![Erin Bolster, wrangler, and her horse, Tonk, fended off a grizzly bear chasing a horse carrying a young boy on a trail ride near Glacier National Park on July 30, 2011. (Courtesy photo)](https://thumb.spokesman.com/uO6q6eDqVn9RLDznlEJuDvMVKgE=/600x0/media.spokesman.com/graphics/2018/07/sr-loader.png)
Gutsy griz wrangler and horse on Letterman Show Oct. 11
GREAT OUTDOOR STORIES -- Here's latest update from Erin Bolster, the wrangler who rode her horse to the rescue of a boy being charged by a grizzly bear: The David Letterman Show has postponed her appearance until Oct. 11 so they can bring her hero-horse,…