Such weeds include reed canary grass ("Phalaris arundinacea"). It was first isolated from "Phalaris arundinacea" (reed canary grass). The larvae feed on various grasses, primarily "Phalaris arundinacea". These invasive plants include the diffuse knapweed ("Centaurea diffusa") and reed canary grass ("Phalaris arundinacea"). "Phalaris arundinacea" is also being trialled as a potential bioenergy crop in Ireland. The study looked at "Sparganium americanum", "Phalaris arundinacea", "Scirpus cyperinus", "Juncus effusus", and "Calamagrostis canadensis". Narrow-leaved Phalaris arundinacea and Calamagrostis canadensis, and non-graminoid herbaceous plants.