) is a species of duckweed in the family Araceae, native to Africa, Asia, Europe, and North America, and naturalised in Australasia and South America. It is also known as Common duckweed.
Lesser Duckweed is a fresh water aquatic plant, found in fresh water ponds and slow-moving streams. It thrives in eutrophic water with high nutrient levels and a pH of 5-9. Common duckweed has 1-3 leaves with a single root, 1-2 cm long, hanging in the water. The plants divide as more leaves grow, to become separate individuals. The light green, oval leaves with 3 veins, are 1-8 mm long, and 0.5-5 cm broad. They have small air pockets to assist floatation. The rarely produced flowers are about 1 mm in diameter, with a cup-shaped membranous scale that contains a single ovule and two stamens. The tiny and 8-15 ribbed seeds are 1 mm long.
Lesser duckweed is rich in protein and fats, and is an important food source for fishes and birds. It is often used as a plant in coldwater, tropical aquaria and also in outdoor ponds. The size of the Lesser duckweed colonies must be closely monitored, due to its rapid growth. Lesser duckweed is also grown as a commercial crop for animal feed, especially for poultry and fish. Harvesting is easy as it only involves surface skimming.
Propagation is mainly by division.
Lesser Duckweed (Lemna minor)