The genesis of all soils is a function of the interactions of climate, organisms, relief, parent material, and time, which are often called the five factors of soil formation. Because temperatures are cooler and precipitation is greater in Canaan Valley (hereafter, the Valley) than in most other parts of West Virginia, the Valley's soils tend to be wetter during most of the year than the soils on similar landscape positions in other parts of the state. Although the Valley's various soils differ in age, have developed on different parent materials, and are found in diverse landscape positions, most are acidic and/or wet. The Valley's soils vary from organic soils in depressions to sandy soils on the surrounding ridges. In the Valley, the common bedrock under the organic soils is Greenbrier Limestone. Mineral soils also formed on the Valley's floodplains and terraces. Many of these soils, especially those on the wet terraces, have slowly permeable, clayey subsoils that formed in alluvium or slack-water deposits. It is consistent that these soils are somewhat poorly, poorly, or very poorly drained. In some areas, residuum or colluvium occur below the water-deposited material; in other areas the soils formed completely within residuum or colluvium. The residual materials weathered in place from limestone, shale, and/or sandstone. The colluvium weathered from the same parent materials, but has moved downslope. The soils on the sideslopes surrounding the Valley formed in shales and sandstone and are normally dryer than the soils of the Valley's floor. However, some of these low-lying soils are moderately well to somewhat poorly drained. Soils on the ridgetops formed in Pottsville Sandstone. Unique soil horizons developed where Picea rubens (Red Spruce) and Tsuga canadensis (Eastern Hemlock) occur. These spodosols are acidic, sandy, and have very low water-holding capacities.