Speaking at the recent Cork 2.0 European conference on rural development, Pauli said that the company he chairs, Novamont, now processes 360,000t of thistles at plants converted from former oil refineries. The weed is converted into lubricants, chemicals, plastics and animal feed.

"There is an enormous business model behind it, and the cost price is for free: you don't even need to buy seeds," he told the Irish Farmers Journal. "We are generating €3,700/t of thistles."