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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, written by Erhard Hennig. Copyright 2015, softcover, 198 pages. $24.00 regularly priced. SALE PRICE: $19.20.

Humus forms as a result of the complicated interplay of inorganic conversions and the life processes of the microbes and tiny creatures living in the soil. Earthworms play a particularly important role in this process. Humus formation is carried out in two steps. First, the organic substance and the soil minerals disintegrate. Next, totally new combinations of these breakdown products develop, which leads to the initial stages of humus. Humus formation is a biological process. Only 4–12 inches (10–30 centimeters) of humus-containing soil are available in the upper earth crust. This thin earth layer is all that exists to provide nutrition to all human life. The destiny of mankind depends on these 12 inches!

Secrets of Fertile Soil

Cultivated soils with 2 percent humus content are today considered high-quality farm land. What makes up the remaining 98 percent? Depending on the soil type, soil organisms constitute about 8 percent, the remains of plants and animals about 5 percent, and air and water around 15 percent.

The remaining 70 percent of soil mass is thus of purely mineral origin. The mineral part of the soil results from decomposition and the erosion of rock. The dissolution of these components is carried out by the lithobionts, which can be seen as the mediators between stone and life. It was, once again, Francé who coined the term “lithobiont,” which means “those who live on stone.” The lithobionts are the group of microbes that begin the formation of humus. They produce a life-giving substance from the nonliving mineral. On the basis of this process, living matter, earth, plants, animals, and human beings can begin, step by step, to build.

Only soils with an optimal structural state of tilth have a humus content of 8–10 percent. Untouched soils in primeval forests can, at best, reach 20 percent. A tropical jungle can’t use up all its organic waste, so humus can be stored. All forests accumulate humus, but real humus stores only emerge over the course of millenniums. Once upon a time accumulations of humus known as chernozem (Russian for black earth) could be found in the Ukraine.

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Book of the Week: The Secret Life of Compost, by Malcolm Beck

By Malcolm Beck

Editor’s Note: This is an excerpt from Acres U.S.A. original book, The Secret Life of Compost, written by Malcolm Beck. Copyright 1997, softcover, 170 pages. $19.00 regularly priced.

There are many beneficial forms of life in the soil. Scientists now tell us there is more tonnage of life and numbers of species in the soil than growing above. All of this life gets its energy from the sun. But only the green leaf plants have the ability to collect the sun’s energy. All other life forms depend on the plant to pass energy to them. The plants above and soil life below depend on each other for their healthy existence and continued survival.

The Secret Life of Compost

The Secret Life of Compost, by Malcolm Beck

Another beneficial microbe that colonizes plant roots was introduced to me by Mr. Bill Kowalski of Natural Industries. He said he had a microbe that has been shown to knock out a half dozen root rots in the laboratory. At first I told him I was not interested unless it was known to stop cotton root rot, because the only deterrent to a booming apple industry in the hill country of Texas is cotton root rot. He replied it hadn’t been tested on cotton root rot, but he would be glad to give me some if I wanted to try it.

Okra is related to cotton and back when we were farming we planted lots of okra. We had a spot on the farm where the plants suffered from cotton root rot. To test the new microbe, we planted two rows of okra across the root rot spot, then skipped two rows and planted two more rows of okra. The seed in these last two rows had been soaked in the product for a few minutes to ensure they would be inoculated with the microbe.

After the okra was in full production, Bill came over and we went out to inspect. Immediately we noticed the inoculated okra averaged a full 12 inches taller than the control rows. We walked down the control rows first and pulled up the smaller and weaker looking plants. We found the roots to be badly infected with some form of root rot and also full of root knot nematodes. Inspection of the inoculated row found not a single case of root rot or nematodes. Continue Reading →

Bt: Toxic Soil & Nature’s Balance

Bacillus thuringiensis (Bt), a GMO more commonly known as Bt toxin, is spliced into the seeds of crops as a biological pesticide. Our environment is now sustaining genetically modified organisms in the soil, affecting everything we grow. As the seed sprouts, the Bt comes alive and grows with the plant as well as in the surrounding soils. This is a biological, living GMO pesticide that remains in the soil long after the plant is harvested. It also remains in every cell of the plant — all the way from the field to the end product, be it food, clothing, paper or tobacco.

Aerial of intersecting roads in rural Indiana.

GMOs are interrupting genetic expression of any and all plants grown in soil that has nurtured compromised seeds. This includes organic farming products coming from any farm that has been transitioned from conventional farming. To-date, there are 33 common crops being grown and harvested on over 444 million acres of land worldwide.

Beyond the soil, the effects of Bt toxin are found in the genetic makeup of pollinators, as the toxin has been found in nectar and pollen of the plants. These are taken back to the hive where it accumulates and contaminates the hive, ultimately contributing to colony collapse disorder.

We find these toxins in animals and in people (it has been found in breast milk and body tissue). It is now being reproduced in the gut. Bts are airborne, traveling in pollen and dust, spreading worldwide. DNA transfers naturally through mechanisms that allow gene flow across species. In this way Bts in the soil as well as in the air serve to compromise all efforts to produce organic and non-GMO plants, challenging their genetic integrity above and below the soil. Continue Reading →

Soil Organic Matter: Tips for Responsible Nitrogen Management

For soil organic matter to work the way it should, it depends on a careful balance of nutrients and minerals, including one of

Healthy, homegrown carrots in rich soil.

the most important elements — nitrogen. One of the great paradoxes of farming is that lack of nitrogen is regarded as one of the great limitations on plant growth, and yet plants are bathed in it because the atmosphere is 78 percent nitrogen.

Most plants cannot use nitrogen in this form (N2) as it is regarded as inert. It has to be converted into other forms — nitrate, ammonia, ammonium and amino acids for plants to utilize it.

In conventional agriculture most of these plant-available forms of nitrogen are obtained through synthetic nitrogen fertilizers that have been produced by the Haber-Bosch process.

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Humic Acid: The Science of Humus and How it Benefits Soil

Humic acid is a group of molecules that bind to, and help plant roots receive, water and nutrients. High humic acid levels can dramatically increase yields. Humic acid deficiency can prevent farmers and gardeners from growing crops with optimum nutrition. Conventional wisdom today ignores humic acids, though, holding that it is impossible to grow and maintain an urban landscape such as a park, golf course, or lawn without high-analysis NPK fertilizers.

This article will drill down into the details on humus. We can adjust our soil biology and chemistry and achieve better yields if we understand its characteristics.

Humus vs. Organic Matter

We must begin by understanding that there is a difference between soil organic matter and humus. “Humus” is a general term that describes a group of separate but distinct humic substances. “Soil organic matter” is material that is decomposing at various rates in the ground.

Some of the most common substances we collectively refer to as “humus” include:

  • Fulvic acid: a yellow to yellow-brown humic substance that is soluble in water under all pH conditions and is of low molecular weight.
  • Humic acid: a dark-brown humic substance that is soluble in water only at higher soil pH values and is of greater molecular weight than fulvic acid. Humic acid may remain for centuries in undisturbed soil.
  • Humin: a black humic substance that is not soluble in water at any pH, has a high molecular weight, and is never found in base-extracted liquid humic acid products.
Humic acid

Adding a small amount of humus to an acre of soil can achieve positive results.

Applying organic matter is certainly an excellent way to remineralize a soil that has been leached or has no chemical reactions, such as with some sands. Sand with a low cation exchange capacity (CEC) has difficulty holding onto the cations of nutrients, and these cations can easily leach deep into the soil and become unavailable for plant uptake.

Sandy soils are also unable to hold onto water when arid conditions prevail and humus is lacking. Sands reside in a condition of “feast or famine,” since water and nutrients are only available for a short time after they are applied. Biomolecules of humus can help retain water and the ionized nutrients that are produced by the natural cycling of organic biomass, compost, or other sources of fertilizer.

The electronegativity factor of humic acids is key in developing and maintaining a healthy and sustainable soil. The source of these humic acids in a sustainable agricultural program, organic certified farm, or urban landscape can be decaying organic matter such as compost. In essence, this is fertilizer in an organic form. It is therefore important to know the ingredient source and the nutrient analysis of your compost.

Humus is powerful stuff, and a tiny amount can produce a huge measurable result. We have seen as little as 40 total pounds on an acre of farmland increase the yield of a crop dramatically.

The Physics of Humic Acid

Humic acids are extremely important as a medium for transporting nutrients from the soil to the plant because they can hold onto ionized nutrients, preventing them from leaching away. Humic acids are also attracted to the depletion zone of the plant root. When they arrive at the roots, they bring along water and nutrients the plant needs.

Humic acid and grass root system

Humic acid brings nutrients directly to plant roots.

The depletion zone is the area close to the root of a plant from which the root draws (depletes) nutrients. This zone can become particularly depleted if there is a lack of either humic acid or mycorrhizal fungus. When plants are mycorrhizal, the depletion zone is of less importance. Mycorrhizae have hyphae micro-tubes that can extend much further into the soil than the host plant can reach. They can gather mineral nutrition for the benefit of the host plant from outside the depletion zone. Humus is even more critical for plant nutrient availability and uptake if there aren’t healthy mycorrhizal relationships in the soil.

Positive ions are more easily absorbed by a plant’s root because the root has a negative charge. In other words, the positive (cation) is attracted to negative (the living root). Humic acids hold cations (positive ions) in a way they can be more easily absorbed by a plant’s root, improving micronutrient transfer to the plant’s circulation system. This works because humic acids (ulmic, humic, and fulvic) pick up positive ions and are then attracted to the root depletion zone and to the hyphae micro-tubes of mycorrhizae.

Since the root’s negative charge is greater than humic acid biomolecules’ negative charge, scientists theorize that the micronutrients are taken up by the plant’s root and are absorbed by the plant’s circulation system. Some of the micronutrients are released from the humic acid molecule as they enter the root membrane, but we are now realizing that the plant will also uptake some of the lighter molecular-weight humic acids as well. In essence, the humic substances are chelating such cations as magnesium (Mg2+), calcium (Ca2+), and iron (Fe2+). Through chelation, humic substances increase the availability of these cations to plants.

How to Build Humic Acid Levels

Compost and other sources of decomposing organic matter are not an efficient way to build soil humus levels. Compost rapidly decomposes and leaves its minerals behind, releasing carbon into the atmosphere as CO2. Humic substances, on the other hand, are stable, long-lasting biomolecules. Components of humus have a mean residence time (based on radiocarbon dating, using extracts from non-disturbed soils) of 1,140 to 1,235 years, depending on the molecular weight of the humic acid.

If you really want to fix or rehabilitate a soil, increase its CEC, improve its tilth and porosity, improve water availability for conservation, and therefore make a soil a healthier terrestrial biosphere for all plants, roots, microorganisms, you must depend on humus. Humus is a product of soil chemistry, and is dependent upon a source of its precursor chemicals: amino acids.

Amino acids are the building blocks of protein. The best source of the amino acids in a natural ecotone are produced by the Glomus species of mycorrhizae. These are associated with any grass in a natural, undisturbed site. The tallgrass prairies of the Midwest exemplify this soil-building process better than any ecotone on earth, because grasses utilize a Glomus-mycorrhizal relationship. This is why there is was so much humus-rich topsoil in the Tall Grass Prairies. Glomus makes a soil protein called glomalin, a substance that is rich in amino acids. Combined with humus, they create a huge carbon sequestering and banking factor.

Scientists can measure the percentage of calories in compost that come from proteins (the amino acids), carbohydrates, and fats. This enables them to measure the lack of humus-making potential of compost. Even in supreme-quality compost, the percentage of calories coming from amino acids (protein) is less than 5 percent. Since it is difficult to rely on the perfect amino acid ratio in compost because of differing manufacturing quality controls and ingredient consistency, we cannot predict a 100 percent efficient conversion of all these amino acids into humic substances. Compost or other soil amendments of organic matter are therefore not a reliable way of increasing soil humic substances.

Attempting to add adequate amounts of humic acid through application of compost would require such a huge amount that it could lead to overdosing the site with nutrients. In fact, the better the quality of the compost, the more concentrated the nutrients will be, and the less you should use. In the case of our TTP Supreme Compost, for example, we recommend using it sparingly – never more than 60 pounds per 1,000 square feet or 2,600 pounds per acre. And this is assuming no other fertilizer is being used at the same time.

Humus supplementation is necessary if you want humus. You can measure the quantity of humic acid in a compost product at a qualified lab. A good quality compost will measure around 5 to 8 percent humic acids.

Benefits of High Humic Acid Levels

One obvious benefit of humus we have seen at our Arboretum in Los Lunas, New Mexico, has been the aggregation of clay. This aggregation has made the clay more porous, soft, and aerobic, with better drainage, resulting in deeper root growth of all plants. The site was purchased in 1986 with clay soil 12 feet deep and a pH ranging from 8.3 to 9.2 – so alkaline that in the winter the site would turn white.

Today we have one of the largest oak species collections of the Quercus genus in the United States, and the largest collection of native oaks of the Chihuahuan Desert Region in North America. Also on the site are several types of redwoods, maples, dogwoods and giant timber bamboo. None of these plants should be able to grow on soils with the conditions we started with, but with the power (or magic) of humic acids we have rehabilitated the soils to a productive and healthy level.

Finally, “Humic Acids: Marvelous Products of Soil Chemistry” (The Journal of Chemical Education, December 2001) states, “Humic acids are remarkable brown to black products of soil chemistry that are essential for healthy and productive soils. They are functionalized molecules that can act as photosensitizers, retain water, bind to clays, act as plant growth stimulants, and scavenge toxic pollutants. No synthetic material can match humic acid’s physical and chemical versatility.”

By Michael Martin Meléndrez. This story was first published in the August 2009 issue of Acres U.S.A. magazine.

Sustainable Soil: Four Rules for Controlling Organic Inputs

Sustainable soil requires profitability.

A girl plays in the soil.

No matter how desirable a sustainable program might be, it must be tempered by the realities of making a total commercial agriculture program work economically. Growers attempting to deal with this reality often focus on sustainability in a piecemeal manner, as they do not always understand the basic rules or guidelines that are required of a sustainable soil program. In this article, we will review the guidelines on achieving sustainability and also report on new developments in sustainable soil nutrition products.

Commercial agriculture programs are often unable to profitably approach sustainability due to economic pressures. Time-honored practices that require land to lay fallow and the use of cover crops along with manure or compost applications are expensive when compared to the rapid prepare-fertilize-plant harvest cycle that has come to dominate commercial practice. Sustainability struggles within such a marketplace, as growers rarely receive a premium for crops grown on sustainable soil versus crops grown conventionally. When a grower is faced with the hard choice of feeding his soil or feeding his family, the family will win.

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