It is most likely to be confused with a closely related species called prickly sow thistle (Sonchus asper), which looks very similar but has more prickly leaves than the sow thistle. The lobes in each ...

Scotch thistle is the most common thistle species in New Zealand with spines on both the leaf surface and margins. Scotch thistle is a biennial weed, so it depends quite heavily on the establishment ...