This name is a synonym of Artemisia tridentata subsp. vaseyana (Rydb.) Beetle.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 9B633401-C304-4428-B139-F710AACFE749) with original publication details: Phytologia 55: 8. 1984 8 1984.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:923867-1.
This name was in version 1 of The Plant List, record gcc-71554.