Answer:
The reason the Kiowas hung a buffalo hide upon the medicine tree in order to fulfill their annual rites was because there were no buffalos available for them to use.
Explanation:
The Kiowas carry out an annual rite known as the Sun Dance. During the rites, they used a buffalo. They hang the head of a buffalo on a medicine tree.
But during the 1887 Sun Dance rite which was the last Sun Dance Kiowa had, they didn't find any buffalos to consummate their rites. Therefore, they hung an old hide skin on the sacred tree.
"The Way to Rainy Mountain" was written by N. Scott Momaday, a Pulitzer Prize winner. The story recounts the journey of the Kiowa's ancestors, how they started in Montana, their way and surrender to United States Calvary, Fort Sill and final resettlement near Rainy Mountain, Oklahoma.