Name: greene Savannah, GA (Sunset 28) (Zone 8b) I have no use for internet bullies!
This is merely a guess. The serrated margin reminded me of the Pampas Grass that likes to cut my skin.
Maybe you have some type of tripsacum? Maybe T. dactyloides/fakahatchee grass or something similar?
Sunset Zone 28, AHS Heat Zone 9, USDA zone 8b~"Leaf of Faith"