Title from citation instructions. "September 1997"

The database of the Soil Survey Laboratory (SSL), National Soil Survey Center, currently contains analytical data for more than 20,000 pedons of U. S. soils and about 1,100 pedons from other countries. Standard morphological pedon descriptions are available for about 15,000 of these pedons. Partial data for pedons currently being analyzed may be unavailable. Soil fertility measurements, such as those made by Agricultural Experiment Stations, were not made. Most of the data were obtained over the last 40 years. About 3/4 of the data is less than 20 years old. Analytical data for most of the pedons is fairly complete, according to the prevailing view of the research and characterization needs when the pedon was sampled. Generally, the kinds of analyses have increased over time.