The tallgrass prairie once extended over some 140 million acres, from Indiana to Kansas, and from Canada to Texas. The tallgrass prairie - once the largest contiguous ecosystem in North America -is a vast chunk of nearly vanished America, by the most recent estimates, perhaps as little as two percent remains.

Over seventy native grasses are found within Pipestone National Monument. Big Blue Stem, Indian Grass, and Prairie Cordgrass are just a few of the native species thriving in many areas of virgin and restored prairie.