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southern swamp aster

aster rude, low rough aster, rough wood-aster

Habit Plants 20–80 cm; in clumps and clones, eglandular; rhizomes creeping, herbaceous and thin, becoming thick and woody, scaly. Plants 10–100 cm; in lax clones, eglandular; rhizomes elongate or short, filiform or cordlike, herbaceous, remotely scaly.
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, erect, straight, often reddish, simple, glabrous or glabrescent to sparsely villous proximally, 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.

cauline, rugose-veined, margins ± revolute, ± remotely, ± deeply serrate, scabrous, teeth ± indurate (mucronate), apices mucronulate, abaxial faces scabrous, adaxial ± villous, particularly on veins (increasingly so distally);

proximalmost withering by flowering, winged-petiolate, petioles equaling or longer than blades, bases ± sheathing, sometimes marcescent, blades spatulate to oblanceolate, 10–42 × 3–8 mm, sometimes reduced, smaller than mid, bases attenuate to cuneate, apices obtuse to acute;

mid sessile, lanceolate, oblanceolate, or narrowly obovate to narrowly elliptic or elliptic, (23–)30–115 × 5–36 mm, gradually reduced distally, bases tapering or rounded to ± auriculate-clasping (often narrowed above base), apices acute to acuminate;

distal (arrays) sessile, (6–)10–40 × 2–7 mm.

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).

± densely villous;

bracts 0–2, sometimes subtending heads.

Involucres

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

campanulate, 5.5–9 mm, shorter than pappi.

Ray florets

15–35;

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

13–30;

corollas pale blue-violet, 10.5–15 × 1.4–2 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.

37–72;

corollas yellow, 4.5–6 mm, slightly ampliate, 4.8–5.8 mm, tube lengths about twice funnelform throats (2.7–3.4 mm), lobes erect, lanceolate, 0.6–1 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.

30–50 in 4–5 series, oblong or oblong-lanceolate, seldom ovate (outer), lanceolate to linear-lanceolate (inner), strongly unequal, membranous, bases indurate, rounded (outer), green zones full-width, occasionally purplish (inner), in distal 1/2 (outer; rarely 2/3 and foliaceous) to less than 1/6 and paler or none (inner), margins hyaline (seldom purplish), narrowly scarious, ± erose, densely ciliate, apices usually appressed, often squarrose, usually acute, sometimes obtuse, mucronulate, faces glabrous or sparsely strigillose.

Heads

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

1–25+ in open corymbiform arrays or borne singly.

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.

tawny to stramineous, fusiform to cylindro-obconic, slightly compressed, 2.7–3.5 mm, ribs 8–18 (stramineous or reddish brown), ± crowded, faces glabrous;

pappi of pale cinnamon bristles 4.5–5.2 mm, shorter than disc corollas.

2n

= 36.

= 18.

Eurybia paludosa

Eurybia radula

Phenology Flowering late summer–fall. Flowering late summer–early fall.
Habitat Moist savannas, margins of pools and swamps, low pinelands, seldom on sand hills of coastal plains, open hammocks Fens, sphagnum bogs, lake and creek shores, edges of or openings in wet spruce or tamarack forests, open boggy woods, ± wet meadows, ditches
Elevation 0–100 m (0–300 ft) 0–600+ m (0–2000+ ft)
Distribution
from FNA
FL; GA; NC; SC
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; DC; DE; KY; MA; MD; ME; NH; NJ; NY; PA; RI; VA; VT; WV; NB; NL; NS; ON; PE; QC; SPM
[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 radula reaches its northwestern limit south of James Bay in northeastern Ontario, where it is rare (J. C. Semple et al. 2002). It is vulnerable in most of its United States range. Aster radula var. strictus (Pursh) A. Gray (for which no combination exists in Eurybia) appears to be a reduced, more slender plant with 1–8 heads (M. L. Fernald 1950) from more northern parts of the range (Newfoundland and Labrador, northern Quebec, northern Nova Scotia), presumably due to harsher conditions; an entire spectrum of intermediates appears to exist with the typical variety to the south, however, and it is unclear whether the variety should be recognized. It seems that the common name, rough aster, stems from a misinterpretation of the Latin epithet radula, which means scraper (rough would be radulans).

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

Source FNA vol. 20, p. 380. FNA vol. 20, p. 371.
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. compacta, E. conspicua, E. divaricata, E. eryngiifolia, E. furcata, E. hemispherica, E. integrifolia, E. jonesiae, E. macrophylla, E. merita, E. mirabilis, E. paludosa, E. radulina, E. saxicastelli, E. schreberi, E. sibirica, E. spectabilis, E. spinulosa, E. surculosa, E. ×herveyi
Synonyms Aster paludosus, Heleastrum paludosum Aster radula, Aster radula var. strictus
Name authority (Aiton) G. L. Nesom: Phytologia 77: 261. (1995) (Aiton) G. L. Nesom: Phytologia 77: 261. (1995)
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