Cirsium arvense

1. A perennial thistle with tap root and extensive creeping root system; grows in patches which can spread quickly; plants are either male or female.
2. Grazing (early season); timed herbicide control with selective Group 4 herbicides; mowing repeatedly to prevent seedset and deplete root reserves; biological controls released but are largely ineffective.
3. Identification Guide for Alberta Invasive Plants
   Weeds of the Prairies
   WeedsBMP App BC – iOS | Android

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