European fern is a poisonous weed that has spread and destroyed many pastures in the northern hemisphere in recent years  A cheap and self-sustaining way to deal with this weed is to introduce the plant's natural enemies
As a result, some scientists have suggested that fern-eating moths from the southern hemisphere could be re-stocked to the northern hemisphere affected by the weed as a way to control fern growth
After the European fern population is reduced, livestock will develop immunity to diseases caused by this weed.