Symphyotrichum novae-angliae |
Symphyotrichum prenanthoides |
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aster de nouvelle-angleterre, New England American-aster, New England aster, New England or michaelmas daisy |
crooked-stem American-aster, crookedstem aster |
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Habit | Perennials, 30–120 cm, cespitose; with thick, woody, branched caudices, or short, fleshy rhizomes, sometimes with woody cormoid portions. | Perennials, 20–90(–120) cm, colonial; long-rhizomatous. |
Stems | 1–5+, erect (stout, light to dark brown, sometimes purplish distally), proximally sparsely to moderately hispiduloso-hirsute or pilose, distally moderately to densely so, stipitate-glandular. |
1(–3+), ascending to erect (usually flexuous, sometimes ± straight, sometimes stout, older often dark purple), glabrous proximally, moderately hirsute distally. |
Leaves | (light to dark green) thin, often stiff, margins entire or sometimes with shallow teeth, ciliate; basal withered or withering by flowering, sessile, blades (3-nerved) usually spatulate, sometimes oblanceolate, 20–60 × 5–15 mm, bases attenuate, apices acute, faces sparsely hirsute; proximal cauline withering by flowering, sessile, blades oblong or lanceolate, 50–100 × 5–15(–20) mm, bases auriculate-clasping, margins entire, pustulate-scabrous, apices acute, mucronulate, faces stipitate-glandular, abaxial thinly strigose, adaxial hirsute or hispidulous; distal sessile, blades oblanceolate, 30–80 × 6–15 mm, gradually reduced distally, bases auriculate-clasping, apices acute to obtuse, mucronate to minutely white-spinulose, faces moderately to densely short-soft-hairy, sparsely to moderately stipitate-glandular. |
thin, margins scabrous, apices mucronate, abaxial faces glabrous, midveins hispid to glabrate, adaxial scabrous; basal withering by flowering, petiolate (petioles slender or slightly winged, bases reddish, dilated, sheathing, ciliate), blades obovate to oblanceolate, 15–70 × 10–20 mm, bases attenuate, margins crenate-serrate, apices acute to obtuse; proximalmost cauline withering by flowering, proximal mostly persistent, petiolate to subpetiolate (petioles ± widely winged, bases dilated, strongly auriculate-clasping), blades ovate to lance-ovate or elliptic-lanceolate to oblanceolate, 80–160(–200) × 15–55 mm, progressively reduced distally, bases attenuate, margins sharply serrate (teeth mucronulate), apices acuminate to subcaudate; distal subpetiolate or sessile (petioles broadly winged, auriculate-clasping), blades oblanceolate to lanceolate, sometimes panduriform, 7–90 × 2–25 mm, progressively reduced distally, more sharply so on branches, bases attenuate (petiolate) or ± cuneate to auriculate-clasping and slightly constricted above auricles (panduriform), margins serrate or entire. |
Peduncles | dilated distally, 0.3–4 cm, densely short-hairy, stipitate-glandular, bracts 1–4, foliaceous, linear to narrowly lanceolate, densely short-hairy, stipitate-glandular, grading into phyllaries. |
(8–)10–40 mm, sparsely to densely hispid, bracts lanceolate to linear-lanceolate, 3–12 mm, somewhat grading into phyllaries. |
Involucres | campanulate to hemispheric, (5–)7–9(–15) mm. |
campanulate, 5–6 mm. |
Ray florets | (40–)50–75(-100); corollas dark rose to deep purple (pale pink or white), laminae 9–13 × 0.8–1.3 mm. |
17–25(–30); corollas usually lavender to blue, rarely white, laminae 7.5–12(–15) × 1–2 mm. |
Disc florets | 50–110; corollas light yellow becoming purple, (4–)4.5–5.5(–7) mm, tubes ± 1/2 narrowly funnelform throats (glabrous or thinly puberulent), lobes triangular, 0.4–0.7 mm. |
39–50(–65); corollas cream colored or light yellow becoming purple or brown, 3.5–5 mm, tubes ± equaling campanulate to funnelform throats (thinly puberulent), lobes triangular, 0.5–1 mm. |
Phyllaries | in 3–5(–6) series (dark green to purple-tinged), linear-lanceolate, subequal, outer foliaceous, mid and inner scarious in basal 1/3–1/2, margins stipitate-glandular, apices long-acuminate to acuminate, spreading to reflexed or squarrose, faces glabrous, outer densely stipitate-glandular. |
in 4–6 series, oblong-lanceolate or -oblanceolate, slightly constricted near middle (outer) to linear-lanceolate or linear (inner), ± unequal (flexible), bases indurate 1/5–1/2, margins ± narrowly hyaline, scarious, erose, sometimes ciliolate distally, green zones lanceolate to linear-lanceolate (inner), often distally foliaceous, sometimes outer ± entirely so, apices spreading to ± squarrose, acute to acuminate, mucronulate, abaxial faces sparsely hirsutulous to glabrate or glabrous, adaxial glabrous or sparsely hirsutulous. |
Heads | in leafy, often crowded, paniculo-corymbiform arrays. |
in broad, ± flat, corymbo-paniculiform arrays, branches often purplish, divaricate to ascending, slender. |
Cypselae | dull purple or brown, oblong or obconic, not compressed, 1.8–2.5(–3) × 0.6–1 mm, 7–10-nerved, faces densely sericeous, sparsely stipitate-glandular; pappi tawny (barb tips sometimes rose-tinged), 4.5–6 mm. |
dull purple or stramineous with purple streaks or purplish-tinged, cylindro-oblanceoloid to obovoid, ± compressed, 2–3(–3.5) mm, 4–6-nerved, faces sparsely to moderately strigillose; pappi sordid, 3.5–4.5 mm. |
2n | = 10. |
= 32. |
Symphyotrichum novae-angliae |
Symphyotrichum prenanthoides |
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Phenology | Flowering Aug–Oct(–Nov). | Flowering Aug–Oct. |
Habitat | Open, moist to wet, sandy or loamy, rich soils, fields, prairies, meadows, marshy grounds, shrubby swamps, fens, shores, thickets, moist edges of woods, roadsides, railroad rights-of-way, somewhat weedy | Moist or swampy grounds, woods, thickets, meadows, seeps, stream banks, roadsides |
Elevation | 0–1600 m (0–5200 ft) | 100–1500 m (300–4900 ft) |
Distribution |
AL; AR; CO; CT; DC; DE; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; SD; TN; UT; VA; WA; WI; WV; WY; MB; NB; NS; ON; QC [Introduced in Europe]
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CT; DC; DE; IA; IL; IN; KY; MA; MD; MI; MN; NC; NJ; NY; OH; PA; VA; WI; WV; ON
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Discussion | Symphyotrichum novae-angliae is escaped from cultivation and introduced in Montana, Oregon, Utah, Washington, and Wyoming, and has been reported as an ephemeral escape in British Columbia. It possibly escaped from cultivation elsewhere. The Michaelmas daisy is widely sold in the horticultural trade, where cultivars have been developed. Forms have been described that correspond to color genetic variants within natural populations {Aster novae-angliae forma roseus (Desfontaines) Britton; A. novae-angliae forma geneseensis House}; they are not recognized here. Symphyotrichum novae-angliae resembles Canadanthus modestus, but the ranges of the two do not overlap, and the latter has sparsely hairy cypselae with dark ribs. Symphyotrichum novae-angliae hybridizes with S. ericoides, forming the F1 intersectional hybrid S. ×amethystinum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Symphyotrichum prenanthoides is of conservation concern in Canada and in a number of states. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 487. | FNA vol. 20, p. 527. |
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus | Asteraceae > tribe Astereae > Symphyotrichum > subg. Symphyotrichum > sect. Symphyotrichum |
Sibling taxa | ||
Synonyms | Aster novae-angliae, Virgulus novae-angliae | Aster prenanthoides |
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 287. (1995) | (Muhlenberg ex Willdenow) G. L. Nesom: Phytologia 77: 290. (1995) |
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