This name is a synonym of Symphyotrichum oblongifolium (Nutt.) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record B16FBE32-B255-4333-B09F-BFCB2D8EE727) with original publication details: 156 1818.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23843-2.
This name was in version 1 of The Plant List, record gcc-117057.