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

	Stigmas 3; achenes three-sided, occasionally terete, though their shape may be concealed by flattened perigynia; NOT [Stigmas 2; achenes lenticular]
	Spikes 1 per culm, terminal; spike bracts absent; NOT [Spikes 2 or more per culm, terminal and lateral; spike bracts present on lateral spikes (except in Section Phyllostachyae), lowest bract usually evident, often conspicuous].
	Spike androgynous; plants monoecious; perigynia 1-18 per spike; if perigynia pubescent then plants caespitose.  NOT [Spike unisexual; plants dioecious; pistillate spike narrowly cylindrical, 10-30 (40) mm long; perigynia 50-100 per spike; plants rhizomatous with pubescent perigynia]
	Lower pistillate scales not bract-like or leaf-like but similar in size and shape to individual perigynia; NOT [lower pistillate scales resembling green, leaf-like bracts much longer and wider than individual perigynia.  Section Phyllostachyae (C. backii, C. saximontana)]
	Perigynia to 3.5 (4.8) mm long with beak between 0.2 and 0.8 mm long.  NOT [Perigynia either 6-8 mm long with ill-defined beak, or shorter than 3.5 mm and beakless]
	Culms single or a few together from long-creeping rhizomes; pistillate scales narrower with narrow hyaline margins; perigynia glabrous, dark, shiny.  NOT [Culms densely caespitose; pistillate scales almost as wide as long with conspicuous, broad, white-hyaline margins; perigynia puberulent, although sometimes sparsely so and primarily at base of beak]