Symphyotrichum tenuifolium |
Symphyotrichum subspicatum |
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perennial saltmarsh American-aster, perennial saltmarsh aster |
Douglas' aster |
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Habit | Perennials, (20–)40–60(–100) cm, colonial or cespitose; rhizoma-tous. | Perennials, 40–120 cm, colonial; long-rhizomatous. | ||||
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+, ascending to erect, proximally glabrous, distally usually glabrous or sparsely puberulent, rarely densely hirsute. |
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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 entire or often serrate, apices acute, faces glabrous or sparsely puberulent; basal withering by flowering, petiolate to subpetiolate, blades oblanceolate to narrowly elliptic or linear, 50–150 × 3–25 mm, bases attenuate, margins entire or sometimes serrate, apices acute; proximalmost cauline withering by flowering, subpetiolate or sessile, blades obovate or oblanceolate to narrowly elliptic, rarely linear, 50–150 × 4–35 mm, bases attenuate or cuneate; distal sessile, blades 30–100(–130) × 3–15(–30) mm, bases cuneate, rounded or sometimes ± auriculate, margins sometimes serrate, scabrous. |
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Peduncles | 0.6–4 (–6) cm, bracts 2–8, awl-shaped, grading into phyllaries. |
sparsely hairy, bracts 1–10, lance-oblong to linear, sometimes clasping, margins scabrous. |
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Involucres | narrowly turbinate, 4.1–9.5(–11) mm. |
campanulate, 5–8(–10) mm. |
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Ray florets | 10–25; corollas white or pink, laminae (4.5–)5–8.5(–9.5) × 1.2–2 mm. |
15–45; corollas violet, laminae 10–16(–20) × (1–)1.5–2.5 mm. |
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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. |
50–75; corollas yellow becoming reddish, 4–7 mm, lobes triangular, 0.5–1 mm, glabrous. |
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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 squarrose, oblong or narrowly oblanceolate or linear (outer) to linear (inner), unequal to subequal (outer shorter than or equal to inner, often less than 3 times as long as wide), bases outer indurate less than 1/2 (some foliaceous), inner scarious, margins entire, sometimes ciliate, green zones obovate to elliptic, apices acute to obtuse, faces usually glabrous, rarely sparsely puberulent. |
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Heads | (1–)3–20(–40), in open, diffuse, paniculiform arrays, branches patent. |
in open, corymbiform, paniculiform, or racemiform arrays, branches 5–30 cm. |
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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. |
brown or purplish, cylindric to obovoid, not compressed, 2–4 mm, 3–6-nerved, faces hairy; pappi whitish to tawny or reddish, 4.5–8 mm. |
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2n | = 48, 64, 80, 96. |
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Symphyotrichum tenuifolium |
Symphyotrichum subspicatum |
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Phenology | Flowering Jul–Sep. | |||||
Habitat | Marshes, thickets, weedy meadows, open disturbed habitats | |||||
Elevation | 0–1000 m (0–3300 ft) | |||||
Distribution |
AL; CT; DE; FL; GA; LA; MA; MD; ME; MS; NC; NH; NJ; NY; RI; SC; TX; VA; West Indies
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AK; CA; ID; MT; OR; WA; AB; BC
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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 subspicatum is a weedy, highly polyploid species, probably of allopolyploid derivation from different combinations of species including S. chilense, S. bracteolatum, S. foliaceum, S. laeve, and S. spathulatum. Hybrids with S. hallii are known from western Oregon. The species passes into S. foliaceum in southeastern Alaska. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 479. | FNA vol. 20, p. 537. | ||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Aster tenuifolius | Aster subspicatus, Aster butleri, Aster maccallae, Aster subspicatus var. grayi | ||||
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 293. (1995) | (Nees) G. L. Nesom: Phytologia 77: 293. (1995) | ||||
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