Carex gynocrates
 
Yellow Bog Sedge

Pistillate Spike

Fir River Shelter on Fir River Road, West of Hudson Bay
21-June-2017

Gynocrates: Answers to key questions in Sedges (Carex) of Saskatchewan, Fascicle 3, Flora of Saskatchewan by Anna Leighton leading to this species. The answers are in the order you would normally work through the key. 

Stigmas 2; achenes lenticular. NOT [Stigmas 3; achenes three-sided, occasionally terete, though their shape may be concealed by flattened perigynia.]

Spikes 1 per culm, terminal; spike bracts absent.  NOT [Spikes 2 or more per culm, terminal and lateral; spike bracts present on lateral spikes; lowest spike bracts usually evident, often conspicuous, even in compact heads composed of densely bunched and indistinguishable spikes (except in C. maritima, C. chordorrhiza and C. microptera)]

Spike unisexual (occasionally a staminate spike will have a few pistillate flowers at base); perigynia 3-4 mm long, conspicuously spreading in middle of spike.  NOT [Spike androgynous, staminate portion a short point sticking up from globose pistillate base; perigynia 2-3 (rarely 4) mm long, appressed to spreading.]