This name is a synonym of Artemisia ludoviciana subsp. redolens (A.Gray) D.D.Keck.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record A08594A6-24D7-486A-9178-5812692CA4BE) with original publication details: Sida 1 374 1964.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:20695-2.
This name was in version 1 of The Plant List, record gcc-47531.