What is the correct response when a horse refuses to go past a specific object or spot on a trail?

A horse refusing to pass a specific object — a mailbox, a trash can, a tarp on a fence, a mud puddle — is a version of the approach-and-retreat desensitization problem encountered under saddle, and Clinton Anderson's response addresses it as a training and leadership issue rather than simply a fear issue. Anderson's immediate response to a trail refusal is to avoid the most common rider error: turning the horse around and going a different way. Turning away from the obstacle teaches the horse that refusing works — it removes the pressure of the approaching object. Anderson instead keeps the horse oriented toward the obstacle while allowing it to be at whatever distance the horse can manage without complete panic. His technique is to work the horse at the edge of its comfort zone near the obstacle — not at the obstacle itself, but closer than the horse wants to be. He asks the horse to trot or work energetically at this distance, making the area away from the obstacle the place of work and allowing the horse to stand and relax when it faces the obstacle without resistance. Over repetitions, the stand-and-face position becomes more comfortable than the work-while-facing-away position, and the horse begins volunteering to look at the obstacle. As the horse relaxes, he moves closer — never closer than the horse can handle, always working at the horse's threshold rather than past it. He notes that rushing — pushing the horse to the obstacle before it is ready — typically results in the horse spinning, bolting, or rearing, each of which makes the next encounter with that obstacle more difficult. Warwick Schiller adds that the rider's own response to the refusal matters significantly. A rider who tenses, grips, and braces when the horse refuses is communicating alarm that confirms the horse's assessment that the object is dangerous. Maintaining soft, loose, confident body language when the horse is concerned is part of the rider's job in this situation — not just managing the horse's feet.