provide monophyletic support for Solidago given its inclusion of Oligoneuron.

Chromosome counts have proven to be a valuable character in Solidago taxonomy and in elucidating the cytogeographic history of the genus. Similar chromosome counts may indicate close evolutionary relationships, while different chromosome numbers may suggest distant relationships through reproductive isolation. Chromosome counts have been studied extensively in North America; all Solidago species have a base chromosome number of x=9, but the following ploidy