The vegetation in Badlands National Park is sparse. The arid environment is only conducive to pockets of trees and grasses in shadowed areas plus along water flows as pictured here. The average rainfall is about 16 inches a year. Most of this occurs during quick spring thunderstorms. Now imagine this area covered by a sea nearly 80 million years ago. After it drained away, the climate became humid and tropical about 35 million years ago. The floodplain probably resembled the Florida Everglades. Since then, the climatic conditions have continued to get dryer resulting in today’s barren landscape.