Giant Sedge

Panhandle

Franklin, Gadsden, Jackson, Jefferson, Leon, Okaloosa

North

Clay, Duval, Levy, Nassau, Putnam, St. Johns

Central

Hillsborough, Orange, Pasco, Sarasota

South

Collier, Hendry, Lee

Keys

Monroe

20 of 67 counties, from research-grade iNaturalist observations. They show where people have photographed it, not every place it grows — absence here isn't proof it's absent.