Invasive Species Management
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Our entire community is affected by invasive species.
Invasive species can spread quickly, outcompeting native vegetation, decreasing water quality, and increasing the likelihood of erosion. They can be hazardous to human health, poisonous to livestock, and reduce land productivity.
And they are expensive!
Invasive species can reduce property value and significantly affect timber and agriculture production. It is estimated that Oregon experiences annual losses of over $80 million to personal income from just 25 state-listed noxious weeds. If left to spread, these species could cost an estimated $1.8 billion in annual losses [1].
What are invasive species?
Invasive species are non-native plants and animals that cause environmental or economic harm. Some invasive species were intentionally brought to new regions for practical purposes: to control erosion or to decorate our landscapes as ornamental plants. Others are accidentally introduced to new places by catching a ride on vehicles, boats, or in shipments of goods.
Once outside their original habitat, these species can grow out of control due to the absence of their natural predators and constraints. This allows the introduced species to multiply rapidly and degrade native ecosystems. Invasive species are quick to occupy disturbed areas where plants have been removed and the soil is bare or left uncovered.

Noxious invasive species are particularly damaging.
Noxious species are harmful to humans, livestock, or crops. A species might be considered noxious if it is toxic to touch or ingest, or if it significantly damages a crop. Invasive species that are noxious can be extremely problematic. The Oregon Department of Agriculture maintains a Noxious Weed List and prevents the sale and trading of these particular species in Oregon.
How we can help:
Stopping the spread of invasive species starts with our everyday decisions and actions. Managing invasive species is a community-wide effort.
- Choose non-invasive plants
Be thoughtful about which plants you add to your landscapes. Avoid using invasive plant species, and consider non-invasive alternatives.
Free "non-invasive alternatives" Guide - “Play, Clean, Go!”
Clean your boots, pets, vehicles, and any gear when you play outside. Remember the helpful phrase, “Play, Clean, Go!”
Learn About "Play, Clean, Go!" - "Buy it where you burn it!”
Don’t move firewood from place to place, as it may contain insects that would become invasive in new areas.
Learn More at dontmovefirewood.org - "Clean, Drain, Dry.”
Prevent invasive species from traveling by cleaning, draining, and drying boats, kayaks, and other recreational watercraft.
Learn More from Stop Aquatic Hitchhikers - Learn to identify invasive species
Learn to identify invasive species in your area. Check out our Weed & Pest Directory and then become a trained Tualatin Watershed Weed Watcher!
Check out our Weed & Pest Directory - Report it
Report invasive species to the Oregon Invasive Species Hotline. Keep an eye out for species that can spread quickly, referred to as Early Detection and Rapid Response species.
Learn about "EDRR" species - Manage pests
Practice integrated pest management in your garden, farm, or forest.
Integrated Pest Management
Resources
Learn about invasive species throughout our region:
- 4-County Cooperative Weed Management Area
The 4-County Cooperative Weed Management Area (CWMA) is a partnership of organizations, agencies, and nonprofits dedicated to combating invasive weeds in Clackamas, Clark, Multnomah, and Washington counties.
Visit 4countycwma.org - ODA Noxious Weed Control Program
The ODA Noxious Weed Control Program offers resources to identify and control noxious weeds in the state of Oregon.
Visit oregon.gov - Oregon Invasive Species Council
The Oregon Invasive Species Council coordinated a comprehensive campaign to prevent the introduction of invasive species and eradicate, contain, or manage existing invasive species in Oregon.
Visit oregoninvasivespeciescouncil.org - United States Department of Agriculture
The United States Department of Agriculture’s National Invasive Species Information Center is a gateway to invasive species information, covering federal, state, local, and international resources.
Visit invasivespeciesinfo.gov