Justin from Lovelock, Nv writes
Tordon RTU Specialty Herbicide is not labeled to control knapweed and should only be used by those familiar with the product and and done so very carefully. Monterey Thistledown or Weedmaster may be a better option for you as they are labeled for the knapweed and easier and safer to use.
Answer last updated on: 07/03/2022