I've been reading so so much about what others have under their runs; gravel, sand (play/builders) hay, peat moss and dirt, pine shavings, chopped leaves... (I plan to have a corrugated roof over the run) I'm so confused. I will have 1/2" wire underneath the coop also and it'll be on dirt, no grass (not that it would last long anyway). I want to cover the wire but so far everything has issues. Also, is it ok to use pressure treated wood on the bottom frame of the coop? Is it ok for the birds to be near the chemicals in this wood. I think I need it as it will certainly rot if it's regular wood. Thanks for you help!