Duckweed (Lemna minor), an aquatic green, free-floating plant grows in colonies in freshwater locations. The plants form one tiny leaf or frond with a small root. Numerous species of duckweed often grow together in one locations. The large colonies easily invade ponds and other locations with minimal or no wave activity. A large colony of duckweed will cause oxygen depletion and inevitable fish death.
Deciduous duckweed that is kept under control on a pond surface will provide a home and protection to invertebrates. Despite its benefits, the plant should never be allowed to overtake more than half of the pond's surface, so oxygen depletion does not occur.
Ducks and Duckweed
A wide variety of duck species consume duckweed as a regular food. The ducks help the plant to spread to new locations, as it clings to the ducks feathers when they fly away. Seed dispersal also occurs. Fish, beaver and muskrat also feed on duckweed.
Duckweed is often grown in garden pond to help discourage algae formation. It shades the water, which discourages algae growth from happening. Duckweed also benefits the water by absorbing phosphorus and ammonia. The plant also reduces suspended solids.
Duckweed prefers cool temperatures. The most abundant growth occurs during the spring and summer months. If the water recedes significantly duckweed will continue to grow even on moist mud. The plant thrives in a water pH of 4.5 and 7.5.
Buds, known as turions, develop in the fall. The buds sink to the bottom of the pond over the winter and then reemerge in the spring. The plant requires full sunlight or partial shade to grow. In late spring to early fall tiny white flowers often appear on the surface of the duckweed.