I will be getting my chicks in about two weeks. I will build a brooder based on many of the excellent ideas shown in this forum. What I would like to know is what is the earliest point where I can move them a tractor coop. They will be the only ones in it. Is it a matter of simply maintaining body heat? I could put a lamp in the tractor until they don't need it anymore. Would they be ok at 1 month? I've never raised chickens before so I'm a newbie at this. Thanks.