Parece que você está descrevendo " Origem: Espíritos do Passado ", um anime de 2006
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Genetic engineering on trees was conducted at a research facility on the Moon to produce trees capable of growing in harsh, arid conditions. The trees gain consciousness, obliterating Earth's civilizations and destroying the Moon. Three hundred years later, Japan is a dystopia covered by the Forest, a huge expanse of sapient trees, and ruled by the tree-like Zruids, which inhabit the planet and control the water supply of both trees and humans. Agito, a young boy, and his father Agashi, as well as his friends Cain and Minka, live in Neutral City, a city carved out of the ruined skyscrapers which acts as both a buffer and a bridge between the Forest and the militaristic nation of Ragna. While the people of Neutral City co-exist peacefully with the trees of the forest, the nation of Ragna aims to destroy the Forest to restore the Earth.
One day, Agito and Cain race each other to see who can get to the water hole at the bottom of the city first. By disturbing the sanctity of the water hole and angering the Zruids, the two boys are separated. After stumbling upon a large machine with cryogenic pods, Agito accidentally revives Toola, a young girl who has been asleep for the past 300 years, and brings her to Neutral City. The Forest is angered by Toola's awakening, since she carries a Raban—a portable personal electronic device, worn as a necklace, that can be used for communication and a variety of other tasks. The Forest fears that she will fall into the hands of Shunack, a soldier of Ragna and also a person from the past who was awakened from sleep, and that he will use her Raban to locate E.S.T.O.C., an "environmental defragmentation system" with the ability to wipe out the Forest and restore human control over the world.
