Horses set aside certain areas in a pasture. Horses have a lounging area, where the grass is very short, this is where the horse can be seen resting, sunbathing or just taking a nap. Horses also have certain areas where the defecate and a horse will not eat where it has defecated. This is why it is a good idea to harrow a field once in a while to increase the usage of a pasture for horses. Also, horses are sometimes picky eaters and the grass over here tastes better than that grass.