CANADA THISTLE

CANADA THISTLE

Cirsium arvense
SUNFLOWER FAMILY (Asteraceae)

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This naturalized perennial is widely established in Eurasia and North Africa as well. The erect, branching stems reach up to 5 feet tall. The leaves are up to 8 inches long; they are lobed with spines, but the leaf surfaces are smooth. Numerous flower heads are clustered at the ends of the branches (A). The pale magenta to purple flower heads are less than 1 inch long and about 1/2 inch wide. Short spines are found on the bracts just below the flowers (B). The flower heads of this thistle are much smaller than those of other thistles found in our two nature centers.

Found in open bottomlands, roadsides, and other waste places, flowering from June through September. In Fontenelle Forest, locally common along Camp Gifford Road near the railroad tracks.

This thistle is considered a noxious weed in Nebraska and extremely troublesome in some parts. Also known as Field Thistle.

The content of NatureSearch is provided by dedicated volunteer Naturalists of Fontenelle Forest who strive to provide the most accurate information available. Contributors of the images retain their copyrights. The point of contact for this page is: Roland Barth.