by Kathy Welch, Weed Warrior Steering Committee Chair
Bull Thistle is an invasive non-native plant that lives only two years. If we all work together we can make huge progress in reducing the numbers and controlling the spread of this plant in our watershed.
Bull Thistle Only – not it’s Native Plant Look-a-Like! Consult our website for photos of bull thistle and compare with photos of the desirable native, Anderson’s Thistle.
Treating and Disposing – Do it now! While we are past the main growing season, if you see a bull thistle, you can still treat it. When the plant is in the rosette form, remove the top two inches of root, and turn it upside down in a sunny location. If the plant has started to bloom, follow the “Bag and Bake” method:
• Dig plants with flowers or seeds, removing as much root as is practical
• Double bag seeds and flower parts using strong plastic yard waste bags
• Spray plants with dish soap/water solution
• Tie bag and leave out in sun to decompose (up to two months)
• Dispose of in trash
• Do not use “green bags” that are to be used for composting and redistribution
• Watch for regrowth from remaining rootstock and seedlings
Image: Second year plant blooms & dies. Flowers are vase-shaped. Credit: Susie Urie