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perennial saltmarsh American-aster, perennial saltmarsh aster

smallhead aster, smallhead or small white aster

Habit Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. Perennials (sometimes short-lived), 30–100 cm, colonial or cespitose; long-rhizomatous or with short, branched 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.

1–3+, ascending to erect (straight, slender, reddish), sparsely to densely pilosulous to hirtellous, proximally glabrescent.

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.

thin, margins strigoso-ciliate to scabrous, apices mucronulate, abaxial faces glabrate to sparsely pilose and midveins ± pilose to glabrate, adaxial glabrous or glabrate to pilosulous or hirsutulous;

basal withering by flowering, subpetiolate, blades oblanceolate to narrowly oblanceolate or spatulate, 10–40 × 3–7 mm, bases cuneate, sheathing, margins sparsely serrate apically, apices obtuse, mucronate, faces sparsely pilose;

proximal cauline usually withering by flowering, sessile or subsessile (often with axillary clusters of small leaves), blades oblanceolate to lanceolate, 40–80 × 2–5 mm, bases cuneate, margins entire or serrulate apically;

distal sessile, blades linear to subulate, 4–100 × 1–6 mm, reduced distally, bases cuneate, margins entire to weakly serrulate, faces glabrate or glabrous.

Peduncles

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

3–20(–40) mm, glabrate or glabrous, bracts 3–6+, appressed or ascending, linear to subulate, 2–4 mm, scabrous, aristate, glabrous, grading into phyllaries.

Involucres

narrowly turbinate, 4.1–9.5(–11) mm.

cylindric to cylindro-campanulate, (2.7–)3.1–4.1(–4.9) × ± 3 mm.

Ray florets

10–25;

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

(9–)11–17(–23);

corollas usually white, seldom pink, laminae (3.7–)5–5.5(–7.3) × 0.6–1.3 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.

5–16(–28);

corollas pale yellow becoming purplish, (2.3–)2.5–3.3(–3.7) mm, tubes shorter than narrowly funnelform throats, lobes lanceolate, 0.4–0.8 (ratio 0.25) 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 3–5 series, appressed, subulate (outermost) to oblong-lanceolate to linear-lanceolate (inner) or linear (innermost), unequal, bases indurate 1/2–3/4, margins scarious, erose, hyaline, sparsely ciliolate or not, green zones lanceolate, apices slightly spreading, often purplish, often involute, acute to acuminate or cuspidate, sometimes aristate, faces usually glabrous, sometimes glabrate.

Heads

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

in narrow or wide, pyramidal, paniculiform arrays, branches ascending or arching, secondary branches (10 cm or less) secund and erect, densely leafy, heads crowded, sparsely to moderately pilose.

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.

whitish or gray, obovoid, compressed, 0.8–1.5 × 0.4–0.6 mm, 3–4-nerved, faces sparsely to moderately strigillose;

pappi white, 3–4 mm.

2n

= 16, 32, 48.

Symphyotrichum tenuifolium

Symphyotrichum parviceps

Phenology Flowering Aug–Oct.
Habitat Open, dry, sandy, or loamy soils, open woods, barrens, prairies, fields, roadsides, old cemeteries
Elevation 200–400 m (700–1300 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
AR; IA; IL; KS; MO; OK
[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.)

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. 511.
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. 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. 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 ericoides var. parviceps, Aster parviceps, Aster pilosus subsp. parviceps
Name authority (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) (E. S. Burgess) G. L. Nesom: Phytologia 77: 288. (1995)
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