Symphyotrichum falcatum
Symphyotrichum nahanniense
Lindley's aster, little gray aster, little grey aster, western heath or white prairie aster, white prairie aster
Nahanni aster
1–5+, ascending to erect (grayish brown to brown), moderately to densely hairy.
1, ascending to decumbent (slender, green to reddish brown), glabrate or sparsely short woolly-pilose in lines or zones, more densely so distally.
(light grayish green) firm, margins entire, strigose, apices ± spine-tipped;
basal withering by flowering, sessile, blades oblanceolate, 10–40 × 3–10 mm, bases attenuate, margins usually entire, rarely remotely serrate, scabrous, apices acute to obtuse, rounded to mucronulate-spinose, faces glabrate to moderately strigose;
proximal cauline sessile, blades linear oblanceolate to oblong, 10–40(–60) × 1.5–4(–7) mm, reduced distally, bases cuneate, margins entire, coarsely ciliate, apices acute or obtuse, faces sparsely to densely appressed hispido-strigose;
distal sessile, blades linear-oblong to linear-lanceolate, 25–45 × 2–3 mm, bases cuneate, margins entire, apices acute, faces moderately to densely strigose.
(light green, abaxial sometimes becoming much darker) thin to firm, margins entire, scabrous, apices mucronulate, faces glabrous;
basal persistent or withering by flowering, petiolate, blades oblanceolate to short-spatulate, 10–130 × 2–8 mm, bases cuneate to attenuate, margins rarely sparsely serrulate, apices obtuse, faces glabrous;
proximal cauline persistent or withering by flowering, sessile, blades oblanceolate to linear lanceolate, 13–60 × 2–6 mm, bases ± clasping, apices acute;
distal sessile, blades linear to linear-lanceolate, 10–36 × 1–4 mm, reduced distally, bases subauriculate, subclasping to ± clasping.
0.2–4 cm, densely hairy, bracts 1–3+, linear to lanceolate, densely hairy.
10–70 mm, sparsely to moderately short-strigose, bracts 0–10, lanceolate, often foliaceous, reduced distally.
campanulate, (4.5–)5–8 mm.
cylindro-campanulate, 4.7–7.4 mm.
(15–)20–35;
corollas usually white, sometimes blue or pink, laminae (8–)18–30 × 1.1–1.4 mm.
15–41;
corollas white to pale rose, often becoming rose-violet, laminae 5–13 × 0.7–1.8 mm.
(8–)18–30;
corollas yellow becoming brown, 2–2.5 mm, lobes triangular, 0.7–1.2 mm, glabrous.
20–60;
corollas yellow turning reddish with age, 3.7–6.6 mm, tubes shorter than funnelform throats, lobes erect to spreading, lanceolate, 0.4–0.8 mm.
in 3–4 series, outer oblanceolate to spatulate (1.5–2 mm), inner linear-lanceolate (3–4 mm), unequal, bases (whitish to tan) ± indurate in basal 1/2–3/4, margins hyaline, scabrous proximally, green zones diamond-shaped, in distal 1/4–1/2, apices (outer) acute to obtuse, clear spine-tipped, spreading to reflexed, (inner) acuminate to attenuate, faces sparsely to moderately hispid-strigose.
in 3–4 series, outer spatulate, inner lanceolate, ± unequal to subequal, bases indurate, margins reddish, papery, erose-ciliate, green zones lanceolate, apices acute, faces glabrous.
[(1–)10–200+] in racemiform to diffuse-paniculiform arrays (1–10+ per branch, usually not crowded).
usually borne singly or in open, paniculiform arrays (sometimes terminating lateral branches arising from decumbent stems or from proximal stem branches), branches few.
dark brown, obovoid, not compressed, 2–2.5 mm, faint-nerved, faces densely strigose;
pappi whitish, 4.5–6 mm.
tan (nerves stramineous), obovoid, compressed, 2–3 mm, 3–5-nerved, faces strigillose;
pappi white, 4–6.5 mm.
= 16.
Symphyotrichum falcatum
Symphyotrichum nahanniense
Varieties 2 (2 in the flora).
Symphyotrichum falcatum is introduced in Ontario and Illinois. It may closely resemble S. ericoides, which has smaller heads with fewer florets in denser arrays. The two can be difficult to distinguish on the Great Plains. A. G. Jones (1978) recognized two subspecies of S. falcatum, one with two varieties. Those two subspecies are treated as varieties here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Of conservation concern.
Symphyotrichum nahanniense is known only from the South Nahanni River (Mackenzie Mountains), Nahanni National Park.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Plants cespitose, 1–5(–10)-stemmed, usually sparsely appressed-strigose, with cormoid caudices; new shoots developing near the bases of old stems; peduncles long, slender, bracts 1–5; phyllaries subequal (outer longest and foliaceous), apices not strongly squarrose | var. falcatum |
1. Plants colonial, usually densely hairy, rhizomes entangled, usually 1-stemmed, sometimes clumped; new shoots developing at ends of elongated rhizomes; peduncles stout, bracts 2–10+; phyllaries ± unequal, apices strongly squarrose | var. commutatum |
BC
IL Wildflowers
KS Wildflowers
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