittle), densely or sparsely strigose to glabrescent or glabrate.

Leaves

thick (fleshy), margins entire, faces glabrous;

basal withering by flowering (new winter rosettes appearing at flowering), petiolate (petioles sheathing), blades ovate or oblanceolate, 15–20 × 5–15 mm, bases cuneate, apices rounded;

proximal cauline withering by flowering, usually sessile, blades lanceolate, linear-lanceolate or -oblanceolate, to linear, 7–80(–150) × 1–6 (–12) mm, bases attenuate, margins entire, apices acuminate to acute;

distal sessile, blades narrowly lanceolate to subulate, 10–110 × 0.5–5 mm, apices acuminate.

firm, margins entire to crenulate-serrate, recurved, scabrous, apices sharply white-mucronate, abaxial faces glabrous or glabrate to sparsely strigillose, adaxial glabrous or glabrate to submarginally scabrous (short-strigose), cauline withering by flowering (except on array branches), often with axillary leaf clusters;

basal withering by flowering, petiolate, petioles winged, sheathing, strigose-ciliate, blades oblanceolate to spatulate (often declined), 8–50 × 3–15 mm, bases attenuate to cuneate, margins crenate-serrate, apices obtuse or rounded to ± acute;

proximal cauline (mostly declined) subpetiolate (petioles widely winged, clasping) or sessile (then not or barely clasping), blades linear-oblanceolate, 25–120 × 1.5–9 mm, bases cuneate to slightly attenuate;

distal (ascending or spreading) sessile, blades oblong or linear-lanceolate to linear, 2–45 × 0.5–4 mm, reduced distally (abruptly on branches), bases cuneate to rounded, not clasping, margins entire or serrate.

Peduncles

0.6–4 (–6) cm, bracts 2–8, awl-shaped, grading into phyllaries.

slender, usually stiff (sometimes lax), (0.5–)1–5 cm (rarely subsessile), progressively reduced distally, usually not secund, sparsely strigillose or glabrous, bracts 5–16+, spreading to ascending, linear-oblong or -elliptic to subulate or linear, progressively reduced distally, grading into phyllaries.

Involucres

narrowly turbinate, 4.1–9.5(–11) mm.

cylindro-campanulate, (3–)4.5–6.3 mm.

Ray florets

10–25;

corollas white or pink, laminae (4.5–)5–8.5(–9.5) × 1.2–2 mm.

15–33;

corollas pale blue, pink, or lavender to white, laminae (4–)5–7(–8) × 1–1.7 mm.

Disc florets

25–45(–54);

corollas yellow becoming purplish, 3.4–6(–6.8) mm, tubes shorter than to equaling the narrowly funnelform throats (sparsely hairy at base), lobes ± erect, narrowly triangular, 0.5–0.8 mm.

15–30;

corollas cream to pale yellow turning pink, 3.5–4.5 mm, tubes shorter than to equal to narrowly funnelform throats, lobes lanceolate, (0.4–)0.6–1.1 mm.

Phyllaries

in 4–5 series, lanceolate to subulate, bases indurate, rounded, margins hyaline, often tinged with purple, entire, green zones spatulate to oblanceolate-rhombic, apices acute, adaxial faces glabrous or minutely hairy distally.

in 4–6 series, appressed or slightly spreading, oblong-oblanceolate (outer) to linear-oblanceolate or linear (innermost), strongly unequal, bases indurate (1/2–)2/3–4/5, margins hyaline, scarious, erose, distally ciliolate, green zones oblanceolate to elliptic (subapical), apices acute to obtuse (scarious), sometimes faintly reddish, mucronulate, faces usually glabrous, sometimes glabrate.

Heads

(1–)3–20(–40), in open, diffuse, paniculiform arrays, branches patent.

in remote, diffuse, open, paniculiform arrays, branches numerous, ascending to stiffly ascending, secondary ones stiff, racemiform (usually not secund).

Cypselae

light brown, narrowly obovoid to fusiform, sometimes ± compressed, 1.5–4(–4.5) mm, 5–6-nerved, faces sparsely strigillose;

pappi tawny to white, 3–6.1 mm.

pink or stramineous with pink streaks, or gray (± dark, nerves stramineous), oblong-obovoid, sometimes ± compressed, 1.5–2.5 mm, 3–4-nerved (nerves prominent), faces strigillose;

pappi white to sordid, 4 mm.

2n

= 16, 32.

Symphyotrichum tenuifolium

Symphyotrichum dumosum

Phenology Flowering Aug–Oct.
Habitat Open or wooded, moist or wet soils, bogs, fens, sedge meadows, marshes, swamps, flood plains, sandy or calcareous flats, loamy prairies, old fields, sandhills, flatwoods, hammocks, pine-hickory woods, oak or pine thickets, secondary woods, sandy to mucky or marly shores of lakes and ponds, interdunal hollows
Elevation 0–700 m (0–2300 ft)
Distribution
from FNA
AL; CT; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; RI; SC; TX; VA; West Indies
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KY; LA; MA; MD; ME; MI; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; WI; WV; NB; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Along the Gulf of Mexico Coast in central and northern peninsular Florida, vars. tenuifolium and aphyllum intergrade in nearly all characters (S. D. Sundberg 2004). G. L. Nesom (2005d) treated the varieties as species.

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

Symphyotrichum dumosum is introduced in New Brunswick. It is widely cultivated. It can hybridize with S. racemosum and S. lanceolatum var. interior (A. G. Jones 1989). G. L. Nesom (1994b) and J. C. Semple et al. (2002) recognized several varieties within the complex: var. dumosum [syn. Aster coridifolius Michaux, A. dumosus Linnaeus var. coridifolius (Michaux) Torrey & A. Gray]; var. gracilipes (Wiegand) G. L. Nesom (syn. A. dumosus var. gracilipes Wiegand); var. pergracile (Wiegand) G. L. Nesom (syn. A. dumosus var. pergracile Wiegand); var. strictior (Torrey & A. Gray) G. L. Nesom [syn. A. dumosus var. strictior Torrey & A. Gray, A. dumosus var. dodgei Fernald, S. dumosum var. dodgei (Fernald) G. L. Nesom, the latter possibly the hybrid S. dumosum × S. boreale fide G. L. Nesom 1997]; and var. subulifolium (Torrey & A. Gray) G. L. Nesom (syn. A. dumosus var. subulifolium Torrey & A. Gray). Some of these taxa may deserve higher rank. More work is needed in the complex, however, before a coherent taxonomy can be achieved.

G. L. Nesom (1997) recognized also a southern pine flatwoods entity called Symphyotrichum kralii G. L. Nesom, based on the illegitimately named Aster pinifolius Alexander (not Nees, nor F. Mueller). The type of A. pinifolius, however, appears to be conspecific with that of S. simmondsii. At present, it seems best to wait for full investigation before formally recognizing such taxa.

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

Key
1. Stems 1, rhizomes long; mid leaves (1.5–)3–6 mm wide; involucres 6–9.5(–11) mm; ray florets (12–)17–25; disc florets 25–45(–54), corollas (4–)4.7–6(–6.5) mm; cypselae 2.8–4(–4.5) mm; pappi 5–6.1 mm
var. tenuifolium
1. Stems 1–5+ (clustered), rhizomes short; mid leaves (1–)1.5–2.7 mm wide; involucres 4.1–5.3 mm; ray florets 10–16; disc florets (10–)13–23, corollas 3.4–4.6 mm; cypselae 1.5–2(–2.5) mm; pappi 3–4.4 mm
var. aphyllum
Source FNA vol. 20, p. 479. FNA vol. 20, p. 514.
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. subulatum, 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. 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. urophyllum, S. walteri, S. welshii, S. yukonense, S. ×amethystinum
Subordinate taxa
S. tenuifolium var. aphyllum, S. tenuifolium var. tenuifolium
Synonyms Aster tenuifolius Aster dumosus, Aster coridifolius
Name authority (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) (Linnaeus) G. L. Nesom: Phytologia 77: 280. (1995)
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