The Lone Wanderer in 2277 is the first one in years to visit the vale. Most are turned away, some are killed when they try to gain entry by force, and others are shot on sight, like raiders. Only select outsiders were permitted to live long enough to enter the Oasis, though it was rare. Although they disdained technology, the Treeminders continued to use firearms, to remain on equal footing with their enemies. As the Oasis grew and nature once again reappeared in the wasteland, the cult confronted the hostility of the wasteland. The control over the cult, exercised by Tree Father and Leaf Mother (Birch and Laurel), with an equal say in its affairs. The Treeminders shun technology in favor of nature, blaming technological progress for all human misery. The cult, the Treeminders, were to be his last line of defense. Birch saw in Harold, not an unfortunate mutant condemned to live out his life as a tree, never again to resume his wasteland travels, but a god. Around 2257, a small cult formed under Birch, dedicated to the worship of Harold. With Harold's mutation progressing further he became the unwilling heart of an oasis in the desolate wastelands. Sheltered by the rock formations in the northern Capital Wasteland, it gained a new lease on life in the 2240s or 50s when Harold found himself overwhelmed by Bob in his travels and laid down roots in this area in what the Treeminders call the Harvest Month (when Bob's seed pods ripen and disperse their seeds, resulting in the creation of new trees, grass, and plants). As the time passed, the sheltered rocky vale was stripped of mining equipment and other installations, with only a handful of artifacts surviving to the 23rd century. The extensive network of caves beneath it was used as an impromptu shelter by the inhabitants of a nearby mining town from the bombs. What is known as the Oasis was once just one of many mines scattered across the landscape of the United States.

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