Solidago rigida L. is the most widely distributed species in subsect. Ptarmicoidei. It occurs on prairies, oak savannahs and open woods from Alberta to southern New England and south to New Mexico and eastern Georgia. The yellow rayed species is distinguished by its flat-topped inflorescence, multi-veined phyllaries, and flat, ovate upper stem leaves (Semple & Cook 2006 FNA). Three subspecies are recognized based on differences in leaf and phyllary pubescence (Head & Semple 1988). I have recently considered separating off the more glabrous subsp. glabrata as a separate species but decided not to do so after reviewing the reasons for not doing so presented in Heard & Semple (1988). The species includes diploids 2n=18 and tetraploids 2n=18.
Heard, S.B., and J.C. Semple. 1988. The Solidago rigida complex (Compositae: Astereae): a multivariate morphometric analysis and chromosome numbers. Can. J. Bot. 66: 1800-1807.
Last updated 14 November 2013 by J.C. Semple
© 2013 J.C. Semple, including all photographs unless otherwise indicated.