By 1970, the environment was becoming a huge concern to average Americans (note that the first “Earth Day” was marked in that year) and there was a “Back To Nature” movement taking place within the counter-culture, with young people gathering into communes, living self-sustaining lives.
Jack tapped into these issues and, I suspect, might have visited a Giant Redwood forest (having moved recently to the Left Coast), and his feverish imagination went into overdrive.
Of course, Habitat is a section of the Wild Area, adopted home to the “dropout society” called The Outsiders… But just who built the wooden city… and for what purpose? And what about these rumors of a monstrous “Mountain of Judgment”?
After Supes recovers from being zapped with a Kryptonite Paralyzer Rod and wakes up in Habitat, we learn that Jimmy’s assignment is to find answers to the aforementioned questions.