The Mi Luo Forest wasn't an actual name. It got its name because of its star system's unique appearance. Should one stand at the highest point in the star system, they would be able to view the star system in its entirety. It was in the shape of an enormous tree.
Its planets weren't exactly spherical in shape. Under the rules governing this star system, they had evolved to become tree-shaped entities, big and small. They even had branches and leaves. If one were to extend their spiritual senses outward and do a quick sweep, they might end up with the wrong idea—that there was a patch of forest in the middle of space.
That was how Mi Luo Forest came to be known by that name.