Pretty much think its impossible.After lossing almost half of my free rang flock in one day to hawks a few years go they stay in a run now. Our coop and run is in our horse pasture so the only cover is around the fence line. In other words chickens are sitting ducks. Planting bushes in the pasture for cover wouldnt work cause the horses would eat them. I was thinking of making small little A frame houses and putting a few around for them to run to cover but not sure if it would help and it would look messy. Just seems a shame to keep my flock cooped up all the time. I need a chicken shepard to watch over my flock while out.