Symphyotrichum oolentangiense

(Riddell) G. L. Nesom

Phytologia 77: 288. 1995.

Common names: Azure or skyblue aster
Basionym: Aster oolentangiensis Riddell W. J. Med. Phys. Sci. 8: 495. 1835
Synonyms: Aster azureus Lindley Aster azureus var. poaceus (E. S. Burgess) Fernald Aster azureus var. scabrior Engelmann ex E. S. Burgess Aster capillaceus Engelmann ex E. S. Burgess Aster poaceus Aster vernalis
Treatment appears in FNA Volume 20. Treatment on page 507. Mentioned on page 471, 473, 475, 500, 505, 506, 508, 509.

Perennials 20–150 cm, cespitose; short-rhizomatous or with branched, woody caudices. Stems 1–5+, erect (straight), glabrate to hispidulous, distally pilosulous to strigillose in arrays. Leaves 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 lanceovate, 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 ovatelanceolate 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. Heads in open, paniculiform arrays, branches ascending, stiff, sometimes long-arching and peduncles secund, ± ridged, densely leafy with small, ± appressed branch leaves, ± strigose. Peduncles ascending, 0.2–6 cm, glabrate, densely bracteate, bracts linear-subulate, scabrous or ciliate-margined, often revolute, grading with phyllaries. Involucres campanulate to cylindro-campanulate, 4.5–8 mm. Phyllaries 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. Ray-florets (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. Disc-florets (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). Cypselae 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. 2n = 32.


Phenology: Flowering Aug–Oct.
Habitat: Open, dry, sandy, loamy, or rocky soils, dry to wet (seasonally drying) prairies, alvars, glades, bluffs, dunes, barrens, open deciduous woods, oak and/or pine savannas
Elevation: 50–500 m

Distribution

V20-1132-distribution-map.gif

Ont., Ala., Ark., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Mich., Minn., Miss., Mo., Nebr., N.Y., Ohio, Okla., Pa., S.Dak., Tenn., Tex., Wis., Mexico (Coahuila)

Discussion

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.

Selected References

None.

Lower Taxa

None.

"thick" is not a number.

strigose +  and piloso-strigose or hirsute +
not tailed +, rounded +  and obtuse +
long-petiolate +
15 cm150 mm <br />0.15 m <br /> (18 cm180 mm <br />0.18 m <br />) +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
distinct +
4 cm40 mm <br />0.04 m <br /> (15 cm150 mm <br />0.15 m <br />) +
subequal +
scarious +
10mm +  and 40mm +
usually triangular +  and linear +
usually deltate +  and lanceolate +
paniculiform +  and open +
indeterminate +  and determinate +
Luc Brouillet +, John C. Semple +, Geraldine A. Allen +, Kenton L. Chambers +  and Scott D. Sundberg† +
(Riddell) G. L. Nesom +
long-petiolate +
15 cm150 mm <br />0.15 m <br /> (18 cm180 mm <br />0.18 m <br />) +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
4 cm40 mm <br />0.04 m <br /> (15 cm150 mm <br />0.15 m <br />) +
attenuate +  and cuneate or more or less rounded +
indurate +
10mm;40mm +
Aster oolentangiensis +
long-petiolate +
15 cm150 mm <br />0.15 m <br /> (18 cm180 mm <br />0.18 m <br />) +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (8 cm80 mm <br />0.08 m <br />) +
linear-lanceolate;subulate +
reduced +
1mm;10mm +
rugulose +  and muricate +
ciliate-margined +
linear-subulate +
long-arching;ascending +
barbellulate +  and barbellate +
sessile +  and petiolate +
Azure or skyblue aster +
not 2-lipped +  and actinomorphic +
light yellow +, usually pale +  and azure blue +
beaked +, 2-ribbed +  and 5-ribbed +
stamineous +  and purple +
strigillose +  and glabrous +
compressed +  and oblong-obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
winged +, short-petiolate +  and sessile +
Ont. +, Ala. +, Ark. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, N.Y. +, Ohio +, Okla. +, Pa. +, S.Dak. +, Tenn. +, Tex. +, Wis. +  and Mexico (Coahuila) +
50–500 m +
glabrate +  and sparsely strigose +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Open, dry, sandy, loamy, or rocky soils, dry to wet (seasonally drying) prairies, alvars, glades, bluffs, dunes, barrens, open deciduous woods, oak and/or pine savannas +
disciform +  and radiate +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
campanulate;cylindro-campanulate +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
2 (?) +  and 5 (?) +
1.4mm;1.7mm +
sessile +  and petiolate +
cauline +  and basal +
decurrent +
reflexed;spreading;erect +
triangular +  and lanceolate +
long-petiolate +
entire +  and crenate-serrate +
15 cm150 mm <br />0.15 m <br /> (18 cm180 mm <br />0.18 m <br />) +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
40mm;150mm +
obtuse +  and acute +
10mm +  and 40mm +
2-carpellate +
rose-tinged +  and cream +
persistent +
25 +  and 40 +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
bracteate +, leafy +  and secund +
glabrate +  and strigose +
0.2 cm2 mm <br />0.002 m <br /> (6 cm60 mm <br />0.06 m <br />) +
Flowering Aug–Oct. +
oblanceolate or spatulate +  and linear +
strongly unequal +  and subequal +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
exalbuminous +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.1mm;0.2mm +
branched +  and simple +
1 +  and 5 +
appendaged +  and truncate +
papillate +  and smooth +
Aster azureus +, Aster azureus var. poaceus +, Aster azureus var. scabrior +, Aster capillaceus +, Aster poaceus +  and Aster vernalis +
Symphyotrichum oolentangiense +
Symphyotrichum sect. Symphyotrichum +
species +
funnelform-campanulate +  and cylindric +
at maturity , more or less ampliate , tubes usually shorter +
ampliate +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
with branched , woody caudices +  and short-rhizomatous +
20 cm200 mm <br />0.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
tree +, shrub +  and subshrub +
diamond--shaped +