I am making the garden coop and I'm a little unclear as to what would be best under foot for the chickens. The area currently doesn't have grass, just dirt, so it's pretty easy to do most things. I am digging around the coop for the hardware cloth and the post holes. Should I cover the ground with pea gravel? or is something else better? The tree stump will remain in the middle of the coop.. they'll have fun playing queen of the stump I suspect!