In reply to DR:
Going cow-free works for me, but you need to be strict about it. No dairy and nothing that contains even a bit of cow fat - biscuits and chocolate are out. Milk and cheese from goats or sheep are fine.
After one week on this diet, I went from sandpaper eyes and rivers of snot to minor symptoms. After ten days, zero symptoms - and that was after wading shoulder high through grass in a deciduous wood. The pollen was so thick you could see clouds of it.
When there's no pollen around, I can eat what I want.
Apparently, it doesn't work for everyone, but it's free and it's easy, so you might as well give it a go. But stare at every single piece of food and think, 'Could this have cow in it?'