In this photo Lydia Fitzgerald, Integrated Conservation Agronomist with Virginia Tech and USDA-Natural Resourc
e Conservation Service (NRCS), is demonstrating the importance of good soil structure by comparing two chunks of soil and looking at how they hold together in water. One soil is from an agricultural field that was not disturbed by tillage and another was from a highly tilled field. As seen in the picture, the soil that from the tilled field falls apart, making it more vulnerable to erosion. Tillage and other forms of disturbance minimize biological activity, organic matter, and biotic glues that hold the soil together.
Check out a video of this demonstration by Ray Archuleta, Certified Professional Soil Scientist with the Soil Science Society of America and NRCS: https://vimeo.com/289272435