University of Missouri Extension

IPM1007, Revised November 2009

Practical Weed Science for the Field Scout: Corn and Soybean

Thistle, Canada (Cirsium arvense)

Perennial broadleaf

Canada thistle
 

Canada thistle A perennial from creeping horizontal rhizomes that is generally a weed of no-till cropping systems, pastures, and noncrop areas. Seedlings have dull green thick cotyledons and young leaves that are covered with short hairs. Mature leaves are alternate, irregularly lobed, with spiny margins and without hairs on the upper surface. Flowers are pink or purple, typically 3/4 inch in diameter with spineless bracts beneath unlike musk or bull thistle.

Canada thistle
 

IPM1007, revised November 2009

Wild thing
 

IPM1007 Practical Weed Science for the Field Scout: Corn and Soybean | University of Missouri Extension

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