
24/07/2025
It’s tansy season! 🌼🚫
This invasive w**d is important to identify and remove from your pastures. Tansy, also called tansy ragwort, scientific name Senecio jacobaea, is dangerous to many species, including horses, cattle, and deer.
Tansy is very invasive and we see it all over Lane County right now! This time of year, it is best pulled out by hand as mowing or spraying is **NOT** as effective when it’s in the flowering stage. Make sure to wear gloves when handling this w**d, as the toxic compound known as pyrolizzidine alkaloids can be absorbed through skin.
Place pulled w**ds in trash bags and place in the trash, do not compost – it’s also important to note that wilted plants are **MORE** palatable to animals!
Horses that eat this w**d accumulate the toxin in their liver over time and develop liver disease after years of consumption. This results in chronic weight loss, diarrhea, colic symptoms, or acute neurologic symptoms. In some cases, horses can be off pastures containing this w**d for years and still eventually develop symptoms.
Spray pastures in the spring or fall to kill this w**d and help prevent its spread!