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King County’s noxious weed list has growth spurt with addition of 4 new garden escapees


Noxious weeds can be hazardous to people and animals, harm fish and wildlife habitat, and they can create headaches for landowners big and small.


Noxious weeds can be hazardous to people and animals, harm fish and wildlife habitat, and they can create headaches for landowners big and small.RSZ-giant-hogweed The King County Noxious Weed Control Board meets Jan. 21 in Issaquah to establish the list of weeds that will require particular attention in 2015.


The board meets on Jan. 21 at 3:30 p.m. at the Issaquah Service Center of the King County Library, Public Meeting Room 2A/B, 960 Newport Way NW, Issaquah. Comments on the county weed list can also be submitted by emailing


This year, the Washington State Noxious Weed Board added several new species to the noxious weed list, all of which are ornamental species that are escaping and creating impacts beyond where they were planted: 


These species and other state list changes are described in detail on the state weed board’s What’s New page. Class A species receive the highest priority and control is required statewide. Class C species can be selected at the county level for required control or added to the educational list of non-regulated species.


The board will incorporate changes made to Washington state’s noxious weed list, as required by state law, as well as considering adjustments at the county level.


Each county in Washington must require control of the noxious weeds designated by the state for that county (see the King County website on Weed Lists and Laws for more information). In addition, county weed boards can select additional state-listed noxious weeds for required control.


For instance, the King County Noxious Weed Control Board has selected tansy ragwort for required control in King County in past years due to its impact on livestock and hay production.


According to the state’s noxious weed law, county weed boards can only require control of species listed on the State Noxious Weed List, but they can add other species to the county weed list for educational purposes and to encourage their control where they are having an impact. 


Control is generally only required for noxious weeds that are still limited enough in distribution to allow for effective containment and eradication. For example, the Class A noxious weed garlic mustard has the potential to seriously impact forest health in the county and is spreading on the Cedar River, but is still limited enough that control is possible. This year, the county aims to increase resources to fight garlic mustard’s spread on the river and elsewhere in the county.


For widespread noxious weeds, the county board encourages control through education and technical assistance. Two examples of widespread noxious weeds are English ivy and Scotch broom.


While these two pests can significantly affect habitat, they are too widespread for county-wide control, so the county board instead focuses on outreach and education, encouraging control where feasible and teaching effective control methods.


For more information on the King County weed list and the Washington state noxious weed law, visit under “Weed Lists and Laws,” or contact Sasha Shaw at The public is invited to attend and provide comments or proposals on weed list changes for the year. Comments can also be submitted in advance by email to