Moses Coulee till, up to thick in places. This glacial till, made up of clay, silt, sand, gravel, cobblestones, and erratic boulders, covers most of the upper coulee. Today Moses Coulee supports an excellent example of a shrub-steppe ecoregion. Vegetation includes sagebrush, rabbitbrush, greasewood, hopsage, bitterbrush, bunchgrass, buckwheat and other vegetation once common to most of the Columbia Plateau. The Nature Conservancy has established the Moses Coulee Preserve, which is a contiguous, intact shrub-steppe habitat. It is located south of Jameson Lake near the head of Moses Coulee. It provide habitat for a rich variety of birds (lazuli bunting, common goldeneye, sage
Grand Coulee wide as Niagara Falls and three times as high. Steamboat Rock high and a in area, now stands as an isolated rise, but for a time it created two cataract. When the falls passed north of Steamboat Rock, it found a granite base beneath the basal flows. Granite lacks the close vertical joints of basalt, was resisted the erosion from the cataract's plunge. It remains as hills on the broad floor of the Coulee. Some gravel-bar deposits are visible along the Route 155. They provide evidence of eddies in the lee of rock shoulders. Dry Falls is at the head