Canada Thistle

Mar 21, 2014

Canada thistle (Cirsium arvense)
Credit Oregon State University Research & Extension

3/23/14  &  3/24/14: This week on "Fieldnotes:" "Canada Thistle," by Heather Sarantis.

"Despite its long list of drawbacks, I appreciate Canada thistle. Understanding its spread and growth patterns gives me insight into humans' relationships to the land. You see, while Canada thistle spreads quite easily, it fares especially well in disturbed areas - cultivated lands, cleared forests, roadsides, and cattle pastures. The greater the disturbance, the better the chance of Canada thistle establishing itself. The more contiguous the disturbance, the wider the area that Canada thistle invades. Put simply, the more we disturb the land, the more we are disturbed by what the land produces in response."