Me! I'm allergic to pretty much everything in the barn. Around here the choice of hay is bermuda, which I'm highly allergic to. I keep it at bay with various allergy and asthma medications. Whoever said roundbales were the worst--I agree.
A few months ago I was mucking stalls at a friend's house, and she was using some straw she'd picked up. I don't know what was in that straw, but for the next two days I thought I was going to die. My asthma hadn't been that bad in over 10 years. Needless to say, it was an unpleasant, but necessary reminder to me to be careful.