Whilst I find both the plant and moth interesting, there is a place for this.
Having just recently become aware of the "ragwort" and all it encompasses, I feel loathe to remove it. However, as I have discovered it on local common land where horses are ridden, I feel it is my duty to help protect these unwary travellers (and dogs) and have reported it to the local council.
Much is the pity to remove the food source of the Cinnabar, but needs are must.