Watermeal

Floating Leaf Plants

Wolffia columbiana:

Watermeal

Wolffia columbiana Karst: Watermeal. Lemnaceae (duckweed family). 

Native perennial. This light-green floating, rootless, plant is smaller than the duckweeds (Lemna spp.); it can cover areas of still water and may be mistaken for algae. The leaves are broadly oval, with a flattened, unridged, surface. They are 0.05 in (1.5 mm) wide/long; 25 - 50 leaves can fit on a drop of water. Plants feel gritty or mealy when rubbed between the fingers. The leaves are uniformly green, unlike other Wolffia species, whose leaves may appear to have lighter and darker areas or scattered white dots. Plants multiply by the growth of new leaves 'budding' from ends of existing leaves. Often found among duckweeds; sometimes in pure stands.