Toxic to horses, cattle, and goats. Can poison humans through milk and honey. The toxins accumulate in the body, causing irreversible liver damage and poor health or death, as more is eaten over time. Highest risk is dried, in hay, because the animal will not avoid it then.

Dig up the whole plant including roots; budding and flowering stems are easier to remove than rosettes. Flowers will go to seed after pulling, so bag and discard flower stalks. Do not pull and leave them in the road!  Do not put flowering or seeding stems in yard waste.   Put them in your garbage or a bag to take to Bayview recycle.  They accept invasive plants for free, just drop it off.   All parts of the plant are poisonous, but flowers have the highest concentration of toxins. It is advisable to wear gloves and protective clothing and wash your hands after controlling tansy ragwort.

Due to its toxicity and invasiveness, tansy ragwort is a listed Class B noxious weed in Washington - landowners are required by law to control and prevent the spread of this noxious weed.