My chickens are around 5 months old- some heavy birds and some aracaunas and polish as well. Currently they are in a 5' high fence that they can, if they choose, fly out of, even the RIRs and the Wyandottes. We are about to release them into the greater yard where we have 4' fences, and are intending to clip their wings to minimize flight escapes, specifically into the neighboring yards. But others in my household want only a 3' fence around the precious garden. Can people please please tell me if a 3' fence can/will hold back hungry chickens with clipped wings? Also- how much lower should poles in the coop itself be for them to jump onto for roosting? Currently they are 3' off of the ground. Thanks!!