Publication: J. Acad. Nat. Sci. Philadelphia. 7: 32. 1834.
selected vouchers: WTU
Notes: FNA20: "Solidago missouriensis was often introduced along railroad lines farther east. It is a highly variable species. In the east, it can be similar to S. juncea and is not always easily distinguished where ranges overlap. In the west, it can similar to smaller plants of S. spectabilis. It is distinguished from the related species by its usually 3-nerved proximal leaves and the usually thin, elongate rhizomes. Across the prairies the species is known to be diploid only (2n = 18). In the Rocky Mountains, tetraploids (2n = 36) are common, the diploids infrequent.
A number of varieties have been described. Shorter, often larger-headed plants (tetraploids when known) from the Rocky Mountains have been treated as var. missouriensis (including var. extraria). Taller, more leafy-stemmed plants, mostly from the eastern half of the range, but occasionally west to Washington, have been treated as var. fasciculata. Plants from Arizona, Colorado, and New Mexico with long, linear leaves have been treated as var. tenuissima. Larger-headed plants with narrow bracts from prairies west of the Cascades in Oregon and Washington have been treated as var. tolmieana. A. Cronquist (1994) opted not to recognize varieties, noting that all appeared to grade continuously into each other. A detailed study of the species is needed."