IPM1007, Revised November 2009
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.
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