Spikelets 5–8 mm, with 4–10 florets. Lower glumes 1.6–2.4 mm; upper glumes 1.8–2.5 mm, acute; lemmas 2.4–4 mm. 2n = 60.
Glyceria canadensis var. canadensis grows throughout the range of the species. The spikelets bear some resemblance to those of Bromus briziformis, otherwise known as rattlesnake brome, hence the vernacular name “rattlesnake mannagrass”.