Watch this guy's YT channel - have been for years now. I think what originally caught my attention on his channel was a video specifically about the flora around run-down Oakland urban-industrial areas.

I think I also first found him from his "guerrilla gardening" work in Oakland. I think it was in a median, planting native species on a barren strip of dirt. Something of that nature.

His backstory is really one-of-a-kind. If I recall correctly, he got really into botany because he worked for Union Pacific railroad, and while stopping in a city, would go to the library and checkout different botany books.