Usually, my horses have their halters on when they are out in the field. The halters are leather so that if they get caught on anything, they will break easily. Our theory is that if they get loose, it would be easier for someone to catch them and get them safe if they are already wearing a halter.
John plays an interesting game over the fence with Tim's gelding Daybreak. It usually results in Daybreak tugging at John's halter. I noticed last week that this game has caused a couple of white hairs to appear on the bridge of John's nose. Obviously, Daybreak is pulling a bit harder than he should be.
John goes out without his halter now. His behavior has completely changed.
Usually, John wanders across the field in the morning, picks a hay pile and starts eating. Without his halter on, he lets out some rodeo size bucks, canters around for a few minutes and then goes to eat. At night, when its his turn to come to the gate, he lets out several more rodeo size bucks (this time while standing in place - for those of you who saw him at the start of the Maine rides in October - you have seen these in action, somehow I sat quietly through them). After bucking a few times in place, he quietly comes to the gate and lets me put his halter on.
I've decided that a lack of a halter lets him feel like he is a wild horse, running free. I'm tempted to try it with the girls, but perhaps not all at the same time.