So now that the coup building process is getting close to the end, I am starting to think about building the run. We have a lot of post oaks in the yard (lots...like 300 of em). Post oaks grow very straight, thus the name. The area I plan to build the run is in an opening with trees on three of the sides. I was thinking, I might be able to have a bigger run, by somehow using the trees as some of my posts, rather than having the posts inside of the opening. The trees would all be on the outside of the run, so I wouldn't have to figure out how to seal around the trees at the top of the coop. It would give it a somewhat irregular shape, but that might be cool, if not more difficult to build/layout. I am thinking I may be able to attach 2x4s to the trees and build my run framing off of them. Granted, I may have to remove and reset the boards attached to the trees as they grow, but that wouldn't be too often as these are mostly fully grown trees. Thoughts, concerns? Has anyone else done something like this?