I have a coop that has a bare dirt floor run. There is no cover to the run except for the wire on the top. At most I have 4 chickens in the area, and its a large area for that number of hens. There is a small sand box with a roof in the run. I want to put something down on the ground to make the space nicer for the ladies. I think sand would wash away, and they've already got sand in the area. What has worked best for you? I wish I could get some grass in there, but they won't let that happen. I'm in Georgia if it matters. Thanks a bunch!