A mow has to be loaded periodically, of course, so all barns are designed with some sort of large door on the upper floor. A contraption known as a bale elevator (a sort of motorized ramp) lifts bales from the ground or a wagon into the mow. The exact style and placement of the mow door varies widely, but in the case of the Sawtelle's barn, it is on the end wall facing the yard, hinged so that it opens outward and located directly above the double-doors on the ground-level entrance. When Edgar swings the mow door open, all that appears before him is open air.
As previously mentioned, the Sawtelle barn and land are modeled after my parents’ farm in central Wisconsin. I’m a suburbanite nowadays, but something about growing up around one particular barn (now torn down and long gone) has left a permanent impression on me. I find myself slowing down when I drive past farms, especially to check out the barn. On a drive through central Wisconsin last week, I found myself oogling barns and weaving all over the (thankfully unoccupied) country road I was on. Eventually I had to stop and take a few pictures just to get it out of my system.