Watermeal

Watermeal (Wolffia spp.) is a very tiny (less than 1 millimeter) light green free-floating, rootless plant. In fact, watermeals are the smallest seed-bearing plants in the world. The individual plants are slightly larger than a grain of sand and often resemble blue-green algae blooms from a distance. Watermeal forms a layer on the surface that may cover an entire pond if conditions are calm, and heavy infestations can shade sunlight required for oxygen synthesis and fish productivity. They are often found in association with duckweeds.

Management Options

Mechanical Options

Watermeal can be physically removed from the pond through booming or netting the plant off the surface of the water.

Information on Mechanical Treatment of Aquatic Vegetation

Biological Options

There are no biological control options for watermeal.

Chemical Options

The active ingredients that have been successful in treating watermeal include Flumioxazin (E), Fluridone (G), and Penoxsulam (G). E = excellent; G = good.

Information on Chemical Treatment of Aquatic Vegetation

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