Symphyotrichum subulatum |
Symphyotrichum welshii |
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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 |
Welsh's aster |
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Habit | Annuals, (10–)30–150 cm; tap-rooted. | Perennials, 30–100 cm colonial; rhizomes shallow and long, often relatively thick (those of the season each producing a distal rosette near the parent plant). | ||||||||||||||||
Stems | 1, erect (often with purple or purplish brown areas), glabrous or glabrate, sometimes strigillose in leaf axils. |
1–2, ascending to erect (sometimes lax, sometimes reddish), glabrous or sparsely strigoso-villosulous distally (arrays). |
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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. |
(adaxially green, abaxially pale green, sometimes glaucous) thin (proximal) to stiff (distal), margins serrulate (proximal) or entire or nearly so, ± revolute, scabrous, apices mucronulate or sometimes callous-pointed, faces glabrous; basal withering by flowering, petiolate (petioles narrowly winged, sheathing), blades oblanceolate to spatulate, 10–40+ × 4–9+ mm, bases attenuate, margins entire, apices obtuse; proximal cauline withering by flowering, sessile or winged-petiolate, blades lanceolate to oblanceolate, 50–150 × 8–11 mm, bases slightly clasping, margins sparsely serrulate, apices acute; distal sessile, blades linear to linear-lanceolate, 50–130 × 4–6 mm, gradually reduced distally, bases ± clasping, apices acute. |
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Peduncles | (0.2–)0.5–4 cm, bracts 4–8(–17). |
0.5–2 cm, scabro-villosulous, bracts linear, scabro-ciliolate. |
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Involucres | cylindric to turbinate, 5–7(–8.2) mm. |
cylindro-campanulate, 4–7 mm. |
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Ray florets | 16–30(–54) in 1–3 series; corollas white, pink, or lavender, laminae 1.3–7 × 0.2–1.3 mm. |
18–25; corollas pink to white, laminae 9–12 × 0.8–1.5 mm. |
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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. |
23–60; corollas pale yellow, 3.8–6.4 mm, tubes shorter than funnelform throats, lobes narrowly triangular, 0.4–0.8 mm. |
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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 series, lanceolate (outer) to linear (inner), ± unequal, bases indurate, margins hyaline, erose, distally scabro-ciliolate to ciliolate, green zones ± foliaceous (outer) or lanceolate, apices acute to acuminate, sometimes purplish, faces glabrous. |
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Heads | (10–) 30–100(–150), in open, diffuse, paniculiform arrays. |
in open, slender, leafy, paniculiform or racemiform arrays, branches ascending. |
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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. |
pinkish tan (nerves stramineous), obovoid, ± compressed, 0.8–1.6 mm, 3–5-nerved, faces sparsely strigillose; pappi white, 2.8–5.3 mm. |
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2n | = 16. |
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Symphyotrichum subulatum |
Symphyotrichum welshii |
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Phenology | Flowering Aug–Oct. | |||||||||||||||||
Habitat | Wet soils in dry areas, hanging gardens, seeps, wet ledges, stream banks | |||||||||||||||||
Elevation | 1300–2300 m (4300–7500 ft) | |||||||||||||||||
Distribution |
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]
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AZ; ID; MT; UT; WY |
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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.) |
Of conservation concern. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 480. | FNA vol. 20, p. 523. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | ||||||||||||||||
Sibling taxa | ||||||||||||||||||
Subordinate taxa | ||||||||||||||||||
Synonyms | Aster subulatus | Aster welshii | ||||||||||||||||
Name authority | (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) | (Cronquist) G. L. Nesom: Phytologia 77: 294. (1995) | ||||||||||||||||
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