Jim Brandenburg / Thickspike Gayfeather (Liatris pycnostachya) flowering on tallgrass prairie, Crow-Hassan Park Reserve, Minnesota

Jim Brandenburg / Thickspike Gayfeather (Liatris pycnostachya) flowers with eagle-shaped cloud, Touch the Sky Northern Tallgrass Prairie National Wildlife Refuge, Minnesota

Jim Brandenburg / American Bison (Bison bison) herd of adults and calves on tallgrass prairie, South Dakota

Jim Brandenburg / Monarch (Danaus plexippus) butterfly group resting on Thickspike Gayfeather (Liatris pycnostachya) flowers, North America

Jim Brandenburg / American Bison (Bison bison) male walking through tallgrass prairie, South Dakota

Jim Brandenburg / Burrowing Owl (Athene cunicularia) trio peeking out of burrow in tallgrass prairie, South Dakota

Jim Brandenburg / Cloudy sky over tallgrass prairie, Wind Cave National Park, South Dakota

Jim Brandenburg / Prairie burn in Tallgrass Prairie National Preserve, Oklahoma

Jim Brandenburg / Sunset over prairie, Touch the Sky Prairie, Northern Tallgrass Prairie National Wildlife Refuge, Minnesota

Jim Brandenburg / Trees at night, Blue Mounds State Park, Minnesota

Jim Brandenburg / American Bison (Bison bison) herd in grassland, Blue Mounds State Park, Minnesota

Sean Crane / Tallgrass prairie at sunset, Badlands National Park, South Dakota