The Northeast have so much forest because trees need a great deal of water to grow. The Northeast is near the ocean and gets plenty of precipitation all year. For instance, the Northeast have so much forest because it is unpopulated by humans. Humans usually are the cause of the depletion of forests because we use a lot of wood and we cut them down to build buildings.
In addition, the Northeast have so much forest because if the Northeast have so much forests, it means that there aren't a lot of humans there and an animal can't possibly cut down trees because it's their homes.
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