Perigynium, Adaxial View
Dunnet Regional Park
Note the three stigmas.
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]