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southern swamp aster

slender aster

Habit Plants 20–80 cm; in clumps and clones, eglandular; rhizomes creeping, herbaceous and thin, becoming thick and woody, scaly. Plants 15–50(–70) cm, in clumps, eglandular; caudices thickened, woody, ovoid to spheric.
Stems

1–10+, erect, often reddish, simple, straight (brittle), proximally glabrous, glabrescent, or sparsely strigillose, distally strigillose or ± villoso-hirsute (at least in arrays).

1–8+, erect, simple, strict, glabrescent, usually ± densely villous distally.

Leaves

basal and cauline, firm, only midnerves evident, margins indurate, entire or sometimes remotely spinulose-serrate, scabrous, spines indurate, ± pronounced, apices mucronate or indurate, abaxial faces glabrous or scabrous, adaxial sparsely hirtellous, distal often more hairy;

basal and proximalmost cauline withering by flowering, petioles (often marcescent, to 20 mm), bases sheathing, blades elliptic to lanceolate (basal) or linear-lanceolate, ± arcuate (proximal), 15–103 × 5–9 mm, bases cuneate, apices obtuse (basal) to acute;

cauline progressively sessile (petioles more winged) and reduced, blades lanceolate or linear-lanceolate to linear, ± arcuate, 18–132+ × 2–6 mm, margins sometimes revolute, apices acute.

basal and cauline, thick, firm (only midnerves conspicuous), margins entire or nearly so, indurate, scabrous, apices indurate, mucronate, faces scabrous (especially distal) to sometimes glabrous, adaxial sometimes villous (especially proximal) at least along midnerves;

basal often withering by flowering (bases sometimes marcescent), petioles erect, longer than blades, bases sheathing, winged, ciliate, blades narrowly elliptic to ovate or obovate, 20–70 × 8–20 mm, bases cuneate, margins sometimes crenulate-serrulate, teeth mucronate, apices obtuse to rounded;

cauline usually sessile, sometimes subsessile (ascending), lanceolate to oblanceolate, 15–80(–90) × 2.5–12 mm, bases sheathing to auriculate-clasping (distal), apices acute.

Peduncles

ascending, usually mostly 1–10+ cm (seldom not elongating, sometimes those of young heads appearing short or absent), thin, hirtello-puberulent to villoso-hirsute;

bracts 2–5, often 1–2 subtending heads, sometimes phyllary-like (bases pale, indurate).

slender, villous;

bracts 1–2, often 1 near heads, leaflike (bases sometimes indurate and white as in phyllaries).

Involucres

campanulate, 9–11 mm, much shorter than pappi.

cylindro-campanulate, 6.5–9 mm, slightly shorter than pappi.

Ray florets

15–35;

corollas deep lavender to purple, (10–)15–20 × 1–2.3 mm.

(5–)8–14;

corollas blue-violet to rose-purple or bluish, often pale, 5–8(–10) × 1–1.8 mm.

Disc florets

25–60;

corollas yellow, 5.5–7 mm, slightly ampliate, tubes much shorter than cylindro-funnelform throats, lobes spreading, lanceolate-acuminate, 0.75–1.1 mm.

10–20;

corollas pale yellow, 5.5–6.2 mm, not ampliate, tubes longer than narrowly funnelform throats, lobes triangular, 0.65–0.9 mm.

Phyllaries

40–65+ in 4–5 series, lanceolate or oblong (outer) to linear-oblanceolate or linear (inner), unequal, membranous, bases indurate, rounded (particularly outer), green zones well defined, slightly expanded in distal 1/3–2/3 (foliaceous), reaching margins (outer wholly foliaceous, outermost are bracts subtending heads) to 1/6 or less and not reaching margins or none (inner), margins sometimes distally purplish (particularly inner), indurate, narrowly scarious, erose proximally to nearly completely so (inner), densely ciliate proximally (scarious part) to distally scabrous (foliaceous part), apices loose and often spreading, sometimes squarrose, obtuse to sometimes acute, mucronate, faces sparsely to densely strigillose.

24–35 in 4–5 series, oblong (outer) to lanceolate (inner), unequal, coriaceous (outer) to membranous (inner), bases indurate, rounded (outer), margins hyaline, narrowly scarious, ± erose, ciliate (outer), apices reflexed, green (except innermost), purple-margined, less scarious, rounded or obtuse (outer) to acuminate (inner), mucronate, abaxial faces glabrous or obscurely puberulent, eglandular.

Heads

(1–)4–10+ in open, corymbiform arrays, seldom borne singly, with ascending branches.

3–55+ in flat-topped, corymbiform arrays, branches ascending, slender.

Cypselae

stramineous to tawny, cylindric to narrowly obovoid, slightly compressed, 2.3–3.6 mm, ribs 10–16, sparsely strigillose;

pappi of stramineous (firm, sometimes apically clavellate) bristles 5–6.7 mm, ± equaling disc corollas.

stramineous, cylindro-obconic, 1.75–2.6 mm, ribs 9–12 (crowded), faces glabrate to strigillose;

pappi of tawny to cinnamon bristles 5.9–6.2 mm, equaling disc corollas.

2n

= 36.

= 18.

Eurybia paludosa

Eurybia compacta

Phenology Flowering late summer–fall. Flowering midsummer–early fall.
Habitat Moist savannas, margins of pools and swamps, low pinelands, seldom on sand hills of coastal plains, open hammocks Dry, sandy places, dry to moist pinelands, oak-thickets, bogs, barrens
Elevation 0–100 m (0–300 ft) 0–200 m (0–700 ft)
Distribution
from FNA
FL; GA; NC; SC
[WildflowerSearch map]
[BONAP county map]
from FNA
DE; GA; MD; NC; NJ; SC; VA
[WildflowerSearch map]
[BONAP county map]
Discussion

Eurybia paludosa is often confused with E. hemispherica, with which it is closely related. It is present on the Atlantic coastal plain from North Carolina to northeastern Florida. The two species are disjunct geographically and ecologically, even when they occur in the same states. In North Carolina, for instance, E. paludosa is coastal while E. hemispherica is found in the mountains. In northern Florida, the former is found only in Nassau County, while the latter is present only in the western panhandle. Their ranges do not overlap.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Eurybia compacta may be extirpated from much of its original range (Georgia, Maryland, South Carolina, Virginia) and may now be of conservation concern. It is present on the Atlantic coastal plains and outer Piedmont. A. Cronquist (1980) stated that it approaches E. surculosa on one hand, and E. avita and E. paludosa on the other. This reflects the close affinity between sections Calliastrum and Heleastrum (see above). I have seen no voucher for the Alabama report.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 20, p. 380. FNA vol. 20, p. 377.
Parent taxa Asteraceae > tribe Astereae > Eurybia Asteraceae > tribe Astereae > Eurybia
Sibling taxa
E. avita, E. chlorolepis, E. compacta, E. conspicua, E. divaricata, E. eryngiifolia, E. furcata, E. hemispherica, E. integrifolia, E. jonesiae, E. macrophylla, E. merita, E. mirabilis, E. radula, E. radulina, E. saxicastelli, E. schreberi, E. sibirica, E. spectabilis, E. spinulosa, E. surculosa, E. ×herveyi
E. avita, E. chlorolepis, E. conspicua, E. divaricata, E. eryngiifolia, E. furcata, E. hemispherica, E. integrifolia, E. jonesiae, E. macrophylla, E. merita, E. mirabilis, E. paludosa, E. radula, E. radulina, E. saxicastelli, E. schreberi, E. sibirica, E. spectabilis, E. spinulosa, E. surculosa, E. ×herveyi
Synonyms Aster paludosus, Heleastrum paludosum Aster gracilis, Aster surculosus var. gracilis
Name authority (Aiton) G. L. Nesom: Phytologia 77: 261. (1995) G. L. Nesom: Phytologia 77: 259. (1995)
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