| Name | Schoenoplectiella purshiana var. williamsii (Fernald) Hayasaka | 
| Authorship | (Fernald) Hayasaka | 
| Rank | Variety | 
| Placed in | Schoenoplectiella purshiana (Fernald) Lye | 
| Citation | 2012 J. Jap. Bot. 87(3): 183 | 
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Schoenoplectiella purshiana var. williamsii (Fernald) Hayasaka | 
| Identification made in | [no date] (1) | 
