Dangers

• Excessive plant growth in your lake or pond can make activities such as swimming, boating and fishing unpleasant, if not impossible. Aquatic plants produce oxygen during the day, keeping game fish alive and healthy. At night, however, these plants consume oxygen, often to the extent of killing off desirable game fish.
  
  

Prevention

• Early prevention of plant growth is always easier than removal of advanced infestations. Common prevention techniques include controlling soil erosion, minimizing feeding of fish and birds, preventing animal waste and fertilizer runoff and steep pond embankments.
  
  

Control

• There are many techniques for controlling plant growth. The best choice depends on the type and extent of infestation. Control methods include dredging and deepening the pond, manual or mechanical harvesting, installation of bottom liners and biological or chemical controls. Chemical compounds (herbicides) offer an easy and effective way to control plant growth. But they often safely control only a handful of plant species and can have many downsides, including toxicity, expense and unintentional killing of fish species.