Scotch Thistle (Onopordum acanthium) is native to Eurasia and has become an invasive species in various parts of North America.
Scotch Thistle is considered a problem due to its aggressive growth, rapid spread, and the ability to form dense stands, displacing native vegetation and impacting ecosystems. It is known for its spiny leaves and large size, which can create challenges for grazing animals and reduce the available forage. Effective management strategies for Scotch Thistle involve a combination of preventive measures, early detection, and control methods. Control may include manual removal, cutting, and targeted herbicide application. Integrated pest management practices are often recommended to address the invasive nature of Scotch Thistle. For specific guidance, please refer to the information on the USDA Forest Service website.