Plants 50-150 cm; caudices short, rhizomes creeping, elongate, thin to thick. Stems 1-3+, erect (angular in cross section, sometimes winged on angles), glabrous or sparsely hairy in arrays. Leaves: basal and proximal cauline abruptly narrowed to long, winged petioles, blades broadly ovate, 100-300 × 40-100 mm, relatively thick, margins serrate, apices acute, abaxially glabrous, adaxially scabrous; distal cauline sessile, blades lanceolate, 50-80 × 15-20 mm, gradually reduced distally, subentire. Heads 25-200, secund, in open, lax, secund, pyramidal, paniculiform arrays, branches ascending to recurved, often elongate with recurved ends. Peduncles 1-4 mm, sparsely hispido-strigose, bracteoles 2-5, lanceolate, grading into phyllaries distally. Involucres 3-4.5 mm. Phyllaries (10-12) in 3-4 series, ovate to linear-ovate, unequal, obtuse. Ray florets 5-12; laminae 1.5-1.7 × 0.5 mm. Disc florets 5-15; corollas 2.8-3 mm, lobes 0.6-1.5 mm. Cypselae (sometimes mottled) 1.5-2 mm, strigillose; pappi 2-3 mm. Solidago patula is readily recognized by the angled stem and the sharkskin-like texture of the adaxial surface of the leaves.
Stems 5-20 dm from a short caudex, glabrous below the rough-puberulent infl, angular at least below; lvs basally disposed, glabrous beneath, strongly scabrous on the upper surface, the lower with somewhat sheathing petiole and elliptic, elliptic-ovate, or elliptic-obovate, sharply toothed blade 8-30 נ4-10 cm, the middle and upper gradually reduced but still generally toothed; infl paniculiform, generally with widely spreading, recurved-secund branches, in smaller plants sometimes narrower, denser, and elongate, but still secund; invol 3-4.5 mm, its bracts acute (especially the outer) to obtuse (especially the inner); rays 5-12; disk-fls 8-23; achenes sparsely hairy; 2n=18. Swamps and wet meadows; Vt. to Wis., s. to Ga., Miss., and Tex. Most of our plants, as described above, belong to var. patula. Southward, from Va. to Ga. and Tex., this gives way to var. strictula Torr. & A. Gray, a smaller plant with smaller, narrower (to 5 or 6 cm wide), less strongly toothed lvs, the upper notably numerous, much reduced, and commonly entire. (S. salicina)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.