Nobody really knows what plant roots are doing when they’re at home. Digging up a plant exposes the roots, but destroys the soil’s natural fabric. Information is lost about the intact natural arrangement of the roots and soil. Ditto for studying the roots of plants in pots. In fact, there is no noninvasive field method of determining, in detail, how the root systems of crop plants change over time in response to variations in weather or soil nutrients.