Two cowboys and a cowgirl watch a controlled burn on their ranch in the Flint Hills of Kansas.

The tallgrass prairie survives in areas unsuited to plowing, such as this section of the rocky hill country of the Flint Hills, which run north to south through east-central Kansas. Once vast, tallgrass prairie has shrunk to only one to four percent of its former size in North America.

Ranchers replicate natural fires when they burn the prairie every few years to destroy tree seedlings and alien plant species, which preserves the prairie as a grassland.