Non-native Species of the Month- Canada Thistle
(Cirsium arvense)
Canada Thistle is an aggressive perennial and easily displaces native vegetation. It can create large stands from creeping rhizomes and produces an over-abundance of seed. Plants grow 2-5 feet tall, and traits for identification include numerous small pink-violet flowers June-August, flower bracts that are spineless and usually spineless stems. Canada Thistle is widespread in Minnesota, found in areas of disturbance such as roadsides, fields, waste areas, and forest margins. Management includes weed whipping repeatedly before seed formation and spring/fall herbicide applications.