Originally Posted by Dustbunny
Here's what I would do...Start in the pasture on the ground and round up a friend or two on foot, maybe with a backpack, a bicycle, walking stick, even carring an umbrella. Let her follow them so she knows what it is and then have them follow her. Start over if she gets frightened. After she gets to where she accepts that, mount and repeat. If you can do this on a trail after pasture practice it would be helpful also. She needs to not feel like prey from something coming up from behind.
Good luck to you.
I agree with Dustbunny....also if you hear a quad or something coming up from behind turn the horse to face it where they can see what is coming....I did that with my mare for awhile and now she's pretty good at not freaking if something comes from behind....