Study: Yellowstone bison mow, fertilize their own grass
By the Associated Press A study of grazing in Yellowstone National Park found that bison essentially mow and fertilize their own food. This allows them to graze in one area for two to three months during the spring and summer while other hoofed mammals must keep migrating to higher elevations to follow new plant growth. Hundreds of bison grazing in an area stimulates the growth of nutritious grasses,