A treeless saddle is simply a saddle without a tree. What is a tree? A saddle tree is a solid, rigid structure around which the leather and padding of the saddle are built. The tree is made so it conforms to the horse’s back and the rider’s seat. Traditionally, saddle trees were made of wood but today, they can be made of materials such as fiberglass combined with metal, plastic and many still, have some wood in their construction. The leather of the saddle is attached to the tree with staples or small nails.
A treeless saddle, however, does not have this solid structure on which the rest of the saddle is built. Treeless saddles come in western, English and trail styles. These types of saddles tend to be more substantial than a simple back pad.
While there might not be a full tree inside a treeless saddle, some may have a flexible fiberglass cantle and pommel. Other types of treeless saddles may have only layers of padding. There are many different makes and models of treeless saddles, so if you are shopping for one, be sure to try out many different types. Just because a saddle is treeless does not mean that it will fit any horse you put it on. Not all treeless saddles fit all horses (or riders) and when purchasing a saddle it is just as important to "try before you buy" as with a traditional Western or English saddle.
Pros and Cons
There are some advantages and disadvantages to riding with a treeless saddle. Many are also very comfortable for the rider. They can be lightweight, which may be important for riders with problems lifting—you are sitting closer to the horse, so you may find you have a better feel for your horse’s back. Some riders like the close contact provided by treeless saddles, while others may find they miss the twist and shape of a traditional saddle as many treeless saddles make you sit wider.
This type of saddle is also great for a horse who is hard to fit. If your horse has a very wide back or uneven shoulders, treeless saddles may be the answer. Treeless saddles can have pressure points, just as traditional saddles do, so you can’t just assume that you are eliminating the possibility of the saddle causing soreness for your horse just because it is treeless. If the stirrups are attached to a single strap, or the girth or cinch has only one point of connection, this may cause a pressure point in that area. Some may transfer the pressure to the underside of the horse's girth area. A well designed treeless saddle will have rigging that distributes pressure, rather than concentrates the pressure on one area of your horse’s body.
One issue with some treeless saddles is that they may not be as secure as a traditional saddle. Because they don’t have a tree to stabilize them may be more inclined to turn, taking you with it. With this type of saddle, it might be wise to use a breastplate (straps that go forward from the front of the saddle around the horse's chest) to help prevent the saddle from turning. If your horse has low withers or a very round or flat back may have to be very careful about the type of treeless saddle you use and how you secure it.