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Soil Fertility as a Pattern of Possible Deficiencies
Published in Journal of The American Academy of Applied Nutrition, Spring 1947, pp. 7-26.
* * *
It is the purpose of this paper to lead your thinking to the earthy subject of soils, particularly as a pattern of possible diet deficiencies in animals including man.
It is my good fortune to address you just after you have made a wise application of your knowledge of nutrition. This is my first experience with a group so intent on nutritive contents that the very menus carry not only the listing of foods but their caloric, vitamin and quantitative analysis. I was glad that the arithmetic proved my dinner was as good as it tasted to me.
It is my purpose to lead your thinking, as medical men, as dentists, and as nutritionists, a little further back toward the origin of foods than the butcher’s block, the corner grocery or the dairy. There, foods are dispensed, but foods are built upon the farm and it is toward the farm we must look to understand and evaluate them.
In the store foods are known by the labels upon them. A head of lettuce is a head of lettuce although one head may have been grown in the soil of a western state, its neighbor in the tired soil of an eastern farm. Butter is butter regardless of the fodder upon which the source cows were fed. Ground beef is hamburger though one batch of endemic protoplasm cooks down to nothing as the water boils out, another seems all meat.
On the farm where vegetables are grown and live stock is fed upon them, the relative quality of foods is built into them by the purely local soil chemistry and weather. To paraphrase, by the soil upon which they grew ye shall know them.
Agriculture, which was originally the industry of growing foodstuffs, and became the business of exploiting virgin soils, now is being forced to learn how to build foods by conserving and reconstructing worn-out soils. The richness of our soils is one of our greatest national resources. For years we have exploited it without thought (or consideration) of the eventual depletion of that wealth.
You, who are interested in applied nutrition, are particularly concerned over the qualitative feeding of our people. It should not be on the basis of stuffing the stomach while starving the body, but rather on an optimum level that will support our bodies, endow our offspring with inherent health and bring the vigor and nervous stability to our mental processes that will enable us to fulfill the responsibilities of world leadership now thrust upon us.
Clay is the dynamic part of the soil.
How is it that the soil, which is supposedly inert, insoluble, and just “dirt” to many people, can provide the essentials that go to make food? The answer lies in understanding the relations by which the soil, as a mass of decaying organic matter and decomposing rock, can contribute what it takes to make vegetable or animal or human tissues.
Many people have the concept that the nutrients in the soil are soluble and that the plant puts its roots into the soil and sucks out nutrients along with the water. We’ve been in error to believe that might be the way it works. We find that the nutrients in the soil are held by adsorption forces on the clay. While the rock is breaking down, the dilute solutions of it are filtering through the soil to have the essential, positively charged (and many of the negatively charged) nutrients caught up by the clay. When we speak of the soil as sand, silt and clay, we need to visualize that the sand portions, if they are not too tremendously insoluble, are breaking down; that the silt portions are breaking down; and that the clay is the residue which of itself has little or nothing to give by its own breakdown. However, it has the adsorptive force which collects and holds the nutrients in high concentrations so that the root can come in and quickly get its supply. But for each supply that is seasonally delivered by the clay to the plants, there must be time allowed to restock that clay. We might think of soil exhaustion, then, as a case in which the clay has quickly given up what it got and then has not had time to restock itself. We must develop an understanding of the mechanism by which this soil functions as a reservoir of nutrients for the crop, and thereby an understanding of why we might expect some deficiencies in nutrition.
Composition of human body, of plants, and of soil suggests deficiencies.
Let us look at the chemical composition of the human body, in contrast to the composition of plants. Particular attention is drawn to the fact that, whether plant or animal or human body is considered, air and water constitute about 95% or 96% of each. In other words, with the carbon and the oxygen coming from the carbon dioxide of the air, the oxygen and the hydrogen coming from water, plus a small amount of nitrogen that in the ultimate comes from the air also (though most plants take it from the soil)–those constituents of atmospheric origin make up the bulk of the plant body and the animal body. They represent the loss by combustion. They are distilled off readily at high temperature. The remaining content of the body, namely, 5% comes from the soil as the ash.
However, that small amount from the soil is significant. The atmospheric contribution may well be taken as the warm, moist, breath of creation, which is blown into the handful of dust. The 5%, though, which is that handful of dust, determines how successful that blowing operation will be in giving something that is more than hot air in the final result. We may well give thought to the problem of eating our nutrients from the atmosphere. The plant contains about 6% hydrogen, the figure for that in the human body is 10%. In the plant we have about as much carbon as we have oxygen, but in the human body there is less carbon and much oxygen which represents considerable oxidation But there is also considerable reduction when the 6% of hydrogen is increased to 10%. This is illustrated by the conversion of the carbohydrate into fat, since fat-making represents the removal of the oxygen from the carbohydrate compound and the substitution of hydrogen in it. This makes more nearly a straight carbon-hydrogen chain of high heat value on combustion. Conversion of plants into animals increases the hydrogen from 6% to 10%. An increase of about two-thirds. In case of the nitrogen, the absolute increase is from 1.6 to 2.4%, is a relative increase of 50%. You and I in building our bodies by eating vegetable matter must struggle to build up those higher concentrations of hydrogen and nitrogen.
Table 1. Chemical Analysis of the Human Body in Comparison with that of Plants and of Soils
Origin of Source | Essential Elements | Human Body % | Vegetation % Dry Matter | Soil % Dry Matter |
Air and Water | Oxygen
Carbon Hydrogen Nitrogen |
66.0
17.5 10.2* 2.4* ——— 96.1% |
42.9
44.3 6.1* 1.62* ——— 94.92% |
47.3
.19 .22* — |
Soil | Calcium
Phosphorus Potassium Sodium Chlorine Sulfur Magnesium Iron |
1.6*
.9* .4† .3 .3 .2 .05 .004 |
.62*
.56* 1.68† .43 .22 .37 .38 .04 |
0.3= 3.47 *
0.0075 .12 * 0.03 2.46† — .06 .12 2.24 4.50 |
Iodine
Fluorene Silicon Manganese |
Trace | Trace
Trace 0-3.00 Trace |
.1027.74
.08 |
|
Body
Compounds |
Water
Protein Carbohydrates Fats Salts Other |
65
15 — 14 5 1 |
—
10 82 3 5 |
* These are involved in the plant and animal struggles to find enough to meet the high concentrations needed.
= Amounts common as the more available forms in the soil in contrast to the total, most of which is but slowly available.
† This represents struggles by the animals to eliminate it.
Suppose we look at the problem in terms of the nutrients coming from the soil in contrast to those coming from the atmosphere. Calcium is at the head of the list of soil-borne nutrients needed for the human body. At the head of the list for the plant is potassium. These are significant facts. For all the plant operations that produce protein, we must have a high calcium supply in the soils. For those plants, that are carbohydrate makers, we must have a generous supply of potassium. In the plant composition, then, potassium stands highest in mineral elements needed because the plant’s main physiological activity is carbohydrate production. In the human, the main physiological activity is one of protein elaboration while carbohydrates are burning or undergoing decomposition to synthesize it. We need to drive that fact home. One can take a plant and by shifting the relations between calcium and potassium amounts given it, shift it from a plant that is mainly a carbohydrate producer and storer to one which is highly proteinaceous in its synthetic and storage activities.
The human and the animal bodies contain as much as 1.6% of calcium. In our nutrition we go back to the plant that has only .6%, and plants, in turn, go back to the soil that has only .3% of readily exchangeable calcium. Do you see the problem of trying to start with a source of only .3% of calcium; then to increase it in the plant to .6%; and in bringing it from the plant to the human body concentrate it to 1.6%? That represents a problem of increasing the concentration of these nutrients from the soil, not by 50% or 60% as is the case of other elements coming from air and water. It is a problem of increasing by 200% from soil to plants, of roughly 300% from the plant to the human. Finally, in going from the soil to the human, it is a problem of an almost 500% increase. Can you see that the deficiencies in the soil in terms of a simple element like calcium are going to register when they are so highly magnified in this creative process? Nutrition is concerned not merely with the problem of the calcium as a nutrient coming from the plants to the human, but a problem also of its coming from the soil to the plant and thereby from the soil to the human.
When we think of phosphorus we are reminded that it is the companion of calcium for bone construction. Bone is not just a portion of the reinforcement in a flabby body. It is a portion of the essential, physiologically active parts, particularly when we recall that the activity of the bone marrow is one of blood corpuscle regeneration. There is a distinct problem in the provision of phosphorus when there is only seven-thousandths of a per cent of it readily soluble in the soil. The plant must bring the phosphorus concentration from this dilute source up to about .56% within itself, and then you and I must literally double that to make our bodies. From such facts you begin to see that in agriculture we have been putting phosphate and lime on the soil with nutritional benefits to the plant, to the animals and to the humans. But up to this moment we have been putting them on largely in order to make more tonnage, and not because we’ve thought them essential to the animal or human nutrition.
In the art of agriculture lime and phosphate were put on the soil in order to make more food. More recently, seemingly under the science of agriculture, we put them on in order to make more money. Prompted by concern about better nutrition we are beginning to go back to the art and put them on to make more and better food, because those two essential mineral nutrient elements, calcium and phosphorus, play a tremendous role in the elaboration of proteins. They play a tremendous role in the plant’s reproduction by seed and likewise in the human and in the animal reproductive processes.
Figure 1. Wild animals know their medicines. In the forests of the North on the well-weathered soils the calcium and phosphorus dropped as antlers are quickly taken by porcupines, pregnant squirrels and other rodents. (By courtesy University of Minnesota Press.)
With reference to potassium, the struggle for the plant is a difficult one, it is not, however, such a difficult one for the human. The plant finds .03% potassium in the soil, which small concentration must be elaborated to one as high as 1.68%. And then you and I, as humans, like the other higher animals, excrete the excess potassium given us by vegetation. So as long as we had farm animals, particularly horses, which were consumers of large amounts of vegetation as roughages, the animal was putting much potassium back into the soil. This kept it in rotation. But when the tractor came along to replace the horse it made no contribution to that fertility cycle.
Calcium, phosphorus and potassium are at the head of the list of about a dozen of the nutrient elements that come from the soil. If the soil must provide a dozen; if most of our individual rocks contain at the maximum only three or four; and if the particular soil is developed from one single type of rock, it is logical to expect some deficiencies. If a dozen elements are needed, while that rock contains only four, and that rock is converted into soil, the conversion has not added anything beyond those four. And yet we are prone to assume that every soil contains all of the dozen. Thus in terms of its origin, we ought to expect deficiencies in the soil, particularly when our use of the soil is a mining instead of a managing operation. We must expect deficiencies unless we feed the soil to give us output just the same as we feed an animal for a particular output.
Soil mechanisms in plant nutrition.
In considering the nutrition of plants, it has long been the general idea that plants use the nutrients in solution. That concept ought to seem logical to those who put ammonia into irrigation water as a nutrient. However, if we use calcium as a nutrient in solution and increase the amounts in that form applied per plant to be grown, there is an increase in the crop grown up to a certain limit, and then from stronger solutions the crop growth decreases. These higher concentrations literally “salt out” the plant. However, if one gives the plant its calcium in the form of the calcium mineral, anorthite, in this same test series of increasing amounts of calcium by increasing the amount of mineral, one doesn’t improve the crop growth. This is so because the mineral isn’t breaking down rapidly enough for the plants to be nourished. The crop fails to live even though the mineral contains more calcium by several times than was used in solution. But if one will take the solution of calcium, trickle it through some clay, which may be even an artificial one like that used in water softeners, namely permutite, that permutite will take the calcium out of solution and adsorb it. Regardless of how concentrated, or how much calcium we provide on that permutite, there is no injury to the crop. The calcium is held on the permutite in an insoluble but exchangeable form. When the root comes along it trades or exchanges its acidity for this calcium.
Thus you can see the principle of plant nutrition by the soil in which the clay is an adsorber and an exchanger. Thus, if in regions of low rainfall Nature has not weathered the rock down to anything finer than sand, there is need to put something in with the sand to serve as the permutite does. Fortunately, decaying organic matter becomes colloidal in form like the permutite and may serve in that respect. But it is important to note that unless a significant concentration of the nutrient like calcium is put on the clay, the plant gets none of it. This is true because the clay holds it with a force in equilibrium against the plant’s forces. Such colloidal activity is always significant in soils where the rock has not been weathered down far enough to make much clay as is true in low rain-fall regions. And so when one thinks about this whole matter of plant nutrition it must be approached in terms of these fundamental understandings of how, or by what mechanisms, it is that the root and the soil, or rather its clay portion, can get together and the plant to be nourished thereby.
As an illustration of the clay-plant root interactions, increasing amounts of an electrodialized acid clay were put into sand. The sand had nothing of nutrients on it. It had no exchange power. In such large particle size it had no great surface area. But when that clay was added in the increasing amounts the crop grew better accordingly. Putting it another way, they were diseased plants when they were starving, they were healthy plants when they were well fed. They were well fed by nothing other than an acid clay, but by having more of it for more root contact. As there is more clay developed in the soil through greater rainfall thus making that soil heavier, there is the possibility of greater crop production. Thus it is that the farmer in the Missouri river bottom, with its heavy soil, knows that if he can get his corn crop planted after the June flood, he still gets a crop because the soil has a large clay content to give a large amount of nutrients to the crop in a very short time.
Figure 2. “To Be Well Fed Is To Be Healthy.”–More clay in the sand (left to right), even if that clay is very acid, gives better and healthier plant growth. Soil acidity represents deficiencies in plant nutrition.
Plants trade acidity in soil for their nourishment.
If you will consider the plant root as having itself surrounded with carbonic acid (carbon dioxide in water makes carbonic acid), that acid is the ionized or active hydrogen. Hydrogen is the most active of all of our soil elements. It is traded to the adsorption atmosphere of the clay and there it replaces some of the nutrients, which may be well illustrated by calcium. By such trading or exchanging the clay is becoming acid while it is helping the plant to be nourished or the plant to grow. It is by this bartering that growing plants make the clay become sour or acid. And yet we worry about the soil having become acid. Instead of worrying about the acid having come on to that clay, we should worry about the fertility having gone off the clay. And when we talk about soil acidity being dangerous per se, we ought to remind ourselves that this soil trouble might not be due so much to the advent of the hydrogen, but rather to the exit of the nutrients.
If the soil were made up of only clay, then if a crop were grown on it, it would remain sour or acid as we have demonstrated experimentally many times. But if one will mix some original crushed rock, limestone, for instance, granite, or any of the other rocks and minerals, that can be broken down, then the acidity given by the plant to the clay will be transferred to those rocks and minerals. They will be weathered like they are by any weathering agents in the outdoors. The contents of those rocks as nutrients will be moving in the opposite direction to that of the acidity and will serve to feed the plants. It is thus that crops are making the soil acid while they are being nourished.
We have thus come to see that the plant is putting acidity, (active hydrogen) which is not a nutrient, into the soil. Acidity is weathering the minerals, and their breakdown is nourishing the plants and by that means nourishing all of us. Now if the soils don’t have enough clay, we can substitute humus, or soil organic matter, because the dead carbonaceous material of previous plant generations is decaying into the colloidal form, and it serves as an exchange agency in exactly the same way as the clay does. But humus also decomposes faster than clay. Its decomposition is producing ash in that same manner as the decomposition of rock is passing its nutrients to the colloidal exchanger and then to the plant roots When you think therefore of the more sandy, open-textured soils of Los Angeles County, that once had the highest agricultural output of any county in the United States, followed by Lancaster County, Pennsylvania, and then by McLean County, Illinois, is its lowered output today the result of exhaustion of the mineral reserves in the sand? Have not these changes in productivity occurred more probably because tillage operations have been burning this humus out of the soil, and nutrient deliveries have been getting down to a limited mineral level, the weathering being too slow under limited rainfall to keep these assembly lines of food production going at the rate at which we like to have them go? It was this breakdown of the humus of the virgin soil that gave the speed to earlier production.
Diagram 1. The Mechanism of Plant Feeding–Plant nutrients, like calcium, on the colloidal clay or humus are exchanged to the plant root for the hydrogen or acidity it offers. As the colloid takes on more acidity this goes to break down the minerals and restock the colloid. Acidity goes from the roots to the minerals, nutrients go from mineral to the roots, all through the colloid.
It has been the breakdown of the large supply of organic matter in the virgin soils of the United States that gave us our American prosperity–and we might well consider saying “past” American prosperity, because we have gone to the limit of our westward movement to better soils. During our increasing prosperity we were moving to soils that had more organic matter. We were exploiting a great natural resource. We have now reached the limit in gaining by moving. The problem of organic matter, to which we have been pointing with such emphasis, is illustrated not only in your own county, but it is a universal problem. The importance is not lessened because it isn’t quite so acute in some of the other regions where the output of agricultural production is not so nearly complete as food for direct human consumption. Unless we understand these basic principles, by which the nutrients we need from the soil are brought to us through plant help, we are not going to be able to manage this business of food production without suffering deficiencies and the so-called “diseases” provoked by them.
Figure 3. The pattern of annual rainfall gives a pattern for different soils and possible deficiencies in the nourishment of plants, animals, and man.
Pattern of climate suggests pattern of deficiencies.
Perhaps you have not even thought that it is the forces of climate that make the soil, and that the soil in turn feeds us. California has been telling us about its excellent climate for years. But the climatic pattern is an outline of influences, not in terms of how wet we are, or how dry we are, or how warm we are, or how cold we are, but rather the climatic picture exercises its importance because it determines how well fed we are. Perhaps at first thought you will not agree with that statement. Nevertheless, it is a great truth. This pattern gives order to the whole business of nutrition. It exercises its significance not only in the United States, but has its international implications as well. If we take a look at the rainfall of the United States we see in the rainfall the main part of the pattern. Suppose we disregard the western coast, which has so many variations that one can not delineate it on the map and make it clear and readily recognized, and start with western United States with its rainfall of less than 10 inches annually. As we go eastward there is the next area with 10 to 20 inches, and then a long area running north and south with rainfall of 20 to 30 inches. Kansas, as an illustration, is covered by three or four of these rainfall strips running north and south. Its annual rainfall varies from about 17 in the west to 37 inches in the east. As we approach the center of the United States, the rainfall pattern shifts from longitudinal strips to more nearly latitudinal ones. In eastern United States we must add temperature as a factor in the climatic pattern since temperature may alter the rainfall’s effect.
The ratio of rainfall to evaporation suggests that the Cornbelt has enough rainfall for liberal soil construction, but not serious soil destruction through leaching.
The rainfall weaves itself into the more complete climatic pattern if we superimpose on it the forces of evaporation. If, therefore, you will take the rainfall in inches annually, divide it by the evaporation from a free water surface also in inches per year and multiply it by 100, you will have the percentage relation of rainfall to evaporation. Areas of constant figures may be marked off. For example, along one line we may have only 20% as much rainfall as there is evaporation. Therefore, as the rainfall strikes the rocks, it soon evaporates. It doesn’t go in deeply to break up those rocks or to carry down and through any of the products of that decomposition. The western portion of the United States is said to be “arid”, because the rainfall is so much less than the evaporation. There is no washing out or leaching of that soil of great significance. However, in Missouri, Illinois, and Iowa, or in the Cornbelt, with its rain coming in the summer when there is a high evaporation, the rainfall comes in ample amounts to break down the rocks. But instead of it going down through to deplete the soil, it evaporates and leaves the residues to saturate the clay. These climatic conditions give us a productive soil. Out in western United States these forces are not in such a fortunate combination. The ratios are not high enough. And then in the eastern part of the United States. The rainfall is far in excess of evaporation and the figures are above 100. They have so much rain there that the soil is broken down and the products removed by leaching them down through the soil.
Figure 5. The climatic and vegetational soil groups (after Marbut 1935) suggest the basic pattern of food production and thereby a pattern of deficiencies. Soils under construction give us the West with proteinaceous, mineral-rich food products. Soils under destruction give us the East and divide it into a North and a South with carbonaceous food products.
Climatic soil pattern gives us our West and East and our North and South.
It is the pattern of the climatic forces that puts the Cornbelt into the mid-western region and into the prairie group of soils. If we view the map of soils of the United States, which was made before the Russians gave us the understanding of the climatic forces developing the soil, we see that the soil pattern is the same pattern as we get by superimposing the pattern of the evaporation-ratio over that of the rainfall. The soils divide the United States into an East and a West. We haven’t been talking about the people of the East and West without some real provocation for it. People are different because they are on different soils. It is the soil which has divided the eastern portion of the United States into the North and South. That division line wasn’t drawn by color lines of the different peoples. It was the color lines in the soil because those in the South are red and those in the North are grey. The red soils of the South and the tropics have a clay that does not hold nutrients. It doesn’t hold any soil acidity either. So the South has said “we don’t have any acid soils and therefore don’t need lime to fight it.” But they surely have been needing lime badly to provide them with calcium, when so many southern mothers tell you that each childbirth costs two teeth. As we look at the climatic soil pattern, we begin to understand some of our deficiencies. And then if we give close scrutiny to the soils of the central portion in the United States, and likewise to the drier western portion that has allowed the winds to pick up the unweathered mineral materials and waft them eastward as a scattering of blessings regularly on the Cornbelt, some of the food situations and deficiencies in feeds calling for supplements will explain themselves readily.
Soils in the West are under construction, in the East under destruction.
In a traverse of the United States from zero rainfall in the West to the East there is an increase in the force of weathering as we go eastward. Weathering starts with the rock and makes soil, which is nothing more than a temporary reststop of that rock on its way to the sea. As that rock breaks up, more and more under higher weathering forces, it makes more clay and also makes a better soil in terms of nutrition. And as weathering increases there is still more clay, but when the rainfall reaches the amount of 35 inches in the temperate zone it represents the maximum for soil construction. This holds true whether it is in the north with low temperatures, or the south with higher temperatures. (Note–Graph superimposed in Fig. 4. Ed.)
One can go anywhere in the world and use this pattern to guide his understanding of the soils and their value in nutritional qualities of the foods and feeds. When there are about 35 inches of rainfall in the temperate zone there is the maximum of breaking down of the rock and the minimum relatively of washing the products away. This permits the maximum loading of the clay with the exchangeable nutrients so that the plant can come in with its roots and feed itself abundantly. And then as we go east in the United States with still more rainfall, weathering is washing the nutrients off of that clay. The reserve materials and rocks in the soil are so thoroughly weathered that they do not restock the clay and the humus colloids. There is left the sand and silt, but they consist of the insolubles, the permanent quartz. It is in the central United States and east, thereof, that soil acidity comes pronouncedly into the soil pattern. As one goes to the southern states, the soil acidity becomes less because the soils contain a different clay.
That, in brief, is the pattern. With mounting soil construction, there goes increasingly better nutrition. More intense climatic forces represent soil destruction in terms of nutrition even though the body of the soil still remains. In our westward movement initiated by the Pioneers, we have been exploiting the accumulated organic matter. It was that exploitation that permitted us to push westward. And so we have left in our wake mainly the inorganic soil residues with dwindling power to produce. It isn’t so surprising then that now that we can’t go westward much farther, we are come face to face with problems of nutrition in the United States.
Soil construction favors proteinaceous, soil destruction carbonaceous, quality of vegetation.
If one recalls, for example, the areas of the original forests or virgin woods we are reminded forcefully that woody crops were all those soils would grow naturally. Nature was growing wood in the colder acid soils of the Northeast. She was growing wood in the leached soils of the South, and in the higher altitudes of the West where the rock has not yet been formed into the soil. And so when there is not much soil as yet constructed, or if there isn’t much soil left in terms of destruction, the best that nature can do is to make carbonaceous products. But in those regions where the soils are only partially weathered, and consequently fairly well saturated with plant nutrients, it is there that the grasses abound.
The original productivity levels of our soils were indicated by the experiences of the Pioneers. When they landed on the well-wooded eastern coast their search for food was rewarded by the find of a few turkeys. When they found those, they were so thankful that we have had to be thankful for them every year since. But when the Pioneers came westward to the grassy plains, they found the buffaloes of massive bone and brawn roaming that region in thundering herds. Low rainfall and soil under construction were growing protein abundantly, high rainfall and soil under destruction growing mainly carbonaceous products.
If one catalogs the virgin vegetation of Kansas, as Dr. Schantz pictured it, by starting from 17 inches of rainfall in western Kansas and going eastward to 37 inches, it is clearly evident that more rain represents more crop. That is a simple fact every farmer argues, namely that he would grow a larger crop if only he had more rain. Ask yourself, though, what is the nutritional quality of the crop that is growing as the tonnage is increased by more rainfall. It is well recognized that short grass is the crop in western Kansas and tall grass in eastern Kansas which we are prone to attribute to more rainfall. The soil also varies in going from western to eastern Kansas. The lime, which is found at one foot depth and is one foot thick in western Kansas, is no longer visible in the soil profile in eastern Kansas. In eastern Kansas the roots of plants are going down deeply into a wet soil, but they are finding a soil that has been highly leached and the plant nutrients, including lime, have been highly washed out.
Figure 6. A traverse across Kansas from 17-inch rainfall in the western part to 37-inches in the eastern part, showed its virgin vegetation increasing in bulk with increasing rainfall. The soils were also more highly developed giving different root pattern and different feeding value to the forage when the grass chosen by the buffalo was not that of maximum tonnage yield per acre. The buffalo recognized good qualities and deficiencies in his diet. (Drawn by H. L. Shantz).
It was in the western portion of Kansas that the short grasses grew which were eaten by the buffalo so regularly as to be called “buffalo grass.” Those were the soil regions over which the buffalo roamed north and south extensively, but not east and west very far. There were no obstructions against his going east in Kansas when the rivers there run in that direction, and when Kansas was a great prairie. But he wasn’t interested in tonnage increase per acre as we are when sales are made by quantity and not by quality. He wasn’t interested in the products grown on highly weathered soils. Instead he was interested in high concentration of minerals and protein that are built into the short grass of which every mouthful counts.
Unfortunately, we have scarcely shown buffalo sense in evaluating our agricultural output of food products. We have been concerned with the tonnages instead of the nutritional value. What was the buffalo area is the same area where our cattle today multiply themselves. It is from that area that cattle are shipped eastward to be fattened by crops from those soils that have fattening power rather than much growth-producing power.
The human food product of Kansas, namely, the wheat, fits into the same category of proteinaceous or carbonaceous according to the degree of soil development. The protein of the wheat grown in Kansas builds up in concentration as one goes westward across that state. This phenomenon has always been explained in terms of the decrease in rainfall. This might seem a reasonable explanation when according to the survey by the United States Department of Agriculture in 1940, there was an increase in the protein from east to west. The lower or southern tier of counties across Kansas, starting in the extreme southeastern corner, showed a steady increase in protein from 10 up to 18% in crossing the state westward. Such concentration of protein is not a matter of the wheat growing in a dry season. Instead, it must find its explanation in the soil conditions that elaborate much starch and convert little of it into protein in eastern Kansas yet give big yields as bushels per acre, while in western Kansas the late delivery of nitrogen in the season converts starch into protein and thereby less bushels per acre.
We have not given much thought to the fact that in going westward it is the soil that causes plant processes to shift from those given mainly to making and storing starch, to those making protein and consequently burning much of their starch in running that process. When plants make only starch they can readily make big bulk as yield per acre. Failure to recognize these facts has been the occasion for a controversy on wheat quality between the producers and the millers of wheat and the bakers in Kansas. The recent past five or six years have given high rainfall for Kansas. They have also given tremendous yields of wheat. But at the same time the fertility of the soil was being exhausted so seriously by those large yields that the wheat was making mainly starch. The farmer was getting bigger yields while the miller was complaining of the declining quality in the low protein concentration. The baker, too, was unable to get the large loaf from little flour, since it is impossible to lighten the loaf of bread by means of yeast gas and at the same time hold the water to give it weight unless the flour is rich in protein. Consequently the bakers complained that the farmer wasn’t growing the proper variety of wheat in order to keep up the baker’s volume of business. The farmer reported his volume as bushels per acre on the increase and satisfactory. Here was a controversy between two groups provoked by a problem common to both of them, namely, the decline in the fertility of the soil that should call for the interest of both groups in its conservation. Such situations call for attention to our soils in order to grow proteins that satisfy instead of starches that merely stuff the body but give us hidden hunger.
Pattern of Plant Composition Suggests Deficiencies.
The pattern becomes a bit more specific when we consider the chemical composition of the plants…it was possible to study thirty-eight different plants adapted to that region and note their chemical analyses. There were thirty-one cases of different plants that are native to the soils farther east where they are only moderately developed, and twenty-one cases of plants that are native to the soils of the East, including the soils of the South, that are highly developed. According to the analyses of these plants, their contents of potassium, calcium, and phosphorus added together as an average amount of 5% for the plants on the less weathered and less developed soils. As we go eastward and southward, the contents of these three elements go down to 4% for plants on moderately developed soils, and then drop to the low figure of 2%, on highly developed soils. Now, we might point only to the mineral situation and say that these plants are hauling more minerals as they grow on less highly weathered and more fertile soils. But they are also manufacturing many more of the complex synthetics that you and I, located as we are at the top of the biotic pyramid, need to build our complex bodies. Consequently, we find increased woodiness and increased starchiness of our food crops as the soils are highly weathered under the higher rainfall and higher temperature. If we travel in the other direction, from east to west, from highly weathered to less weathered soils, we find proteinaceousness and mineral richness representing higher food values.
Protein Content of Wheat–Kansas 1940. As indicated by pre-harvest survey conducted by Agricultural Marketing Service, United States Dept. of Agriculture.
Figure 7. A traverse across Kansas in 1940 from its low rainfall in the western part to the higher rainfall in the East revealed declining protein concentration in the wheat.
While plant composition is going down… more rapidly than the calcium. As the plants range from soils slightly developed to those highly so, their potassium and phosphorus contents showed a drop from 2 down to 1, but the calcium took a corresponding drop from 7 down to 1.
Here in the changed plant composition in relation to soil composition is reason why in humid soil regions we need to put calcium on soils first in order to have them provide mineral-rich proteinaceous crops. Later we come with the phosphorus and the potash as soil treatments. These are the three mineral constituents that stand topmost in our fertilizer program. We got them, strangely enough, through the art of agriculture long ago rather than through the science of modern agriculture. Calcium is and has been at the top of the list of these necessities. But, unfortunately, we were entangled in the false belief that it was the acidity in the soil rather than deficiency of fertility there that was dangerous. In order to attack that false reasoning, some calcium as a chloride was applied as a streak across a field of soybeans many years ago. Calcium chloride will not neutralize in the acid soil, instead it will add hydrochloric acid to the soil. But even though we put hydrochloric acid along with calcium into the soil, the crop was improved by adding calcium in this form. This did not remove the acidity. In fact it made it worse. Yet it improved the crop growth. For years we have been led to believe that soil acidity in itself is terrible. It is terrible mainly because so much of the fertility has come out before so much acidity can come into its place. Where the soil treatment was calcium nitrate, this salt of nitric acid also improved the crop. This and the chloride gave crops as good as where calcium hydroxide was used to neutralize the acidity at the same time that it was providing calcium.
And so, as agronomists, we must confess that we were reasoning wrongly. Because we had some simple little gadget, like the hydrogen electrode, which we could push into the soil and measure the concentration of hydrogen, we were arguing that the soil acidity was the cause of the crop failure because acidity of the soil was going along with it. This is a characteristically common type of fallacious reasoning, namely, ascribing cause to one of two contemporaneously associated phenomena and the wrong one of the two. We were putting on the carbonate to neutralize acid, but at the same time, unwittingly, we were putting on calcium to feed the plant. We emphasized the neutralization of acidity instead of the nutrition of the plant as the beneficial effect. We were therefore delayed many years in our clearer thinking about calcium as a nutrient for plants, and through them for animals and man. Calcium as a deficiency is late in getting recognition.
Crop bulk as criterion of soil productivity invites deficiencies.
The calcium-potassium ratio, to which reference has been made, has given us a pattern of the protein possibilities in the crop. If Nature, under less rainfall, has left much calcium in the soil, we have a proteinaceous crop. If the soil is under higher rainfall to give a small amount of calcium in relation to the potash, then we have a carbonaceous crop. The validity of this belief, namely, that a liberal supply of calcium in the soil in relation to potassium represents production of crops rich in proteins and minerals, while the reverse relation gives crops high in carbohydrates–thereby low in proteins and minerals–was tested. Soybeans were grown with increasing amounts of potassium available in the soil and associated with constant amounts of calcium. Three ratios of calcium to potassium were used while all other nutrients were liberally supplied. Increasing the potassium increased the forage yield to a maximum of 25%. This fact would draw ready applause for an experimenting agronomist. Such work can win funds in support of it as research. But the buffalo of the western plains didn’t evaluate herbage in terms of bulk. Our livestock does not use that criterion either. Hence, while increase of bulk may appear laudable, fixing of our attention on bulk in relation to soil fertility has been leading us to grow more crops with serious deficiencies as feeds.
Chemical analyses were made of the forage. The nitrogen content of the smallest of the three crops was 2.8%; of the intermediate crop 2.5%; and of the largest crop 2.19%. While we increased the bulk 25%, we reduced the concentration of nitrogen, and therefore the protein, by more than that figure. So that the greater amount of total protein was not in the largest but in the smallest crop.
If a cow were to get the same amount of protein in the largest crop in contrast to the smallest she would be compelled to take about five mouthfuls instead of four. Most of us are familiar enough with cows to know they can not increase their intake by 25%. Consequently the cow is really going to suffer some deficiencies. She can not handle more bulk in order to get the necessary protein.
Figure 8. By keeping calcium supply constant but increasing the potassium a 25% increase in tonnage was obtained. However the protein content of the plants dropped by more than 25%. The small crop had twice as much phosphorus, three times as much calcium as the bulkier crop. Soil fertility sets the pattern of composition.
The phosphorus concentration, by analysis, was .25% in the small crop; .18% in the intermediate; and .14% in the largest crop. Assuming that the cow could digest it completely, she would be compelled to eat approximately twice as much of the larger crop to get the same amount of phosphorus. In the case of the calcium, this was approximately .75% of the dry weight in the smallest crop and only .27% or about one-third as much as in the largest crop. Can any cow increase her consuming capacity by three times? We can’t expect her to become a hay baler.
We need to be concerned not only with the bulk of the crop, but also with the synthetic operations of the plant in using the fertility elements from the soil to convert the carbonaceousness over into the proteinaceousness. Those processes make foods of value in terms of growth instead of only fuel. Those are the features that make “grow” foods instead of merely “go” foods. They must be more generally appreciated if we are not to invite nutritional deficiencies more commonly.
Some research studies were made to illustrate this conversion of carbohydrate into protein by the plant. A legume crop was thrice planted on a series of soils with potash increasing in relation to calcium, knowing that more potash in relation to calcium makes the plant a producer of carbohydrates rather than of protein and also increases the yield. The first of the three successive crops on the soil was not given bacteria. Consequently this legume, limited as it was to only the nitrogen in the seed, could not convert air nitrogen into protein. That first crop had no more nitrogen in it than was originally in the seed. The crop built a great bulk, yet the smallest crop in the series grown by less potassium had the same amount of nitrogen as the larger crop. The second of the crop succession was inoculated with nodule-producing bacteria so that it became a protein synthesizer instead of being only a starch producer as was true of the first crop. This growth exhausted the soil fertility seriously as protein-producing crops must; consequently the third crop was limited by the soil fertility and, like the first crop, was a starch producer.
The first crop gave the highest tonnage yields, the third one was next in order, and the second crop gave the lowest yields of all. In fact, the third crop was more than 30% higher in weight than the second crop, and yet it was the third successive crop in the course of exhausting the soil. Crops are commonly judged in terms of tonnage yields per acre. Little thought is given to the fact that crops making only carbohydrates build bulk quickly but those converting the carbohydrates into proteins do not. The first crop had a low sugar content, but a high starch content. Those plants were converting the sugar promptly over into starch because in the absence of soluble nitrogen and legume bacteria there was no nitrogen hence no way to convert the sugar into protein. The second crop, which was inoculated, had a higher sugar content, but it was not being converted into starch of which the concentration was very low. These facts suggest that the sugar was being converted into protein. Analyses showed that a goodly amount of nitrogen was taken from the atmosphere. The third crop yielded a large amount of bulk again as did the first crop. This had a high content of sugar. It was inoculated and was making and piling up sugar that seemingly should have been converted into protein. But the two preceding crops had exhausted the fertility of the soil so that the best this final crop could do was store starch. Consequently the third crop was of a high starch content and high yield of bulk.
Crop bulk as the criterion for a crop leads us to choose those crops which are making carbohydrates rather than making proteins and other nutrient complexes with more than fuel-food values. High yields as bulk may therefore give us deficiencies. Crop quality in terms of nutrition rather than mere tonnages should be the criterion for selecting crops.
Vegetables also invite deficiencies according to soil growing them.
Spinach was made the subject for research into its chemical composition as influenced by the fertility of the soil. Spinach as a vegetable green is probably one of the most debated elements in our diet. Some argue that they like it, others that they do not like it. Chemically considered, there is good reason why some people do not like it. Spinach may well be classified as one of the hypocrites of the garden plants. It can put up a fine green appearance and have less calcium, for example, than most any other garden plant used for greens. Therein may be the reason why some people love it and some people hate it. The people who love it probably get the spinach that is high in calcium and those who hate it probably get the spinach that has little calcium but is high in oxalate.
Spinach was grown experimentally in order to get at the question of soil acidity, which in terms of calcium for spinach is not so dangerous. In fact, soil acidity is beneficial. Two soil series were arranged to provide increasing amounts of exchangeable calcium by units of 3 milli-equivalents to a maximum of 12. All the other nutrients were offered in constant but ample amounts. In putting the calcium on the soil the first sexies of soils was given it in the form of salts that left the soil acid. The second series had exactly the same preparation, but the calcium was put on as oxides and hydroxides. These forms made the soil neutral. Thus there were increasing supplies of calcium and constant amounts of all the other nutrients in one series of soils that were all acid in reaction, and another series of soils as a duplicate except that the soils were all neutral.
As the soil was left acid that grew the spinach, the increasing amount of calcium applied on the soil gave a corresponding increase of concentration and total of calcium in the crop. It also gave an increase in magnesium, though the magnesium was applied in constant amounts to all the soils. It may be well to point out here that calcium is the one element which moves many of the rest of the elements into the crop. It moves the magnesium; and it moves the phosphorus because it is the “keeper of the gates”, as it were, into the roots of the crop. As a matter of fact, its deficiency lets some nutrients go from the plant back to the soil. Consequently we may be growing crops that have less nitrogen, or less phosphorus, or less potassium in them than was in the planted seed.
Spinach manufactures oxalic acid. This compound contains no elements of soil fertility. Oxalic acid is not desired by all folks because it “puts your teeth on edge”. Rhubarb gives the same sensation but we eat rhubarb for its acid. But few people care to eat spinach for that same effect. The oxalate unites with the magnesium and the calcium to make them insoluble and indigestible. In the case of the spinach grown on the acid soil there was so much calcium and so much magnesium in the crop that the oxalate content, even though seemingly high, was not high enough to make all of the magnesium and the calcium indigestible. Therefore there were significant amounts of the calcium and magnesium in the spinach that were soluble and digestible. The spinach grown on neutral soil did not take increasing amounts of lime in proportion to the increasing amounts of calcium applied on the soil. Nor did it take increasing amounts of magnesium as were taken in the other case. Spinach grown on the neutral soil had so much oxalate that this was more than enough to make insoluble and indigestible all of the calcium and all of the magnesium taken by the crop. Had one fed that spinach to an unsuspecting baby and given some milk along with it, that mixture would have not only been deficient in terms of digestible calcium and magnesium from the spinach, but it would even have made indigestible some of the calcium in the milk.
In dealing with this matter of nutrition, our thinking must go back to the soil that grows the crop. We must understand some of these fundamentals by which the nutritive value is controlled. We can not be certain of vegetables as sources of mineral elements merely because of vegetable name and reputation. Vegetables may encourage deficiencies because of the fertility deficiency of the soil growing them.
Figure 9. Plants call for a balanced diet for their best growth, if they are to prevent deficiencies in the diet of the animals and man. Variations in the available nitrogen, phosphorus, and calcium on the soil brought wide variations in this tomato crop.
Soil exhaustion means going to starchy and woody food products.
So much has been said about the soil-conserving virtues of grass agriculture and livestock farming as to leave the impression that such practices keep lands from serious depletion of their fertility and productive capacity. Yet forty years of grazing alone in a Santa Rita Mountain Valley were sufficient to change the native grass vegetation to mesquite bush of no grazing value. In 1903 that valley was a temptation to the cattlemen because it had a nice, luscious growth of grass. They brought in their cattle. Instead of allowing the accumulated soil fertility in each crop to drop back as nourishment for the next one, and to bring a little more of mineral decomposition into that cycle and thereby build it larger, they brought the cattle and annually hauled off much of that grass by means of them. By 1943 they marvelled at how one lone mesquite bush present in 1903 could have taken. that whole valley as a mesquite infestation by 1943.
By rotating the fertility unmolested Nature was producing proteinaceous vegetation, but when man began hauling off that crop Nature switched over to the production of woody vegetation. It was one which could send its roots deeply enough into the soil to get the necessary minerals and one which is equipped as a legume to take much of its needed nitrogen from the air. And so while civilization has been moving westward across the United States, the mesquite is moving westward across the State of Texas to take over the prairies. Is it any wonder that in the wake of that fertility exhaustion the soil should shift from producing proteinaceous vegetation to the production of woody vegetation? Is it any wonder that the “soft” or “low-protein” wheat is moving westward with the depletion of soil fertility? Thus we are bringing out and into prominence the pattern of deficiencies because starchy wheat will not feed us any better than wood will feed the cattle.
Figure 10. Virgin grass in a valley in the Santa Rita Mts. was a temptation to the cattlemen (upper photo) in 1903, when it grew rich grass, but crop removal and depletion of organic matter brought a woody growth of mesquite (lower photo) in 1943. Photo courtesy US Forest Service.
Animals are connoisseurs of feed and not mere mowing machines.
The grazing cow is not merely a mowing machine. If one observes a pasture it is common to find that she hasn’t done a clean job of harvesting the grass crops. Instead she has been selecting and balancing the carbonaceous vegetation against the proteinaceous according to the nutritive ratio that she needs in order to deliver a calf or to provide milk for it. When the pasture crops are not completely taken by the cattle we emphasize the necessity to mow the pasture. We say much about the necessity of having successive pastures during the grazing season. Instead of thinking about juggling the crops as pasture successions, we should be thinking about undergirding the cow’s selection of her herbage by producing it with those particular qualities she needs as nutritive values. Our animals by their appetite are searching through the different crops in mixed pasture herbage, balancing their diets in proportion as their body needs may represent a fattening performance in one season, a foetus-developing performance in another, or a milk-giving performance in still another season of the year.
We haven’t been ready to believe that the cow will select and graze first the barley where 200 pounds of fertilizer were applied and will disregard the same crop where 100 pounds only were applied. But such was the observation of Mr. E. M. Poirot, a farmer of Missouri. The cow is a better chemical assayer of the soil conditions than we are in the laboratory. It would be necessary to call on the spectrograph and other equally refined instruments to find the difference in the soil between 100 and 200 pounds as applications per acre. And yet the cattle detected a case of that kind for several successive years. That fact was demonstrated by the cattle in selecting one among the four haystacks in 100 acres of virgin prairie meadow. In the early spring 1936, a 4-acre porti(was treated with different fertilizers carrying calcium, phosphorus, nitrogen and other essentials. The grass species were enumerated during the summer. Sample yields were taken. Chemical analyses were made. There were increases of about 5 to 7% in many of the different ash constituents, and about that much in yield.
In the late summer the grass crop was dried into hay. About 25 acres of hay were put into each one of four haystacks. The four acres that had been given soil treatments were promiscuously included in one of the haystacks. The cattle were turned into the field in the late fall to consume the haystacks. The owner reported in 1936 (December) that the cattle had passed up the three haystacks and had eaten first the fourth one in which there was the hay from the four acres of treated soil. There were no additional treatments put in the soil after 1936. The grass was made into hay annually as four haystacks. The hay from those four treated acres, along with that from about twenty-one acres given no soil treatment, went into a stack at one end of the field annually thereafter. This was the regular one for careful observation. The cattle ate this one haystack first in 1937, and each year thereafter through 1944 for eight years.
The eighth crop provided an interesting discrimination by the cattle. In that year when the stack bottom was started on which to build up, it was not made large enough. After the four acres, along with hay from untreated acres had gone into the stack to the limit of height, considerable untreated hay was left. Consequently the balance of the hay of 25 acres was put at the end of the stack to extend it. The cattle were turned in as usual in November. As they had done regularly since 1936, the cattle disregarded three of the haystacks. They crowded about the one containing the hay from four acres given soil treatment as part of the stack. They cut this stack in two, selecting first the main portion containing the treated hay. After they had consumed this part they still worked over the trampings before they took to the other stacks. When this remnant was all that was left they went to the other stacks. Here then after the ninth successive crop, the cattle were still recognizing the quality of the hay induced by the small amount of soil treatment that was not over 600 pounds per acre.
Figure 11. Cows Select Hay From Fertilized Soil– Hay from soil fertilized in 1936 was still being selected in 1944. The haystack was cut in two. The part taken first consisted of a mixture of which about one-fifth had grown on soil given fertility eight years before. (Upper picture). The remnant consisting of hay from soil given no treatment was no more enticement later than the three other stacks of hay from untreated soil. (Lower picture).
Even the hog, supposedly such a dumb beast, has a very discriminating taste. A Missouri farmer had 40 acres of corn into which he put his hogs to take the grain as feed from the field rather than harvest it in the usual manner. They went into the field and seemingly disappeared. He didn’t see any indication that they were eating the corn until a neighbor told him the hogs were doing very nicely in the field corner near his farm. The hogs had been going through the 40-acre field daily from the water to this chosen corner. The farmer remembered that several years before he had tried to grow some alfalfa in that corner. It had been limed and fertilized but had been forgotten.
We commonly think the hog has no discriminating power, but in experimental work the hog’s appetite can be a helpful tester. One can put the different grains into the several compartments of the self-feeder and the amounts the hogs take are an index of their choice. Hogs have demonstrated consumption of one kind of corn as low as 10% and as high as 100% of another grain alongside according as the soils growing them were given different fertilizer treatments.
Insects, too, are discriminating in their attacks on vegetation fertilized differently. Varying amounts of nitrogen were applied on the soils for a series of spinach plants. These applications were a supplement going with increasing amounts of calcium. All other nutrients were generously applied. The thrips, which is an insect that attacks spinach, cut the leaves wherever the crop was given low amounts of nitrogen, but left untouched the leaves of plants grown on soils high with nitrogen. The experiment was replicated ten times. Two rows of spinach with attack by the insects alternated with two rows free of insects in repetition ten times. It is an old saying, namely, “to be well fed is to be healthy”. Parallel with that seemingly one can say “to be well fed is to ward off the insects”. At any rate there is the suggestion that the pattern of declining soil fertility is the pattern of plant diseases and insect troubles with plants.
Figure 12. Healthy Plants Ward Off Insects–The insect attacks were pronounced on spinach suffering a deficiency of nitrogen in the soil (two rows on left), but were missing where ample nitrogen was put on the soil (two rows on the right). More calcium made the nitrogen more effective in warding off the insects.
Animal deficiencies go back to soil deficiencies.
Much has been said about the mule, especially about its fastidious appetite. Its progenitor, the donkey, is similarly cataloged. In our problem of raising donkeys we have forgotten that the donkey requires feed grown on calcareous soils. The misfortune that befell a young donkey illustrates the case. A young jack of fine breeding was moved from the region of Missouri that is famous for jacks, or from the region of the farm that is known as the “Limestone Valley Farms,” and taken to western Missouri that is supposedly famous for bluegrass. As a result of that transfer, this donkey of good breeding or of a fine pedigree developed a severe case of rickets. The pedigree could not overcome poor feeding. While breeding can bring about certain qualities and tolerations, one can’t breed either animals or plants to tolerate starvation. Breeding for such toleration, much like a race of bachelors, goes on for only one generation.
Figure 13. Soils Bring On Deficiencies–Treatments of forages by feeding animals revealed that soil treatments correct deficiencies, not only in the soil fertility but in the diet of the animals.
In the beef cattle business (one of the phases of agriculture in which a state like Missouri is highly active) the fertility pattern exercises decided influence. There are many steers purchased in Texas, in Oklahoma, and adjoining states, and moved to the cornbelt for fattening. All too often the farmers in this business say they had “bad luck,” because some of the steers “went down” just about the time they should have been ready for market. Now what’s the trouble involved? The experiences of one of our Missouri farmers gave a good illustration of the soil fertility conditions involved. He had brought some Texas steers, weighing about 600 pounds each, to his farm in northeast Missouri. It is in the more level region with some exhausted soils in the area where troubles in breeding herds are also all too common. He had 43 head, and at about the time they should have been going to market, one of them “went down” on its hocks with the symptoms suggesting that it had been hamstrung. This animal lingered along until it was much emaciated when the second one “went down,” with what suggested paralysis of the hind legs.
Now this farmer had been feeding cattle for some forty odd years. His father ahead of him had fed cattle, too. They had accumulated much experience in cattle feeding. But while they were accumulating experience, they were also bringing on soil destruction on their own farm. These animals were fed on home-grown feed. This included a peck of corn, a sheaf of oats, some cottonseed supplement, and some legume hay. The hay was soybeans which supposedly grow well on “acid” soils.
About the time his second steer “went down,” calls came for some of the extension men to go out to help in the situation. Before the veterinarian arrived the third steer was down. Now what was happening? The tendons had pulled out of the soft bone where the animal was hamstrung. The pelvis had separated from the vertebrae and had paralyzed the whole rear part of the second animal. While these animals were laying on fat, they were not building the calcium and the phosphorus into the bones. Their bone structures were so soft they were letting the animals “go down.”
The differences in the soil fertility represented in the life of these animals are as contrasting as the animal behaviors. One region, namely, the same region where the buffalo roamed, had grown these animals. That area during the life of the young calf couldn’t give enough mineral and protein reserves to permit putting on only extra fat and getting that to market. Such experiences in the so-called “cattle business”–which is mainly a buying and selling rather than a production activity–come all too often. They are serious disasters because we do not realize that even in the fattening of the animal one must provide it with carrying power (for the load of fat) by building well the bones and the protein at the same time. Evidence is accumulating but, unfortunately too often coupled with serious disaster, to compel the realization that the deficiency troubles in animal production are not so much a matter of better breeding but one of better feeding. Feeding is not a problem of combinations so much as a problem of quality “grown into” the feeds. Feed deficiencies are showing themselves as fertility deficiencies in the soils that grew them.
Animal improvement can be brought about by remedy of soil deficiencies.
That applications of calcium and phosphorus to the soil transmit their beneficial effects through the feed was demonstrated experimentally by feeding hays from treated soils to some sheep. By combining some soybean and some lespedeza hays, both grown on the same soil treatments, there was sufficient hay to grow lambs for sixty-three days. Seven lambs were fed on hay that had no soil treatment; seven on hay that had been grown on soil that had phosphate; and seven on hay grown where the soil had been given both phosphate and lime. The sheep ate exactly the same amount of hay per head per day and were given exactly the same supplement.
In terms of bulk the feeds were all equal, but in terms of quality, as demonstrated by the growth of the sheep, these feeds were widely different. Where the feed had been grown with no help in the soil, the lambs made a gain of eight pounds per head in 68 days. Where they had been given the help of phosphate on the soil, they made a gain of 14 pounds. Where they were given the still better undergirding by means of lime and phosphate on the soil, they made a gain of 18 pounds. In other words, between 8 and 18 pounds of lamb growth was the improvement brought about by the mere application of a small amount of soil treatment known to remedy a deficiency. Animal growth is not a matter of bulk of feed, but one of feed quality grown in by the fertility of the soil.
Figure 14. Shinbones of calves reveal differences according to the soils growing them. Deficient soils make small, soft bones (top), treated soils make heavy, strong bones at the same age (bottom).
We may well think of food quality in terms of larger soil areas, as well as of plots and fields. The soils of Missouri, for example, divide themselves very distinctly into five major regions. There is the southwestern portion of the state that is a duplicate of eastern Kansas. The Eldon silt loam is a typical soil there. A portion of northeastern Missouri is level prairie, and its soil is Putnam silt loam. The Ozarks are mainly Clarksville soils. The northwestern part, or the corn section, is mainly Grundy silt loam. The southeastern lowlands, or the cotton section, are covered by a soil series known as the Lintonia. Experiment fields have been located on each one of those soil types It happened that lespedeza was growing under the same general conditions one year on each of these fields with both the treated and untreated soils, The lespedeza hay was harvested in these different regions of the state, brought to the Experiment Station, and fed in ten different lots of ten rabbits each. The rabbits were carefully selected and distributed as litter mates and as to sex in order to make the lots as uniform as possible. The ten rabbits in each pen were like every other ten as nearly as they could be selected. They were fed the respective hays for a period of about eight weeks.
One might well argue that these animals represented a constant breed at the outset. But the appearances of the rabbits at the close of eight weeks on the hay from different soil regions of a state suggested that they were of different breeds. A wide variation in body size characterized those fed on hay from untreated soils. Such differences suggest that each soil area of the state will bring about certain characters quite different from those of the animals in another area. Hay from the soils given treatments grew animals better in size, more uniform in appearance, and less in difference by soil areas.
In spite of such differences brought on by variation in soils within even a single state, we believe we can maintain a constant set of characters knowing characters of the breed. Extensive breed records are being kept in the belief that a constant set of characters is being maintained. All this goes on in disregard of the force of the difference in fertility of the soil which is literally changing the breed in the short time of a single generation.
The body physiology of the animals also was different, according to the soils, if one examines the bones, for example. These showed differences in diameter, density, thickness of the walls, breaking strength, calcium-phosphorus ratios, and many other properties.
If one makes an examination of the wool of sheep fed on feeds grown on different soil, wool differences are evident. The wool is a physiological product of the nutrition of the animal, just as are bones, blood, or other body parts. If the sheep suffers deficiencies in feed, wool fiber is apt to be thin, or will break easily. The wool of sheep was studied according to soil treatments used in growing the feed. The wool of sheep on soils deficient in calcium and phosphorus was almost free of the wool fat. The animals were not excreting freely those fats in the skin that make the wool greasy. Quite in contrast, the sheep which were fed hay from soils treated with lime and phosphate–and were making the better gain of 18 pounds while the others gained only 14–produced a greasy wool, or one full of “yolk” as the sheep men speak of it. When these different wools were put through the scouring process, the originally more dry, or nearly fat-free, wool seemingly gelatinized, cemented itself together on drying, and could not be carded without being broken into bits. The wool of the other sheep lent itself to carding and would be normally a regular fluffy wool specimen. These differences in the wool are different physiological manifestations because differences in plant physiology and differences in soil physiology occur farther ahead in the chain of events responsible. The improvement in the animal physiology and animal product resulted from the remedy of the deficiency in the soil.
Figure 15–This donkey, as a native of drier soil regions, does well on lime-rich soils. This highly bred specimen developed a severe case of rickets on transfer from one part of Missouri to another.
Deficiencies in the soil brings troubles in animal reproduction.
Reproduction draws heavily on calcium, phosphorus, nitrogen, and other soil-borne essentials for building bone and muscle. That a cow could sacrifice part of her backbone was demonstrated by one of recorded breeding history. She had become a poor reproducer, and died far too early in her life for the noble line of breeding she represented. The crows had picked her skeleton bare and revealed that the separate vertebrae of the middle of her back were not visible. That section of the backbone was perfectly solid instead of being normally flexible. Can we not see that in developing the foetuses and in giving milk, she sacrificed a portion of her backbone in order to supply the necessary calcium and phosphorus while living on soils deficient in these respects? After each calving to rebuild the backbone it was built as a solid section rather than as the five divided vertebrae. She was a poor reproducer, not because of poor breeding but because of deficiencies in the soil fertility. These deficiencies made her a “shy breeder”, for while rebuilding her backbone she scarcely could be expected to be building ova that would be conceptive and keep her calving schedule on the desired regular pattern.
Deficiencies in soil fertility report themselves in the form of troubles in reproduction not only with reference to the cow as mother, but also to the calf in its early life. An interesting case came under the observation of Mr. A. W. Klemme of the University of Missouri, in his agricultural extension work in soils. As a result of his discussion of the subject of soils in relation to animal nutrition at one of the rural meetings, a farmer-owner of a calf reported his troubles with it. It couldn’t get up. He diagnosed the ailment as what is commonly called “hollow horn” or “hollow tail”. He reported his treatment of it by splitting the end of the calf’s tail and putting salt and pepper into it.
Mr. Kiemme’s examination of the farm and feeding situation revealed that no thought had been given to the soil. The farmer had not yet thought he would follow the “newer” soil practices of his neighbor. The mother cow was of large body but not in good condition. Mr. Klemme’s recommendation was that some milk from the neighbor’s cow be given the calf and the neighbor was called in for consultation and favorable agreement.
It was ten days later when Mr. Klemme made the second visit only to find the calf up and taking milk from both the neighbor’s cow and from its mother. It was quickly recovering from its case of rickets. The calf was still carrying the bandage on the end of the tail as testimony of the farmer’s poor diagnosis.
Too often we, like the farmer, let our thinking start from the wrong end. We are diagnosing, as Dr. Price and Dr. Hooton have put it so well, “from the morgue and the grave backward instead of from preconception and conception forward”. Too often it is a situation in which we are treating the symptoms instead of removing the causes of the trouble. Animal husbandry is failing to use the maternity capacity to its maximum by failing to treat the deficiencies in the soil and thus fails to obtain more offspring per mother.
Human deficiencies may also be traced back to soil deficiencies.
The work of Dr. Weston A. Price, under the title of “Nutrition and Physical Degeneration” reports his studies of the teeth among primitive peoples. From it one learns that it is not necessary to go to Hereford, Texas, to find the “town without a toothache”. He found native Africans with excellent teeth, yet they had never heard of a tooth brush or paste. He found them suffering with various tooth irregularities when they took over white man’s food habits by purchases from his store. Dr. Price points out that teeth, as an exposed part of the skeleton, tell of a corresponding disintegration of the rest of the body as they break down.
Physical examinations of our men for the Army and the Navy revealed that the increasing number of cavities in the teeth fit into the soil fertility pattern of the United States. The smallest number of teeth defects were represented by the men from the midcontinent. The numbers increased on going eastward from there. There is a good indication (with nearly seventy thousand cases reported for the Navy) that the pattern of tooth troubles duplicates the pattern of the soil fertility. Deficiencies in teeth, as we may expect of other deficiencies, take their pattern from that of the soil.
Mental deficiency has been related by Dr. Price to defective bone development in the skull. With him we may well raise the question whether defective nutrition may not be provocative of defective minds, since it is as much of a physiological process to think as it is to digest. Insufficient bone growth in the lower skull may give trouble with such vital parts as the pituitary and may occasion troubles in the entire endocrine system. Such irregularities have not been so commonly considered as possible causes of delinquencies and mental irregularities.
Reproduction may be more closely associated with nutrition and the soil fertility pattern than we are prone to believe. Successive children in the family, with increasing body defects, have been pictured by Dr. Price as related to successively lower nutrition of the mother. Have we thought of relating these to soil regions?
Soil Fertility gives pattern to international problems.
One needs only to study the soil pattern of the United States to learn how fittingly it may serve to guide our thinking about some of the international problems. The soil map of the world reveals that the hard wheat belt, as a particular combination of climatic forces produces it in the United States, is replicated in similar climatic conditions for fertile soils in Russia, in several of the outposts of the British Empire and in the Argentine. It is also replicated in Northern China but not in Japan or her former island possessions. It is the soil fertility pattern in terms of potency to grow wheat and meat that nominated the great powers of present day international affairs. It is they, with territories in the temperate zone and moderate rainfalls, that have soils providing good nutrition. World problems are not delineated so much by politics. They are marked out by the soil fertility in relation to efficient nutrition. Deficient soils mean deficient and delinquent countries, in the world family. International problems therefore may well be considered in terms of the map of the soils of the world as the guiding pattern for future thinking and planning for peace.
Summary
Our knowledge of the soil in terms of its origin, its chemical composition and dynamic aspects can now be coupled more closely with plant physiology to help us understand why deficiencies in our nutrition as well as in the nutrition of the plants and animals may be expected. Some dozen soil-borne elements needed by our body are not all commonly present in every soil. Protein is the major problem in more ways than the economic one. Plants struggle for it too, since they require liberal stores of soil elements to build the amino acids from which we construct our proteins. Plants produce carbohydrates generously, but synthesize proteins within the limits of soil fertility. Soil exhaustion, whether by high rainfalls or excessive cropping, invites nutritional deficiencies since plants then synthesize mainly carbohydrates. Animals therefore fit into an ecological pattern according to local soil fertility and humans too must fit unless they move to or obtain foods from distant, fertile soils.
Our soil fertility is giving a pattern via nutrition not only to crops, animals, and human health, but has international implications as well. Food, after all, is the most potent factor of life and it is the soil fertility by which food is provided. Soil deficiencies therefore provoke other deficiencies more far-reaching than one can readily imagine. We shall correct these not by legislative procedures or by political manipulation but rather as we minister to the soil in its wisest and most efficient conservation.
Editor’s note: Since the era in which this article was written, society’s understanding of respectful terminology when referring to ethnic and cultural groups has evolved, and some readers may be offended by references to “primitive” people and other out-of-date terminology. However, this article has been archived as a historical document, and so we have chosen to use Albrecht’s exact words in the interest of authenticity. No disrespect to any cultural or ethnic group is intended.