Healthy soil and sustainable growing

["Tradingpost" <tradingpost@lobo.net>]

Food and Population
by Peter Goodchild   01 February 2010
http://www.culturechange.org/cms/index.php?option=com_content&task=view&id=600&Itemid=1

Farmers are invisible people, and middle-class city dwellers choose to 
pretend that the long lines of trucks bringing food into the city at dawn 
every day have nothing to do with the white-collar world. Perhaps it is a 
mark of the civilized person to believe that the essentials of food, 
clothing, and shelter have no relevance to daily life. Yet if the farmers 
stopped sending food into the great vacuum of the metropolis, the great maw 
of urbanity, the city would soon start to crumble, as Britain discovered in 
the year 2000 [5]. The next question, then, is: Where does all this food come 
from?

Is there such a thing as sustainable agriculture, or is “sustainable 
agriculture” a self-contradictory term? To keep a piece of land producing 
crops, it is necessary to maintain a high level of various minerals. The most 
critical are phosphorus (P), potassium (K), and especially nitrogen (N). 
These minerals might be abundant in the soil before any cultivation is done, 
but whenever crops are harvested a certain amount of the three critical 
elements is removed.

The native people of North America had a simple solution: abandonment [3]. No 
fertilizer was used, except for the ashes from burned undergrowth and corn 
stalks. As a result, the soil became exhausted after a few years, so the 
fields were abandoned and new ones were dug. Primitive agriculture in many 
other parts of the world has been similar, and sometimes such a technique is 
called “slash-and-burn.”

A common partial solution to the N-P-K problem, used in many countries for 
centuries, has been to turn crop waste into compost and put it back onto the 
land. The problem with that technique, however, is that one cannot create a 
perpetual-motion machine: every time the compost is recycled, a certain 
amount of N-P-K is lost, mainly in the form of human and animal excrement 
(after the crops are eaten) but also as direct leaching and evaporation. One 
can come closer to sustainability by recycling those human and animal wastes, 
but the recycling will always be less than perfect. After all, nitrogen, 
phosphorus, and potassium are elements, and by definition they cannot be 
created. Of the three elements, nitrogen is by far the most subject to loss 
by leaching, but to some extent that can also happen with phosphorus and 
potassium.

In the original organic-gardening movement pioneered by Sir Albert Howard in 
the early years of the twentieth century, nothing but vegetable compost and 
animal manure was allowed. In modern organic gardening, a common technique is 
to replace lost minerals by adding rock powders, particularly rock phosphate 
and granite dust. For most present-day gardeners and farmers, the usual 
response to the problem of soil replenishment is to apply artificial 
fertilizer, N-P-K largely derived from those same types of rock used in 
organic gardening. (In fact, the use of rock powders in later organic 
gardening sounds suspiciously like a drift toward artificial fertilizers.) 
When the fragile international networks of civilization break down, however, 
then neither rock powders nor artificial fertilizer will be readily 
available. These materials are very much the products of civilization, 
requiring a market system that ties together an entire country, or an entire 
world.

Writing early in the twentieth century [4], F.H. King claimed that farmers in 
China, Japan, and Korea were managing to grow abundant crops on about one 
tenth as much cultivable land per capita as Americans, and that they had done 
so for four thousand years. If they kept their land producing for 40 
centuries, what was their secret? The answer, in part, is that most of 
eastern Asia has an excellent climate, with rainfall most abundant when it is 
most needed. More importantly, agriculture was sustained by the practice of 
returning almost all waste to the soil — even human excrement from the cities 
was carried long distances to the farms. Various legumes, grown in the fields 
between the planting of food crops, fixed atmospheric nitrogen in the soil. 
Much of the annually depleted N-P-K, however, was replaced by taking 
vegetation from the hillsides and mountains, and by the use of silt, which 
was taken from the irrigation canals but which originated in the mountains. 
The system, therefore, was not a closed system, because it took materials 
from outside the farms.

These three countries are, in any case, problematic as sources of 
agricultural “wisdom.” King remarks that “the first days of travel in these 
old countries force the over-crowding upon the attention as nothing else 
can.” In a chapter on Tientsin, he cites a Scottish physician’s description 
of a common solution to over-crowding: “In times of famine the girls 
especially are disposed of, often permitted to die when very young for lack 
of care. Many are sold at such times to go into other provinces.” As for the 
hard labor and low remuneration, King says of a Japanese rice farmer that “it 
is difficult for Americans to understand how it is possible for the will of 
man, even when spurred by the love of home and family, to hold flesh to tasks 
like these.” The “miracle” of growing so much food on so little land was 
largely due, therefore, to neither technology nor topography, but to the fact 
that starvation was the only alternative.

Besides using vegetable compost and animal manure for increasing the 
sustainability of agricultural land, many societies have employed related 
techniques, such as crop-rotation, fallowing, cover-cropping, and green 
manuring. If any of these techniques includes the use of legumes, nitrogen is 
added to the soil. Such practices also replenish the humus content of the 
soil, important for retaining moisture and minerals.

In some societies, agriculture meant slow but inexorable burnout, as was the 
case for most of Europe. In other cultures (China, Japan, Korea etc.) the 
response was to recycle intensively. As much as possible, vegetable compost 
and human and animal excrement had to be reclaimed, and other loss was made 
up by importing soil and vegetation from the wilderness. Even for those 
cultures, however, a growing population exacerbated the problems.

Vernon Gill Carter and Tom Dale [2] claim that all previous civilizations 
have managed to destroy their agricultural systems, except for a few 
societies that were lucky enough to have sufficient annual flooding, thereby 
replenishing their soils from an outside source. The Egyptians long ago had 
such replenishment from the Nile, which brought a small but sufficient annual 
supply of silt from the highlands of Ethiopia and central Africa; it was 
Egyptian grain that kept the Roman Empire alive. The inhabitants of 
Mesopotamia received new silt annually from the Tigris and Euphrates. Carter 
and Dale regard the Indus Valley civilization as in a similar situation to 
that of Mesopotamia. Perhaps the situation of China, Korea, and especially 
Japan is similar to that of Egypt, since all three Asian countries (as 
described by King) used to derive much of their soil fertility from 
river-borne silt. In describing the Far East, however, Carter and Dale are 
generally closer to the mark than King. Speaking of China, they note that 
“erosion as a whole continues to ruin much of the land, reducing China, as a 
whole, to the status of a poor country with poor undernourished people, 
mainly because the land has been misused for so long.”

In the first chapter of Walden, Thoreau says that it would be better “to 
select a fresh spot from time to time than to manure the old.” Perhaps he was 
right. His method, which is essentially the type of practice referred to 
above as abandonment, might not be ecologically sound, since on a large scale 
it would mean leaving behind a long string of what used to be called 
“worked-out farms.” For a large population of farmers and consumers, such a 
method would be impractical, although many ancient cultures tried it. On a 
very small scale, however, it might not be so ecologically unsound, since the 
abandoned spot would, over many years, revert to reasonably fertile land, 
particularly if there were wild legumes to replace the nitrogen.

One further possible disadvantage to Thoreau’s suggestion is that preparing 
the “fresh spot” might require a good deal of work. It is noteworthy that the 
native North Americans preferred forest, rather than grassland, as sites for 
agriculture — the forest land was more fertile, and digging up heavy sod 
(especially on the prairies) would have been arduous with the available 
tools. The native people girdled the trees (cutting a ring of bark from 
around each tree) to kill them, and then felled the trees much later, with 
fire and axes.

Actually, if the abandoned land is taken up again at a later date, the 
practice of abandonment tends to fade into that of fallowing, another 
practice to be found in many societies. With the traditional European method 
of fallowing, half the land is left to revert to grass and weeds for a year 
before being plowed again. Alternately, a farmer’s land might be divided into 
three parts, and the fallow portion might be part of a system of crop 
rotation.

World agriculture faces the problem of a reduction in arable land, but there 
is also the problem of water. The natural availability of water has always 
been one of the most critical factors in farming. Nearly half of the United 
States receives only 20 inches or less rainfall annually. Low precipitation, 
however, is a problem on every continent. In a real survival situation, what 
are the chances that anyone would be able to pick up a plastic hose and get 
an endless supply of clear cold water? Not very great. Even wells, cisterns, 
and ponds would be useless if their water flow had been controlled by 
electricity. When water must be pumped by hand or carried in buckets, it 
becomes a precious commodity.

One possible response to aridity is dry farming, leaving crops at the mercy 
of the weather, relying solely on whatever rain may fall [4]. Grains, 
legumes, potatoes, and several other crops can be farmed in this way. “Dry 
farming” will again become a popular term, as the aquifers run out of water 
and modern systems of agriculture become largely impossible. The essence of 
dry farming is to space out plants so that the distance between them is two 
or three times greater than usual. The roots can thereby spread out in all 
directions, finding water that has been stored in the ground in previous 
months. Because each plant has more room in which to grow, reducing plant 
density does not lower the total yield by an equal amount. To make the best 
use of the water in the ground, all weeds must be removed, because most water 
vanishes by evaporating from the leaves of any plants that are growing on 
that soil. The ground must be hoed or otherwise cultivated frequently, so 
that the surface is kept watertight under a “dust mulch”: water does not 
easily pass through a layer of well-disturbed dust, since the lack of water 
and the separation of soil particles prevent capillary action [6]. Further 
conservation of soil moisture can be achieved by the use of windbreaks. Dry 
farming is an excellent means of producing food without dependence on complex 
technology. Dry farming, however, can only make better use of the world’s 
soil; it cannot increase the yield of the world’s crops.

But the world’s food problems cannot be solved merely by devising a method to 
increase agriculture. The world’s human population is now approaching 7 
billion, while the amount of arable land is not great. Massive inputs of 
artificial fertilizers and pesticides only replace one problem with others: 
poisoned water, eroded soil, and insufficient humus. Even the world’s present 
arable land is rapidly disappearing under cities and highways. Nor can we 
extend that land by pumping more water from underground, because the aquifers 
cannot be made to yield more water than they receive.

The real solutions bear little resemblance to anything that is intellectually 
fashionable. What is of primary importance is to discard the glib, facile 
sermons that are often tacked on: “We must do such-and-such” or “We have to 
do such-and-such.” After all, who is the “we” in these statements? If “we” 
means the poor and powerless, then the statements may be false, because often 
such people cannot force the political and economic elite to make massive 
changes in policy. If “we” means the rich and powerful, then the statements 
are even more likely to be false, because these people have only to say, “No, 
we don’t have to. We are in power, and no one can make us change — certainly 
not silly book-scribblers.”

There may be something resembling sustainability, depending partly on one’s 
definitions, but it would have little to do with the simplistic concepts that 
are usually put forward. In the first place, there is nothing “natural” about 
agriculture. Agriculture has only been practiced for about ten percent of the 
entire history of Homo sapiens, and in that sense it is still an experiment 
with uncertain results. To plow the earth is to “go against Nature,” since it 
means disturbing the soil, the intricate, complex surface of the planet. Even 
the slightest and shallowest disturbance causes chemical and biological 
losses of various sorts. Yet in some countries one can drive for days without 
seeing an end to cultivated land (or, of course, concrete and asphalt). 
Almost no attention is paid to the final consequences of such practices, and 
the relentless quest for money makes it unlikely that serious attention will 
ever be paid. Even on a theoretical level, the permanent feeding of humanity 
is not simple. Any long-term solution would require paying as much attention 
to restoration of the land as has previously been paid to its cultivation.

Secondly and more importantly, to maintain a permanent balance between 
population and cultivation would require a considerable reduction in the 
former. It is foolish to say that the gap between food and population can be 
met by increasing the production of food. The error, a rather obvious one, is 
that an increase in food is inevitably followed by a further increase in 
population, which in turn leads to another shortage of food. Since the dawn 
of the human race, people have been trying to find ways to increase the food 
supply; often they have succeeded. Perhaps the biggest success of all was 
agriculture itself, the discovery that one can deliberately put seeds into 
the ground and foster their growth, rather than going off into the jungle to 
look for plants growing in the wild. That particular revolution led to a 
great increase in human population. The original problem, however, simply 
recurred. The solution (some means of increasing food) always leads straight 
back to the original problem (an excess population).

But these two forces do not act merely in a circular fashion. It would be 
more exact to say that they act as an ever-widening spiral. If we double the 
food supply, and thereby induce a doubling of human population, the new 
problem (that of excessive population) is not entirely identical to the 
original problem, because as the spiral widens it creates further dangers.

At some point, we push the planet Earth to the point where it can no longer 
maintain that spiral. We can convert vast quantities of petrochemicals into 
fertilizers and pesticides, we can draw water out of the deepest aquifers and 
even desalinate the oceans, but at some point we have to face the fact that 
the Earth is only a small rock, small enough that it can be encircled by a 
jet plane in a matter of hours. We are squeezing both our residential areas 
and our farmlands beyond endurance. The greatest danger of such a spiral is 
that when it breaks, it will do so in a far more destructive way than if the 
problem had been solved earlier. When the human race suddenly finds itself 
unable to manage the reciprocity of overpopulation and food production, there 
will be no more choices left to make.

References

1. Brengle, K.G. Principles and Practices of Dryland Farming. Boulder, 
Colorado: Colorado Associated University Press, 1982.

2. Carter, Vernon Gill, and Tom Dale. Topsoil and Civilization. Rev. ed. 
Norman, Oklahoma: U of Oklahoma P, 1981.

3. Driver, Harold E. Indians of North America. 2nd ed. rev. Chicago: 
University of Chicago Press, 1961.

4. King, F.H. Farmers of Forty Centuries, or, Permanent Agriculture in China, 
Korea and Japan. Various editions.

5. McMahon, Kathy. “Remember, Remember the 5th of September, 2000.” Peak Oil 
Blues. www.peakoilblues.com

6. Solomon, Steve. Water-Wise Vegetables. Seattle: Sasquatch, 1993.


Peter Goodchild is the author of Survival Skills of the North American 
Indians, published by Chicago Review Press. His email address is odonatus 
[at] live.com.