I live in Oregon and it is always raining. I have a coop with a very large run, and it is partially covered during the winter with a tarp. Here's my problem. The mud and yuck. I have tried mulch, which just got covered in poo and mud and im worried about how that will work over a long period of time. Would the poo and mud and mulch just compost itself over time? Now I have very small rock, which really helps with the mud, but is impossible to clean without taking the rocks out, rinsing them all off and returning them...NOT something I want to do twice a year. What do you guys think about this?