Natural Hide Suggestions?

My current setup for my hognose is bioactive, and has some cork bark tunnels for hides. Recently I saw here that you need to have hides that are fully enclosed at one end, and so I have been looking to upgrade. Does anyone know of any natural looking hides? Could I just push one end into the dirt? Right now my snake usually just spends time in a little hollow of dirt underneath some cork bark that he excavated somehow.