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How to Build Up and Maintain the Virgin Fertility of Our Soils
Creator
Date
1936
Subject
Excerpt
Origin of Scientific Agriculture
One is not only surprised but astonished to learn that less than a century and a half ago, agriculture was without a scientific working basis. Credit goes to the great German chemist, Justus von Liebig for starting this revolutionary movement. The following four laws which form the foundation of modern agricultural practice were fully established by Liebig and should be studied and mastered by everyone attempting to deal with the fertility of the soil:
1. A soil can be termed fertile only when it contains all the materials requisite or necessary for the nutrition of plants in the required quantity and in the proper form.
2. With every crop a portion of these ingredients are removed. A part of this portion is again added from the inexhaustible store of the atmosphere; another part is lost forever if not restored by man.
3. The fertility of the soil remains unchanged if all the ingredients of a crop are given back to the land. Such a restitution is effected by fertilizers.
4. The fertilizers produced in the course of husbandry are not sufficient to maintain permanently the fertility of a farm; they lack the constituents which are annually exported in the shape of grain, hay, milk, and live stock.
One is not only surprised but astonished to learn that less than a century and a half ago, agriculture was without a scientific working basis. Credit goes to the great German chemist, Justus von Liebig for starting this revolutionary movement. The following four laws which form the foundation of modern agricultural practice were fully established by Liebig and should be studied and mastered by everyone attempting to deal with the fertility of the soil:
1. A soil can be termed fertile only when it contains all the materials requisite or necessary for the nutrition of plants in the required quantity and in the proper form.
2. With every crop a portion of these ingredients are removed. A part of this portion is again added from the inexhaustible store of the atmosphere; another part is lost forever if not restored by man.
3. The fertility of the soil remains unchanged if all the ingredients of a crop are given back to the land. Such a restitution is effected by fertilizers.
4. The fertilizers produced in the course of husbandry are not sufficient to maintain permanently the fertility of a farm; they lack the constituents which are annually exported in the shape of grain, hay, milk, and live stock.
Title
How to Build Up and Maintain the Virgin Fertility of Our Soils