A statistical analysis was made of soil strength (cone index, remolding index, and rating cone index), soil moisture, dry density, and per cent saturation for soils classified according to the Unified Soil Classification System (USCS) and U.S. Department of Agriculture (USDA) classification system. Data were obtained during wetseason periods from more than 1300 sites located principally in humid, temperate regions of the United States. Soils of high- and low-topography positions were analyzed for average and high-moisture conditions in the wet season. The information was used to improve an existing scheme for classifying soils according to their trafficability. A comparison of USCS and USDA soil types was made for the 6- to 12-in. layer of soils, and a study was made to compare the type of soil in the 0- to 6-in. layer with the type in the 6- to 12-in. layer of the profile, in USDA terms. (Author).