I currently use pine shavings in my nesting boxes. Pine shavings are also used on the flooring of my chicken coop. I am thinking of possibly changing my nesting box bedding over to hay. I always have hay on hand due to my rabbits. I am not really worried about the whole straw(dry) versus hay(wet)debate. Not enough in the nesting boxes for me to believe that potential mold/mildew build up will be an issue. Besides I don't want to have to buy a different product just for nesting boxes. My big concern is the chickens getting impacted crop from eating the hay!!! That's really the only reason why I haven't done the switch over to hay yet. I would also for a couple reasons like to have them trained to laying on hay, for example if I ever need to isolate or move a hen to a different spot she will just look for the little "hay nest" to lay her eggs. I have no issues with them laying in the pine shavings on the floor aside from when they first start to lay and are still figuring the whole where to go lay part. So to those who use hay, have you ever experienced impacted crop? Was the impacted crop due to the consumption of hay? Any good reason not to change over? I'll do alittle poll as to what you all use as nesting box bedding.