Scientific Name
Poa compressa L.
Common Name(s)
Canada bluegrass, flat-stem bluegrass
Tribe / Family Name
Poeae
Flowering Period
June to August
Symbol
POCO
Description
Canada bluegrass is an introduced cool-season rhizomatous perennial; it reproduces by both seeds and rhizomes. Culms range from 15–60 cm tall; culms are strongly flattened. Its inflorescence is a narrow to open panicle 2–10 cm long and sparse to congested with scabrous branches usually in twos. Spikelets are usually 3–6 mm long, laterally compressed, clustered on short branches, subsessile, 3- to 7-flowered, and unawned. Ligules are up to 3 mm long, membranous, obtuse to truncate, mostly entire, ciliolate, and moderately to densely scabrous.
General Info
This pioneer species can be found along roadsides, campgrounds, and other disturbed sites, riparian areas, open woods and forest edges, wet meadows, foothills, plains, and montane areas.
Similar Species
Canada bluegrass may look similar to other bluegrass (Poa) plants. To distinguish this grass from other bluegrasses, look for the wiry and strongly flattened stems, nodes that are often geniculate, short blades with keeled tips, and absence of basal leaves.
Picture of rhizomatous growth habit.
Inflorescence is a narrow to open-panicle.
Close-up picture of spikelet.
Close-up picture of lemma.
Close-up picture of membranous ligule.
Illustration of Canada bluegrass. USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913. <i>An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols</i>. Charles Scribner's Sons, New York. Vol. 1: 259.
Distribution map of Canada bluegrass. USDA PLANTS Database, 2022.