County calls on landowners to control tansy ragwort; offers resources to fight infestations

Published 8:30 am Friday, August 12, 2016

Tansy ragwort – a plant that is toxic to horses and other livestock – is now blooming across King County, and the county’s noxious weed program offers a variety of resources to help landowners control this dangerous invader.  

Known for its aggressive growth, bitter-tasting tansy ragwort is typically avoided by animals if it’s alive, but the plant can be inadvertently fed to livestock if it’s been cut and dried with other pasture grass for hay.

Public and private landowners in King County are required to control infestations of tansy ragwort, and the King County Noxious Weed Program can offer advice on the best control methods for specific properties with large infestations.

“The most important action property owners can take when tansy ragwort is present is removing and killing the plants before they go to seed,” said Steven Burke, King County Noxious Weed Program manager. “A single large tansy ragwort plant can produce up to 150,000 seeds that can lie dormant in the soil for up to 15 years.”

Property owners who suspect they have a tansy ragwort infestation on their land are encouraged to alert the King County Noxious Weed Program as soon as possible.

For more information, call (206) 477-9333; or send email to noxious.weeds@kingcounty.gov. Land owners can also contact Sasha Shaw, noxious weed specialist, by calling (206) 477-4824 or sending email to sasha.shaw@kingcounty.gov.