Canada Thistle

( Cirsium arvense )

Type	Information
Toxicity	Non-toxic
Control	Cutting or mowing, biological, re-vegetation (competing crops) and herbicide. Contact your County Weed District or local applicator for more information.
Habitat	Wetter habitat or disturbed ground, including ditch banks, overgrazed pastures, tilled fields or abandoned sites
Root	Extensive vertical and creeping horizontal roots
Leaf Shape	Lance-shaped and shallow-lobed and have spines along the edges
Lifespan	Perennial; two years or longer
Priority 2B Weed	Abundant in Montana and widespread in many counties.
Similar Looking Plants	Russian and spotted knapweeds
Important Information	Hard to manage due to extensive nutrient stores and root systems; combine integrated weed management (IWM) for effective control. The root system accounts for much of the re-establishment of the plant.

Executive Office
Montana Weed Control Association, Inc.

Becky Kington
MWCA Executive Director
406-925-0708
mwca@mtweed.org