Noxious Weeds

Our mission is to protect citizens, natural resources, and agricultural resources of Thurston County from the detrimental impacts of invasive, noxious weeds.
What are Noxious Weeds?
- Non-native, invasive plants
- Threaten public health, the environment, wildlife, and recreational areas
- Reduce diversity in impacted ecosystems
- Reduce wildlife forage and habitat
- Can be toxic
- Reduce quality of hay, forage, and other agricultural products
- Increase risk and intensity of wildfires
- Increase cost of roads and building maintenance
Common Species Mandated for Control in Thurston County
- Spurge Laurel (Daphne laureola)
- Poison Hemlock (Conium maculatum)
- Wild Chervil (Anthriscus sylvestris)
- Knapweeds (Centaurea spp.)
- Tansy Ragwort (Jacobaea vulgaris)
- Knotweed (Polygonum spp.)
Get Involved!
- Control noxious weeds on your land
- Report infestations when you find them
- Grow native and non-invasive plants in your garden
- Clean vehicles, boats, equipment and tools after each use- especially when entering new water bodies
- Talk to your friends and neighbors about the impacts of noxious weeds and the importance of controlling them
Protecting Pollinators
Treat weeds prior to blooming to minimize negative impacts to bees and other pollinators. If treatment must occur during the blooming period, spray early or late in the day when pollinators are least active. It may be necessary to remove flowers from plants before spraying.
More information on bees and other pollinators:
- WSNWCB Bee
- WSU Honey Bees and Pollinators
- The Xerces Society for Invertebrate Conservation
- Olympia BeeKeeper Association
Integrated Pest Management
Our program is guided by the use of an Integrated Pest Management (IPM) strategy. This approach to pest and vegetation management uses a combination of practices to treat infestations. The use of physical, mechanical, cultural, and biological methods are prioritized to manage noxious weed infestations. If chemical control is necessary, we choose the least toxic product available and always follow instructions on the label.
- To view a summary of the work the Noxious Weeds Program is doing, view our Annual IPM Report!
Containment Ordinance
If you’re grading, putting in utilities for a development, building a new house, or any other land use activities of this nature, click here regarding the Noxious Weed Containment Ordinance and Containment Procedures.