Four critical fit points at the front of the saddle

Have you ever heard another rider ask, “I think my saddle is too tight. Do I need a wider tree?”

The answer may surprise you. Often, the saddle that seems too tight is really too wide, and the saddle that seems too wide is too tight. This sounds contradictory if we think of tree width as the only criterion when fitting the front of the saddle. But the head or front of the saddle – the part from the back of the stirrup bars through the front of the pommel – actually has four critical fit points or angles that must match your horse for the saddle to fit correctly.

The four critical fit areas are:

1)     Head shape (pommel arch)

2)     Tree width

3)     Gullet width

4)     Mouth

In this entry I explain the basics of these four critical fit areas to show how they come together to create a good – or bad – fit.

Synopsis (for those who don’t want to read a lot of stuff)

1) Saddle fitting seems complex, but boils down to matching the different angles of the saddle to the same angles on the horse. This is especially true at the head of the saddle – although we have to understand that the tree width, or angle of, or distance between, the tree points, is just one consideration.

2) If the gullet channel at the stirrup bars is too narrow, the saddle looks too wide, even if the mouth and arch are moderately sized and the tree “width” is correct. This kind of tree perches on the stirrup bar area of the panels and creates pressure points along the withers. (A pressure point is an area of high pressure repeated over time that causes the pain, spasm, tissue-breakdown cycle.)

3) If the gullet channel is appropriately sized for the horse, but the mouth of the saddle is too open, the panels through the stirrup bar area will again cause pressure points. An overly open mouth does not “free the shoulders.” Instead, it creates pressure points at the stirrup bars. These high pressure areas pinch at least four of the seven muscles responsible for holding the shoulder to the horse and helping the protraction and retraction of the front legs.

4)  If the tops of panels at the pommel drop into the back of the horse’s shoulders, the saddle may be too wide, not too tight as some think.

Head Shape (Pommel Arch)

Just like people have different heads shapes, from pointy to pumpkin headed, the front arch of the saddle head comes in a variety of shapes. It is critical to match the right head shape to each horse.A tree maker can use an infinite number of head shapes, but all will tend toward one of these three basic shapes.

  1. An A-frame, such as a saddle we would use on a high-withered horse like a thoroughbred
  2. An upside-down U shape, for a “nicely built” warm blood
  3. A hoop or half-barrel for broad, flatter-withered horses. (Anything from a Morgan to a draft or a big warm blood.)

It is important to match the head of a saddle to the shape of the horse, regardless of tree size. For example, a tall, rangy Ukrainian warm blood with high withers may tend toward a broader A-frame shape, and a saddle with a generous U-shape head will sit too close to the withers. It will not shape well to the muscles behind the shoulders because the broad head does not match the horse’s slimmer angles. On the other hand, a muscular working quarter horse may tend toward a small hoop shape, where even a wide tree standard U-head could perch too high on him.

Tree Width

Trees come in different sizes, such as narrow, medium, wide, and the many sizes in between, such as medium narrow and medium wide. Saddles can even come in really wide sizes, such as extra wide, 2X or even wider. Typically, the angle of the tree points – the structural, weight-bearing parts of the tree that wrap from side-to-side around the top and bottom of the pommel –determines the tree size. Many tree widths are then measured by the distance between the bottoms of the steel plates that are riveted to the underside of the tree points to give them strength. This measurement is usually taken in centimeters and then can be translated by the saddle maker as narrow, medium or wide, etc. as a common reverence for the retail market. Some saddlers will also use width references such as centimeters (29, 31, 33, etc.) or single numbers such as 3, 4, or 5.

Since the saddle industry makes a variety of tree shapes and sizes, similar tree widths may fit differentlyfrom brand-to-brand or model-to-model. So don’t assume, for example, that the medium wide tree in the new saddle will fit the same as the medium wide tree in your old saddle. If you are not sure, have a professional fit it for you.

But the correct tree size or width is just the start of finding the right saddle to fit your horse.

Gullet Channel Width

The gullet channel is the space between the two panels (which sit directly against the horse), running the length of the saddle. In general, the gullet should be wide enough to clear the sides of the horse’s spine by about a half an inch on each side.

If the gullet channel at the back of the head is too narrow, the front of the saddle will perch on and pinch the muscles around the withers behind the shoulders. This occurs regardless of a more open mouth and wider tree size.

A gullet that is too wide will dwarf a horse that has higher, narrower withers—the whole front of the saddle will be unstable.


Some saddle gullet channels have parallel panels, where the right and left panels maintain a roughly even distance between them from front to back, or an angled channel, where the gullet channel becomes continuously wider from the back of the saddle to the front.

Parallel panels have a closed mouth; an open mouth occurs when the gullet channel at the mouth of the saddle is wider than the gullet channel at the back of the stirrup bars.

I measure the saddle’s mouth using my fist. (I know the measure “my fist” is inexact, but start measuring saddle heads this way and develop your own definition.) The gullet channel at the back of the head (the stirrup bar area) will typically range from a very tight fist to a very roomy fist that has a half an inch or more width in addition to your fist. I consider a headto be very open or ‘frogmouth’ if the gullet width is two inches or more in width from the back of the head to the front of the head. A saddle is closed-mouth when the difference is one inch or less. A closed mouth saddle usually has parallel panels, while a frogmouth saddle has angled gullet channels.

Closed mouth saddles will generally sit tight to the back of the scapula on horses that are very uphill to the shoulders, while frogmouth saddles will be too open for horses where the angle of the muscles from the back to the front where the saddle sits is lest acute.

A frogmouth represents the most common saddle-fitting problem. In an attempt to “free the horse’s shoulders,” some in the saddle industry mistakenly create a frogmouth. This causes  the front of the tree (the entire length of the tree points) to flare away from the back of the shoulders, leaving a space along the tree points such that the saddle bears little or no weight along their length, ostensibly leaving the shoulders free to move backward on protraction. This is a mistake because the tree is designed (in theory) to bear weight equally from front to back. If the tree points make little or no contact, the horse has to bear the weight at the front of the saddle elsewhere, typically at the stirrup bars. All of the rider’s weight and pull of the girth at the front of the saddle, therefore, falls on the very small stirrup bar area of the panels. This typically creates pressure points on the horse under the stirrup bars. A pressure point is a tack-related area of high pressure on a horse that is repeated over time. Pressure points cause a pain-spasm-tissue breakdown cycle. This is especially true for spring tree saddles, where the tree has some flex to it. I have stood on the middle of a bare spring tree, before the seat and panels were attached, and when I did so the stirrup bars flexed inward. This flexing may cause the stirrup bars to create tissue-rending pressure points on the horse. I find stirrup bar area pressure points most damaging to fox hunting horses, since their riders may spend long periods standing in the stirrups.

Stirrup bar pressure points, where created by a spring tree or a too-open mouth, cause the horse to lift his head and hollow his back. If we ask the horse to use his back properly, he has to fight against these pressure points, making them worse. Even if we see no overt tissue damage to the hair and skin there is still muscle pain and breakdown more deeply in the tissue. This will lead to suboptimum performance, even in a talented horse.

Leave a Reply