Common Name(s): | Common watermeal, Common wolffia, Watermeal |
Scientific Name: | Wolffia columbiana |
Family: | Lemnaceae |
Growth Traits: | Native, annual, warm season |
Description: The species in this genus represent the smallest flowering plants in the world. The fronds, or leaves, are very small.
A colony of common watermeal looks like green sand floating on top of the water. Common watermeal can completely cover a pond and is typically found with other floating vegetation. It is common in impoundments
that are protected from wind and wave action, which can prevent it from becoming very abundant. When common watermeal covers a pond for a lengthy time, the pond can experience dissolved oxygen problems that can cause a
fish kill. Common watermeal is an important food plant for young wood ducks. |
Chemical Control Options: Flumioxazin, fluridone or penoxsulam. |
Mechanical Control Options: Physically removing common watermeal is only temporarily effective because it has the ability to recover quickly. Removing timber that blocks wind to the south and north of a pond usually allows more wave action, which physically moves common watermeal off a pond and onto the shore when the bank slope is not too steep. |
Biological Control Options: Tilapia generally are only somewhat effective and usually must be restocked annually. |