Not only among ecologically oriented farmers, gardeners, and hobby gardeners, but also within the circle of conventionally minded, researching, and working agricultural and horticultural professionals, Rusch has been a term of reference for decades. The doctor and microbiologist Dr. Hans Peter Rusch coined the term "cycle of living substance" as the foundation for all biological thinking and action: "Humans and animals are directly or indirectly dependent on plants, which in turn depend on the soil, to which the remains and excretions of all living beings return, thus closing the cycle of substance and energy in nature." In this book, the author explores microbiology and its crucial role in soil fertility.