This name is a synonym of Calamagrostis inexpansa A.Gray.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 403398) with original publication details: Rep. U.S. Geogr. Surv., Wheeler 6: 285 1879.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:40606-2.
This name was in version 1 of The Plant List, record kew-403398.