The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

aster rude, low rough aster, rough wood-aster

slender aster

Habit Plants 10–100 cm; in lax clones, eglandular; rhizomes elongate or short, filiform or cordlike, herbaceous, remotely scaly. Plants 15–50(–70) cm, in clumps, eglandular; caudices thickened, woody, ovoid to spheric.
Stems

1, erect, straight, often reddish, simple, glabrous or glabrescent to sparsely villous proximally, villous distally.

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

Leaves

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.

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

± densely villous;

bracts 0–2, sometimes subtending heads.

slender, villous;

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

Involucres

campanulate, 5.5–9 mm, shorter than pappi.

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

Ray florets

13–30;

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

(5–)8–14;

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

Disc florets

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.

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

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.

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

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

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

Cypselae

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.

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

= 18.

= 18.

Eurybia radula

Eurybia compacta

Phenology Flowering late summer–early fall. Flowering midsummer–early fall.
Habitat Fens, sphagnum bogs, lake and creek shores, edges of or openings in wet spruce or tamarack forests, open boggy woods, ± wet meadows, ditches Dry, sandy places, dry to moist pinelands, oak-thickets, bogs, barrens
Elevation 0–600+ m (0–2000+ ft) 0–200 m (0–700 ft)
Distribution
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]
from FNA
DE; GA; MD; NC; NJ; SC; VA
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

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. 371. 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. paludosa, 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 radula, Aster radula var. strictus Aster gracilis, Aster surculosus var. gracilis
Name authority (Aiton) G. L. Nesom: Phytologia 77: 261. (1995) G. L. Nesom: Phytologia 77: 259. (1995)
Web links