Symphyotrichum ontarionis
Symphyotrichum oolentangiense
aster du lac Ontario, bottomland aster, Ontario American-aster, Ontario aster
azure aster, skyblue aster
1–(2–3), ascending to erect (straight), proximally glabrate, distally uniformly villous or hirsute, or glabrous (var. glabratum).
1–5+, erect (straight), glabrate to hispidulous, distally pilosulous to strigillose in arrays.
thin, margins scabrous, apices mucronate, abaxial faces usually sparsely to densely strigose or strigillose, sometimes glabrous (var. glabrum), adaxial usually strigose or scabrous, sometimes glabrate or glabrous (var. glabrum);
basal withering by flowering, petiolate to subpetiolate (petioles narrowly winged, ciliate, bases sheathing), blades spatulate to oblanceolate-obovate, 10–40 × 5–10 mm, bases attenuate, margins crenate-serrate, apices acute to rounded;
proximalmost cauline usually withering by flowering, petiolate or sessile (petioles narrowly winged, ± clasping), blades ovate or lance-ovate to elliptic-lanceolate or oblanceolate, 20–80(–12) × 5–35 mm, progressively reduced distally, bases attenuate to cuneate, margins serrate (sometimes coarsely) to crenate-serrate, apices acute to acuminate or short-caudate;
distal sessile, blades elliptic-lanceolate to oblanceolate or lanceolate, (6–)10–80+ × 2–25 mm, progressively reduced distally, bases cuneate, margins entire to serrulate, apices acute to acuminate.
thick, firm, margins entire or crenate-serrate, scabrous, apices mucronate, faces scabrous, abaxial strigose to piloso-strigose or hirsute, adaxial strongly strigose;
basal withering by flowering, long-petiolate (petioles slightly winged, bases dilated, sheathing, ciliate), blades ovate to lance-ovate, 40–150(–180) × 10–40(–60) mm, bases ± cordate or rounded to attenuate, margins crenate-serrate to subentire, apices rounded or obtuse to acute;
proximal cauline petiolate (petioles narrowly winged, clasping), blades ovate or ovate-lanceolate to lanceolate, 30–130 × 12–70 mm, gradually or ± abruptly reduced distally, bases rounded to attenuate, margins entire, scabrous, apices acute or attenuate, callus-pointed;
distal sessile or sometimes short-petiolate and ± winged (appressed or ascending), blades lanceolate or linear-lanceolate to subulate, 5–80 × 1–10 mm, strongly reduced distally (more sharply so on branches), bases attenuate to cuneate or ± rounded, margins entire.
subsessile or 2–10(–20) mm, ± pilose, bracts 1–5, linear-lanceolate, pilose, grading into phyllaries.
ascending, 0.2–6 cm, glabrate, densely bracteate, bracts linear-subulate, scabrous- or ciliate-margined, often revolute, grading with phyllaries.
campanulate, 3–5.5 mm.
campanulate to cylindro-campanulate, 4.5–8 mm.
(10–)15–26;
corollas usually white, rarely pinkish or light purple to blue, laminae 3.5–5.5(–8) × 0.5–1.5 mm.
(10–)13–20(–25);
corollas usually pale to azure blue to violet-purple, (rarely rosy, white or bluish white), laminae (5–)8–12(–14) × 1.4–1.7 mm.
12–25;
corollas cream or light yellow turning magenta or purple (ampliate), 2.5–4(–4.5) mm, tubes shorter than funnelform throats, lobes slightly spreading to reflexed, lanceolate, 0.7–1.1 mm.
(15–)20–25(–30);
corollas light yellow turning deep purple, 4–5 mm, tubes much shorter than narrowly funnelform throats, lobes triangular to lanceolate, 0.4–0.7 mm (lobes sparsely hairy).
in (3–)4–6 series, unequal, appressed or ± spreading, linear-obovate (outer) to oblong-lanceolate to linear (inner), bases indurate 1/3–3/4, margins narrowly scarious to apices, erose, hyaline, ciliate, green zones lanceolate, apices acute to acuminate, mucronulate, faces (outer) sparsely pilose or glabrous (var. glabratum), (inner) glabrous.
in (3–)4–6 series, appressed or outer slightly spreading, lanceolate to oblong-lanceolate, strongly unequal, bases indurate 1/2–3/4, margins scarious, erose, hyaline, ciliolate, apical green zones diamond-shaped, apices acute to acuminate or caudate (then tips often involute), mucronulate to apiculate, faces glabrous.
in ample, open, paniculiform arrays, branches ± ascending or divaricate to long-arching, ± secund.
in open, paniculiform arrays, branches ascending, stiff, sometimes long-arching and peduncles secund, ± ridged, densely leafy with small, ± appressed branch leaves, ± strigose.
gray or tan, oblong-obovoid, sometimes ± compressed, 1.2–1.8(–2) mm, 3–5-nerved, faces strigillose;
pappi whitish to white, 3–3.5 mm.
dull purple or stamineous with purple streaks, oblong-obovoid, ± compressed, 1.8–2 mm, 4–5-nerved, faces glabrate to sparsely strigose;
pappi cream or slightly rose-tinged, 3–4 mm.
= 32.
Symphyotrichum ontarionis
Symphyotrichum oolentangiense
Varieties 2 (2 in the flora).
Symphyotrichum ontarionis is often confused with S. lateriflorum, from which it can be distinguished by its shorter disc corolla lobes and abaxial leaf faces either moderately to densely hairy or glabrous to glabrate (var. glabratum), and without hairs along midveins (as is typical of S. lateriflorum).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
A. G. Jones (1989) suggested that Symphyotrichum oolentangiense hybridizes with S. drummondii and S. laeve. Two color morphs, Aster azureus Lindley forma incarnatus Farwell and “forma albidus (the latter not validly published and incorrectly attributed to Steyermark by M. L. Fernald 1950), have been described but are not recognized here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Abaxial leaf faces moderately to densely hairy | var. ontarionis |
1. Abaxial leaf faces glabrous or glabrate | var. glabratum |
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