Sparganium angustifolium
 
Narrow-Leaved Bur-Reed

Early Achene

7 km North of Highway 3 on Silica Sands Road, East of Hudson Bay
05-August-2017

I am not convinced of my identification of this specimen. Various authors have subdivided this genus in different ways.  See here for a table of characteristics of species similar to S. angustifolium.  The sources of the information in the table are the Flora of North America and Plants of the Western Boreal Forest & Aspen Parkland.