Symphyotrichum falcatum var. commutatum

(Torrey & A. Gray) G. L. Nesom

Phytologia 77: 281. 1995.

Basionym: Aster multiflorus var. commutatus Torrey & A. Gray Fl. N. Amer. 2: 125. 1841
Synonyms: Aster commutatus (Torrey & A. Gray) A. Gray Aster commutatus var. crassulus (Rydberg) S. F. Blake Aster commutatus var. polycephalus (Rydberg) S. F. Blake Aster cordineri Linnaeus Aster crassulus Lindley Aster ericoides var. commutatus (Torrey & A. Gray) B. Boivin Aster ericoides var. polycephalus (Rydberg) F. C. Gates Aster falcatus subsp. commutatus (Torrey & A. Gray) A. G. Jones Aster falcatus var. commutatus (Torrey & A. Gray) A. G. Jones Aster falcatus var. crassulus (Rydberg) Cronquist Aster incanopilosus Aster multiflorus var. incanopilosus (Lindley) Rydberg Symphyotrichum falcatum subsp. commutatum (Torrey & A. Gray) Semple Symphyotrichum falcatum var. commutatum (Torrey & A. Gray) G. L. Nesom Symphyotrichum falcatum var. crassulum (Torrey & A. Gray) G. L. Nesom Virgulus falcatus subsp. commutatus (Torrey & A. Gray) Schaak
Treatment appears in FNA Volume 20. Treatment on page 497.

Plants colonial, sometimes ± cespitose, usually densely hairy; long-rhizomatous (stems single) or short-rhizomatous with rhizomes branched and entangled (stems clumped), new shoots developing at ends of elongate rhizomes. Stems usually 1, sometimes 1–5+. Peduncles stout, bracts 2–10+. Phyllaries ± unequal, apices strongly squarrose. 2n = 30.


Phenology: Flowering Aug–Oct(–Nov, south).
Habitat: Dry soils, plains, hills, prairies, roadsides, along railroad rights-of-way, stream banks
Elevation: 200–2500+ m

Distribution

V20-1115-distribution-map.gif

Alta., Man., Ont., Sask., Ariz., Colo., Ill., Iowa, Kans., Minn., Mo., Mont., Nebr., N.Mex., N.Dak., Okla., S.Dak., Tex., Utah, Wis., Wyo., Mexico (Chihuahua), Mexico (Coahuila), Mexico (Durango), Mexico (Jalisco), Mexico (Nuevo León), Mexico (Sonora)

Discussion

Variety commutatum is introduced in Ontario, Illinois, Missouri, and Wisconsin, and possibly other eastern states. A. G. Jones (1978) treated it as a subspecies with two varieties on the basis of habit and head traits. Variety commutatum in the sense of Jones has decumbent or ascending stems usually branched proximally, heads in racemiform or diffuse paniculiform arrays, rarely secund, usually with 40–50(–60) florets. Variety crassulum in the sense of Jones has erect stems branched near the middle, with spreading branches, heads in paniculiform arrays, often somewhat secund, and with 35–40(–45) florets. Intermediates occur; Jones’s varieties are not recognized here.

The name Aster ramulosus Lindley var. incanopilosus Lindley (in W. J. Hooker 1834) has priority at the varietal level; the combination in Symphyotrichum has yet to be made.

Selected References

None.

Lower Taxa

None.
not tailed +, rounded +  and obtuse +
serrate +, entire +  and spine-tipped +
distinct +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
hispid-strigose +, glabrate +  and moderately strigose +
subequal +
scarious +
3mm +  and 10mm +
usually triangular +  and linear +
usually deltate +  and lanceolate +
racemiform +  and diffuse-paniculiform +
indeterminate +  and determinate +
Luc Brouillet +, John C. Semple +, Geraldine A. Allen +, Kenton L. Chambers +  and Scott D. Sundberg† +
(Torrey & A. Gray) G. L. Nesom +
serrate +  and entire +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
glabrate +  and moderately strigose +
cuneate +, acute +  and obtuse rounded +
indurate +
3mm;10mm +
Aster multiflorus var. commutatus +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
glabrate +  and moderately strigose +
linear-oblong;linear-lanceolate +
reduced +
2mm;3mm +
rugulose +  and muricate +
linear +  and lanceolate +
barbellulate +  and barbellate +
branched +  and cormoid +
not 2-lipped +  and actinomorphic +
yellow becoming brown +, pink +, blue +  and white +
at maturity , more or less ampliate , tubes usually shorter +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
not compressed +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
Alta. +, Man. +, Ont. +, Sask. +, Ariz. +, Colo. +, Ill. +, Iowa +, Kans. +, Minn. +, Mo. +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, Okla. +, S.Dak. +, Tex. +, Utah +, Wis. +, Wyo. +, Mexico (Chihuahua) +, Mexico (Coahuila) +, Mexico (Durango) +, Mexico (Jalisco) +, Mexico (Nuevo León) +  and Mexico (Sonora) +
200–2500+ m +
serrate +  and entire +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
strigose +, hispid-strigose +, hispido-strigose +, glabrate +  and moderately strigose +
acute;obtuse rounded +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Dry soils, plains, hills, prairies, roadsides, along railroad rights-of-way, stream banks +
disciform +  and radiate +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
linear-lanceolate +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
18mm;30mm +
1.1mm;1.4mm +
sessile +  and petiolate +
cauline +  and basal +
decurrent +
triangular +
entire +  and serrate +
10mm;40mm +
glabrate +  and moderately strigose +
acute +  and obtuse rounded +
3mm +  and 10mm +
2-carpellate +
persistent +
25 +  and 40 +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (4 cm40 mm <br />0.04 m <br />) +
Flowering Aug–Oct(–Nov, south). +
oblanceolate or spatulate +  and linear +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
exalbuminous +
branched +  and simple +
ascending +  and erect +
1 +  and 5 +
appendaged +  and truncate +
papillate +  and smooth +
Aster commutatus +, Aster commutatus var. crassulus +, Aster commutatus var. polycephalus +, Aster cordineri +, Aster crassulus +, Aster ericoides var. commutatus +, Aster ericoides var. polycephalus +, Aster falcatus subsp. commutatus +, Aster falcatus var. commutatus +, Aster falcatus var. crassulus +, Aster incanopilosus +, Aster multiflorus var. incanopilosus +, Symphyotrichum falcatum subsp. commutatum +, Symphyotrichum falcatum var. commutatum +, Symphyotrichum falcatum var. crassulum +  and Virgulus falcatus subsp. commutatus +
Symphyotrichum falcatum var. commutatum +
Symphyotrichum falcatum +
variety +
at maturity , more or less ampliate , tubes usually shorter +
ampliate +
cespitose +  and colonial +
stipitate-glandular +
10 cm100 mm <br />0.1 m <br /> (80 cm800 mm <br />0.8 m <br />) +
short-rhizomatous +  and long-rhizomatous +
plant +, cespitose +  and colonial +
clear +  and green +
acuminate +  and attenuate +