Creeping Aster

Eurybia surculosa is of conservation concern in Virginia and Alabama. It is often confused with E. compacta, its close relative from the coastal plains. In states where both are present, it is found only inland in the southern Appalachian Mountains and not on the coastal plains; its larger heads help to differentiate it from E. compacta.

Plants 10–90 cm; in clones and clumps (sometimes with rosettes), eglandular (except pedicels); rhizomes slender, herbaceous becoming woody, scaly. Stems 1–3+, erect, simple, straight, proximally sparsely strigillose to glabrescent, distally strigose or villoso- or hirsuto-strigose. Leaves basal and cauline, firm (only midnerves conspicuous), margins slightly revolute, slightly indurate, entire or sometimes remotely crenulate-serrulate, scabrous, teeth indurate, apices acute to obtuse, indurate, often mucronate, abaxial faces scabrous, adaxial sparsely strigose or glabrous; basal and proximal cauline usually persistent, sometimes withering by flowering (bases often marcescent), petioles sometimes narrowly winged, bases sheathing, blades narrowly elliptic, narrowly ovate, or lanceolate to spatulate, narrowly obovate, or oblanceolate, 13–135 × (2–)6–35 mm (earliest smaller), bases attenuate to cuneate; mid short-winged-petiolate or sessile, blades lance-oblong, lance-elliptic, lanceolate, or oblanceolate, 22–105 × 3–14 mm, gradually reduced distally, bases slightly auriculate-clasping to cuneate or attenuate; distal (arrays) sessile, blades lanceolate to linear, 7–42 × 1–6 mm, abruptly reduced. Heads (1–)3–50(–122+), usually in open or dense, corymbiform arrays, seldom borne singly. Peduncles densely strigose or strigoso-hispid, sometimes sparsely long-stipitate-glandular distally; bracts (0–)1–3(–6), leaflike to phyllary-like (bases indurate), scabrous or sparsely strigose. Involucres cylindro-campanulate, 7–11(–13) mm, shorter than pappi. Phyllaries 35–65 in 4–5 series, oblong (outer) to linear-oblong or seldom linear (inner), strongly unequal, membranous, bases indurate, rounded (outer), dark green zones foliaceous, sometimes slightly dilated, in distal ¹ / 3 – ¹ / 2 (outer) to ¹ / 8 – ¹ / 7 or none and not reaching margins (inner), margins hyaline or sometimes purplish, narrowly scarious, erose, ciliate (scarious parts), ± scabrous (foliaceous parts), sometimes short-stipitate-glandular (innermost), apices spreading to squarrose, obtuse, often dilated (innermost), mucronulate (outer) or apiculate (inner), abaxial faces glabrous or strigillose, both scabrellous on foliaceous parts. Ray florets 13–30; corollas bluish violet, (8–)11.5–15.5 × 1.5–2.3 mm. Disc florets 25–40; corollas pale yellow turning purplish, 5–7.2 mm, slightly ampliate, tubes shorter than funnelform throats, lobes erect, deltate to triangular, 0.75–1.1 mm. Cypselae brown, cylindro-obconic, slightly compressed, 3.2–3.5 mm, ribs 8–10, stramineous, strigillose; pappi of tawny-yellowish to pinkish bristles 5.2–7.1 mm, ± equaling disc corollas. 2n = 36.

Aster surculosus Michaux, Fl. Bor.-Amer. 2: 112. 1803

Eurybia surculosa, commonly known as the creeping aster, is an herbaceous perennial in the family Asteraceae that was previously treated in the genus Aster. It is native to the eastern United States where it is found in sandy soils along the coastal plain, though when E. compacta is also present, it exists farther inland in the southern Appalachian Mountains and the Cumberland Plateau. Although the species is not seriously threatened, it is locally endangered in Virginia and Alabama. The flowers, which have bluish violet ray florets and pale yellow disc florets that eventually turn purplish, emerge in summer and persist into the fall.