⚠ Version 1 of The Plant List has been superseded.
This name is in version 1.1 of The Plant List, record kew-2616679, with some changes.
This name is a synonym of Asclepias longifolia subsp. hirtella .
The record derives from WCSP (in review) which reports it as a synonym with original publication details: Bull. Torrey Bot. Club 46: 184 1919.
Full publication details for this name can be found in IPNI: urn:lsid:ipni.org:names:1966-2
.