This name is a synonym of Arctostaphylos manzanita subsp. roofii (Gankin) P.V.Wells.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Four Seasons 5(2): 24 1976.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:17900-2.
This name was in version 1 of The Plant List, record kew-2647356, and has not been changed.