Saddles & Mules
by Garry McClintock
Why can't I use my saddle on my mule?  A lot of times you can. Mules have different backs just like horses do. Mules are half ass horses, without a horse you have no mule. A mules' mother is always a horse that has been bred with a jack ass, and he will breed with anything that is in heat and will allow him to mount her. What we end up with is a lot of different types of backs depending on what the mother is like. The back of the jack ass is usually pretty darn flat, as compared to the horse, that has more "rock" or sway to its' back.
Another feature that is characteristic of a mule and a jack ass, is they are what is called easy-keepers, which means that is doesn't take a whole lot of feed for them to stay fat real easy and if the mule is not ridden a lot, they will stay pretty fat, and we seem to like to see our animals fat. In fact, you can get arrested if they are not kept that way. Our kids can be skinny but our animals have to be fat.
Now if you are lucky enough to have a saddle and it just happens to stay on your mule, ride the heck out of it, and if that means an hour or so in an arena a few times a week, life is good.  However if you get out on the trail quit a bit, and notice the ears of your mule seem to have gotten a little closer than when you started and your reins are suddenly way too long, then quick, find a good place to quietly dismount in a way that your saddle doesn't role under your mule when you try to get off. Your cinch will be loose and your saddle will have slid way forward. Anybody who has ridden much will know what kind of a wreck this can cause.
Don't just run out and buy a britchin' or a crupper to solve the sliding problem, which they will. Let's take a little deeper look at what is going on here so as we can deal with this as it comes up with different animals in different situations.
The first thing that happened was the saddle slid forward. Why did that happen? Well there are a few things going on here. The first thing is that the saddle was probably built for a horse, which means that the bars of the saddle tree were built to accommodate the sway that is in a horses back, instead of  the flatness of the back on a jack ass. Picture the rockers on a rocking chair and you'll see what I mean. You can see this on your mule if you will place your saddle on his back without any padding or cinches, and take look at how it rocks back and forth. Don't put the saddle too far forward onto his shoulder blade or it won't work, and neither will he. The back will settle a little when you ride, so do this before and after you ride, to get the real picture. What happens when you ride is that there is less bearing surface, evenly distributing your weight, over the bar surface as it sets on the back. The tree or saddle will skid along more easily, and move usually forward, but it can go back. The way a saddle with mule bars is different, is the bars are built to have less "rock" in them and are consequently flatter than the bars built for a horse.
A mule can also have a back with withers, like a thoroughbred, or be mutton withered like a burly quarter horse, depending on what the mare was like. What this means to a saddle maker relates to angle that the flatter bars are set to. We can still use thoroughbred or 90 degree, semi-quarter horse at 92 degree, or a full quarter horse at 95 degree, on the mules just like we do on horses. Generally the mules are set to a semi quarter horse angle, with a little more separation between the bars, like 6 ¼ to 6 ½  inches of width, which accommodates the more fleshy or heavier wither area. The big wide flat back mules need a full quarter horse bar angle with 7 inches of width between them. The backs of the mules are just as different as are those of the horses, they are generally flatter like the jack ass who fathered them.
The other thing that needs to be considered is where the cinchas will be located in relation to the size and shape of the belly of the mule. This is called the riggin position of, or, on the saddle. A saddle can have the front cincha way forward in a full position or back to the middle of the seat in a center fire position, or any place in between, we have choices and need to look at what will be best for all intents and purposes. This is where "fat" can get in the way. To understand this a little better, place your saddle on your mule where it is supposed to be, back behind the shoulder blade and not on it, now take a look at where the ring that holds the latigo is located. A full position or Spanish rig is under the horn or a little forward of the horn. This is about as forward as you can get it. Some mules require the cinch here, because the belly fat will push it there anyway. The problem is that you may gall him as he moves and rubs against the cinch and or the buckle. Neoprene can solve the rubbing, but they are slippery and in other positions can move easier than a stranded cinch. If this happens on your mule and the riggin position is more back to the middle of the saddle and consequently the belly, a saddle maker can move the position of the ring to a full position. If you don't the saddle will continue to slide forward to where the cinch wants to come to a rest, in that little hollow spot just back of the leg. This will vary depending on the conformation. The riggin position should be placed directly above this hollow spot to help keep the saddle in place. The saddle may still want to slide forward, up onto the shoulder blade, but this will minimize the movement. This is when you need a crupper or better yet a breeching, because you can hold the cinch as well as the saddle, and breechings add class to the long ears. Any riggin position that places the cinch on the down hill slide of the belly will only cause it to move to where it will stop, gravity, work with it. If you are lucky and have an animal that is more "hound gutted" the cinch will only want to move back towards the tail or stay where you put it and not move. A breast collar is an easy solution.
Over the years I have had an opportunity to spend time with the ranchers of Baja California, where they are just now getting roads and pickup trucks. These hardy mountain folk have used mules and donkeys since Cortez first settled the country, and I  mean literally. This is a steep, rough and sparse desert and their stock will go where the feed is, and rounding them up can get interesting. These are the true Californios who still use the center fire saddle effectively. They place the cinch right in the middle of the belly and crank her down. The cinch is only twelve or maybe fifteen strands, not very wide, and they put them on tight and keep them there. If you were to watch them come off of some of those hillsides, you wouldn't believe they could do it, let alone keep their saddle in place, but sure enough with a center fire saddle and no crupper or breeching, or breast collar, they stay in place. Hard to believe, but true. I think the difference is the fat. Those mules are all muscle and have backbones and withers to help keep the saddles from sliding around. I often use a center fire saddle on our mule and without a breeching the cinch still slides. It's the fat, center fire is the best place for the cinch, because it pulls from both ends of the saddle, which makes the pressure more even on the bars and back, and the cinch pull is around the manure and not the heart and lungs.
Even though the center fire may be theoretically better, it is bound to cause a wreck if it slides. In today's world, your best bet is still the 7/8 double rig, for all intents and purposes and generalities, you can always be safe with a double rig. The back cinch is made to be used, equally as tight or more so than the front cinch. If you don't tighten it, you might as well leave it home. Tighten it up tight, but do it in a round pen at first in case it takes a little getting used to. Let him buck, if he needs to, he'll get the hang of it, without you on his back. Make sure you have a strap between the two cinchas, so they can't move away from each other, forward or back, besides keeping the back cinch out of the flank, it will keep the front one off the leg or shoulder. This should help keep the saddle from moving.
Your best bet is a lot of wet saddle blankets and a little experimentation, padding can often make a bad situation better, get off your animal once in a while and loosen the cinchas and let the back breathe. If the saddle is too tight, it can burn his back even if it does "fit " him well. If you have dry spots, pad around them and see if you can make it better, it's hard to run out and buy a new saddle, because the "trainer" says to. Do what you can and seek the advice of those who have been there, they can help, but in the end it is up to you.
Saddles and mules continue to be a dilemma, but they are generally flatter than horses and saddles with flatter bars are better for their backs, but all are different and need individual attention. Do what you can, but be safe, white spots happen, but aren't the end of the world. If they happen to you and you think your mule is worth less, let me know. I am always in the market for a good mule.