Schoenoplectus americanus (Persoon) Volkart ex Schinz & R. Keller
Distribution: Canada to South America
Synonym: Scirpus americanus Persoon
Habitat: Usually brackish, but also inland
Recognition: Stem triangular and smooth (vs. Bolboschoenus). Notch in scales < 0.5 mm; awns mostly < 0.6 mm; distal leaf blade usually shorter than the sheath; culms strongly triangular, the sides often deeply sulcate; bracts without blades (resembling scales). Spikelets sessile.
The other species with a smooth triangular stem, S. pungens, has a notch in the scales > 0.5 mm; awns mostly > 0.5 mm; distal leaf blade usually longer than the sheath.