This name is a synonym of Salix planifolia Pursh.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 28300333) with original publication details: Vasc. Pl. Pacific N.W. 2: 63 1964.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:226089-2.
This name was in version 1 of The Plant List, record tro-28300333.