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AquaPlant
AquaPlantA Diagnostics Tool for Pond Plants and Algae
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Blue-Green Algae (Cyanobacteria)

Anabaena, Aphanizomenon, and Microcystis spp., ect.

blue-green algae scum on top of a pond
blue green algae scum on top of a pond
Blue green algae growing on top of a pond


What is Blue-green algae?

A group of photosynthetic bacteria

Physical characteristics

  • can be unicellular, filamentous (thin and stringy or hair-like), or colonial
  • buoyant and will form “scum” layer or floating mats on water surface
  • can cause blue, green, brown, or reddish-purple coloration of water

Where does it grow?

Blue-green algae can grow in both marine and freshwater. Most of the harmful algae blooms (HABs) occur in freshwater. Blue-green algae can grow in lakes, ponds, reservoirs, and slow moving streams when environmental conditions are right, such as warm water, abundance of nutrients like phosphorus or nitrogen, and plenty of sunlight.

Cons of Blue-green algae

Blue-green algae produce cyanotoxins as well as taste-and-odor compounds that fowl the water they are found in. The cyanotoxins can pose a serious threat to not only fish but livestock, companion animals, and humans as well.

 

How to manage this plant
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Jun 20: Fish Management Strategies

Jul 18: To Treat or Not to Treat: Late Season Management

Aug 15: Water Quality for Fisheries Management

Sep 19: Common Aquatic Vegetation Management Mistakes

Oct 17: Liming and Clearing Ponds

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Photo Credits: The majority of the aquatic plant line drawings are the copyright of the University of Florida Center for Aquatic Plants (Gainsville). They are used with permission.

Aquatic plant photographs were provided by David Bayne, Jim Davis, Kelly Duffie, Billy Higginbotham, Michael Masser, John Clayton, Chetta Owens, Diane Smith, Joe Snow, Don Steinbach, Bridget Robinson Lassiter and Peter Woods.

You may use these photos, so long as you give credit to AquaPlant.

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