The bedding material is laid out inside, usually with corn cobs or cat litter and dust-free wood shavings. But cat litter appears to be dusty from being stomped on, which tends to cause respiratory infections in chipmunks. That's beside the point, after we prepared the litter box, we cleaned up their poop that was pooped outside, into the litter box every day. This is a fire that requires patience as they may poop everywhere.