Overview of Adjustable Saddle Tree Systems
Most riders hope for a comfortable saddle that fits their horses and that they can ride in for years. But the musculature of any horse changes with maturity, training, changes in workload or in riding discipline, so the fit of any saddle on a horse is apt to change, too. A saddle with an adjustable saddle tree (sometimes called an adjustable gullet) could therefore be considered a wise investment for many riders, as it can prevent the need to swap out a saddle as the horse changes. Adjustable tree saddles may be the best choice for riders with young and developing horses, those who work their horses differently according to the season, and those who lease horses or change mounts regularly.

The tree width of a saddle refers to the distance between the points of the tree. These are located at the front of the saddle, just over the horse's shoulders and near the stirrup bar. Tree width is usually referred to in terms such as "narrow" or "wide" or some degree in between. Saddles with adjustable trees can be modified to maintain an optimal width and clearance over the horse's withers as necessary. For example, if the horse gains weight and muscle, his saddle tree may become too narrow and pinch his shoulders. If the horse's workload declines, or sometimes with age, he may lose bulk over the withers and the saddle tree may become too wide and push down on his withers. The angles of saddle tree points also affect saddle fit. For details about saddle fitting, refer to English Saddle Fitting Guidelines.

Most of the adjustable saddles on the market today involve the use of interchangeable steel gullet plates, sold separately or in complete sets, and saddles that can be opened horizontally at the pommel area to allow access to the tree. Shaped basically like a "V," a gullet plate is screwed into place to establish the tree width and the angle of the points.

Note: The term "interchangeable gullet" can be confusing. The gullet of a saddle (sometimes called the channel) runs the length of a saddle between the panels and is intended to allow the horse's spinal processes to work. Interchangeable gullet plates do not affect the width of the rest of the gullet, and for that reason riders should always be sure the gullet of a saddle is neither too wide nor too narrow for their horse's particular conformation.

The newest innovation in adjustable tree systems replaces the need for gullet plates and allows saddle width to be adjusted to almost any width with the use of an Allen (hex) wrench.

Here is an overview of the various types of adjustable saddle trees and interchangeable gullet systems available from Dover Saddlery.

RTF (Rotate To Fit)--The latest saddle tree adjustment system is found in the Circuit Premier Victory Saddle and Circuit Elite Saddle available exclusively from Dover Saddlery. RTF is revolutionary in its ability to allow a rider to change the tree width by fractions of an inch with just a twist of an Allen wrench inserted into a discreet slot located on top of the pommel. No additional tools and no strength are required to make the change. Adjustments are so quick and easy that they can be done while the saddle sits on a horse's back to achieve a precise fit. The system is also durable enough so that one saddle can be adjusted for use on multiple horses throughout the day--perfect for riders with multiple horses.

Genesis Adjustable Tree--Some saddles in the Marcel Toulouse line, including the Annice, Premia, Marielle, Aachen Dressage and Marianne Dressage may be purchased with a Genesis Adjustable Tree. Similar to the RTF System, the Genesis Tree can be adjusted fractionally using an Allen wrench. Access to the tree adjustment mechanism is hidden underneath the saddle pommel, behind a discreet leather flap.

Easy-Change Gullet System®--Available in many saddles from Bates, Wintec and Collegiate, the Easy-Change Gullet System encompasses six color-coded gullet plates ranging from narrow to extra wide, and a gullet gauge. When placed on the horse where the pommel of the saddle should rest, the gullet gauge shows the size gullet plate that is appropriate for the horse. Unless a saddle's product description states otherwise, it comes with the medium gullet plate in place.

To change an Easy-Change gullet plate, unscrew the D-rings located on each side of the pommel. This opens the gullet. Pull apart the Velcro® closure that runs horizontally under the pommel to separate the panels from the pocket points to reveal the gullet plate. Unscrew the two screws located at the ends of the gullet plate and slide the plate out. Place a different gullet plate into location, and hand-tighten the screws on its ends. When the plate is completely lined up, tighten the screws with the screwdriver. Refit the panels into the pocket points, screw the pommel closed, and press the Velcro closure together.

XCH (Xchange) System--Found in saddles in the Ovation and Pessoa lines, this gullet change system is comprised of five color-coded steel gullet plates ranging from narrow to extra wide. Saddles with the XCH System come with the medium plate in place to fit the average horse.

The XCH Gullet System requires the use of a Phillips screwdriver. To change an XCH gullet plate, unscrew the top two screws on either side of the pommel to release the panels from the front of the saddle tree. Pull the panels down and away from the pocket points. Turn the saddle over and free the leather strip that covers the tree, pulling it forward to reveal the gullet plate. Turn the saddle back over and unscrew the bottom two screws on either side of the pommel; this releases the gullet plate from the tree so that you can insert a different gullet. Re-attach the leather strip, slip the tree points back into their pockets, and tighten all four screws.

Thorowgood System--Thorowgood offers saddles with three specific wither profiles (Standard, High Withers and Broadback) in addition to two systems of interchangeable bars that allow riders to fine-tune the width of the saddle tree. The bars are shaped to accommodate the different wither profiles offered in Thorowgood Saddles; Standard and High Withers profiles use a system designated as the "R" bar system. Broadback profiles use the system designated as the "S" bar system.

The Thorowgood System requires the use of an Allen wrench and a socket wrench. To change a Thorowgood gullet bar, turn the saddle over and use the Allen wrench to remove the screws that are located under the pommel. Slide the panels off the points of the saddle tree to reveal the gullet bar, which has four bolts. Unscrew the bolts using the socket wrench to free the gullet bar. Insert a different bar, then insert and hand-tighten the bolts as you fit the bar into place. The alignment marker on the gullet bar should point toward the front of the saddle. When the gullet bar is nestled into place, tighten the bolts with the socket wrench, then fit the panels onto the points of the tree.

For more assistance or to request a catalog, call 1-800-989-1500 to speak with a Dover Saddlery product advisor, or stop by any of our retail stores. Visit DoverSaddlery.com for a complete store listing and the full product offering.

Related Topic:
English Saddle Fitting Guidelines
Advantages of Synthetic and Leather Saddles
Choices in Saddle Panels