"Epichloë amarillans" is found in North America, where it has been identified in many species of grasses, including "Agrostis" "hyemalis", "Agrostis perennans", "Calamagrostis canadensis", "Elymus virginicus", "Sphenopholis" "nitida", "Sphenopholis obtusata", "Sphenopholis" "× pallens" and "Ammophila breviligulata".