Symphyotrichum novae-angliae |
Symphyotrichum sericeum |
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aster de nouvelle-angleterre, New England American-aster, New England aster, New England or michaelmas daisy |
silky aster, western silver aster, western silvery 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–)30–70 cm, cespitose, eglandular; with short, woody, cormoid caudices, or short rhizomes. |
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. |
1–5+, ascending to erect (thin, grayish brown to dark brown), glabrous proximally, densely canescent 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. |
(silvery) firm, soft; basal withering by flowering, sessile, blades (1–3 nerved) elliptic-lanceolate, 10–40 × 5–15 mm, bases cuneate, weakly sheathing, margins usually entire, rarely remotely serrate, piloso-ciliate, apices acute, faces less copiously hairy than cauline; proximal cauline withering by flowering, sessile, blades oblanceolate or oblong to linear-lanceolate, 15–30(–50) × 4–10 mm, slightly and progressively reduced distally, bases rounded, subclasping, margins entire, silky-pilose, apices obtuse to acute, mucronulate, faces sparsely to densely silky-pilose; distal sessile, blades lanceolate, 10–30 × 5–8 mm, little reduced distally, bases cuneate, margins entire, apices acute, mucronate, faces ± densely silky. |
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. |
subsessile or 0.5–3(–5) cm, densely sericeo-strigose, bracts crowded, 4–8(–10) mm, grading into phyllaries. |
Involucres | campanulate to hemispheric, (5–)7–9(–15) mm. |
campanulate to cylindric, (5–)7.5–10 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. |
(10–)15–30; corollas usually rose-purple to deep purple, rarely white, laminae 8.5–11 × 1–1.5 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. |
(15–)25–35; corollas pink turning purple, (5–)5.5–7 mm, tubes shorter than narrowly funnelform throats (both thinly puberulent), lobes deltate, 0.7–0.9 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 3–5(–6) series, outer ovate with expanded distal portion [(4–)5–6 mm], mid ovate-lanceolate [6–8(–10) mm] with expanded green portions, inner linear, unequal or sometimes subequal, outer often foliaceous, bases (mid) scarious, margins silky, green zones restricted to expanded distal 1/2–2/3 (obscured by hairs), apices (outer) spreading or squarrose to reflexed, acute, mucronulate, faces densely long-silky. |
Heads | in leafy, often crowded, paniculo-corymbiform arrays. |
in open, paniculiform arrays, branches sparse, fastigiate, often arching (1–5+ per branch). |
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. |
purple or brown, obovoid, not compressed, 2–3 mm, 7–10-nerved (prominent), faces glabrous; pappi whitish or tawny, 6–7 mm. |
2n | = 10. |
= 10, 20. |
Symphyotrichum novae-angliae |
Symphyotrichum sericeum |
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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 | Open, dry, deep, sandy or loamy soils, broken limestone outcrops, open-wooded bluffs, open woods, open calcareous hammocks, prairies, fields, sand barrens, dunes, dry banks, rarely acidic shield rocks |
Elevation | 0–1600 m (0–5200 ft) | 100–500+ m (300–1600+ 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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AR; GA; IA; IL; IN; KS; MI; MN; MO; ND; NE; OH; OK; SD; TN; TX; WI; MB; ON; West Indies (Bahamas)
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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 sericeum is known in the Bahamas as S. lucayanum (Britton) G. L. Nesom [syn. Aster lucayanus Britton, Virgulus lucayanus (Britton) Reveal & Keener]. It is of conservation concern in Indiana, Michigan, and Canada. Symphyotrichum sericeum is distinct and unlikely to be confused with other species due to its silvery-silky leaves and phyllaries, open arrays, and cormoid rootstocks. Aster sericeus forma albiligulatus Fassett is a white form of the species, in contrast to the typically purple forma sericeus; these do not deserve formal recognition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 487. | FNA vol. 20, p. 494. |
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus |
Sibling taxa | ||
Synonyms | Aster novae-angliae, Virgulus novae-angliae | Aster sericeus, Lasallea sericea, Virgulus sericeus |
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 287. (1995) | (Ventenat) G. L. Nesom: Phytologia 77: 291. (1995) |
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