this perennial does incredibly well in my yard but I have no idea what it might be. not even sure how it got in my yard. am attaching a picture. plants stand about 3 feet tall. would appreciate any help at all. thanks
It is a species of Dichanthelium, maybe Broadleaf Rosettegrass (Dichanthelium latifolium). As a group, plants in that genus are sometimes called panic grasses because they used to be in the Panicum genus (some botanists have recently argued in favor of lumping them back in).
By the way, the plant has flowers. They just aren't very showy.:)