Soil.not just dirt beneath our feet

Dirt is brown. Soil, however, is a colorful and complex material with fascinating and important component parts. It provides the nourishment for the crops and vegetables that we eat, and we build our roads and cities through it and upon it. There is rich and practical science devoted to soils and their structures.

Soil Surveys

Soil Surveys are documents published every fifty years or so that give us detailed descriptions of the physical and chemical properties of soil. Surveying generally occurs by county and the resulting reports are dense collections of prose, tables, and maps.

Why Revive the Old?

Soil Surveying began in the United States in 1895, with Posey County being the first county in Indiana to be surveyed in 1902. Tippecanoe County was surveyed a few years later and was completed by 1906. At this time, surveying techniques were very rudimentary by today's standards and were very labor and time- intensive. Surveyors dutifully carried their plane tables and alidades with them as they traveled by foot, by horse, and even by bicycle across the counties to sample the soil.

While these early soil surveys can no longer tell us the current state of the land, they can provide historical context for our current understanding of soil. For example, "soil" in 1906 is more acutely defined as "topsoil" today, referring to the uppermost layers that go 2 to 8 inches down. In 1906 soil scientists were just beginning to understand the chemical and physical qualities of soil and if nothing else these historic surveys record the birth of soil science.

Digitizing the 1906 Tippecanoe County Soil Survey

Purdue University Libraries are resurrecting the 1906 Soil Survey of Tippecanoe County, Indiana by creating an online version of the original text and map. We are taking advantage of current technology, too: making not only digital image of the map but also recreating the map as a digital geospatial dataset. This layer can be downloaded and examined within a GIS or other spatially aware system in direct relation to modern GIS data, including much more elaborate modern soil datasets. This can show how land use and development has changed over the past 100 years, but it also gives us a glimpse into the minds of the earliest soil scientist as they developed the techniques of modern soil surveying.