Soil of poor structure and fertility is turned up to the surface. Surface chopping and slicing implements, if over-cultivation is avoided, are much less destructive to soil fertility. Good management and such implements can start a cycle of soil improvement. It is certainly not the alleged six or nine inches of top soil, vast quantities of which have been removed by erosion. Some of these minerals gathered by the roots and contained in the ever-falling leaves, twigs and small branches are available continually to improve the soil.
Trees are a part of the fertility of the soil.
Originally, large areas of land when only partly cleared, maintained healthy stock. Now, some years after complete timber destruction, it is unable to support healthy growth without added trace elements such as copper, zinc, cobalt, etc. Implements that tend to separate the whole body of the soil into defined sections are destructive to soil fertility. However, it takes an appreciable time to destroy fertile soil. Now this soil has lost its former structure and its capacity to absorb fertility.