What Causes the Cantle to Lift over a Jump?
“Stinkbugging”: The slang term for when the back of the jump saddle comes off the horse’s back significantly, like in this picture.
The natural bascule of a horse over a fence suggests that we can expect some slight lift of the cantle at the pinnacle of the jump.
However, we do not want to see the severity shown in the original picture - this much lift means something is seriously wrong with how the saddle fits the horse.
What causes this to occur to this degree? It all boils down to the TREE POINTS not making good contact with the horse. Remember that the tree points are the legs of your saddle - they need to rest gently, but firmly, along their entire length to keep the saddle stable and secure.
The saddle is TOO WIDE, meaning the tree points do not make contact with the horse’s sides at the bottom of the points. Even if the headplate is the correct shape, having a too-wide tree dramatically lessens the saddle’s stability.
The tree points are too short - therefore they are not able to adequately stabilize the saddle because they do not reach the weight bearing surface of the rib cage. How long your tree points need to be is determined by the height of the horse’s withers. Low withers do not need tree points the same length as a horse with high withers... It is interesting to me that while many performance horses’ withers seem to be getting higher and narrower, many brands’ tree points are being advertised as shorter - which detracts from stability, fit, and safety.
The headplate is the wrong shape for the horse. When the shape is incorrect, the tree points will not articulate correctly with the horse’s sides. Remember that correct tree size means all 3 factors - the TREE POINT WIDTH, TREE POINT LENGTH, and HEADPLATE SHAPE - match the horse’s needs. It’s never “just tree width”.
The rider is using too many pads or shims, which lift the tree points away from the horse’s sides, preventing contact.
”Flexible” tree points. It has been a growing trend to make the bottom 1/3 of the tree points flexible. However, you get the majority of stability from the lower 1/3 of the tree point, so adding a hinge - that moves the tree point away from the horse’s body when the girth is tightened - means the tree point now ends at the hinge. This shortens the tree points and makes them less effective at stabilizing the saddle.
A combination of all the above: For example, a rider “pads up” a too-wide saddle with too-short tree points.
The safest saddle for the rider is one that has tree points that are the correct length and width for the horse and the correct headplate shape. This will almost always prevent abnormal lift of the cantle, and the whole other slew of undesirable movements: rocking, leaning, listing side to side, or falling off the back of the horse completely.