A recent article on the Horse & Man blog discussed some of the issues involved in horses and bikes using the same trails (as on the Flint Hills Nature Trail and the Landon Nature Trail):
It seems simple enough. Good trail etiquette and safety call for mountain bikers to yield to other users. But when that other user is a horse, some extra precautions are necessary. Why? You could call it the nature of the beast.
The most important thing for a bicyclist to know is that a horse reverts to instinct when it is frightened. As the species developed, survival depended on a good flight response, and that instinct is never far from the surface in a horse. In short, if you spook a horse, it will try to escape. This may include a sudden turn or rearing, which could unseat a rider.
The next important thing to keep in mind is that horses are big and powerful. When you go down and your bike lands on you it’s usually not a big deal. Twelve hundred pounds of horse is another matter.
So it’s very important, for your safety and the equestrian’s, that you not spook a horse. It’s also important, if we are to share trails with equestrians, that we get along.
Here’s a good example of bicyclist yielding to equestrians on the Flint Hills Nature Trail: