Penny, my 10 month old Rhode Island Red, has a bare patch on her lower back. I first noticed the patch 2 weeks ago but didn't know the cause. Two days ago I caught her digging at it. It's getting worse. She shares a coop and run with 3 Plymouth Rocks (also 10 months) who have shown no similar problems. They all eat Egg Maker and their converted stall always has lots of fresh pine shavings. They free range together whenever weather permits and share 3 nesting boxes. The barn is also occupied by 2 saddlebred horses but I doubt that has anything to do with this. None of her behavior is abnormal aside from the scratching. I will attach pictures as soon as I figure out how. Thank you in advance for any ideas.