Hort. Kew. 3: 213. 1789.
Plants 30–120 cm; caudices branching, sometimes with elongate rhizomes forming new rosettes. Stems 1–10+, erect, glabrous, sometimes sparsely hairy in arrays; usually with fascicles of small leaves in axils of distal leaves. Leaves: basal and proximal cauline tapering gradually to winged petioles, blades oblanceolate to ovate, 100–300 × 20–70 mm, usually multiple lateral nerves pronounced, margins sharply serrate, ciliate, faces glabrous; mid to distal cauline sessile, blades linear-lanceolate, 30–50 × 8–11 mm, reduced distally, margins entire or finely serrate. Heads 60–450, secund, in paniculiform arrays, openly secund-pyramidal with proximal branches spreading-recurved, or as broad as long with proximal branches widely ascending, recurved (elm-tree shaped). Peduncles 1.5–6 mm, glabrous or sparsely strigillose; bracteoles 0–2, linear. Involucres narrowly campanulate, 3–4 mm. Phyllaries in 3–4 series, strongly unequal, outer ovate, acute, inner lanceolate, obtuse. Ray florets 7–12; laminae 2–2.5 × 0.2–0.5 mm. Disc florets 8–15; corollas 2.5–3 mm, lobes 0.5–0.8 mm. Cypselae 0.9–1.5 mm, sparsely strigose; pappi 2.5–3.5 mm. 2n = 18.
Phenology: Flowering Jul–Sep.
Habitat: Open sandy soils, disturbed areas, fields
Elevation: 0–1000+ m
Man., N.B., N.S., Ont., P.E.I., Que., Ala., Ark., Conn., Del., Ga., Ill., Ind., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis.
Several varieties of Solidago juncea have been described; they do not appear to warrant recognition, each grading into the other.