Publication: Leafl. W. Bot. 6: 48. 1950.
selected vouchers: WTU
Notes: FNA20: "Variety exaltatus is the most widespread and variable variety of the species. Eradiate plants of var. exaltatus have been recognized as var. vaseyi; there appears to be no populational integrity to the eradiate condition."
Chambers and Sundberg (2000) note this is very similar to S. hydrophiloides and differs only in the pubescence.