Hmmmm.... there is a very big line here I think xD Idk if you've ever seen them but some people do create plants in the shapes of things (not including stuff like bonsai trees) like there was this person I saw years and years ago that made these absolutely stunning decor from plants just by getting it to grow in certain patterns by putting obstacles and making it grow around them (even like outdoor furniture) and that because it is tempered by a person that kind of takes away from the whole natural bit. Same thing with botanists. Photography would be the biggest gray area I think because there is a thin line between taking a picture of a tree then calling it art and capturing the tree in a photograph with meaning/obvious knowledge or expressing it a way others might not have seen themselves, that makes it their aspect. Honestly I think we often as people will create art from nature beautiful as it is on it's own but the source will always be nature, we simply utilize it. If you draw a picture of or photograph nature you see sure you did that but basically you are just copying nature. It's kind of sort of like tracing or copying but no one says "I created this" it's more like "I saw this and turned it into my own form of art." Which is fine because how else would it be shared or one be able express their version of it, but if someone painted a picture of a landscape and said "I just thought this up out of my head" you know for a fact if someone recognized it they'd be like "lol no you got that from x location which is real and natural" which is kind of like plagerism. Technically, there are a lot of artists who draw just to draw, of because it's their job and it's not to just make art that people feel something for, in the same way mother nature is just doing their job, in a damn good way. Also could be argued nature kind of made us so nature true source of all art, lolol jk. Idk it's still a gray area for me. I'm torn but I see it both ways. There is an AI they created who can art, and they asked it to create something unique that it wanted to create and it DID it made something completely original all of it's own. I would call that art too even if human hands didn't create it directly (AI might be gray area for some people). And so it goes on and on xD
I would call photography and people who arrange plants a form of art because it's modified by humans. It's a direct human interaction that produces something that nature itself wouldn't have created otherwise.
I know there are people who draw just to draw, but even then there is a purpose behind those drawings even if some people are not aware. It can be as small as because they are bored or because they're happy, it shows through. I draw just to draw most of the time, like when I draw my characters, but there is actually a purpose behind that: to show off my characters.
You draw your favourite character from an anime/movie/cartoon? It's because you like them. You draw a square? Maybe you're in a math class and you're trying to understand how area works. You draw a stick man? Maybe you're bored and that's what is fun for you to draw, or you're proving to your friend that you "can't draw".
Everything humans do has a purpose, but nature CAN be deemed to "not have a purpose". Or at least, they don't exist for humans. They were created long before we even came to be. That's why I don't think nature is art in the way we think it to be. (But it's still pretty)
But if you believe in god then that is a whole can of worms I don't want to argue about XD It's a valid argument because you believe in whatever you want just don't hurt anyone with those beliefs