We have a coop, an enclosable predator-proof run, and a larger outdoor run area. In the coop I use rice hulls. In the smaller predator-proof run I use pine shavings. In the larger outdoor run area I've been putting down straw. I was wondering which is actually better in this large (@ 900 square feet) outdoor run area: the rice straw I've been using, forage hay, or alfalfa hay. I could choose any of it. I suppose I could put down regular hay as an option too but the forage hay has little wheat seed heads they can scratch for. Any opinions about which is best between all of these options? They don't get to free range or forage in grassy areas but I do plant chicken forage materials in different areas of their run to eat.