Canada Thistle

Cirsium arvense

 Canada thistle infestation in the Devils Elbow Complex Fire area. 

Canada thistle infestation in the Devils Elbow Complex Fire area. 

 Canada thistle spreads by seed and rhizomes. If you look closely at this picture you can see the rhizome underwater. 

Canada thistle spreads by seed and rhizomes. If you look closely at this picture you can see the rhizome underwater. 

Canada thistle is very common throughout areas across the Colville Reservation. It prefers areas where it can keep its roots moist. Biological control agents are available to help control this weed. 

 A new Canada thistle rosette emerges from the soil. 

A new Canada thistle rosette emerges from the soil. 

Please visit NWBC for more information on this weed.