Tansy ragwort is a noxious weed most often found in pastures and hayfields. It is a biennial or short-lived perennial that reproduces through seeds and roots. Tansy is poisonous to livestock and can cause liver damage. Symptoms that may occur after plant consumption include: weakness, high temperature, incoordination and yellow mucous membranes. Currently, there is no known anti-dote for this alkaloid based toxin.

In Eastern Canada, there are four herbicides which list tansy ragwort on their labels as being controlled: Banvel II (dicamba), 2,4-D Amine 600, Milestone (aminopyralid) and Restore II (aminopyralid/2,4-D). It is unclear, from reading each product’s label, which herbicide would be the most effective at managing tansy ragwort. A trial was conducted to evaluate the performance of each herbicide.  

Read the entire report here: Tansy Ragwort Control in Grass Pastures