The soils of Big Hole Battlefield, Bear Paw Battlefield, and Canyon Creek are dominated by calcification with large deposits of calcium carbonate. Many of the soils in the sagebrush steppe areas consist of alluvial deposits in stream floodplains and windblown sand and loess.
Conifer and alpine meadow soils are relatively shallow, having been formed from a variety of igneous, sedimentary, and metamorphic rocks. The shallowness of the soils does not play a major role in determining forest distribution. Additional soils have been deposited on the foothills from loess and volcanic ash.