i just finished building a chicken tractor/hoop coop structure for my laying hens. I intend to have them on fresh grass often all summer long. Do I need to now build them a coop for winter, or are they ok in this thing all year round? I have a LONG electric poultry fence that will go around the tractor when they are big enough to not step right through it for daytime foraging and leg stretching purposes. I intend to winterize this with hay bales on the inside, deep mulch method, and greenhouse plastic around the coop instead of a tarp. I personally think this would be fine, and that chickens aren't all that particular given all their needs are met but what do more experienced chicken keepers say? I live in Maine. It is cold and snowy and all that here from about November often through early April. Below is a picture of the chicken tractor. It is 8x12 and about 5 feet tall in the middle.