Plants 0-180 cm, caudex or slender rhizomes. Stems 1-5+, glabrous, sparsely strigose in arrays. Leaves: basal petiolate; blades broadly elliptic to ovate, 100-350 × 60-120 mm (including petioles), bases truncate to obtuse, apices acute to acuminate, margins sharply serrate, glabrous; distal cauline blades spreading to ascending, linear-elliptic, 30-50 × 6-15 mm. Heads 25-50+, in elongate, paniculiform arrays, proximal branches recurved-secund, sometimes elongate. Peduncles 1.5-3 mm, glabrate to moderately short hispido-strigose, bracteoles 1-5, linear-lanceolate grading into phyllaries. Involucres campanulate, (4.5-)5-7 mm (much exceeded by pappi). Phyllaries in 3-4 series, linear-lanceolate, strongly unequal. Ray florets 4-9; laminae 4-5 × 1.5-2.5 mm. Disc florets 9-11; corollas 4-5 mm, lobes ca. 1.5 mm. Cypselae (brown, ribs dark brown) 3 mm, sparsely short-strigose; pappi 3-4 mm. 2n = 54.
Flowering Sep-Oct. Sandy soils in xeric places; 0-200 m; Ala., Del., Fla., Ga., Md., N.J., N.C., Pa., S.C., Va.
Solidago tarda requires a more xeric environment than S.arguta; it is found mostly on coastal plains. A. Cronquist (1980, citing G. H. Morton, pers. comm.) noted that some plants from northern Florida and southern Georgia had narrower, basally more tapering proximal leaves; some of those plants were tetraploid. The proper taxonomic status of those plants is uncertain.
Much like S. arguta var. caroliniana, but with well developed, slender, stoloniform rhizomes in addition to the more deep-seated main rhizome or short caudex; lvs glabrous or occasionally strigose, the lower mostly ovate, acute or acuminate, with truncate to obtuse base; upper cauline lvs gradually reduced; 2n=54. In sandy soil in more xeric places than no. 28 [Solidago arguta Aiton]; s. N.J. and se. Pa. to n. Fla. and Ala., mainly on the coastal plain. (S. ludoviciana, in part)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.