Calamagrostis ÃÂ acutiflora, called feather reed-grass, is a naturally occurring hybrid species of grass in the genus Calamagrostis, occasionally found in Europe and Asia. Its cultivar 'Karl Foerster' has gained the Royal Horticultural Society's Award of Garden Merit.
It is a hybrid of Calamagrostis arundinacea and Calamagrostis epigejos, both widespread Eurasian species.