Rocks of granite deposited by glaciers in the Lamar Valley of Yellowstone National Park by glaciers, are called glacial erratics, and serve as nursery rocks to Douglas fir trees.

Traveling North of 60 … We used a guide service to help us find the best wildlife shots in Yellowstone, and yesterday’s excursion came with a great grizzly encounter. Our guide spotted a grizzly sow and her two yearling cubs on a hillside to the…