48.
Symphyotrichum lateriflorum
(Linnaeus) Á. Löve & D. Löve, Taxon. 31: 359. 1982.
Calico or one-sided or white woodland or starved aster, aster latériflore
Solidago lateriflora
Linnaeus, Sp. Pl. 2: 879. 1753;
Aster lateriflorus
(Linnaeus) Britton
Perennials,
20—120(—150) cm, cespitose; with short, woody, branched caudices, or short-rhizomatous.
Stems
1—5+, ascending to erect (± arching, slender, brittle), ± densely pilose or villous to glabrate or glabrous (particularly proximally).
Leaves
thin, membranous, margins serrate to serrulate, scabridulous, apices acute to acuminate, sometimes caudate, mucronulate, abaxial faces glabrous, midveins usually ± densely pilose to glabrate, rarely glabrous, adaxial scabrous (short-strigose) to glabrate; basal usually withering by flowering, sometimes persisting (new vernal rosettes often developing at flowering), petiolate to subpetiolate (petioles narrowly to ± broadly winged, ciliate, bases ± sheathing), blades oblanceolate, lance-ovate or ovate to spatulate or suborbiculate, 5—35 × 7—25 mm, abruptly attenuate, margins crenate-serrate, apices obtuse to rounded or acute; proximal cauline mostly withering by flowering, sessile or subpetiolate (petioles broadly winged), blades usually ovate or elliptic to elliptic-oblanceolate or lanceolate, rarely linear-lanceolate, (30—)50—100(—150) × (2—)10—20(—35) mm, greatly reduced distally, bases attenuate to cuneate; distal sessile, blades ovate, lance-ovate, lance-elliptic, or oblanceolate to lance-linear or linear, 10—150 × 1—30 mm, progressively reduced distally, branch leaves abruptly smaller, bases cuneate, margins sometimes entire.
Heads
in ample, open, diffuse, ± pyramidal, paniculiform arrays, branches divaricate to long-arching or ± ascending, slender, wiry, secund; usually sessile, sometimes peduncles 0.1—1 cm+, ± pilose, bracts 1—7, linear or subulate to oblong-lanceolate, foliaceous, grading into phyllaries.
Involucres
cylindro-campanulate, (3.5—)4—6(—7) mm.
Phyllaries
in 3—4(—6) series, appressed or slightly spreading, oblong-lanceolate or -oblanceoalte (outer) to linear (inner), unequal, bases indurate
1
/ 3 —
2
/ 3 , margins scarious, erose, hyaline or sometimes reddish, ± ciliolate, green zones lanceolate to ± diamond-shaped, apices (outer) acute, callus-pointed, (mid) acute to acuminate, or obtuse, sometimes purplish, abaxial faces glabrous (outer), mid sparsely puberulent.
Ray florets
8—15(—23); corollas white, rarely pinkish or purplish, laminae (3—)4—5(—8) × 0.9—1.2 mm.
Disc florets
8—16(—20); corollas cream to light yellow turning pink or reddish purple, (2.5—)3—5 mm, tubes shorter than funnelform-campanulate throats, lobes strongly reflexed, lanceolate, 0.9—1.7 mm.
Cypselae
gray or tan, oblong-obovoid, sometimes ± compressed, (1.3—)1.8—2.2 mm, 3—5-nerved, faces sparsely strigillose;
pappi
white to pinkish, 3—4 mm.
2
n
= 16, 32, 48.
Flowering Aug—Oct. Relatively shaded habitats, dry to humid soils, usually deciduous woodlands (beech—maple, oak—hickory, mixed hardwoods), sometimes conifer woods, sometimes swamp forests (conifer or dediduous), edges of woods, meadows, usually rocky or sandy stream and pond shores, roadsides; 0—400 m; Man., N.B., N.S., Ont., P.E.I., Que.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis.
Symphyotrichum lateriflorum
has been reported in British Columbia as an ephemeral that did not persist. G. L. Nesom (1994b) and J. C. Semple et al. (2002) recognized several varieties within the complex: var.
lateriflorum
(syn.
Aster vimineus
Lamarck); var.
angustifolium
(Wiegand) G. L. Nesom (syn.
A. lateriflorus
var.
angustifolius
Wiegand); var.
flagellare
(Shinners) G. L. Nesom (syn.
A. lateriflorus
var.
flagellaris
Shinners,
A. lateriflorus
var.
indutus
Shinners); var.
hirsuticaule
(Lindley ex de Candolle) G. L. Nesom [syn.
A. hirsuticaulis
Lindley ex de Candolle,
A. lateriflorus
var.
hirsuticaulis
(Lindley ex de Candolle) Porter]; var.
horizontale
(Desfontaines) G. L. Nesom [syn.
A. horizontalis
Desfontaines,
A. lateriflorus
var.
horizontalis
(Desfontaines) Farwell]; var.
spatelliforme
(E. S. Burgess) G. L. Nesom [syn.
A. spatelliformis
E. S. Burgess,
A. lateriflorus
var.
spatelliformis
(E. S. Burgess) A. G. Jones]; and var.
tenuipes
(Wiegand) G. L. Nesom (syn.
A. lateriflorus
var.
tenuipes
Wiegand,
A. acadiensis
Shinners). Much genetic and phenotypic variation is encountered within the complex; a thorough study is needed before a coherent taxonomy can be achieved.
