Water lettuce (Pistia stratiotes) is declared noxious in the Illawarra District Weeds Authority control area (including Kiama, Shellharbour and Wollongong council areas).
The weed control class is 1. This means that:
“The plant must be eradicated from the land and the land must be kept free of the plant”.
Description: A free floating aquatic plant. Often escapes from aquaria. Looks like a very small open leaved lettuce or cabbage. Leaves pale green. Spreads from stolons which form numerous 'daughter' plants. It has a dense fibrous root system. Very quickly forms dense masses.
Problem: Mats can choke streams. Spread very rapidly and can deoxygenate the water, resulting in fish kills. Water losses increase due to transpiration. Creates a haven for mosquitoes.
Control: Must be reported to the Local Control Authority. Seek their advice.
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