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CHAPTER 2. POTENTIALLY ARABLE SOILS OF THE WORLD AND CRITICAL MEASURES FOR THEIR USE
CHARLES E. KELLOGG A N D ARNOLD C. ORVEDAL
efficient as those, say, in Holland, it would be easy. But most are not.
Building the necessary institutions for effective technical assistance requires time and patience. As pointed out by Broekmeijer (1966), we are
thinking in terms of centuries, not simply decades.
Much has been written recently about the world food problem, sometimes garnished with such catch phrases as “the race between food and
population” or “the oncoming famine.” Yet it is highly doubtful that food
situations in the 95 less developed countries are as bad now as they were
earlier. Most people in these countries formerly took famine, flood, and
pestilence for granted as man’s inevitable tragedies. Since 1940, world
communications have improved. Many people from advanced countries
have traveled in the less developed countries. In turn, people from the
less developed countries have visited the advanced countries. They now
know that floods, famine, and pestilence can be avoided.
Certainly most have food problems. With the wide introduction of
medicine and sanitation, many of the less developed countries have experienced great decreases in death rates with corresponding increases in
population. Bogue ( 1 967) points out that current evidence suggests that
the birth rate may be on the way down, especially in those countries
where individuals have some social security besides many sons.
Poor people in these countries hope for better standards of living,
including many of the conveniences developed by the advanced countries
only within this century. Yet they need to be reminded that each of the
advanced countries without exception got its start toward economic
development from a reasonably efficient agriculture. Although people in
the less developed countries want some of the new things, the great
majority of them do not want to become Englishmen, Frenchmen, or
Americans. Instead they want to develop their own culture in their own
way and fit the new ways into their culture. As pointed out by Martin
and Knapp (19671, economic planning must be done differently in different countries.
Based on our experience, it seems clear that one cannot discuss even
briefly suggestions for increased food production in one or more countries
without also relating the suggestions to general economic development,
better use of all resources, equitable distribution of the national product,
improved living standards, and local cultures.
Since much that has been learned about science and its application to
farming and to the other sectors of agriculture has come from western
Europe and the United States, difficult problems of communications arise
in giving people the benefit of this knowledge in terms they can use with
understanding. Change needs to start where the people are, with their
POTENTIALLY ARABLE SOILS OF THE WORLD
skills, their culture, and their hopes and aspirations. Not much in the way
of advanced techniques can be transferred, even if it were desirable to do
so, from farmers in the advanced countries to farmers in the less developed countries. Nor are any two of these countries facing exactly the
same problems. Nor do they have the same potentials. Nor are they at
similar stages of cultural and economic development.
In some of the less developed countries there are religious and social
ideas that conflict with science or with the technology based on science.
With great patience and tact ideas can be changed slowly without damage
to the cultural systems, but certainly few other changes should be even
attempted at the start.
The modern systems of agriculture contrast with most of those in the
less developed countries. In the advanced countries the proportion of
agricultural workers on farms has been declining at an accelerating rate
for many years. In the United States, for example, perhaps only about
one-fifth of the labor force in agriculture works on farms. The majority
of people working in agriculture live in towns and cities. They make
machines, chemicals, and other supplies for farmers; process, transport,
and market farm products; and perform research, educational, financial,
and other services for both the farming and industrial sectors of agriculture.
This highly complex system we call “modern agriculture” requires a
host of highly skilled workers, technicians, managers, and scientists to
keep it going. Such systems evolved in educated societies along with
scientific research and its application, educational institutes, and dynamic
governmental systems. Then too, the agricultural system evolved in close
association with many other production and service activities.
It should be evident that technical assistance to the less developed
countries requires highly trained people with deep knowledge in those
scientific disciplines essential to agriculture and enough knowledge of
the broad field to understand how the several parts fit together. Those
giving technical assistance must be able to diagnose problems and potentials in natural and cultural environments unlike their own. Most
improvements need to be invented on the spot to fit both the local kinds
of soil and the social environment. Scientists must be able to communicate with the governments and people of the countries they assist in terms
of the local cultural systems.
By three broad ways can the total amount of food, fiber, and other
agricultural products be increased:
1. By improving the management of the many kinds of soil already
being used for crops;
CHARLES E. KELLOGG A N D ARNOLD C. ORVEDAL
2. By developing and managing well potentially arable soils not now
used for crops; and
3. By reducing preventable losses of farm products between the fields
of the cultivators and the kitchens of the consumers. Such losses are less
in modern agricultural systems. They result from diseases, insects,
rodents, and poor harvesting methods on farms, and from inadequate
processing, storage, and transport.
Improvements along any of these lines or some combination of them
depend on parallel development of the industrial and service sectors of
agriculture, including adequate transport, advisory services, and the like.
The Principle of Interactions in Soil Use
The most important single principle for guiding improved farming and
agricultural development is the principle of interactions: Each practice or
each program within a system affects all other components of the system,
so that a proper combination gives a far greater result than the sum of the
several components considered singly (Kellogg, 1962a). The principle
of interactions has been cryptically defined as a peculiar kind of mathematics from which the whole is much greater than the sum of its parts.
In technical assistance for agricultural development, this principle
guides the process at several levels: (1) reliable interpretations of the
responses of a soil to alternative management systems from field study of
its characteristics; (2) working out the most effective combination of
practices for a system of managing each specific local kind of soil by
people of known skills and with the facilities to give optimum production
on a sustained basis; (3) fitting together a management scheme for a
whole farm or group of holdings having unlike kinds of soil and different
enterprises; (4)an effective balance of services needed for an existing or
potential farming community to be successful; ( 5 ) organizing common
services for two or more resource uses in the economic development of a
large area or region; and ( 6 ) a balance of emphasis between the many
aspects of a national plan or system for economic and agricultural
progress, considering the skills of citizens, patterns of resources, sources
of revenue, transport facilities, and the like.
A. IN THE FIELD
Each farmer makes his arable soil from either a natural soil or an old
arable soil. He may change it only a little or he may change it drastically
by reshaping the surface for water control, by adding fertilizers to correct
plant nutrient deficiencies, by adding other materials to correct acidity
or alkalinity or to improve the structure of the soil, or by tilling in depth.
POTENTIALLY ARABLE SOILS OF THE WORLD
Within his skills and with the facilities available to him, he tries to make
the soil as nearly ideal as practicable for the crops most likely to grow
well. Only a tiny fraction of the soils of the world produce well under
simple management that includes only clearing, plowing, seeding, and
harvesting. For most crops the farmer needs a stable soil that water, air,
and roots can penetrate deeply in order to have a large volume of soil
for storing water and plant nutrients and for releasing them to the roots
of the plants.
For each kind of soil, and the associated climate and length of day,
standards can be designed for the combinations of characteristics that
an arable soil should have for the most rewarding results. No soilmanagement practice or system is universally beneficial. A well-proved
system for one kind of soil may be harmful or perhaps wasteful on another
kind, even in an adjoining field.
Because the effect of any single soil characteristic depends on the host
of other characteristics in the combination that makes a soil of a certain
kind, we cannot make useful generalizations in terms of a single soil
characteristic or even of only three or four. Few useful statements about
soil management can be made about salty soils, hilly soils, clayey soils,
red soils, or the like.
Because of differences in clay minerals, some kinds of gently sloping
clayey soils are slowly permeable to water and have a high erosion
hazard under cultivation, whereas other kinds of clayey soils are so
permeable to water that crops can be grown without significant erosion
even on soils with 40 percent slope. (Fig. I).
Every productive hectare of arable soil in the world has at least four
basic conditions, appropriately related to one another and to the local
kind of soil. A balanced combination may have been arrived at over
years of trial-and-error or through planning with the aid of science. If
adequate practices for any one of the conditions are neglected, little can
be expected from the other practices. Some unique kinds of soil respond
well to only a very few combinations of practices; other kinds of soil
have a wider range of alternatives. The four basic conditions are:
1. The arable soil needs a balanced supply of plant nutrients for
acceptable yields. For the best results, at least some chemical fertilizers
are nearly always necessary to supplement the supply of one or more of
the many essential plant nutrients within the soils plus that contributed
by compost, manures, crop residues, and green manures. Thus the kinds
and amounts of fertilizers to use depend on the soil, other practices, and
expected costs and returns. Fertilizers are especially critical in areas of
high rainfall and leaching, all the way from the cool temperate regions
to the humid Tropics (lgnatieff and Page, 1958).