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Noxious Weeds

Knotweed in the Raging RiverNoxious, invasive weeds can choke our streams and lakes and make it hard for fish, birds and wildlife to find food and shelter. Salmon have a difficult time going upstream to spawn when the stream is blocked by noxious weeds. Some weeds are poisonous and can cause rashes, illness or death in livestock or humans. Invasions of weeds have the potential to cause increased erosion and fire hazards, and reductions in recreational opportunities and land values. Managing weeds in aquatic environments such as lakes, streams and marine shorelines present unique challenges. The publications below are presented through WSU Extension. Please contact your county’s weed control board for a list of controlled species, specific weeds issues, and methods recommended for weed control in your area.

Weed ID

Send your weed or plant identification requests to the Weed Identification webpage. Specimens may be submitted as digital images or as physical specimens at no charge by following instructions on this site.

General Weed Information

Nox weed video
Video: Noxious Weeds – Everyone’s Enemy


Aquatic Weeds

  • Aquatic Vegetation Management and Control – A 26-page overview of aquatic vegetation, the importance of water plants; when and how to control vegetation in the water to avoid pollution and harm to other aquatic life. Includes a detailed glossary.
  • Aquatic and Riparian Weeds of the West – A guide to the identification and biology of aquatic weeds in the western United States. A 442 page book available for sale.
  • Aquatic Pest Control – A booklet covering the management of aquatic pests, effects of pesticides and regulations. Used in pesticide training for Washington State Department of Agriculture licensing exams. Available for sale.

Specific Aquatic Weeds