Symphyotrichum tradescantii

(Linnaeus) G. L. Nesom

Phytologia 77: 293. 1995.

Common names: Tradescant’s or shore aster aster de Tradescant
Endemic
Basionym: Aster tradescantii Linnaeus Sp. Pl. 2: 876. 1753 (as tradescanti)
Treatment appears in FNA Volume 20. Treatment on page 516. Mentioned on page 469, 501, 519.

Perennials, 5–70 cm, cespitose; short-rhizomatous. Stems 1–5+, ascending to erect (straight, slender, 1–2.5 (–3) mm diam.), glabrous. Leaves thin, margins scabrous to scabrellous or eciliate, apices mucronulate, faces glabrous; basal persistent or withering by flowering, petiolate (petioles slightly winged, sheathing), blades spatulate to elliptic or oblanceolate, 10–40 × 5–11 mm, bases cuneate to attenuate, margins crenate-serrate, apices obtuse to acute; proximal cauline persistent or withering by flowering, ± broadly winged-petiolate or sessile, blades oblong, lanceolate or elliptic-lanceolate to oblanceolate, or linear-lanceolate, 20–100 × 3–9 mm, bases attenuate to cuneate, slightly clasping, margins serrulate or entire; distal sessile, blades oblanceolate to linear-lanceolate or linear, 10–60 × 1–7 mm, gradually reduced distally, bases cuneate to tapering, margins serrulate or entire, apices acute to acuminate. Heads {(10–) 25–100} in paniculiform arrays, branches ascending (1–10 heads per branch). Peduncles ascending, 0.2–2.5+ cm, glabrous, bracts 1–4, subulate to linear. Involucres cylindro-campanulate, 3.3–4.5 (–5) mm. Phyllaries in 4–5 series oblong-lancoelate (outer) to linear-lanceolate (inner) or linear (innermost), unequal, bases indurate 1/2+, margins scarious, erose, hyaline, ciliolate, green zones lanceolate, apices acute to acuminate or caudate, mucronulate or apiculate, sometimes purplish, faces glabous. Ray-florets 14–27; corollas white, laminae 4.3–8.2 × 0.7–0.8 mm. Disc-florets 20–30; corollas pale-yellow becoming purplish, 3–4.1 mm, tubes shorter to nearly equaling funnelform throats, lobes lanceolate, 0.5–1 mm. Cypselae tan (nerves stramineous), obovoid, ± compressed, 3.5–4 mm, 4–5-nerved, faces strigillose; pappi white, 3–3.6 mm. 2n = 16, 32.


Phenology: Flowering Jul–Aug(–Sept).
Habitat: Damp, rocky and gravelly shores, silt- or loam-filled cracks in rocky rapids of streams or along freshwater estuaries
Elevation: 0–200+ m

Distribution

V20-1150-distribution-map.gif

N.B., Nfld. and Labr. (Nfld.), N.S., Que., Maine, Mass., N.H., N.J., N.Y., R.I., Vt.

Discussion

Selected References

None.

Lower Taxa

None.

"thin" is not a number.

not tailed +, rounded +  and obtuse +
distinct +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
subequal +
scarious +
5mm +  and 11mm +
usually triangular +  and linear +
usually deltate +  and lanceolate +
paniculiform +
indeterminate +  and determinate +
Luc Brouillet +, John C. Semple +, Geraldine A. Allen +, Kenton L. Chambers +  and Scott D. Sundberg† +
(Linnaeus) G. L. Nesom +
sessile +, winged-petiolate +  and petiolate +
entire +, serrulate +  and crenate-serrate +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
cuneate +  and tapering +
indurate +
3mm;9mm +
Aster tradescantii +
sessile +, winged-petiolate +  and petiolate +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
oblanceolate;linear-lanceolate or linear +
reduced +
1mm;7mm +
rugulose +  and muricate +
subulate +  and linear +
barbellulate +  and barbellate +
sessile +  and petiolate +
Tradescant’s or shore aster +  and aster de Tradescant +
not 2-lipped +  and actinomorphic +
pale-yellow becoming purplish +  and white +
at maturity , more or less ampliate , tubes usually shorter +
0.3 cm3 mm <br />0.003 m <br /> (0.41 cm4.1 mm <br />0.0041 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
strigillose +  and glabrous +
compressed +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
N.B. +, Nfld. and Labr. (Nfld.) +, N.S. +, Que. +, Maine +, Mass. +, N.H. +, N.J. +, N.Y. +, R.I. +  and Vt. +
0–200+ m +
strigillose +, glabous +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Damp, rocky and gravelly shores, silt- or loam-filled cracks in rocky rapids of streams or along freshwater estuaries +
disciform +  and radiate +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
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 />) +
cylindro-campanulate +
0.33 cm3.3 mm <br />0.0033 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
1.8 cm18 mm <br />0.018 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
4.3mm;8.2mm +
2 (?) +  and 5 (?) +
0.7mm;0.8mm +
sessile +  and petiolate +
cauline +  and basal +
decurrent +
reflexed;spreading;erect +
lanceolate +
sessile +, winged-petiolate +  and petiolate +
entire +, serrulate +  and crenate-serrate +
20mm;100mm +
ciliolate +  and eciliate +
scabrous +  and scabrellous +
attenuate +  and cuneate +
3mm +  and 9mm +
2-carpellate +
persistent +
25 +  and 40 +
0.3 cm3 mm <br />0.003 m <br /> (0.36 cm3.6 mm <br />0.0036 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Flowering Jul–Aug(–Sept). +
oblanceolate or spatulate +  and linear +
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 />) +
linear +  and linear-lanceolate +
0.1mm;0.2mm +
branched +  and simple +
straight +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
ascending +  and erect +
1 +  and 5 +
slender +
appendaged +  and truncate +
papillate +  and smooth +
Aster sect. Heterastrum +  and Aster subg. Symphyotrichum +
Symphyotrichum tradescantii +
Symphyotrichum sect. Symphyotrichum +
species +
funnelform-campanulate +  and cylindric +
ampliate +
5 cm50 mm <br />0.05 m <br /> (70 cm700 mm <br />0.7 m <br />) +
tree +, shrub +  and subshrub +
lanceolate +