Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Disturbed sites, roadsides, edge of agricultural fields, mostly at low elevations.
Flowers: June-September
Origin: Introduced from Eurasia
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Wind
Rhizomatous perennial, also sometimes stoloniferous, the culms erect to decumbent, often to 12 dm. tall.
Sheaths open; ligules truncate to obtuse, 3-6 mm. long, usually lacerate; blades flat or folded, up to 4 mm. broad.
Inflorescence an open panicle 5-30 cm. long, usually purplish, the branches spreading to ascending, bearing spikelets nearly to the base; spikelets 1-flowered, articulate above the glumes; glumes subequal, 2-2.5 mm. long, acute; lemmas 2/3 to 1/2 as long as the glumes, scabrous on the keel, awnless; palea over 1/2 as long as the lemma; lodicules 2, 0.4 mm. long.
Utricle
PNW Herbaria: Specimen records of Agrostis gigantea in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Agrostis gigantea checklist entry
OregonFlora: Agrostis gigantea information
E-Flora BC: Agrostis gigantea atlas page
CalPhotos: Agrostis gigantea photos