The width of a tree is determined by the measurements at the front of
the saddle. English trees may be narrow, medium, or wide. Western trees
may have regular, semi-QH, QH, full QH, or Arabian bars.
In an English saddle, the width of the saddle can be narrow,
medium/regular, or wide. Each of these describes the angle between the
points. There is a metal "gullet plate" on the tree, at the pommel of
the saddle. The size of this gullet plate determines the angle between
the points.
A narrow saddle has an 86 degree angle.
A medium or regular saddle has a 90 degree angle--a "right angle,"
like the corner of a square.
A wide saddle has a 94 degree angle.
A Western saddle tree has two measurements:
the width of the fork (blue), and
the angle of the bars (red).
Tree Size
Width of Fork
Angle of Bars
Regular
5 3/4" - 6"
90
Semi-QH
6" - 6 1/2"
90
QH (also
Standard QH)
6 1/2" - 6 3/4"
90
Full QH
6 3/4" - 7"
94
Arabian
7 1/4"
86
In both English and Western saddles, the *only* measurements given by
the "tree size" are related to the front. The size describes only the
gullet plate on the English saddle, or the design of the fork on the
Western saddle.
It is important that the space between the panels (English saddle) or
bars (Western saddle) remain relatively the same from the front to the
back. Since there is not a standard measurement which describes the
gullet channel, then each saddle must be examined individually: look at
the channel, and see if the saddle is well-designed.
For more discussion of the gullet channel, see Gullet
Clearance.