Araceae

Pistia stratiotes

Common Names: Water lettuce

Plant Form: Aquatic mat-forming, floating herb. Size: Up to 30 cm across. Stem: Horizontal runners producing new plants. Leaves: Undivided, widest near end, partly overlapping each other, up to 17 cm long, longitudinally ribbed, softly hairy, with short, inflated stalk. Has an overall lettuce-like appearance. Flowers: Inconspicuous, between leaf bases, whitish-greenish, up to 2 cm wide. Fruit and Seeds: Greenish berry 5-10 mm across. Habitat: Ponds, lagoons, wetlands.

Plants are large when not chewed by insects

Damaged plants are smaller

Forms dense floating mats

Flowers are inconspicuous