Movie with forest eating the moon?

Question

I'm trying to remember this movie I watched a while back; I kinda remember it as being pretty good...

It was sorta post-apocalypse, and the moon had been blown up somewhat, but now it had a huge magical-ish forest growing there. I remember this one guy with white hair and this other guy with a tree branch for an arm... I also pretty vividly remember a fight scene with these characters on/near a red train... I'm also pretty sure there was a girl in a pod on the moon... She was important but I can't remember why.

The animation style was, if I remember correctly Anime, and I'm fairly certain the movie ended with the main character "accepting the forest" or something like that...

Any help is appreciated! I'd really like to go and rewatch it if I can!

Edit: I must've watched it around 2010 or 11.. that's a really rough estimate though...

Answer 1

Perhaps 銀色の髪のアギト Gin'iro no Kami no Agito aka Spirits of the Past?

Three hundred years ago, a genetic experiment gone wrong caused the mutation of all forests on Earth. Armed with consciousness, the vegetation sought to destroy all of humankind, and the war that ensued turned the planet into a hellish dystopia.

In the present day, Agito, a young boy, lives with his father in Neutral City—a village maintaining an uneasy truce with the neighboring forest. One day, Agito, on his way to collect water, becomes separated from his friend and stumbles upon a relic of the past: a girl sleeping in a mysterious machine.

Agito awakens the girl, Toola Cm Sacl, and introduces her to the village. But outside forces have ulterior motives for the girl, who holds the key to restore the Earth. Misguided by Shunack, a soldier from the old world hellbent on destroying the forest, Toola follows him despite Agito's warning. Determined to save Toola and unify humankind with the forest, Agito borrows the power of the forest and pursues her.