Canada Thistle

Cirsium arvensecanthistle_1

Quick ID:

  • Perennial with purplish pink flowers less that 2.5cm across.
  • Prickly stems and leaves.
  • Extensive creeping rhizome.


  • Deep creeping rhizome that allows it to survive below the cultivation zone.
  • A single plant is capable of producing over 6m of rhizome per year.
  • Stems up to 120cm tall, are leafy and hollow, becoming hairy with age.
  • An individual plant may produce over 40,000 seeds.
  • Seeds are viable in soil for up to 21 years.

How It Got Here:

  • Introduced from France in the late 1700’s.
  • Now found throughout Canada and the northern half of the United States.

How to kill it with Stem Injection:  Cut tops to have 2-4 inches above ground or just inject stem of thistle plant 2-4 inches above ground using Cavity, Hardened, or Shortened Needle and deliver 2mls herbicide in concentrated form.

Reasons for Concern:

  • Canada thistle is an aggresive weed and has the potential to reduce crop yeilds by 100%.
  • The rhizomes are unaffected by cultivation as they grow below normal tillage depths.


  • Calibrate JK1000 to deliver 2mls
  • Cut top stems of Thistle to expose open ends of hollow stems.
  • Put needle into open end and pull trigger delivering herbicide
  • This method is technically labeled as ‘cut-stem’ or ‘cut stump’ 

3 thoughts on “Canada Thistle

  1. Hmm it looks like your blog ate my first comment (it was super long) so I
    guess I’ll just sum it up what I submitted and say,
    I’m thoroughly enjoying your blog. I too am an aspiring blog blogger but
    I’m still new to the whole thing. Do you have any helpful hints for rookie
    blog writers? I’d certainly appreciate it.

  2. I cut stump with injection gun more effective then just spraying?

  3. Is cut stump with injection gun more effective then just spraying?

Leave a Reply

Your email address will not be published. Required fields are marked *

For security, use of Google's reCAPTCHA service is required which is subject to the Google Privacy Policy and Terms of Use.