For more information visit Midwest Invasive Species Information Network (MISIN). Canada thistle forms extremely extensive root systems that need to be repeatedly damaged to keep them from growing back ...

Easily recognizable due to its vase-shaped purple flowers with dandelion-like seeds, Canada thistle (Cirsium arvense) is a particularly aggressive invasive plant. Despite its name, Canada thistle ...

rhizomes and root fragments. “Most thistles are biennials that spread only via seed,” Anderson says. “But some thistles, like ...