Eriophorum vaginatum
Sheathed Cottongrass

Middle Cauline Leaf Apex, Side B

Greenbush Bog, 20 km West of Hudson Bay, SK on Highway #3

Note the leaf sheath is slightly inflated at the apex.

I had originally identified this species as Eriophorum brachyantherum.  The correct identification was provided by Anna Leighton and I very much appreciate her doing this.  Anna is currently working on the next fascicle that will be published by the Flora of Saskatchewan Association.  That publication (Rushes, Bulrushes and Pondweeds, plus the remaining Monocots of Saskatchewan by Vern Harms, Anna Leighton and Mary Vetter) will cover Eriophorum.