Grand Teton National Park is home to over one hundred different species of grasses. Grasses make up one of the most widely distributed plant types in existence. Grasses are present in every community in the park from wetlands, to sagebrush flats, to forests, to the alpine zone. Wherever they grow, grasses are an integral element of the ecological tapestry. Grasses are the chief food source for much of the native wildlife: bison, elk, marmots and many insect species. Other animal species use grasses to supplement their diets. Grasses also provide cover and nesting material. Many small mammals, as well as birds, use grasses to build nests and insulate burrows against the severe climate.