Winged thistle looks and behaves very similarly to slender winged thistle (Carduus pycnocephalus), so the two species are commonly confused with each other. Slender winged thistle is more tolerant of ...

New biocontrol agent to mine out thistle Its name might give it away but it’s only hungry for one thing - it’s the Californian thistle stem miner, the latest biological control agent to be ...