Soil Judging Creates Scientists

As a soil judging coach for ISU, I am often asked, “How do you judge soils?” I could answer by succinctly describing the handbook, but that would put you to sleep.  The premise of this article is not to describe soil judging for what it is — but for what it does. I believe that philosophically, soil judging provides an avenue to create cognitive linkages between abstract knowledge from the classroom, the contextual hierarchy of the natural world, and an understanding of the inherent ambiguity of reality. Ultimately, soil judging creates a scientist.

We acquire knowledge through a variety of mediums e.g., hands-on experience, lectures, literature, diagrams, abstract models, equations, music, art, the list goes on. The modes of learning in which we learn are diverse. Moreover, the modes by which we learn best are highly varied among individuals.  Yet, most of our learning occurs in a classroom, guided by a textbook, with our success evaluated by an exam. But how often are scientists taking exams to successfully apply knowledge to reality? Never.

The application of knowledge is strongly tied to the medium in which the information was obtained. In the classroom, that knowledge is largely abstract. It is a compilation of facts, a generalization of rules, an assemblage of categories. Exceptions and caveats are removed to simplify our learning experience and accelerate our assimilation of information. Therefore, we often address real world problems in the same manner. The exceptions are overlooked, the categories are definitive, and the rules are universal.

The pedagogical wizards of the earth sciences are no strangers to the obstacles presented by the classroom setting. And as for soil scientists, we certainly do move mountains to bring the abundant diversity of the earth’s soils to our students. But I shared the same experience as many during undergrad. I remember long drives during 4-hour field trips with maybe an hour of hands-on activities and classroom labs where we fumbled with jars of dirt of unknown origins.

Like us, soils are a product of their environment. We know a lot about people based on their birthplace, culture, family, peers, and faith because they are the foundation of the individual. And with that information, we can predict how people will interact with the world. Similarly, the sediments, the hillslopes, the climate, the flora, and fauna create the soil individual. And the culture of the soil-landscape gives contextual clues into the nature, origin, and distribution of the soil body.

The abstract knowledge for soil judgers is the handbook. They have not seen the soil-landscape through the framework of the handbook, but read it, nonetheless. The handbook describes how to characterize the shape and slope of the soil-landscape and its lithological origins. The soil and its various horizons are described by their morphology, orientation, and depth in the trench, and by the modes of transformation and translocation of the material. The chemical data are given to aid taxonomic classification. The sum of the soil’s parts is extended to interpretation to determine how suitable the soil is for building a basement or septic tank, how much water the soil can hold, or how agriculturally productive the soil is. 

The abstract knowledge however must be synthesized with sensory and contextual knowledge to get the full picture.  The stink of the air next to the low-lying depressional marsh may already give clues to saturated conditions where thick black muck likely exists over a mottled matrix. The judger may look above to the eroded hillside and observe a droughty slope riddled with stones, where much of the fines have washed downward to form a dense-clayey matrix, which they work in their hands.

The synthesis of abstract and contextual knowledge is confounded by the continuity and complexity of soil bodies. The hillslope segments aren’t discrete. The parent materials are often mixed with multiple origins. Boundaries between horizons vary from abrupt to diffuse. The continuity of the soil body does not align with discrete classification criterion. General rules and guidelines that were given break down. Thus, the soil judger is required to make judgment calls, applying what is known to the observed and the unknown.

And when soil judgers recognize the gap between the abstract and reality, the cognitive linkages fuse. They find themselves standing on the shoulders of giants. They recognize that science is a boundless pursuit of the truth and become inspired to continue the mission. They become scientists.