Located in Osage County, Oklahoma, about 35 miles west-northwest of Bartlesville and just north of Pawhuska is the largest protected area of tallgrass prairie in the world, the Joseph H. Williams Tallgrass Prairie Preserve. The Great Plains preserve was established in 1989 and managed by The Nature Conservancy. Visitors can enjoy watching bison roam freely over 23,000 of the 39,650 acres of land designated for the nature preserve, as well as spot 300 bird species, over 700 plants, and 80 mammals. And their most recent bison head count totals 2,500! Before the Nature Conservancy purchased the land in 1989, much of it was located within the Barnard Ranch, of which…