Chris,
I am assuming that your horse loads in the trailer fine, but has learned to blow out backwards once she’s in. This can be a problem in a ramped or step-up trailer and is quite dangerous, both to your horse and anyone who may happen to be in the way as she blows out of the trailer.
We just filmed an episode of Horse Master on this very subject; it will air on April 1st. Actually, the horse in the show was also very difficult to load and once he was in, he’d blow out backwards like he was shot out of a cannon. Although there are many good techniques used to train a horse to load in a trailer, the technique I prefer not only trains him to load, but also teaches him to back out only on command and in a very controlled fashion.
You’ll need two people, a rope halter and training lead and a training flag. Make sure the trailer you are using is safe and in a good location; without any sharp edges protruding, with good footing and in a clear, but somewhat confined area. I prefer to use a rope halter and long lead (15’ is good) for training purposes, although I wouldn’t haul my horse in a rope halter (I prefer a webbed break-away halter for hauling, for safety and comfort).
One person is leading the horse and controlling his head, always keeping it pointed toward the trailer; the other person is waiting subtly in the background with the flag, prepared to flag anytime the horse backs up and releasing the pressure as soon as the horse moves forward. I do not like any techniques for trailer loading that involve touching the horse in the rear—I want his focus to be forward. And I don’t want to use techniques that physically force him—I want him to make the decision to go in voluntarily.
You don’t ever touch the horse with the flag; it is just the sound and movement that makes him uncomfortable. The person controlling the flag has to have excellent timing and must concentrate fully on the horse’s feet so that the flag starts the instant the horse moves backwards and stops the instant he moves forward.
By using this technique for loading, the horse learns that anytime he tries to backup, there is a scary and uncomfortable thing behind him (the flag waving) and that anytime he goes forward, the scary stimulus goes away. Since backwards is no longer an option for him and the person at his head is preventing him from going right or left, he quickly figures out that the only other option is to go forward and into the trailer. The nice thing about this method is that he won’t blow out backwards because he has learned that backwards is not an option.
You should have practiced your backing and general control on the ground way before working on trailer loading, so that your horse is responsive and controllable. Make sure that once you have presented him to the trailer, he is not allowed to look away at all or go in any direction but straight toward it. Be aware that when the flag starts waving, your horse is likely to lunge forward, so make sure the person leading stays well out of the way and is prepared for the horse to jump forward.
Once the horse has loaded, I’ll usually offer him a bite of grain as a reward and pet him for a few minutes to relax him, then I’ll ask him to back out slowly—one step at a time. Be careful not to pull on him—that will make him want to pull back and blow out backwards; try to keep the lead loose. Ask him for one step back, then ask him to halt and pet him and let him relax; then ask again. Have your flagger ready and if he takes more than one step and starts to blow backwards, flag him forward, let him settle, then ask again for one step, repeating the process until he is out.
It is also helpful for unloading if you can let your horse turn around and walk out forward a few times, so he can understand where he is going; but that is not always possible. It is not natural for a horse to back down something; in fact, in nature, they would rarely back up at all. If he is allowed to walk forward down the ramp or step a few times, he may be more relaxed when you ask him to back down.
The training flag is a great tool for trailer loading and also for motivating a lazy horse to go forward; mental pressure often works better than physical pressure. It is also a useful desensitizing tool, but I will never desensitize a horse to the flag until I know whether or not it will be needed for trailer loading or for getting him to move forward. The flag is a 4’ rigid stick with a plastic or nylon flag on the end. The flag I sell is lightweight and very durable and balances easily in your hand, making it easier to handle than most other flags I have used.
Be sure to watch this episode of Horse Master if you can. I think it is one of the best shows we’ve had so far!
Good luck!
Julie
_________________________________
If you liked this article, Julie suggests the following products to help you continue the work with your horse (or call 800-225-8827 for ordering help):
FTG, vol. 2, Lead Line Leadership: http://www.shop.juliegoodnight.com/shop/trftg2leadlineleadership.html
Goodnight's Quick Clip: http://shop.juliegoodnight.com/shop/bsequickclip.html
Rope Couture, Quality Halters, Training Leads and Leads: http://www.shop.juliegoodnight.com/shopforhorsetrainingtools.html
blog 
youtube 
