Symphyotrichum ericoides |
Symphyotrichum oblongifolium |
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aster éricoïde, heath American-aster, heath-leaf aster, little gray aster, rayless alkali aster, tuft white prairie aster, white heath aster |
aromatic aster, oblong-leaf aster |
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Habit | Perennials, 20–80(–100) cm, colonial or cespitose, eglandular; branched rhizomatous, or with ± cormoid, branched, woody caudices. | Perennials, 10–80(–100) cm, colonial; with thick, woody, short-branched caudices, sometimes ± cormoid, and thin, woody rhizomes. | ||||
Stems | 1–3+, ascending to erect (grayish brown to brown), sparsely to densely hispido-strigose, sometimes glabrescent proximally. |
1–10+, ascending to erect or decumbent, light to dark brown, proximally glabrous, distally hispiduloso-hirsute or hirtellous, stipitate-glandular. |
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Leaves | usually all except rameal withered by flowering, (light grayish green) firm apices ± white-spine-tipped (often with clusters of smaller leaves in axils); basal sessile, blades (3-nerved) oblanceolate to oblong or spatulate, 10–50 × 10–25 mm, bases attenuate, margins usually entire, rarely remotely serrate, scabrous, apices rounded to obtuse, faces usually sparsely hairy, often glabrous; proximal cauline sessile, blades (1- or 3-nerved) linear to lanceolate or oblong, 10–40(–60) × 1.5–4(–7) mm, reduced distally, bases cuneate, coarsely ciliate, margins entire, coarsely ciliate, apices acute or obtuse, faces moderately to densely strigose or hirsute; distal sessile, blades oblong-ovate, 10–40 × 1.5–3.5 mm, abruptly reduced distally, bases cuneate, margins entire, apices acute, faces moderately to densely strigose. |
(yellowish to dark green) thin, margins entire; basal sometimes persistent, sessile, blades (3-nerved) oblanceolate to spatulate, 20–50(–70) × 5–15 mm, margins entire (remotely serrate), coarsely ciliate, apices rounded, short-mucronate, faces usually hirsute, rarely glabrous, often also stipitate-glandular; proximal cauline sessile (often with clusters of smaller leaves in axils), blades oblong or linear-lanceolate, (15–)30–100 × 5–15(–20) mm, bases rounded or slightly clasping, margins scabrellous, apices acute to obtuse, spinulose-mucronate, abaxial faces scabrous, often stipitate-glandular, adaxial hirsute; distal sessile, blades lanceolate to oblong, 20–80 × 2–10(–20) mm, greatly reduced distally, bases cuneate to subclasping, margins ciliate, stipitate-glandular, apices acute to obtuse, white-mucronate, faces moderately strigose, moderately to densely stipitate-glandular. |
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Peduncles | 0.5–1(–2) cm or subsessile, densely hairy, bracts dense, linear to narrowly lanceolate, usually reflexed, sometime appressed to ascending, 1.5–5(–6) mm, densely hairy, grading into phyllaries. |
0.5–5 cm, hispid, stipitate-glandular, bracts dense, spreading or squarrose (rarely ascending), linear to narrowly oblong, 3–8 mm, grading into phyllaries, spinulose, short-strigose. |
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Involucres | cylindric to campanulate, 2.5–4.5(–5) mm. |
campanulate, (5–)7–9 mm. |
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Ray florets | (8–)10–18(–20); corollas usually white, rarely pink or bluish, laminae 6–12(–20) × 0.7–1.2 mm. |
(10–)25–35; corollas light to dark rose-purple, lavender to deep purple, laminae 9–13(–15) × 1–2 mm. |
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Disc florets | 6–12(–20); corollas yellow becoming brown, 2.5–4 mm, throats narrowly funnelform, lobes triangular, 0.5–0.6 mm, glabrous. |
(25–)30–40(–50); corollas yellow turning brown or reddish purple, 4.5–5.5(–6) mm, tubes 1/2 the funnelform to nearly tubular throats, lobes triangular, 0.4–0.7 mm. |
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Phyllaries | in 3–4 series, oblanceolate to ± spatulate, unequal, firm, bases (whitish to tan) ± indurate in proximal 1/2–2/3, margins hyaline, scabrous proximally, green zones diamond-shaped, in distal 1/2, apices spine-tipped, (outer) spreading to reflexed or squarrose, faces (outer) sparsely to densely hispid, scabroso-hirsute adaxially, (inner) glabrous. |
in 4–5(–6) series, outer oblanceolate, mid linear-lanceolate, inner linear, usually unequal, sometimes subequal, bases ± indurate, margins hyaline, scarious, erose, ciliate or ciliolate and/or stipitate-glandular, green zones often broadly foliaceous (outer), green in distal 1/3–1/2 (mid), apices spreading to reflexed (outer), acute, mid long-acuminate, faces moderately hairy, stipitate-glandular. |
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Heads | (1–200+) in paniculiform arrays, branches fastigiate or arrays often pyramidal, racemiform, secund, crowded. |
in ample, corymbiform to diffusely paniculiform arrays, branches initially patent, then ascending (often from proximal nodes). |
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Cypselae | deep purple turning brown, obovoid to oblong-obovoid, ± falcate, not compressed, 1.2–2 × 0.4–0.6 mm, 7–9-nerved (faint), faces sericeous or densely strigillose; pappi whitish, 3–4 mm. |
dull purple or brown (nerves stramineous), obovoid, slightly falcate, not compressed, 2–2.5 mm, 7–10-nerved, faces sparsely strigillose or sericeous; pappi tawny (barb tips sometimes rose-tinged), 3.5–6 mm. |
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2n | = 10, 20. |
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Symphyotrichum ericoides |
Symphyotrichum oblongifolium |
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Phenology | Flowering Aug–Nov. | |||||
Habitat | Open, dry, rocky, sandy, gravelly, or shaly soils, limestone glades and outcrops, sandstone or calcareous cliffs, open-wooded bluffs, prairies, pastures, dunes, roadsides | |||||
Elevation | 100–1500+ m (300–4900+ ft) | |||||
Distribution |
AR; AZ; CO; CT; DC; DE; IA; ID; IL; IN; KS; MA; MD; ME; MI; MN; MO; MS; MT; ND; NE; NJ; NM; NY; OH; OK; OR; PA; RI; SD; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NT; ON; QC; SK; n Mexico
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AL; AR; CO; IA; IL; IN; KS; KY; MD; MN; MO; MS; MT; NC; ND; NE; NM; OH; OK; PA; SD; TN; TX; VA; WI; WV; WY; Mexico (Coahuila)
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Discussion | Varieties 2 (2 in the flora). Symphyotrichum ericoides resembles S. pilosum var. pilosum, which has larger heads, longer rays, and phyllaries that are not spine-tipped, though the revolute margins can make them appear so. Two subspecies and four weakly separated varieties of S. ericoides were recognized by A. G. Jones (1978). Tetraploids of var. ericoides on the eastern prairies can be difficult to distinguish from S. falcatum. A number of aster cultivars are sold under the name “Aster ericoides.” These are all derived from European garden plants and are either cultivars of S. dumosum, S. lateriflorum, S. pilosum, or S. racemosum, or hybrids involving one of those species and another taxon. The misapplication of the epithet ericoides dates back to the nineteenth century and has persisted in the horticultural literature. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Symphyotrichum oblongifolium varies greatly in leaf size and shape, the extremes of which have been the bases for varieties that are not distinct but merely represent the ends of a continuum of variation. The species is similar to S. ×amethystinum (S. ericoides × S. novae-angliae), but the latter has more hairy stems and leaves, and eglandular phyllaries. A leafy cultivar of the species is offered in the horticulture trade. A form with pink rays, merely a population variation, has been recognized as distinct from the more purple typical form: Aster oblongifolius forma roseoligulatus Shinners. Symphyotrichum batesii (Rydberg) G. L. Nesom (syn. Aster batesii Rydberg), reported from Nebraska, is the intersectional hybrid of this species with S. ericoides var. ericoides. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 494. | FNA vol. 20, p. 486. | ||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus | Asteraceae > tribe Astereae > Symphyotrichum > subg. Virgulus | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Aster ericoides, Lasallea ericoides, Virgulus ericoides | Aster oblongifolius, Virgulus oblongifolius | ||||
Name authority | (Linnaeus) G. L. Nesom: Phytologia 77: 280. (1995) | (Nuttall) G. L. Nesom: Phytologia 77: 287. (1995) | ||||
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