Yes vertical, no cross rail?

Did someone else teach your mare to jump? If so, it is possible that when she was learning, she got caught in the cross rails, and was whacked in the legs by a rail. That may make the cross rail scary for her.

If not, maybe try putting her through a jump chute (without a rider) that has two cross rail jumps in it, so that she starts to understand that they aren't going to get her, and she needs to go over it every time. Since she is going through the chute, she only has the option of going over, and won't be able to duck out.

Not quite sure why she wont jump but ill tell you what you can do...

First get 2 extra poles and lay one end of the pole one the edge of the top of the end of the rail (where the top rail attaches to the standard) and do the same thing one the other side. In the end the ext rat poles should have one end on the rail, next to the standard, and the other end on the ground and the other pole the same way on the other side. what this does it makes it to where the horse cant escape the jump.

If she still won't jump, keep the extra poles there, get off the horse and lead her over the jump starting at a walk and if she does good move to a trot and reward her if she does good.

Hope this helped!

Pilot error.

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