Showy Goldenrod
Solidago speciosa Nutt. is treated in a narrow sense here based on research done in the Astereae Lab post Flora North America (Semple et al. 2017). In FNA, Semple & Cook (2006) included S. jejunifolia, S. pallida, and S. rigidiuscula within S. speciosa. The showy goldenrod retains its large lower stem leaves through flowering. The fruits are glabrous except for a single populations in southern Maine. The other three species, in the S. speciosa complex have very sparsely to moderately hairy fruits. The species includes two ploidy levels; diploids 2n=18 occur east of the Appalachians; tetraploids 2n=36 occur in and west of the Appalachians and in the northeastern part of the range.
Semple et al. (2017) included S. speciosa in a multivariate analysis with S. hispida and S. sciaphila. Semple and Cook (2022) published a cytogeography maps for S. speciosa and related species.
Semple, J.C., L. Tong, and Y.A. Chong. 2017. Multivariate studies of Solidago subsect. Squarrosae. I. The Solidago speciosa complex (Asteraceae: Astereae). Phytoneuron 2017-18: 1–23.
Semple, J.C., L. Tong, Y. A. Chong and M. Kaddoura. 2017. Multivariate studies of Solidago subsect. Squarrosae. II. The Solidago bicolor –S. hispida complex (Asteraceae: Astereae). Phytoneuron 2017-33: 1–44.
Semple, J.C. and R.E. Cook. 2022. The cytogeography of Solidagosect. Erectae, sect. Villosicarpae, sect. Squarrosae, and sect. Brintonia (Asteraceae: Astereae). Taxonomy 2: 261–278.
Last update 4 July 2022 by J.C. Semple
© 2022 J.C. Semple, including all photographs unless otherwise indicated