Ecologie :

Open, still freshwater, pools, slow-flowing streams; open swamps and lakes; backwater of rivers; sometimes in slightly brackish or polluted water; can form floating, sometimes moving, closed meadows to several hundred square meters; on inselbergs and coastal dunes; very invasive, troublesome in dams, rivers, irrigation furrows, etc., declared a pest in certain countries (S. Africa); forming the Lemno paucicostatae-Pistietum stratioitis community; river sides with Azolla, Nymphaea; lakes with Marsilea, Jussiaea repens; 0-1800 m alt. The plant is eaten in time of famine. In lagoons the plant multiplies exceedingly and harbours the larvae of malaria (Anopheles gambica), fide Burkill.