Book of the Week: Secrets of Fertile Soils

By Erhard Hennig

Editor’s note: This is an excerpt from Acres U.S.A. original book, Secrets of Fertile Soils, by Erhard Hennig. Copyright 2016, softcover, 200 pages. Regular Price: $24.00. SALE PRICE: $16.80.

According to an old teaching doctrine, the earth consists of a more or less thick topsoil and the ground beneath it. In the topsoil, we are told, minerals are released by the process of weathering, and these serve as the plants’ nutritional supply. Today soil is often still regarded as a lifeless matter, a misconception that results from thinking statically instead of dynamically.

Secrets of Fertile Soils by Erhard Hennig

Experiments ascertained that without humus, plants could only grow with mineral salts. Researchers at the time believed this proved that plants can only take in simple element combinations as ions. This conclusion led to the mineral theory that soil cultivators could simply replace the nutrients crops remove from the soil with mineral salts to support future harvests. Soil was regarded as a kind of nutrient con­tainer. Right up to the present day, the notion of a lifeless soil has to a large extent persisted, and scientists constantly seek to explain pro­cesses in the soil from a measurable point of view.

But in fact our field and garden grounds are dynamic systems that work in some respects like living organisms.

The persistence of the myth of lifeless soil is not surprising when we consider that humans tend to take note only of things we can see with the naked eye, such as earthworms. Only since the development of the electron microscope has it been possible for human beings to glimpse the wonderful world of tiny creatures, microbes, bacteria, and fungi.

Edaphon—The Life Within the Soil

The studies of Raoul Francé (1874–1943) are unforgettable. Francé was the first German researcher to study soil life and in particular the living community within the soil. For the whole complex of soil life he coined the term “edaphon” (from the Greek edaphos, the life within the soil). His book Life in the Soil of our Fields, edited in 1923, garnered great attention.

Today we know that a fertile soil contains inconceivably large num­bers of microbes. In just one gram of the best garden soil, one can find millions of soil organisms, including bacteria, mold fungi, actinomy­cetes, yeast, amoeba, algae, and much more. The following statistics are typical of one gram of fertile soil (according to A. Burges):

  • 2,500 million bacteria
  • 700,000 million actinomycetes (ray fungi)
  • 400,000 million fungi
  • 50,000 million algae
  • 50,000 million protozoa

Just to put such numbers into perspective, one handful of earth con­tains more organisms than there are human beings on Earth!

Today about 100,000 types of fungus are officially recognized. Each one has a role to play in the process of tilth formation, and each one has specific metabolic products (enzymes). Each species can live for hours, days, or weeks, vanish, and then reappear.

However, it cannot be claimed that a fertile soil requires a particular number or combination of microorganisms. In spite of all technical progress it will never be possible to imitate the natural milieu in the earth, which changes from hour to hour and season to season.

In any case, it is certainly true to say that the living substance within the soil is extremely sensitive and easily changed, and it can be severely damaged by unsuitable methods of cultivation. Damaged organisms, as we will see, pass on their unhealthy imbalance and lead to infertil­ity as well as increase the susceptibility of the plants to diseases, pest infestation, and decay.

The Cycle of the Living Substance

In 1951 Hans Peter Rusch and E. Santo unveiled their Law of the Preservation of the Living Substance in the medical journal Med­izinisches Wochenblatt. According to this theory, nature cannot afford the luxury of allowing the essential elements of life to decompose (or, as chemists would say, to mineralize) after the death of organisms, tissues, and cells. A disintegration following a set pattern, a straight­forward mineralization (decomposition of organic matter into the in­organic components) of living substances, does not exist.

Certainly, the specific living being putrefies; the mortal frame re­verts to that out of which it was made—Mother Earth. Everything necessary for the building up of an organism is discarded; mineral be­comes mineral again, carbohydrates become carbonic acid and water, complicated proteins are split up into very simple components, and everything becomes earth and dust once more. Everything which we commonly consider to be alive obviously has to die and decompose at some point. But life in itself thereby does not come to an end as a result of this; on the contrary, it begins again. Out of the disintegration process something emerges that could be referred to new life from the ruins, namely the fertility of the soil.

Erhard Hennig was an agronomist who devoted himself to agriculture from an early age. He worked extensively as a farmer, agricultural consultant, journalist, author, and lecturer and worked and taught at Humboldt University in Berlin. Hennig died in 1998.