How many times have you been told by expert gardeners to break up your dirt clods? Breaking up dirt clods to form loose, fluffy soil can look pleasing and feel good to the touch. But does it helpful for your soil? Dirt clods, also known as “aggregates,” are important building blocks inthe structure of healthy soil. The Slake Test is a visual display of the structure of your soil’s aggregates as well as your soil’s resiliency to erosion and “slaking.”