Soils Need Living Fertility

The author, Professor Emeritus, Dept. of Soils, University of Missouri, Columbia, has spent a lifetime studying the influence of soil fertility on the health and well-being of plants and animals out of which has come his conviction that soils need living fertility.

Nutritious grass was nature’s climax crop in this Santa Rita Mountain Valley in 1903 when the cattlemen’s paradise was discovered (upper photo). But after the cattle removed, as beef, what had been going back into soil as organic plant food, mesquite was man’s climax crop in 1943 (lower photo). This was the result of two original bushes (underlined, upper left of upper photo) taking over the area.

 

Since proteins are the only organic compounds that carry life, all life can live only because it either appropriates or synthesizes proteins required as a particular set of amino acids.

Each of those acids, in turn, is synthesized from elements–carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur by only two life forms–plants and microbes.

Microbes and plants are protein-creators because of their closer connection with soil. They are protein synthesizers by means of creative power within the “handful of dust.” That power is fertility of soil.

Science still leaves us far short of complete comprehension of all biological and biochemical facts of nature’s growing of crops and livestock.

Our sciences of agriculture depend much on only inorganic chemistry. We study ash of plants and inorganic elements of soil. By matching those two Quantitatively against each other we learn but little, and that only as one or more of the required nutrient elements are absent from soil, and thereby from plants.

Lack assurance. Even when we use modern concepts of prevailing chemical extraction tests of soil, we do not gain much assurance about soil needs–its treatments required to grow proteins, and those nutrients essential in animal nutrition. Through chemical test, we have only broadened our concepts somewhat by our improved understanding of how fertility of soil must be insoluble but yet available to the microbes and plants during the growing season.

About soil tests for organic matter (nitrogen, carbon, phosphorus, and sulphur, we are still much in the dark. Sulphur, carbon and nitrogen are lost to air on converting plant to ash. Consequently, we fail to believe that organic compounds of soil are taken by plants as nourishment. We have left out of consideration, as an unknown, the soil’s organic part or what seems to be half or more of the creative power of soil.

You might not consider phosphorus an organic part of plant nutrition, yet it is from the rancher’s belief that phosphorus should be mixed and applied with barnyard manure, that research attention is now testing and establishing biochemical wisdom in that theory.

Greenhouse tests. Studies in the greenhouse and soils laboratory, by means of radioactive phosphorus grown into barley and that used as dried green manure for a succeeding crop of soybeans, have shown phosphorus in that organic form 100 times more efficient in feeding itself to the soybean crop than was true for other forms of phosphorus in a soil which was high in that nutrient according to soil tests.

Sulfur, a key element in normal processes of cell division, is also related to organic matter of soil. Up to this date, we do not list sulfur as an inorganic element under fertilizer inspection. That service, emphasizing solubilities in water as its criteria, lists only nitrogen, phosphorus and potassium for certification of fertilizer’s contents.

Protein index. Nitrogen, measured by ignition or ashing in sulfuric acid and taken as the index of protein in crops, represents gross distortion of natural facts, when the claim is made that by fertilizing the soil with nitrogen to feed the soil microbes and crops, one gets higher concentrations of proteins grown into plants on that soil.

It has required some devastating droughts with deaths of animals by high nitrate content in the crop, like corn, to convince many that by measuring total nitrogen in corn plants and multiplying that by 6.25 and calling the result protein, we are not measuring living proteins.

Dangerous. Nitrogen as fertilizers for non-legume crops, like corn, may be a dangerous disturbance to nutrition of animals grazing them, especially, after dry spells. Also for legume crops, nitrogen fertilizers have demonstrated refusal of hay in trials by rabbits offered in different lots to permit their choice.

Test animals ate less hay as there was more nitrogen applied and as crop yield was larger. Such tests confirms the cow’s refusal to eat tall green grass of spots in the pasture occasioned by her urinary or fecal droppings.

The animal does not measure nitrogen and multiply that result by an arithmetic factor and call it protein. The dumb brute applies the simple test of feeding value by eating it or refusing to eat it.

In interpretation of laboratory tests we have assumed too much when we believe that all organic nitrogen is protein, or inorganic elements in the ash are the only form of nutrients taken by plants. But slowly we are suspecting that organic matter is a neglected half of soil as plant nutrition and animal nourishment. Our laboratory concepts may be much farther from the facts of nature than we realize.

Natural climax. Any crop at its best in nature, or what we call a natural climax crop, occurs only after it has grown in the same place continuously and all the successive crops have died there to build up the soil organic matter. Our removal of the annual crop of organic matter in our ranching practices violates the principle of ever arriving at a climax crop in terms of a pure stand, an excellent growth and yield, a self-protection against pests and diseases, and a fecund reproduction in terms of generous seed yields.

Hence, our neglect of maintenance of soil organic matter may be the major, but unrecognized, factor in the poor health and poor nutritional value of the crops as feed and food for animals. We may look to nature and note limitations or various forms of life to soil areas according to fertility.

Balance. Within plants, as in animals and humans, proteins must be in balance with carbohydrates which give only calories in life processes. Carbohydrates within plants serve as “starter” compounds for synthesis of proteins from them provided the balanced fertility of soil serves accordingly.

Plants can convert carbohydrates into proteins, but animals cannot. Strangely enough animals can reverse that process.

Synthesis of proteins by plants seems to be a case in which some of the carbohydrates serve as raw materials out of which proteins are made. This is brought about by combining with those carbohydrates some nitrogen, some phosphorus, and some sulfur, all coming from soil. Some calcium, some magnesium, and several other soil-borne nutrient elements are required in the enzymatic agencies or other helps, while more of the carbohydrates are consumed as energy materials for bringing about this conversion process.

A natural law concerning relation of fertility of soil to plants composition tells us that on soils being developed under the limited climatic forces of moderate rainfalls and temperatures–soils with a wide calcium-potassium ratio–mineral-rich, proteinaceous crops or foods as well as the carbonaceous ones can be grown.

Excessive forces. But on soils under destruction by excessive climatic forces–those with a narrow calcium-potassium ratio–protein production is not so common while the production mainly of carbohydrates is almost universal. In the climatic setting of the former soils, nature grows healthy animals; in that of the latter soils, she fattens the less healthy ones.

Now that soils have been under cultivation for longer times, many kind of crops have been grown on them with varied success, and animals fed the crop from those soils have shown increasing irregularities in health and reproduction; our observations are pointing to correlations among the above factors; soils, crops and livestock.

Among those correlations, we are slowly recognizing causes and effects, with soil fertility as former and disturbed animal health as the latter.

Unfortunately, our past emphasis on growing most any kind of crops–many of them decidedly foreign–has brought about seriously disturbing problems of fertility management now that, with animals more confined, those same but limited soils must be treated to nourish crops that guarantee feed of quality.

The cow’s struggle to survive exhibits itself as a protest against our ways of feeding her when she breaks through the fence.

Discrimination. With such instinctive biochemical discrimination as the cow’s, would it not be biologically wise (and also economically) to use the cow’s selective talents as criteria of our wisdom in managing the soil fertility to produce healthy livestock via nutrition rather than for crop yields of merely more bulk per acre?

Any soil management program must now aim for the production of proteins of the highest nutritional quality. It may be well to consider nature’s laws which in the future will control life as immutably as they have in the past.

There has come much biological degeneration in the health of many life forms, which had been prevented–not cured–in the course of their natural evolution. This seems to constitute a clarion call–loud and clear–for much more natural science and its application to agriculture.