However, it also feeds on several introduced species, including Capeweed (Arctotheca calendula), Scotch Thistle (Onopordum acanthium), and Lavender (Lavendula officinalis).
In Bulgaria, the collapse of the drying cotton thistle (Onopordum acanthium) stems on which the birds build their nests has caused high mortality; this is thought to be an example of an ecological trap.
Like the thistle, anyone trying to cut it gets a handful of painful barbs.