Is it possible to place part of a run on an incline? We get lots of rain and don't want the flooring it to wash away and leave a mud bath. I would prefer not to roof the entire run. Other considerations besides erosion? Another option would be to place the coop and a minimum run on the level and provide additional access to a large inclined yard during the day. Will the chickens inevitably turn the entire yard to dust? Or is there a ratio of yard to chicken that will allow some of the grass to live? If some of the grass will remain, then I don't need to worry about erosion. Thanks!