Scotch Thistles. How my father hated them. They can be quite pretty when in flower though.
They are also known as Spear Thistle, Heraldic Thistle, Cotton Thistle or correctly, Onopordum acanthium Yeah, I pasted that.
Scotch Thistle is a nasty plant with very sharp needles and it can take over a field very quickly as they have this front garden of an empty house. God was not so dumb though. She invented chemical sprays too, and spray them my father did until they were all gone, only ever appearing when the seed from a neighbours plant blew in.