I know many of us don't know how to best approach horses. I think most of us slow down, but don't know what else to do. Maybe you can ask her for specific advice on how we should handle it. I'm not sure if a literal shout is appropriate vs. normal level talking, etc.
She said to give a "Heads Up!" on approach. On the Greenway I'll holler "On your left!" as I approach walkers and it startles them; however, if I wait till I'm beside them it really spooks them. I'd think whatever kind of warning you give would be appreciated.
It would be good to have more input. Some horses spook easier than others. Some riders take their horses out on busy roads so the horses will get used to various scenarios.
There are horses on Overall. They become skittish regardless of our speed, regardless of whether they are on the road or in the pasture - even when they see us. We slow down (location is also on a hill so slow is natural) & the riders work to control the horses.
My wife who is a horse person said the best thing for bicyclist to do is let the horse rider know that you are there about 4-5 car lengths ahead and move to the other side of the lane.
Bill