"Natural"
"Existing in or caused by nature; not made or caused by humankind."

The trees in the distance are wild, native plants that mankind had absolutely no hand in their existence. The other trees were hybridized & planted by humans; however, their growth is the work of Nature. The ground cover is a mix of human hybridized & planted grass; along with native wild grasses & other plants; ie, weeds (of which mankind had no hand in their existence). Nature makes everything grow or not grow.

The weather and seasonal change is all Nature. The Clouds in this photo are "natural".

Unless you are in a remote, untouched, totally wild environment, mankind touches a lot of Nature. More so than we often realize. Or viewed another way, Nature touches mankind. It is often hard to totally separate the two.

Although the above scene is not totally without some influence from mankind, I still consider this scene reasonably "Natural".