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  BEFORE extending the application of the Keyline beyond the first simple Keyline of a valley and its uses as a cultivation guide, a discussion of soil and of cultivation methods is undertaken in this chapter. This forms a basis for the presentation of the Keyline methods of progressive soil development.

  Prior to the introduction of the mouldboard plough one of the great problems of agriculture arose from farmers' difficulties in controlling the unwanted growth on fertile soil. The rich agricultural land obtained by clearing virgin forest areas or breaking up the natural fertile grasslands were hard to hold from the exuberant growth of vegetation. The growth made it impossible for the farmer to crop large areas.

  The mouldboard plough, by turning over the soil and burying the unwanted growth gave the farmer better control. He could then hold and crop larger areas of land.

  The advantage of the new power cultivation which was later introduced, lay in the further increased speed to control the unwanted growth. Rubbish was turned under to produce a "clean" soil surface.

  After the earlier slow work to control this growth the new implement inspired a fetish for "cleanness" and "fineness" of cultivation. This fine seed-bed, almost universally acclaimed, produced bumper crops year after year and the rich fertile earth showed little evidence of fertility losses over long years.

  This type of cultivation and the other farming and grazing methods however, were generally destroying natural fertility much faster than the crops which were profitably extracting some of it.

  Eventually, when erosion became a serious menace, some nations undertook an inventory of their soil losses and found that the figures were staggering.

  Gigantic efforts were needed to arrest these colossal losses by erosion.

  Fertile soil was not being washed away, but only those soils which had already lost or were then rapidly losing their fertility were on the move.

  Fertile soil was built originally by processes of absorption, growth and decay, and such soil resists erosion. A change of methods from those that extract fertility from the soil to methods that absorb fertility into the soil is the only way to overcome the erosion problem. A positive change must be made from Extraction Fertility farming to Absorption Fertility farming.

  The first requirement, already stated, is the retention of all rainfall in the land for the production of fertility, and not methods to "safely" allow water to leave the property.

  It is economically unsound merely to prevent erosion losses of poor soil.

  Soil fertility can be built back into the soil in a positive manner so much faster than the natural fertility was lost, that little need be done from the negative standpoint of controlling erosion. The best methods of soil development are the surest means of erosion control. Continuance of these methods will quickly produce as good, if not better, soil than that which originally existed.

  While these methods are being followed, even from the first year, better farm yields will result. Absorption, growth and decay make fertile soil, and the factors which produce the maximum growth and decay can be controlled in farming practices. The needs of the farmer are satisfied at the same time.

  There is little evidence anywhere in nature to support the "take and put" theory of farming where farmers are taught to "put back" into the soil each year what they "take out" in crops. So much of what is taken out is composed of materials that are available in unlimited supply from the sun, air and moisture--moisture alone requiring conservation--that if farmers cease to "mine" the top inches of the soil and farm the land, little if anything else need be put back. Fertilisers should be used when they are necessary, but they are rarely the "first" need. This is true of most of our farming and grazing lands.

  Correct cultivation is a means of progressively improving soil structure and soil fertility, thereby developing a greater depth of fertile soil. Better crop production is incidental to the process.

  The mechanics of the process of soil development whereby Nature built up the great fertile soil belts of the earth are now reasonably well understood by the farmers. Good writers have made of the process an absorbing and fascinating story. Some see in it a miraculous efficiency and give estimates of the time required to build one inch of fertile soil--varying from a few hundred years to ten thousand.

  If the natural process is efficient and the time estimates of even a few hundred years are correct, there is little that could be done by us in the production of soil. However, nature's methods do not take time into any serious account, whereas to us "time" is all important.

  The processes which developed natural fertile soil are capable of control and tremendous acceleration. The dead stalks of plants, slowly laid down by nature loosely on the land surface, decay. This is one fertility process which is capable of acceleration. Each time decaying vegetable matter dries, decay temporarily ceases and fertility processes are slowed down. Processes of decay are increased when moisture is present. This decay, to all intents and purposes, is fertility.

  Man and his machines can stimulate decay and growth tremendously.

  When vegetation is stirred into the aerated part of the soil, decay continues for a longer period. Moisture remains longer to supply the needs of decay.

  Every process and activity in the improvement of soil can be controlled and increased by the farmer, to the continual betterment of his soil. Not all natural soils are fertile--far from it. Where suitable moisture, heat conditions and minerals exist, fertile soil develops in time. There is a certain progression in the development of soil in nature. The growth and decay of primary and simple forms of plant life -eventually create conditions suitable for the growth of better crops and grasses.

  Through the lack of some essential, this process toward the development of fertile soil will cease, or slow down. Thus poor natural soils exist in many areas.

  Vast areas of these poor soils of nature can be made fertile and productive, by supplying the needs to complete their full cycle of development.

  Natural shortages of vital minerals often can be remedied economically.

  Rainfall or other moisture sources can be controlled efficiently, to promote more rapid growth and decay. Great improvement will be made in many of these soils in a year or two. New plants and grasses that will continue and complete a cycle of high fertility can be introduced.

  Plants draw their sustenance mostly from the products of decay, from and with moisture contained as a water film in the "pore" space of the soil. Generally, maximum pore space promotes maximum growth by the greater availability of pore space moisture. The pore space is multiplied by increasing the supply of vegetation for decay and for the production of humus.

  These vitally important factors are increased also by the correct mechanical mixing of vegetation into the surface soil. Correct aeration of the deeper soil and subsoil will progressively convert these to deeper fertile soil.

  Some soil scientists estimate that there are 70 tons of living organisms and other life in an acre of fertile soil. These organism generally work towards man's health and well-being.

  The importance of fourteen five-ton truck loads of microbes in an acre is overshadowed completely by a sheep or two to the acre. The sheep or cattle obviously need constant care, but surely this other "livestock" warrants some conscious thought when it is so vital. All the elements of growth are made available to us by the various processes of the life cycles of this "life in the soil". Soil management can reduce this dynamic force to a low ebb, or tremendously stimulate its activities.

  Fertile topsoil and even very poor soil can be treated as a yeast. Fed and cared for, it increases. Starved and asphyxiated, it dies.

  Processes of decay are the multiplication of soil life. These processes initiate or commence in the presence of moisture, air and heat. All three are necessary. This suggests that a starting point in soil development should be a critical examination of farming practices as to their effect on these factors.

  Past cultivation habits have destroyed soil fertility to the stage where vast quantities of once valuable soil have been lost by destructive erosion.

  Pounding and pulverising, turning and slicing implements have all interfered with and reduced pore space in fertile soil. Soil suffered too much cultivation each time it was worked.

  Extremely fine "seed-beds" are still produced on some farms, almost as if the crop in its growth was expected to devour every fine soil particle.

  Too fine a cultivation destroys the soil's structure, smothers and reduces soil life, thus degenerating the art of soil management into a bandit-life process of fertility extraction.

  Soil fertility need not be "extracted" or destroyed to produce good crops. Crop production is properly a part of an important method in the development of better soil.

  Cultivation can be either the mammoth destroyer of soil fertility or the greatest single means of improving and even the creating of more fertile soil.

  An understanding of the structure and condition of naturally fertile soil and an appreciation of just what is happening, or has already happened, on some major soil areas will indicate logical means of improvement.

  Fertile soil is loose, absorbent and pleasant smelling. It is dark in colour caused by decay in the production of humus. It receives rain quickly and allows it to penetrate deeply. It holds moisture in pore spaces which are found in and around every particle of decaying material and in humus as well as around the mineral particles of the soil. Moisture dries out of fertile soil slowly from the effect of the highly insulating structure of its surface. Deep soil and subsoil moisture is protected from the drying effects of sun and winds.

  There are no definite horizons to the top soil, deep soil and subsoil; one merges gradually into the other and all are subject to a gentle stirring action from the larger forms of soil life and from the action of deep roots which bring nutrients to the surface. There is no sharply defined plant root zone in natural fertile soil. Shallow, medium and deep root growths mingle. Root decay acts to aerate the soil to an appreciable depth via the cavities left by the roots after decay.

  The fluids, acids and gases of the fertile soil act continuously on the deeper mineral particles of the subsoil and rock below, converting these to forms which are later available to plants, and so improve and deepen the soil.

  Soil life flourishes according to the varying condition of food supply--moisture, air, minerals and decaying. plant life. The whole body of the fertile soil is teeming with dynamic energy--growth and decay is continuous and simultaneous.

  Cultivation that is highly successful mechanically in controlling soil for crops also has had the effect of separating the body of the soil into sections and horizons. Only the topsoil has been used to yield crops by these extraction fertility methods.

  Replenishment of the very small amount of minerals required from the subsoil has been rendered ineffective. Eventually this manifests itself in top soil and crop deficiencies no matter how fertile the soil originally. These soil deficiencies reach man and affect his health through impoverished foods.

  Plow soles or hard pans have been formed at the cultivation depth by implements that exert a positive pressure on the soil at this depth to enable them to operate effectively. Plow soles resist the penetration of moisture and air. Surface soil above these plow soles becomes waterlogged in wet seasons. Deeper soil and subsoil dies from asphyxiation.

  When this happens plant roots have nothing to gain by penetrating this dead soil. These are all vital factors in maintaining and building soil fertility.

  Vegetation is controlled by such soil turning implements by simply burying the vegetation in a sandwich. This layer of turned-under vegetation acts to separate the soil further. It may remain dry, resisting decay and. insulating the top soil from the deeper soil moisture, thus making crops more and more dependant on well-distributed rainfall. Partial crop failure becomes more common. Full decay and growth are both interrupted. A too fine surface working of such primary cultivation further reduces the effect of rainfall by self-sealing tendencies. This will retard the infiltration rate of rainfall to such an extent that water will often be eroding some of this soil before all of it is wet to a depth of three inches. Finely cultivated heavy clay soil will very quickly form a sealed surface .during heavy rains.

  If mouldboard plows are used for deeper cultivation total crop failures often result. By deeply burying the surface soil, the soil life is destroyed. Soil of poor structure and fertility is turned up to the surface. Considerable time is required to make it again productive.

  Surface chopping and slicing implements, if over-cultivation is avoided, are much less destructive to soil fertility. Good management and such implements can start a cycle of soil improvement. They do tend, however, to separate the soil into sections by their even bottom-depth cultivation, and the danger, already mentioned, of destroying the completeness of the soil is ever present.

  With all the other abundant ingredients of fertile soil, what depth of the land is available to the farmer to supply the very small amount of minerals necessary? It is certainly not the alleged six or nine inches of top soil, vast quantities of which have been removed by erosion. The depth of soil available to supply the small mineral requirements extends to at least the full depth penetrated by the roots of the large trees.

  The whole deep root system of trees, occupying as they do usually a much greater area below the ground than the trunk and branches above, are continuously bringing in all the necessary minerals to the trunk, branches and leaves.

  Some of these minerals gathered by the roots and contained in the ever-falling leaves, twigs and small branches are available continually to improve the soil. Trees are a part of the fertility of the soil. Some need to be "left", or grown in a logically planned manner, to serve the soil and protect the land.

  Originally, large areas of land when only partly cleared, maintained healthy stock. Now, some years after complete timber destruction, it is unable to support healthy growth without added trace elements such as copper, zinc, cobalt, etc. No doubt these were once supplied to the surface by the growth of timber as described.

  Deep-rooted plants and grasses will all root deeper if the soil is developed fully, and will bring minerals toward the surface.

  The importance of preserving this complete process to the full depth of the soil--which includes top, deep and subsoil--has generally been entirely overlooked. Implements that tend to separate the whole body of the soil into defined sections are destructive to soil fertility. The all-over, even-bottom depth cultivation, whether shallow or deeper, destroys this soil completeness.

  However, it takes an appreciable time to destroy fertile soil. By wrong cultivation methods, farmers have been able to produce vast quantities of grain for generations during the process of fertility extraction.

  Now this soil has lost its former structure and its capacity to absorb fertility. Its destruction is much more rapid. Usually only three inches or a little more of the earth was used, while the basic materials for the improvement of fertility existed both above and below in limitless quantities.

  There is a general belief that the supply of food will be--almost is--the limiting factor in the ultimate population of the earth. It is likely--because of the tremendous supply of food potential in and above the earth and oceans--that some factor, other than food supply will first impose the limit.

  There has been available sufficient knowledge of soil to produce small areas and amounts of highly fertile soil for a long time. What is of particular importance now, in the further development of agricultural Australia, is a means of inducing or producing fertile soil over large areas of land quickly and profitably. It is only necessary to maintain the soil in a condition to absorb all the vast fertility potential of the sun, air and rainfall. If the rainfall is absorbed into the earth, the store of minerals, chemicals and gases it carries always is filtered out of it and retained in the soil. While oxygen--and rainfall is practically a saturated solution of oxygen--is probably needed by our soils more than any fertiliser the farmer uses at present, there is a considerable variety of other fertility factors taken out of the air by rainfall. Some plants that actually grow without contact with the earth have been found to contain a comparatively large amount of element in their ash-element of the "trace" variety--which they must, somehow, extract from air and rainfall.