To undo the damage of previous generation, I improve the soil by natural methods, as nature herself would have done it if man had not interfered. I return the minerals to the topsoil which have been leached into the subsoil by unnecessary irrigation. Trees play a vital role in this process. Their roots reclaim the minerals which were leached from the topsoil to the lower layers. A rich leaf mulch is the most important ingredient of my soil, because it adds the missing nutrients.
Leaves also provide bulk.
Adding large amounts of them makes the soil water-retentive. In my estimation, water retention is the single most beneficial quality of any soil. It keeps plants healthy through a drought, and it keeps them from drowning in times of abundant precipitation. Foster Nature's Variety Nature favors a variety of plants. Most pests thrive on monocultures and starve when faced with a wide selection of plants.