Text A. Agricultural operations

1. Soils are used in a great variety of ways, agriculture being the leading soil use.

There has always been great variation in the quality of soils available for agriculture. In most instances, the better soils are used for crops, and the less suitable ones are kept for pastures or timberlands.

2. Properties that determine the agricultural quality of soils include: 1) ability to produce high crop yields under good management and careful handling; 2) the ease with which they can be used profitably; 3) the amount and kind of care they require. Good soils respond well to proper management, which involves correct cropping practices, use of fertilizers, and effective protection against damage.

3. Land use is a continuous operation. Farmers normally do not put their land aside while they are restoring their soils; they repair and improve them while the land is in use. The ways that soils are used, the length of time they remain productive, and the harvests they yield depend to a marked degree upon the care they receive.

4. Time makes little change in virgin soils. But when soils are used for crops or pasture, the balance that nature has given them is upset in various ways and to varying degrees. Changes in the nature of soils cannot be avoided as they are put to diverse uses. These changes may result in improvement in productivity. Frequently, however, soil use results in soil damage and decreased yields. Thus careful treatment of soils in ways that will keep them productive through continuous use is the aim of every good agricultural programme.

5. The systematic alternating of crops from field to field is known as crop rotation, which is one of the methods of soil conservation. A good rotation system consists of adjusting the crop arrangement to the physical nature of the land and, in the same time, maintaining a balanced economic farming programme. Rotation implies the growing of more than one crop on a farm. In other words, rotation and diversification go hand in hand.

6. Improper use may result in the deterioration of soil structure; several things may contribute to this deterioration, including: plowing when soil is too wet; failure to return organic matter; unwise use or lack of lime; neglecting to rotate crops. An even more serious and widespread kind of soil damage is the loss of essential plant nutrients. This may result from continuous growing of the same crop and from failing to fertilize it properly. Still another serious cause of depletion in most soils is known to be the loss of organic matter.

7. Most kinds of soil damage are related to each other in many ways. For example, organic deficiency is definitely a factor in soil erosion and in structural breakdown as well as in the deficiency of plant nutrients. Consequently, understanding these relationships and properly evaluating them in a balanced farming programme make modern agriculture truly a scientific undertaking.

8. Under careful and proper use soils may continue indefinitely to produce good yields. It is improper use and lack of care that harm soils. Thus good care is of vital importance in prolonging the useful life of soils.

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