Great Rift of Idaho, Megafloods Natural and Manmade and on Mars, Niagara of the West, Thousands of Springs States:  Idaho and Wyoming Coordinates: 42 to 45 degrees North, 111 to 115 degrees West There are several distinct areas of this shrub-steppe ecoregion of the Columbia Plateau. For the purposes of this discussion, the ecoregion is subdivided … More Snake-Columbia Shrub-Steppe, Part I: Upper Snake River Plain