What Does Duckweed Mean? It Is Both an Aquatic Plant and a Symbol of Wandering

Duckweed is a common small floating aquatic plant, named for the way the whole plant floats on the water surface. Its leaves are flat and tiny, and its fine roots hang weakly in the water without taking hold in the mud. It mostly grows in ponds, paddy fields, ditches and other waters with a gentle current. Duckweed multiplies very quickly, and when conditions are suitable it can carpet a stretch of water in no time.

Literally, duckweed refers to this plant itself; but in everyday expression, it is more often extended to symbolize a life of wandering, with no fixed place and no control over one's fate. Because its roots are not anchored in the mud, duckweed can only drift with the water, and people in ancient times used it to describe a life with no fixed home, forever rushing from place to place. The character ping in the idiom "ping shui xiang feng" (a chance meeting) also refers to duckweed, used as a metaphor for strangers meeting by accident.

In agricultural production, duckweed has a certain value. It grows fast and is fairly rich in nutrients, and after being scooped out it can be used as green feed for fish, ducks and other farmed animals; in some places it is also used as green manure. However, when duckweed multiplies too vigorously it shades the water surface, affecting aeration and light penetration in the water body, so in breeding ponds it usually needs to be scooped out appropriately to keep its growth in check.

Many people confuse duckweed with other plants that float on the water surface, such as water hyacinth and Azolla. To tell them apart simply: duckweed is extremely small, often only the size of a fingernail or even smaller, scattered piece by piece on the water surface; water hyacinth has swollen leaf stalks and is clearly much larger; and Azolla is often reddish-brown and covers the water surface in dense patches. Once you know these features, you can roughly identify the floating plants you see on the water.