Reed Canarygrass often invades wetlands, moist fields, and other natural areas as a result of disturbance such as ditching and sedimentation. Once established, the species forms dense, monotypic stands, depositing a heavy layer of thatch that suppresses other vegetation. It spreads vegetatively by rhizomes, as well as by production of large amounts of seed. Reed Canarygrass stands have significantly reduced herbaceous plant diversity and soil insect diversity. Carbon and nitrogen sequestration levels in invaded sites are altered. There are indications that a high degree of morphological plasticity in invasive ecotypes contributes to the invasiveness of the species.