Doug sent this good piece which helps explain how we can keep from "
raping the land."
"
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 pulverizing, 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 moldboard 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."
We moldboard plowed once every five years mainly for a clean seedbed. When we started no-tilling in 1976, we learned how to let crop residue help control the weeds.
This is a long reading today but answers many of the questions raised in "raping the land." There is an exhaustive library for your
winter reading pleasure here. Chapter One of today's
excerpt starts here.
Happy Reading!
Ed Winkle
