Symphyotrichum subulatum |
Symphyotrichum chilense |
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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 |
common California aster, common California or Pacific aster, Pacific aster |
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Habit | Annuals, (10–)30–150 cm; tap-rooted. | Perennials, 40–100(–120) cm, colonial or cespitose; long-rhizomatous. | ||||||||||||||||
Stems | 1, erect (often with purple or purplish brown areas), glabrous or glabrate, sometimes strigillose in leaf axils. |
1–5+, ascending or erect, glabrous or hirsute. |
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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. |
thin, margins entire, apices usually acute, faces glabrous or sparsely puberulent; basal withering by flowering, petiolate, blades (linear-)oblanceolate to obovate, 30–200 × 4–40 mm, bases attenuate, margins entire to finely serrate, apices acute; proximalmost cauline sometimes withering by flowering, sessile, blades broadly to narrowly oblanceolate, 40–150 × 5–30 mm, bases usually ± attenuate or cuneate; distal sessile, blades lanceolate to oblanceolate, 25–90 × 5–30 mm, bases cuneate. |
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Peduncles | (0.2–)0.5–4 cm, bracts 4–8(–17). |
puberulent, bracts 3–10, lanceolate to elliptic, margins often scabrous to ciliolate. |
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Involucres | cylindric to turbinate, 5–7(–8.2) mm. |
campanulate, 5–8 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. |
15–40; corollas violet, laminae 9–15 × 1.5–2.5 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. |
35–60+; corollas yellow, 4–8 mm, lobes triangular, 0.5–1 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 3–5 series, oblanceolate or oblong (outer) to linear (inner), unequal to subequal (outer usually shorter than inner, if so, lengths less than 3 times widths), bases scarious (outer) less than 1/2 or sometimes wholly foliaceous, inner scarious, margins eciliate or ciliolate, green zones oblanceolate to obovate or linear (innermost), apices (outer) obtuse, (inner) acute, faces glabrous or puberulent. |
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Heads | (10–) 30–100(–150), in open, diffuse, paniculiform arrays. |
in open, paniculiform arrays, some branches at least 20+ cm. |
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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. |
brown, cylindric to obovoid, not compressed, 3.5–4.5 mm, 2–4-nerved, faces hairy; pappi white to tawny, 4–8 mm. |
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2n | = 48, 64, 96. |
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Symphyotrichum subulatum |
Symphyotrichum chilense |
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Phenology | Flowering Jul–Sep. | |||||||||||||||||
Habitat | Grasslands, salt marshes, coastal dunes and bluffs, coastal grasslands and scrub, open disturbed habitats in evergreen and Pacific coast coniferous forest | |||||||||||||||||
Elevation | 0–500 m (0–1600 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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CA; OR; WA; BC
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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.) |
Symphyotrichum chilense is restricted to coastal habitats from southwestern British Columbia to central California. It is almost entirely coastal in Oregon, Washington, and southern British Columbia, where it is mainly hexaploid (2n = 48). In Oregon, where it is sympatric with S. subspicatum, the latter is mainly duodecaploid (2n = 96). The distinction does not hold in British Columbia, however, where S. subspicatum is both 2n = 48 and 96, and where S. chilense is less common (G. A. Allen 1984). The species was erroneously thought by Nees to occur in Chile. The plants named Aster chilensis var. medius Jepson are hybrids of S. chilense and S. lentum. (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. 536. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales | ||||||||||||||||
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Synonyms | Aster subulatus | Aster chilensis, Aster chilensis var. invenustus | ||||||||||||||||
Name authority | (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) | (Nees) G. L. Nesom: Phytologia 77: 277. (1995) | ||||||||||||||||
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