Island in the Plains
NATURE · HISTORICAL MARKER
Island in the Plains
Keystone, South Dakota
Nature
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Called “Paha Sapa,” or “hills that are black,” by the Oglala Sioux, this forested island rises 4,000 feet above the surrounding plains, and from the prairie these distant hills appear black. Covered with thick stands of ponderosa pine on the hills and Black Hills spruce in the moist valleys, the area is rich in diversity, with approximately 1,000 plant species. Bur oak provides acorns that are an important food source for turkeys, grouse, and deer, and American Indian tribes boiled its bark and roots to help bowel problems. Snowberry, also called buckbrush, is recognized by its white berries in the fall, provides food for grouse, prairie chickens, deer, and elk, and some tribes used its leaves to treat eye irritations. Big bluestem, a perennial grass once dominant on the tallgrass prairie, can be identified by fingered seed heads that look like a turkey foot, and young Indian boys used its stalks to make arrow shafts for shooting practice. The Black Hills bring together western and eastern species such as bur oak and paper birch among pine and aspen, and lush grasslands scattered throughout the hills include big bluestem and green needlegrass.
PHOTOS
Photo: Cosmos Mariner
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Keystone, South Dakota · USA
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