Need help in identifying movie with a boy who can turn into a tree, and a girl from centuries ago
Origin: Spirits of the Past

I finally Googled "walking volcano anime" and found Origin: Spirits of the Past! 



I kept Googling "ribbon phone", "ribon phone", and kept getting some other anime. I kept thinking it was Nausicaa of the Valley of the Wind, but the art styles were totally different. Maybe I thought it was a Miyazaki film because of the story's environmental message.