Scotch thistle is a biennial weed, so it depends quite heavily on the establishment of seed on a regular basis if it is to be found commonly in any particular situation. In contrast, many pasture ...

Winged thistle is a winter annual, which means it generally establishes from seed in autumn ... 2,4-D/dicamba, clopyralid or triclopyr/picloram. Scotch thistle is the most common thistle species in ...