I have had this problem for a couple years. I have a piece of property that used to be lush and green. It was complete with long grasses and lots of shrubbery, then I got chickens. A few years later that lush area is now a brown, muddy poop pit. This year I am planning on growing grasses in there and make it green again. I have tried taking the hens out of that run for awhile in hopes that it will grow back but it isn't. Any ideas? Because I am out of them.