Brought from Africa to the Americas as a food crop for slaves
(Greenwell 1947). Introduced into Florida and other southern states in 1910 by U.S.
Department of Agriculture as a substitute crop for potatoes (Fairchild 1947, Greenwell
1947). Considered an “aggressive weed” in parts of the Southeast by 1974 (Cook et al.
1974). Widely naturalized in Florida along streams, marshy shores, canals, and ditches by
1979 (Godfrey and Wooten 1979). Still promoted as food, feed, and fuel crop for Florida
in 1980s (e.g., O’Hair et al. 1982, Shih and Snyder 1984). Reported as naturalized in
183 public water bodies in 1990 (Schardt and Schmitz 1990); found in 235 public water
bodies by 1994 (Schardt 1997). Forms dense growth along river and lake shores, displacing
native shoreline vegetation (Arridge and Fonteyn 1981, McCann et al. 1996).