Thanks for the replies. How about hazel Brian? We've got hazel everywhere and that seems to survive everything.
The lawn has a barn on one side and a driveway at the top so I think that'll stop it, and a low stone wall on the other which might slow it down (I hope as I've got a young apple, a birch and a buddleia there, which are all the most susceptible!), the fourth edge goes out into the field so apart from an apple tree which is on it's last legs anyway, there's nothing for it there.
The stone wall side is next to the veggie patch. Does it attack root veggies? I haven't seen anything about it.
Anyway, I've decided orchids, as I'd just bought some shrubs to go in there which I'll have to find space for elsewhere now, though one's a young red oak which I might try. The early purples are thriving, so there must be some truth in the fungus loving aspect. I've been reading that introducing other mycorrhiza can help combat it, but which? I'd have thought we had enough other fungi here to compete with it - we get mushrooms, boletus and all sorts growing in the lawn.
I wish I could get hold of a sambucina as I'm sure that would love it there, not many people seem to sell them as they're reputedly difficult - they grow wild not too far away, and we're at 900m high.