Symphyotrichum lanceolatum |
Symphyotrichum subspicatum |
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aster lancéolé, lance-leaf American-aster, lance-leaf aster, lance-leaf or panicle or white panicle aster, marsh aster, panicle aster, tall white aster, western willow aster, white-panicle aster |
Douglas' aster |
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Habit | Perennials, 30–150(–200) cm, colonial; long-rhizomatous (rhizomes usually white, thick, contorted). | Perennials, 40–120 cm, colonial; long-rhizomatous. | ||||||||||||||||
Stems | 1, erect (straight, stout), glabrous or hairy. |
1–5+, ascending to erect, proximally glabrous, distally usually glabrous or sparsely puberulent, rarely densely hirsute. |
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Leaves | thin, scabrous, apices mucronate, abaxial faces glabrous (vein areoles indistinct, elongate), adaxial glabrous or sparsely scabrous (var. hesperium); basal withering by flowering, petiolate to subpetiolate (petioles winged, ciliate, bases dilated, sheathing), blades elliptic-oblanceolate or obovate to suborbiculate, 10–80 × 5–20 mm, cuneate to attenuate, margins crenate-serrate, apices acute to obtuse or rounded; proximal cauline withering by flowering, sessile or subsessile, blades lance-ovate or oblanceolate to linear-lanceolate, (40–)50–150 × (3–)10–20(–35) mm, progressively reduced distally, bases cuneate, ± decurrent, margins serrate, apices acute to acuminate; distal sessile, blades oblanceolate to linear, 30–100(–140) mm, only slightly reduced distally, bases cuneate, margins entire. |
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 | 0.5–5 cm, ± pilose, bracts 1–3(–5), linear-oblanceolate to -lanceolate, foliaceous, ciliate. |
sparsely hairy, bracts 1–10, lance-oblong to linear, sometimes clasping, margins scabrous. |
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Involucres | campanulate to cylindric, 3–8 mm. |
campanulate, 5–8(–10) mm. |
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Ray florets | 16–50; corollas white to pinkish or pale blue-violet, laminae 3–10(–14) × 0.5–1.3 mm. |
15–45; corollas violet, laminae 10–16(–20) × (1–)1.5–2.5 mm. |
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Disc florets | (13–)20–40(–52); corollas yellow becoming purple, 2.8–5.8 mm, tubes shorter than funnelform throats, lobes sometimes ± spreading, triangular, 0.4–1.2 mm. |
50–75; corollas yellow becoming reddish, 4–7 mm, lobes triangular, 0.5–1 mm, glabrous. |
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Phyllaries | in (3–)4–6 series, appressed or slightly spreading, linear-lanceolate to linear (innermost), sometimes slightly dilated distally, ± strongly unequal to subequal (var. hesperium), bases indurate 1/4–1/2, margins scarious, erose, hyaline, sparsely ciliolate, green zones lanceolate to linear-lanceolate, outer sometimes foliaceous (particularly var. hesperium), apices acute to acuminate (outer) or acuminate to caudate (inner), mostly mucronulate, abaxial faces glabrous, adaxial sparsely strigillose. |
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 | in ample or diffuse to narrow, elongate, leafy, paniculiform arrays, branches ± ascending, rarely secund, branch leaves often longer than pedicels. |
in open, corymbiform, paniculiform, or racemiform arrays, branches 5–30 cm. |
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Cypselae | gray or tan, obovoid, ± compressed, 1.5–2 mm, 4–5-nerved, faces sparsely strigillose; pappi white to sordid or tawny, 5.5–6 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 lanceolatum |
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; AR; AZ; CA; CO; CT; DC; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK [Introduced in Europe]
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AK; CA; ID; MT; OR; WA; AB; BC
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Discussion | Varieties 5 (5 in the flora). Varieties of Symphyotrichum lanceolatum are sometimes grouped into two subspecies: subsp. hesperium (var. hesperium) and subsp. lanceolatum (the other four varieties). J. C. Semple and J. G. Chmielewski (1987) provided maps of the five taxa. The ranges of var. hesperium and var. lanceolatum overlap in the prairies and in the boreal zone from Alberta to the Clay Belt of northern Ontario. The ranges of the other three varieties do not overlap with that of var. hesperium, but they all overlap each other and with var. lanceolatum in the Midwest. The ecology and cytogeography of the species were summarized by Chmielewski and Semple (2001). The name Aster tradescantii has sometimes been misapplied to this 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. | FNA vol. 20, p. 537. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Occidentales | ||||||||||||||||
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Synonyms | Aster lanceolatus | Aster subspicatus, Aster butleri, Aster maccallae, Aster subspicatus var. grayi | ||||||||||||||||
Name authority | (Willdenow) G. L. Nesom: Phytologia 77: 284. (1995) | (Nees) G. L. Nesom: Phytologia 77: 293. (1995) | ||||||||||||||||
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