The use of horses, mules and other equine animals is limited to roadways or to trails designated for such use. Horses and other animals are not to be hitched or tied to trees, shrubs or park facilities in a manner that will cause injury or damage to the plant or facility. Animals may be hitched to trailers for short periods of time for grooming and saddling. Animals must be stabled inside a trailer, at a hitch rail or in stalls or corrals, if provided. Portable stalls, pens or electric fences are not permitted.