Its usual host plant is creeping thistle. The standard English name in its native area is creeping thistle. It was introduced into North America to help control creeping thistle. It is a parasitic plant whose host is normally the creeping thistle. The larvae feed on creeping thistle ("Cirsium arvense"). Recently, a period of overgrazing has resulted in creeping thistle becoming problematic. Though asserted in some literature, creeping thistle does not form rhizomes.