Yes I agree about them being on ferns,Bracken being a key place.This year though me and a friend saw loads at the top of Wood Docks,waiting to get on to a host,I dont think there is a particular plant that they will get on,but probably more a case of what they can climb up,the blighters.I saw none on Nettles near the infested Wood Dock that day,I thought that maybe hairy plants were more difficult for them to climb up, or something like that, I really dont know, but I'm sure the answer is not just walking through the nettles then.
