Noxious Weeds That Harm Washington State

tansy ragwortDescription: Tansy ragwort is a biennial thatgrows 2-4 feet tall. Young plants form basalrosettes with dark green, ruffled leaves withreddish stems. Mature plants have dark greenleaves with deep lobes rounded at the tip. Daisylikeflowers are dime-sized, yellow with goldencenters, and typically have 13 petals.Impact: Tansy ragwort is toxic to cattle andhorses whether fresh or dry, causing irreversibleliver damage. It spreads aggressively and seedsprolifically, with seeds remaining viable in thesoil for over 10 years.Control: For small patches or isolated plants,hand-pull or dig plants with a shovel before theyflower and discard plants in the trash. Be sureto wear gloves. Do not mow - plants will just reflowerat a height shorter than the mover blade.For large infestations, selective herbicides canbe very effective. Biocontrols (insects that attackthis plant) are also available. Keep animals out ofinfested pastures.W-22Senecio jacobea