horses

As someone who learned to ride as a toddler, I am interested in how the horses played a role in Indian culture. I never stopped to think how the horses would eat the same grass as the buffalo, and would potentially eat all of their food source. But I do have one problem with something mentioned in the article today about the horses. Chase said horses ate the bark off the trees, as part of harming the environment and eating food sources of the buffalo. Horses generally don't eat bark off of trees, unless they are really hungry or there is something wrong with them. I have seen horses do it, but it's not normal. So for that to be used as something the horses did doesn't seem quite right to me.
And we also know and learned about the misconceptions that movies and tv played with the image of the "savage" Indian attacking wagon trains. I remember reading in history books how wagons would circle, and now it seems it all came from tv. But my new question is in the movies, you used to see the Indians riding paint or pinto ponies. As a kid, my friends used to ride paint horses, and I remember the horses names as Apache, Chief, and Comanche. My own horse was named Cherokee (but my uncle was part cherokee.) Is that another myth that was perpetuated by the movies or tv, or was there a particular horse that became popular with the Indians? I can see the latter being true, because there are different types of horses for different types of labor.