Soil Management by Nature or Man?

In our studies of how Mother Nature was growing crops which were able to protect themselves against pests and disease to survive the ages, and to be available for domestication by man when he took over the soil and crop management, we find that two basic requirements had always been met or fulfilled.

In the first place, rock minerals were weathering in the soil to remind us of the poetic claim that “The Mills of God must grind.” In the second place, the organic matter grown on the soil was naturally put back in place on top or within the soil for its decay there. That served to put microbial life into the soil. It generated the carbonic acid there (and other acids of decay) to break some of the nutrient elements out of the rock more rapidly for them to be caught up and held, or adsorbed, by some of the more stable, weathered, non-nutrient elements like the silicon of the clay. That adsorption holds them for plant services when the plant uses the same kind of carbonic acid to take those nutrients off by trading the hydrogen, or acid, for them.

Nature’s Self Protection

By means of grinding fresh rock regularly as natural mineral fertilizers in the soil, and by conserving the organic matter to go back to maintain the soil’s humus at higher levels, nature had protected her crops so they grew annually from their own seeds. By a unique self protection they were doing well when man came along to take over what we call “scientific” crop management and “scientific” soil management. Certainly we are not now duplicating those practices in which nature was more successful than we appreciate.

When we began the study of how soils feed different plants naturally, we started by chemical analyses of the elements we could separate out of the plant’s ash. We listed the kinds and amounts our analytical ingenuity let us specify. We used the ashing procedure to do the same to the soil. Then we tried to match the elements given for the soil against those specified for the plants.

Among those in the plant, especially wood ashes, the potassium was the highest one. Phosphorus was next in order and calcium, or lime, was the third at the top of the list. There was often some sodium. Then there were many other elements of lesser amounts.

In the ash of the human body and other warm-blooded animals, there appear again calcium, phosphorus, and potassium–the same three elements as in plants. But calcium, not potassium, comes first in the largest amounts. Phosphorus is second and potassium is third, or quite the reverse of the positions in plants. As vegetarians building bodies, we ask our physiology to juggle those elements, eaten in one order of amounts in our food and into another decidedly different order for building our bodies.

Protein Supplements

That chemical composition of warm blooded bodies, demanding high calcium and phosphorus, gives reason for growing and eating legume plants (peas, beans and other pulses), which are protein-rich as well as mineral-rich, to be protein supplements to the nonlegume, low-protein or fattening foods we eat. We use legumes also in animal rations as protein supplements to the pasture grasses for prevention of deficiencies in essential mineral elements and in nitrogen–the element by which we distinguish, chemically, the proteins or living substances.

Legumes can take nitrogen from decaying organic matter in the soil. But when supplied with generous mineral fertility, especially calcium and magnesium as carbonates in limestone and other substances, legumes can use some of the seventy million pounds of the atmospheric nitrogen (over every acre) to build their own protein.

Putting legumes into pasture grass mixtures was nature’s way of growing good grazing for the American bison on the prairies. That provided a more nearly balanced animal ration by the bison’s choice among the sixty to seventy-five species of plants offered by the prairies and plains. Legumes were nature’s synthesizers of protein by using atmospheric–not chemical-salt–nitrogen. They supplemented the nonlegume plants in their nitrogen demands from the soil. They also prepared the combined nitrogen for giving more complete protein supplies in the nutrition of other life forms calling for that food supplement.

We now have commercial chemical salts of nitrogen so widely available to be applied as fertilizer to pasture grasses to make them rich in nitrogen, and “crude” protein, as the chemist measures it. Since nitrogen is the element distinguishing the protein, it is apt to be claimed that “we can now grow more grasses per acre and make them richer in nitrogen and, therefore in protein, to be the equal of legumes. Consequently, we do not need to grow the legumes, which are so hard to grow anyway.”

Specific Compound

But proteins are compounds very specific in more than just nitrogen. Nitrogen in some plant compounds may be poison, as it is in regrowth of sorghums with cyanide nitrogen. That pasture grasses fertilized heavily with nitrogen are not the equal in feed value of grasses growing simultaneously on soils with legumes as companion crops for animals grazing them is told us when the latter in that crop combination serves to make them as feed grow more young animal weight than the former does alone.

Fertilization of pastures by nitrogen only is by no means the equal of grasses limed and phosphated to give plenty of calcium, magnesium, phosphorus, potassium and all else and with legumes grown along with them. The latter crop combination, coupled with the fertile soil, exhibits the higher creative power for the living substance–protein–which demands the higher amounts of ash elements and nitrogen from the air to grow a quality of feed supplement which grasses cannot do even if they can take more nitrogen than usual from the soil.

Consequently, we need legumes to grow their bodies of the separate cells. Those have the “grow” power. Non-legumes make the carbohydrates, the “go” power, and the power for hanging on the fat. But a fattened animal with power to “gain” in weight cannot go very far nor very fast. We need soils high in calcium and other fertility elements to supply “grow” foods. We are still able to grow many “go” foods easily. But only “grow” foods build bodies, protect them against diseases and pests and enable life forms to reproduce the species to populate the earth.

For growing legumes and better non-legume crops which are mineral-rich and protein-rich, the soils must be well-stocked with calcium, magnesium and potassium, usually accompanied by sodium, some hydrogen or acid, all as positively charged elements in their electrical behaviors. There must also be present some of the trace elements in that same classification of the positive. In order to be available to the plant roots, they must all have been broken out of the rock reserves and adsorbed, or held, on the clay surface against loss in percolating soil water. Yet they must be exchangeable to the plant root, trading hydrogen or acidity for them.

Soil’s Holding Capacity

According to our knowledge to date, the soil’s total capacity to hold electrically positive nutrients in available form should have about 60-75% for calcium, six-12% for magnesium, three to five per cent for potassium, and not more than that much of sodium and also all the needed trace elements and non-nutrient hydrogen, or acidity.

Those figures represent the soil’s content of positively charged elements in what, to date, we may consider a balanced plant ration of that portion of the list of required elements for growing legumes. Simultaneously, more nutritious grasses are grown, to make for better grazing–a point well proven when animals have a choice. It may not be so complete as nutritious feed in baled hay or in mechanically pelleted feeds.

In our preceding remarks, we have not spoken about the soil’s organic supplies of nitrogen, sulfur and phosphorus in the required plant’s ration. We have not mentioned some of the trace elements also connected more actively with the supply of organic matter than with the reserve minerals.

We need to look to the organic matter of the soil to make these last three more essential major nutrient elements available to the crops. We need to remind ourselves that it is the organic matter that makes the surface layer the “living soil” and the “handful of dust” with its power for creating life.

We must not forget that microbes are what make a living soil “alive.” And far more important, we must remember that soil microbes, like all other microbes, eat at the first sitting or first table. Plants eat at the second. Microbes go first for energy food, since they cannot use the sunshine’s energy directly. Plants go first for “grow” food, since they can use sunshine energy that way.

A sprouting seed “roots” for a living, or for “grow” food first. It puts up its advertising of growth by showing its leaves above the soil in the sunshine second.

Microbes are the decomposers of the organic matter and the conservers of the inorganic fertility, of the nitrogen, of the sulphur and of the phosphorus. Those three elements do not escape so much from a soil which has plenty of organic matter and growing crops to conserve those elements. We need to consider organic matter to conserve, to mobilize and to increase the nitrogen, the sulfur and the phosphorus of the soils, if those are to be fully productive.

Soil microbes oxidize carbon, nitrogen, sulfur and phosphorus to get energy thereby. It is in their oxidized forms that those elements are taken into the plant. Carbon is taken into the leaves. The others are taken into the plant root and, thus, all are in cycles of re-use.

Symbiotic Activity

It was by that more complete recycling for conservation that nature built up the soils in organic matter which we are compelling our microbes to burn out so rapidly when we return primarily chemical salts and little carbon of organic matter by which in this combination for microbial service, these fertility elements must be held in the soil. Plants and microbes must be in symbiotic activity and not in competition for fertility if our productive soils are to be maintained.

Carbon, nitrogen, sulphur and phosphorus are the negatively charged elements with which the positively charged hydrogen, calcium, magnesium, potassium and sodium combine to make the readily soluble inorganic salts. But in those combined forms they are not held by the soil as such. They are ionically injurious to plant roots. They are leached out by percolating rainwater. It is the clay humus part of the soil which filters the positively charged ions, or elements, out of those salts, much like the household water softener takes the calcium, or lime, hardness out of the water supply. The clay-humus holds them as insoluble, yet available, to plant roots which are trading acid, or hydrogen, for them.

The negatively charged, soluble nitrates, sulfates, phosphates, so oxidized by the microbes, serve as nutrition for them and for the plants to be reduced into the organo-molecular states of living tissue where they are insoluble but functional in large organic molecules and not as salts. On death, they are oxidized again for microbial energy and repeat the cycle.

It is in this natural plan of soil management where we must recognize the real service by the fertility elements of soil, air and water playing their roles in creation before we can take over for wiser management of nature’s part in crop production. Her two phases of management stand out. (1) Nature returned the organic matter as completely as possible, in that she held many of the fertility elements and kept them available. (2) She grew crops where she also added unweathered mineral salts and dusts through winds with their storms of such and by overflowing waters with their inwash of deposited minerals.

By that simple, two-phase procedure of fertility management, nature had many different crops of healthy plants here for man when he arrived. But each crop was on its own particularly suitable soil in its specific climatic, geo-chemical and balanced fertility setting with man and warmblooded animals on the high-calcium soils. We have not yet included calcium as the foremost fertility element when we list the contents of commercial fertilizers, for the inspector, even though we lime the soil to combat its acidity and, thereby, work against the very mechanism by which the plant roots feed our crops.

With a threatening population explosion, and the threat of pollution of our entire environment in our war on pests and diseases, to say nothing of the wide use of hydrocarbon fuels, will we eventually repent as prodigals in spending our creative substances of the soil, and return to nature which we must finally admit is still the greatest creator the earth has known in her quiet patience and transcending wisdom? Let us hope that we return from our prodigality of the soil before it is too late.