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‘Invasive Species Awareness Week’ spotlights threats to King County’s native flora and fauna


In proclaiming Feb. 21-27 as Invasive Species Awareness Week in King County, Executive Dow Constantine urged residents to learn more about how they can help prevent the spread of non-native species that are harmful to the economy, environment, and recreation resources.


King County is working hard to educate landowners, manage high priorityinvasive_species_awareness invasive species and restore habitats and ecological function to areas damaged by non-native plants, animals and insects. King County Executive Dow Constantine has recognized Feb. 21-27 as Invasive Species Awareness Week in King County.

Invasive species include plants, animals and insects that cause economic or ecological harm to a new environment in which they have been introduced. These introduced species, while beneficial to their home areas, can cause problems in their new environment because predators and other environmental limiting factors do not exist, allowing them to spread at alarming rates.

In King County, nutria, New Zealand mudsnail, gypsy moth, garlic mustard, purple loosestrife, and knotweed are among the wide variety of invasive organisms threaten agricultural productivity, forest health, water quality, fish and wildlife habitat, and property. 

Steven Burke, King County Noxious Weed Control Program manager, noted that the County’s ongoing mission to limit the spread of invasive species requires everyone’s assistance.

“Invasive species and noxious weeds arrive and spread in new environments through human activities, therefore our intervention is required to manage them,” Burke said. “By taking simple actions we can all avoid further harming our resources. Invasive species do not respect fence lines, ownership or property boundaries.”

While many introduced, non-native species do not harm their new environment, some cause severe problems. The United States Department of Agriculture has shown that invasive species cost the U.S. more than $137 billion annually, through crop damage, fisheries reduction, forest health impacts, and management.

The expansion of harmful introduced species is one of the single largest threats to the nation’s natural resources. Invasive species:

• Reduce agricultural production,
• Reduce property values,
• Decrease biodiversity and disrupt ecosystems,
• Displace native species that fish and wildlife require,
• Increase soil erosion and bank failure and clog waterways,
• Increase the severity and frequency of wildfires, and
• Further threaten endangered and rare species.

Since 1996, King County has actively managed noxious weeds, which are legally regulated invasive plant species, seeking to provide benefits to the environment, recreation, public health and economic resources within the county by preventing and minimizing their harmful impacts.
Residents can take simple actions to help prevent the introduction and spread of noxious weeds and invasive species:

• Learn about invasive species and report outbreaks to authorities. Visit the websites of the King County Noxious Weed Control Program or Washington Invasive Species Council or download the WA Invasives mobile app.
• Clean hiking boots, waders, boats and trailers, off-road vehicles and other gear to stop invasive species from hitching a ride to a new location. Learn more about preventing spread at the Washington Invasive Species Council.
• Avoid dumping aquariums or live bait into waterways. Follow directions about disposal of school science kits. Teachers might find information at
• Don't move firewood - instead, buy it where you'll burn it, or gather on site when permitted. Learn more at
• Use forage, hay, mulch that is certified as weed free. Learn more by visiting the Washington Department of Agriculture. Plant only non-invasive plants in your garden, and remove any known invasive plants. Consider planting all native species. Learn more at
• Volunteer as a Citizen Science Invasive Plant Monitor with the Pacific Northwest Invasive Plant Council.
• Volunteer to help remove invasive species from public lands and natural areas. Visit the King County Noxious Weed Control Program to learn more.

For more information about invasive plants and noxious weeds in King County, call 206-477-WEED (7333), or visit Questions or assistance with other invasive species can be directed to the Washington Invasive Species Council at 360-902-3000 or


The King County Noxious Weed Control Program works with county residents and public agencies to prevent and minimize harmful effects of noxious weeds to the environment, recreation, public health, and economic resources in King County. The Noxious Weed Control Program’s Board is composed of community members appointed by the King County Council. Information is available at