Bitou Bush, Chrysanthemoides monilifera ssp.rotundata
This highly invasive weed was introduced from South Africa to stabilise sand dunes on the east coast of Australia. It is now a serial pest.
Ironically the South Africans imported from Australia, Acacia longifolia for the same purpose.
So now we have a South African plant stabilising dunes in Australia and an Australian plant stabilising dunes in South Africa. Both are costing millions of Dollars / Rand to control. I sometimes despair at our collective stupidity.