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Title: Farming and Gardening for Health or Disease
Author: Sir Albert Howard
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FARMING AND GARDENING FOR HEALTH OR DISEASE
by SIR ALBERT HOWARD C.I.E., M.A.
Honorary Fellow of the Imperial College of Science,
Formerly Director of the Institute of Plant Industry, Indore,
and Agricultural Adviser to States in Central India and Rajputana


'The civilized nations--Greece, Rome, England--have been sustained by
the primitive forests which anciently rotted where they stood. They
survive as long as the soil is not exhausted.'

--THOREAU, Walking and the Wild.


'The staple foods may not contain the same nutritive substances as in
former times. . . . Chemical fertilizers, by increasing the abundance of
the crops without replacing all the exhausted elements of the soil, have
indirectly contributed to change the nutritive value of cereal grains
and of vegetables. . . . Hygienists have not paid sufficient attention
to the genesis of diseases. Their studies of conditions of life and
diet, and of their effects on the physiological and mental state of
modern man, are superficial, incomplete, and of too short duration. They
have, thus, contributed to the weakening of our body and our soul.'

--ALEXIS CARREL, Man the Unknown.


The preservation of fertility is the first duty of all that live by the
land. . . . There is only one rule of good husbandry--leave the land far
better than you found it.'

--GEORGE HENDERSON, The Farming Ladder.



assisted by LOUISE E. HOWARD




PREFACE



The earth's green carpet is the sole source of the food consumed by
livestock and mankind. It also furnishes many of the raw materials
needed by our factories. The consequence of abusing one of our greatest
possessions is disease. This is the punishment meted out by Mother Earth
for adopting methods of agriculture which are not in accordance with
Nature's law of return. We can begin to reverse this adverse verdict and
transform disease into health by the proper use of the green carpet--by
the faithful return to the soil of all available vegetable, animal, and
human wastes.

The purpose of this book is threefold: to emphasize the importance of
solar energy and the vegetable kingdom in human affairs; to record my
own observations and reflections, which have accumulated during some
forty-five years, on the occurrence and prevention of disease; to
establish the thesis that most of this disease can be traced to an
impoverished soil, which then leads to imperfectly synthesized protein
in the green leaf and finally to the breakdown of those protective
arrangements which Nature has designed for us.

During the course of the campaign for the reform of agriculture, now in
active progress all over the world, I have not hesitated to question the
soundness of present-day agricultural teaching and research--due to
failure to realize that the problems of the farm and garden are
biological rather than chemical. It follows, therefore, that the
foundations on which the artificial manure and poison spray industries
are based are also unsound. As a result of this onslaught, what has been
described as the war in the soil has broken out in many countries and
continues to spread. The first of the great battles now being fought
began in South Africa some ten years ago and has ended in a clear-cut
victory for organic farming. In New Zealand the struggle closely follows
the course of the South African conflict. The contest in Great Britain
and the United States of America has only now emerged from the initial
phase of reconnaissance, in the course of which the manifold weaknesses
of the fortress to be stormed have been discovered and laid bare.

I am indebted to some hundreds of correspondents all over the world for
sending me reports of the observations, experiments, and results which
have followed the faithful adoption of Nature's great law of return.
Some of this information is embodied and acknowledged in the pages of
this book. A great deal still remains to be summarized and reduced to
order--a labour which I hope soon to begin. When it is completed, a vast
mass of material will be available which will confirm and extend what is
to be found in these pages. Meanwhile a portion of this evidence is
being recorded by Dr. Lionel J. Picton, O.B.E., in the News-Letter on
Compost issued three times a year by the County Palatine of Chester
Local Medical and Panel Committees at Holmes Chapel, Cheshire. By this
means the story begun in their Medical Testament of 1939 is being
continued and the pioneers of organic farming and gardening are kept in
touch with events.

The fourth chapter on 'The Maintenance of Soil Fertility in Great
Britain' is very largely based on the labours of a friend and former
colleague, the late Mr. George Clarke, C.I.E., who, a few days before
his untimely death in May 1944, sent me the results of his study of the
various authorities on the Saxon Conquest, the evolution of the manor,
the changes it underwent as the result of the Domesday Book, and the
enthronement of the Feudal System till the decay of the open-field
system and its replacement by enclosure.

The spectacular progress in organic farming and gardening which has
taken place in South Africa and Rhodesia during the last few years owes
much to the work of Captain Moubray, Mr. J. P. J. van Vuren, and Mr. G.
C. Dymond, who have very generously placed their results at my disposal.
Captain Moubray and Mr. van Vuren have contributed two valuable
appendices, while Mr. Dymond's pioneering work on virus disease in the
cane and on composting at the Springfield Sugar Estate in Natal has been
embodied in the text. For the details relating to the breakdown of the
cacao industry in Trinidad and on the Gold Coast and for a number of
other suggestions on African and West Indian agriculture I am indebted
to Dr. H. Martin Leake, formerly Principal of the Imperial College of
Tropical Agriculture, Trinidad. have been kept in constant touch with
the progress of organic farming and gardening in the United States of
America by Mr. J. I. Rodale of Emmaus, Pa., the editor of Organic
Gardening, who has started a movement in the New World which promises
soon to become an avalanche. Mr. Rodale was the prime mover in bringing
out the first American edition of An Agricultural Testament and is
responsible for the simultaneous publication of this present book in the
United States and of a special American issue of Lady Eve Balfour's
stimulating work--The Living Soil.

In India I have made full use of the experience of Colonel Sir Edward
Hearle Cole, C.B., C.M.G., on the Coleyana Estate in the Punjab, and of
Mr. E. F. Watson's work on the composting of water hyacinth at
Barrackpore. Messrs. Walter Duncan & Company have generously permitted
Mr. J. C. Watson to contribute an appendix on the remarkable results he
has obtained on the Gandrapara Tea Estate in North Bengal. In this fine
property India and the rest of the Empire possess a perfect example of
the way Nature's law of return should be obeyed and of what freshly
prepared humus by itself can achieve.

I owe much to a number of the active members of the New Zealand Compost
Club, and in particular to its former Honorary Secretary, Mr. T. W. M.
Ashby, who have kept me fully informed of the results obtained by this
vigorous association. The nutritional results obtained by Dr. G. B.
Chapman, the President, at the Mount Albert Grammar School, which show
how profoundly the fresh produce of fertile soil influences the health
of schoolboys, have been of the greatest use. In Eire the Rev. C. W.
Sowby, Warden of the College of St. Columba, Rathfarnham, Co. Dublin,
and the Rev. W. S. Airy, Head Master of St. Martin's School, Sidmouth,
have placed at my disposal the results of similar work at their
respective schools. These pioneering efforts are certain to be copied
and to be developed far and wide. Similar ideas are now being applied to
factory canteen meals in Great Britain with great success, as will be
evident from what Mr. George Wood has already accomplished at the
Co-operative Wholesale Society's bacon factory at Winsford in Cheshire.

For furnishing full details of a large-scale example of successful
mechanized organic farming in this country and of the great
possibilities of our almost unused downlands I owe much to Mr. Friend
Sykes. The story of Chantry, where the results of humus without any help
from artificial manures are written on the land itself, provides a
fitting conclusion to this volume.

In the heavy task of getting this book into its final shape I owe much
to the care and devotion of my private secretary, Miss Ellinor Kirkham.

A.H. 14 Liskeard Gardens,
Blackheath, London, S.E.3.





CONTENTS


PREFACE

Chapter I. INTRODUCTION: An Adventure in Research


PART I THE PART PLAYED BY SOIL FERTILITY IN AGRICULTURE

Chapter II. THE OPERATIONS OF NATURE: The Life of the Plant,
The Living Soil, The Significance of Humus, The Importance of Minerals,
Summary

Chapter III. SYSTEMS OP AGRICULTURE: Primitive Forms of Agriculture,
Shifting Cultivation, The Harnessing of the Nile, Staircase Cultivation,
The Agriculture of China, The Agriculture of Greece and Rome, Farming
in the Middle Ages

Chapter IV. THE MAINTENANCE OP SOIL FERTILITY IN GREAT BRITAIN: The Roman
Occupation, The Saxon Conquest, The Open-Field System, The Depreciation
of Soil Fertility, The Low Yield of Wheat, The Black Death, Enclosure,
The Industrial Revolution and Soil Fertility, The Great Depression of
1879, The Second World War

Chapter V. INDUSTRIALISM AND THE PROFIT MOTIVE: The Exploitation of Virgin
Soil, The Profit Motive, The Consequence of Soil Exploitation, The Easy
Transfer of Fertility, The Road Farming Has Travelled

Chapter VI. THE INTRUSION OF SCIENCE: The Origin of Artificial Manures,
The Advent of the Laboratory Hermit, The Unsoundness of Rothamsted,
Artificials during the Two World Wars, The Shortcomings of Present-day
Agricultural Research


PART II DISEASE IN PRESENT-DAY FARMING AND GARDENING

Chapter VII. SOME DISEASES OF THE SOIL: Soil Erosion, The Formation
of Alkali Land

Chapter VIII. THE DISEASES OF CROPS: Sugar Cane, Coffee, Tea, Cacao,
Cotton, Rice, Wheat, Vine, Fruit, Tobacco, Leguminous Crops, Potato, Some
Parasitic Flowering Plants

Chapter IX. DISEASE AND HEALTH IN LIVESTOCK: Foot-and-Mouth Disease, Soil
Fertility and Disease, Concentrates and Contagious Abortion, Selective
Feeding by Instinct, Herbs and Livestock, The Maintenance of Our Breeds
of Poultry

Chapter X. SOIL FERTILITY AND HUMAN HEALTH

Chapter XII. THE NATURE OF DISEASE


PART III THE PROBLEM OF MANURING

Chapter XII. ORIGINS AND SCOPE OF THE PROBLEM: The Phosphate Problem and
Its Solution, The Reform of the Manure Heap, Sheet-Composting and Nitrogen
Fixation, The Utilization of Town Wastes, Summary

Chapter XIII. THE INDORE PROCESS AND ITS RECEPTION BY THE FARMING
AND GARDENING WORLDS: Some Practical Points, The New Zealand Compost Box,
Mechanization, The Spread of the Indore Process in the Farming and
Plantation Worlds, South Africa, Rhodesia, Malaya, India, New Zealand,
The United States of America, Great Britain

Chapter XIV. THE RECEPTION OF THE INDORE PROCESS BY THE SCIENTISTS


PART IV CONCLUSIONS AND SUGGESTIONS

Chapter XV. A FINAL SURVEY

APPENDICES:

A. PROGRESS MADE ON A TEA ESTATE IN NORTH BENGAL
B. COMPOST MAKING IN RHODESIA
C. THE UTILIZATION OF MUNICIPAL WASTES IN SOUTH AFRICA
D. FARMING FOR PROFIT ON A 750-ACRE FARM IN WILTSHIRE WITH ORGANIC MANURES
   AS THE SOLE MEDIUM OF REFERTILIZATION





CHAPTER I



INTRODUCTION


AN ADVENTURE IN RESEARCH

My first post was a somewhat unusual one. It included the conventional
investigation of plant diseases, but combined these duties with work on
general agriculture; officially I was described as Mycologist and
Agricultural Lecturer to the Imperial Department of Agriculture for the
West Indies.

The headquarters of the department were at Barbados. While I was here
provided with a laboratory for investigating the fungous diseases of
crops (mycology) and was given special facilities for the study of the
sugar-cane, in the Windward and Leeward Islands my main work was much
more general--the delivery of lectures on agricultural science to groups
of schoolmasters to help them to take up nature study and to make the
fullest use of school gardens.

Looking back I can now see where the emphasis of my job rightly lay. In
Barbados I was a laboratory hermit, a specialist of specialists, intent
on learning more and more about less and less: but in my tours of the
various islands I was forced to forget my specialist studies and become
interested in the growing of crops, which in these districts were
principally cacao, arrowroot, ground nuts, sugar-cane, bananas, limes,
oranges, and nutmegs. This contact with the land itself and with the
practical men working on it laid the foundations of my knowledge of
tropical agriculture.

This dual experience had not long been mine before I became aware of one
disconcerting circumstance. I began to detect a fundamental weakness in
the organization of that research which constituted officially the more
important part of my work. I was an investigator of plant diseases, but
I had myself no crops on which I could try out the remedies I advocated:
I could not take my own advice before offering it to other people. It
was borne in on me that there was a wide chasm between science in the
laboratory and practice in the field, and I began to suspect that unless
this gap could be bridged no real progress could be made in the control
of plant diseases: research and practice would remain apart: mycological
work threatened to degenerate into little more than a convenient agency
by which--provided I issued a sufficient supply of learned reports
fortified by a judicious mixture of scientific jargon--practical
difficulties could be side-tracked.

Towards the end of 1902, therefore, I took steps which terminated my
appointment and gave me a fresh start. My next post was more
promising--that of Botanist to the South-Eastern Agricultural College at
Wye in Kent, where in addition to teaching I was placed in charge of the
experiments on the growing and drying of hops which had been started by
the former Principal, Mr. A. D. (later Sir Daniel) Hall. These
experiments brought me in contact with a number of the leading hop
growers, notably Mr. Walter (afterwards Sir Walter) Berry, Mr. Alfred
Amos, and Colonel Honyball--all of whom spared no pains in helping me to
understand the cultivation of this most interesting crop. I began to
raise new varieties of hops by hybridization and at once made a
significant practical discovery--the almost magical effect of
pollination in speeding up the growth and also in increasing the
resistance of the developing female flowers (the hops of commerce) to
green-fly and mildew (a fungous disease) which often did considerable
damage. The significant thing about this work was that I was meeting the
practical men on their own ground. Actually their practice--that of
eliminating the male plant altogether from their hop gardens--was a wide
departure from natural law. My suggestion amounted to a demand that
Nature be no longer defied. It was for this reason highly successful. By
restoring pollination the health, the rate of growth, and finally the
yield of hops were improved. Soon the growers all over the hop-growing
areas of England saw to it that their gardens were provided with male
hops, which liberated ample pollen just as it was needed.

This, my first piece of really successful work, was done during the
summer of 1904--five years after I began research. It was obtained by
happy chance and gave me a glimpse of the way Nature regulates her
kingdom: it also did much to strengthen my conviction that the most
promising method of dealing with plant diseases lay in prevention--by
tuning up agricultural practice. But to continue such work the
investigator would need land and hops of his own with complete freedom
to grow them in his own way. Such facilities were not available and did
not seem possible at Wye.

Then my chance came. Early in 1905 I was offered and accepted the post
of Economic Botanist at the Agricultural Research Institute about to be
founded by Lord Curzon, the then Viceroy of India, at Pusa in Bengal. On
arrival in India in May 1905 the new institute only existed on paper,
but an area of about seventy-five acres of land at one end of the Pusa
Estate had not yet been allocated. I secured it instantly and spent my
first five years in India learning how to grow the crops which it was my
duty to improve by modern plant-breeding methods.

It was a decided advantage that officially my work was now no longer
concerned merely with the narrow problem of disease My main duties at
Pusa were the improvement of crops and the production of new varieties.
Over a period of nineteen years (1905-24) my time was devoted to this
task, in the course of which many new types of wheat (including
rust-resistant varieties), of tobacco, gram, and linseed were isolated,
tested, and widely distributed.

In pursuance of the principle I had adopted of joining practice to my
theory, the first step was to grow the crops I had to improve. I
determined to do so in close conformity with local methods. Indian
agriculture can point to a history of many centuries: there are records
of the same rice fields being farmed in north-east India which go back
for hundreds of years. What could be more sensible than to watch and
learn from an experience which had passed so prolonged a test of time? I
therefore set myself to make a preliminary study of Indian agriculture
and speedily found my reward.

Now the crops grown by the cultivators in the neighbourhood of Pusa were
remarkably free from pests: such things as insecticides and fungicides
found no place in this ancient system of cultivation. This was a very
striking fact, and I decided to break new ground and try out an idea
which had first occurred to me in the West Indies and had forced itself
on my attention at Wye, namely, to observe what happened when insect and
fungous diseases were left alone and allowed to develop unchecked,
indirect methods only, such as improved cultivation and more efficient
varieties, being employed to prevent attacks.

In pursuit of this idea I found I could do no better than watch the
operations of the peasants as aforesaid and regard them and the pests
for the time being as my best instructors.

In order to give my crops every chance of being attacked by parasites
nothing was done in the way of direct prevention; no insecticides and
fungicides were used; no diseased material was ever destroyed. As my
understanding of Indian agriculture progressed and as my practice
improved, a marked diminution of disease in my crops occurred. At the
end of five years' tuition under my new professors--the peasants and the
pests--the attacks of insects and fungi on all crops whose root systems
suited the local soil conditions became negligible. By 1910 I had learnt
how to grow healthy crops, practically free from disease, without the
slightest help from mycologists, entomologists, bacteriologists,
agricultural chemists, statisticians, clearing-houses of information,
artificial manures, spraying machines, insecticides, fungicides,
germicides, and all the other expensive paraphernalia of the modern
experiment station.

This preliminary exploration of the ground suggested that the birthright
of every crop is health.

In the course of the cultivation of the seventy-five acres at my
disposal I had to make use of the ordinary power unit in Indian
agriculture, which is oxen. It occurred to me that the same practices
which had been so successful in the growing of my crops might be worth
while if applied to my animals. To carry out such an idea it was
necessary to have these work cattle under my own charge, to design their
accommodation, and to arrange for their feeding, hygiene, and
management. At first this was refused, but after persistent importunity
backed by the powerful support of the Member of the Viceroy's Council in
charge of Agriculture (the late Sir Robert Carlyle, K.C.S.I.), I was
allowed to have charge of six pairs of oxen. I had little to learn in
this matter, as I belong to an old agricultural family and was brought
up on a farm which had made for itself a local reputation in the
management of cattle. My work animals were most carefully selected and
everything was done to provide them with suitable housing and with fresh
green fodder, silage, and grain, all produced from fertile land. I was
naturally intensely interested in watching the reaction of these
well-chosen and well-fed oxen to diseases like rinderpest, septicaemia,
and foot-and-mouth disease which frequently devastated the countryside.
(These epidemics are the result of starvation, due to the intense
pressure of the bovine population on the limited food supply.) None of
my animals were segregated; none were inoculated; they frequently came
in contact with diseased stock. As my small farmyard at Pusa was only
separated by a low hedge from one of the large cattle-sheds on the Pusa
estate, in which outbreaks of foot-and-mouth disease often occurred, I
have several times seen my oxen rubbing noses with foot-and-mouth cases.
Nothing happened. The healthy, well-fed animals failed to react to this
disease exactly as suitable varieties of crops, when properly grown, did
to insect and fungous pests--no infection took place. These experiences
were afterwards repeated at Indore in Central India, but here I had
forty not twelve oxen. A more detailed account of the prevention and
cure of foot-and-mouth disease is given in a later chapter (p. 153).

These observations, important as they appeared both at the time and in
retrospect, were however only incidental to my main work which was, as
already stated, the improvement of the varieties of Indian crops,
especially wheat. It was in the testing of the new kinds, which in the
case of wheat soon began to spread over some millions of acres of India,
that there gradually emerged the principle of which my observations
about disease did but supply the first links in evidence: namely, that
the foundations of all good cultivation lie not so much in the plant as
in the soil itself: there is so intimate a connection between the state
of the soil, i.e. its fertility, and the growth and health of the plant
as to outweigh every other factor. Thus on the capital point of increase
of yield, if by improvement in selection and breeding my new special
varieties of wheat, etc., might be estimated to produce an increase of
10 to 15 per cent, such yields could at once be increased not by this
paltry margin, but doubled or even trebled, when the new variety was
grown in soil brought up to the highest state of fertility. My results
were afterwards amply confirmed by my colleague, the late Mr. George
Clarke, C.I.E., who, by building up the humus content of his experiment
station at Shahjahanpur in the United Provinces and by adopting simple
improvements in cultivation and green-manuring, was able to treble the
yields of sugar-cane and wheat.

Between the years 1911 and 1918 my experience was considerably enlarged
by the study of the problems underlying irrigation and fruit growing.
For this purpose I was provided with a small experimental farm on the
loess soils of the Quetta valley in Baluchistan where, till 1918, the
summer months were spent. After a supply of moisture had been provided
to supplement the scanty winter rainfall, the limiting factors in crop
production proved to be soil aeration and the humus content of the land.
Failure to maintain aeration was indicated by a disease of the soil
itself. The soil flora became anaerobic: alkali salts developed: the
land died. The tribesmen kept the alkali condition at bay in their fruit
orchards in a very suggestive manner--by means of the deep-rooting
system of lucerne combined with surface dressings of farmyard manure.
Moreover they invariably combined their fruit growing with mixed farming
and livestock. Nowhere, as in the West, did one find the whole farm
devoted to fruit with no provision for an adequate supply of animal
manure. This method of fruit growing was accompanied by an absence of
insect and fungoid diseases: spraying machines and poison sprays were
unheard of: artificial manures were never used. The local methods of
grape growing were also intensely interesting. To save the precious
irrigation water and as a protection from the hot, dry winds, the vines
were planted in narrow ditches dug on the slopes of the valley and were
always manured with farmyard manure. Irrigation water was led along the
ditches and the vines were supported by the steep sides of the trenches.
At first sight all the conditions for insect and fungous diseases seemed
to be provided, but the plants were remarkably healthy. I never found
even a trace of disease. The quality of the produce was excellent: the
varieties grown were those which had been in cultivation in Afghanistan
for centuries. No signs of running out were observed. Here were results
in disease resistance and in the stability of the variety in striking
contrast to those of western Europe, where disease is notorious, the use
of artificial manures and poison sprays is universal, and where the
running out of the variety is constantly taking place (see also p. 135).

These results and observations taken together and prolonged over a
period of nineteen years at length indicated what should be the right
method of approach to the work I was doing. Improvement of varieties,
increased yields, freedom from disease were not distinct problems, but
formed parts of one subject and, so to speak, were members one of
another, all arising out of the great linkage between the soil, the
plant, and the animal. The line of advance lay not in dealing with these
factors separately but together. If this were to be the path of progress
and if it was useless to proceed except on the basis of crops grown on
fertile land, then the first prerequisite for all subsequent work would
be just the bringing of the experiment station area to the highest state
of fertility and maintaining it in that condition.

This, however, opened up a further problem. The only manure at the
command of the Indian cultivator was farmyard manure. Farmyard manure
was therefore essential, but even on the experiment stations the supply
of this material was always insufficient. The problem was how to
increase it in a country where a good deal of the cattle-dung has to be
burnt for fuel. No lasting good could be achieved unless this problem
were overcome, for no results could be applied to the country at large.

The solution was suggested by the age-long practices of China, where a
system of utilizing farm wastes and turning them into humus had been
evolved which, if applied to India, would make every Indian holding
self-supporting as regards manure. This idea called for investigation.

I now came up against a very great difficulty. Such a problem did not
fall within my official sphere of work. It obviously necessitated a
great deal of chemical and agricultural investigation under my personal
control and complete freedom to study all aspects of the question. But
while my idea was taking shape, the organization of agricultural
research at Pusa had also developed. A series of watertight
compartments--plant breeding, mycology, entomology, bacteriology,
agricultural chemistry, and practical agriculture--had become firmly
established. Vested interests were created which regarded the
organization as more important than its purpose. There was no room in it
for a comprehensive study of soil fertility and its many implications by
one member of the staff with complete freedom of action. My proposals
involved 'overlapping', a defect which was anathema both to the official
mind (which controlled finance) and to a research institute subdivided
as Pusa always had been.

The obvious course was to leave the institute and to collect the funds
to found a new centre where I could follow the gleam unhampered and
undisturbed. After a delay of six precious years, 1918-24, the Indore
Institute of Plant Industry (at which cotton was the principal crop) was
founded, where I was provided with land, ample money, and complete
freedom. Now the fundamental factor underlying the problems of Indian
cotton was none other than the raising of soil fertility. I might
therefore kill two birds with one stone. I could solve the cotton
problem if I could increase the amount of farmyard manure for India as a
whole.

At Indore I had a considerably larger area at my disposal, namely, 300
acres. From the outset the principles which I had worked out at Pusa
were applied to cotton. The results were even better. The yield of
cotton was almost trebled and the whole experiment station area stood
out from the surrounding countryside by reason of the fine crops grown.
Moreover these crops were free from disease, with only two exceptions,
during the whole eight years of my work there, exceptions in themselves
highly significant. A small field of gram, which had become accidentally
waterlogged three months before the crop was sown, was, a month after
sowing, found to be heavily attacked by the gram caterpillar, the
infected areas corresponding with the waterlogged areas with great
exactness, while the rest of the plot remained unaffected: the
caterpillar did not spread, though nothing was done to check it. In the
second case a field of san hemp (Crotalaria juncea, L.), originally
intended for green-manuring, was allowed to flower for seed; after
flowering it was smothered in mildew and insect pests and no seed set.
Subsequent trials showed that this crop will set seed and be disease
free on black soils only if the land is previously well manured with
farmyard manure or compost.

These results were progressive confirmation of the principle I was
working out--the connection between land in good heart and disease-free
crops: they were proof that as soon as land drops below par, disease may
set in. The first case showed the supreme importance of keeping the
physical texture of the soil right, the second was an interesting
example of the refusal of Mother Earth to be overworked, of her
unbreakable rule to limit herself strictly to that volume of operations
for which she has sufficient reserves: flowers were formed, but seed
refused to set and the mildew and insects were called in to remove the
imperfect product.

These were the exceptions to prove the rule, for during the eight years
of my work at Indore it was assumed by me as a preliminary condition to
all experiments that my fields must be fertile. This was brought about
by supplying them with heavy dressings of compost made on a simple
development of the Chinese system. As I was now free, it was possible
for me to make these arrangements on a large scale, and in the course of
doing so it seemed well worth while to work out the theory that underlay
the empiric Chinese practice. A complete series of experiments and
investigations were carried out, establishing the main chemical,
physical, and biological processes which go to humus formation in the
making of compost. In this work I received valuable help from Mr. Y. D.
Wad who was in charge of the chemical side of the investigation. On my
retirement from official service in 1931 I assumed that the publication
of this joint work in book form would be the last scientific task which
I should ever undertake.

It proved instead to be the beginning of a new period which has been
based on the long preparation which preceded it: the years of work and
experiment carried out in the tropics had gradually but inevitably led
me up to the threshold of ideas which embrace and explain the facts and
the practices, the theory and also the failures, which had met me in the
course of these thirty-two years. Our book on The Waste Products of
Agriculture; Their Utilization as Humus, designed to be a practical
guide to assist the Indian cotton cultivators, evoked a much wider
interest. The so-called Indore Process of making compost was started at
a number of centres in other countries and interesting results began to
be reported, very much like what I had obtained at Indore.

Two years after publication, in February 1933, I saw the inception of a
compost-making scheme at Colonel Grogan's estate not far from Nairobi in
Kenya Colony. During this visit it first occurred to me gradually to
terminate all my other activities and to confine myself to encouraging
the pioneers engaged in agriculture all over the world to restore and
maintain the fertility of their land. This would involve a campaign to
be carried out single-handed at my own expense as no official funds
could be expected for a project such as mine. Even if I could have
obtained the means needed it would have been necessary to work with
research organizations I had long regarded not only as obsolete, but as
the perfect means of preventing progress. A soil fertility campaign
carried on by a retired official would also throw light on another
question, namely, the relative value of complete freedom and
independence in getting things done in farming, as compared with the
present cumbrous and expensive governmental organization.

By the end of 1933 matters had progressed far enough to introduce the
Indore Process to a wider public. This was done by means of two lectures
before the Royal Society of Arts in 1933 and 1935, some thousands of
extra copies of both of which were distributed all over the world, and
subsequent contributions to the Journal of that society, to a German
periodical--Der Tropenflanzer--and a Spanish review--the Revista del
Instituto de Defensa del Cafe of Costa Rica. The process became
generally known and was found to be a most advantageous proposition in
the big plantation industries--coffee, tea, sugar, maize, tobacco,
sisal, rice, and vine--yields and quality alike being notably improved.
I devoted my energies to advising and assisting those interested, and
during this period became greatly indebted to the tea industry for
material help and encouragement.

In 1937 results were reported in the case of tea which were difficult to
explain. Single light dressings of Indore compost improved the yield of
leaf and increased the resistance of the bush to insect attacks in a way
which much surpassed what was normally to be expected from a first
application. While considering these cases I happened to read an account
of Dr. Rayner's work on conifers at Wareham in Dorsetshire, where small
applications of humus had also produced spectacular results. Normally
humus is considered to act on the plant indirectly: the oxidation of the
substances composing it ultimately forming salts in the soil, which are
then absorbed by the root hairs in the usual processes of nutrition. Was
there here, however, something more than this, some direct action having
an immediate effect and one very powerful?

Such indeed has proved to be the case and the explanation can now be set
forth of the wonderful double process by which Nature causes the plant
to draw its nurture from the soil. The mechanism by which living fungous
threads (mycelium) invade the cells of the young roots and are gradually
digested by these is described in detail in a later chapter (p. 28). It
was this, the mycorrhizal association, which was the explanation of what
had happened to the conifers and the tea shrubs, both forest plants, a
form of vegetation in which this association of root and fungus has been
known for a long time. This direct method of feeding would account for
the results observed (p. 33).

A number of inquiries which I was now able to set on foot revealed the
existence of this natural feeding mechanism in plant after plant, where
it had hitherto neither been observed nor looked for, but only, be it
noted, where there was ample humus in the soil. Where humus was wanting,
the mechanism was either absent or ineffective: the plant was limited to
the nurture derived by absorption of the salts in the soil solution: it
could not draw on these rich living threads, abounding in protein.

The importance of the opening up of this aspect of plant nutrition was
quite obvious. Here at last was a full and sufficient explanation of the
facts governing the health of plants. From this point on evidence began
to accumulate to illumine the new path of inquiry, which in my opinion
is destined to lead us a very long way indeed. It was clear that the
doubling of the processes of plant nutrition was one of those reserve
devices on which rests the permanence and stability of Nature. Plants
deprived of the mycorrhizal association continue to exist, but they lose
both their power to resist shock and their capacity to reproduce
themselves. A new set of facts suddenly fell into place: the running out
of varieties, a marked phenomenon of modern agriculture, to answer which
new varieties of the important crops have constantly to be bred--hence
the modern plant breeding station--could without hesitation be
attributed to the continued impoverishment of modern soils owing to the
prolonged negligence of the Western farmer to feed his fields with
humus. By contrast the maintenance of century-old varieties in the East,
so old that in India they bear ancient Sanskrit names, was proof of the
unimpaired capacity of the plant to breed in those countries where humus
was abundantly supplied.

The mycorrhizal association may not prove to be the only path by which
the nitrogen complexes derived from the digestion of proteins reach the
sap. Humus also nourishes countless millions of bacteria whose dead
bodies leave specks of protein thickly strewn throughout the soil. But
these complex bodies are not permanent: they are reduced by other soil
organisms to simpler and simpler bodies which finally become mineralized
to form the salts taken up by the roots for use in the green leaves. May
not some of the very early stages in the oxidation of these specks of
protein be absorbed by the root hairs from the soil water? It would seem
so, because a few crops exist, like the tomato, which although reacting
to humus are not provided with the mycorrhizal association. This matter
is discussed in the next chapter (p. 28).

These results set up a whole train of thought. The problem of disease
and health took on a wider scope. In March 1939 new ground was broken.
The Local Medical and Panel Committees of Cheshire, summing up their
experience of the working of the National Health Insurance Act for over
a quarter of a century in the county, did not hesitate to link up their
judgment on the unsatisfactory state of health of the human population
under their care with the problem of nutrition, tracing the line of
fault right back to an impoverished soil and supporting their
contentions by reference to the ideas which I had for some time been
advocating. Their arguments were powerfully supported by the results
obtained at the Peckham Health Centre and by the work, already
published, of Sir Robert McCarrison, which latter told the story from
the other side of the world and from a precisely opposite angle--he was
able to instance an Eastern people, the Hunzas, who were the direct
embodiment of an ideal of health and whose food was derived from soil
kept in a state of the highest natural fertility.

By these contemporaneous pioneering efforts the way was blazed for
treating the whole problem of health in soil, plant, animal, and man as
one great subject, calling for a boldly revised point of view and
entirely fresh investigations.

By this time sufficient evidence had accumulated for setting out the
case for soil fertility in book form. This was published in June 1940 by
the Oxford University Press under the title of An Agricultural
Testament. This book, now in its fourth English and second American
edition, set forth the whole gamut of connected problems as far as can
at present be done--what wider revelations the future holds is not yet
fully disclosed. In it I summed up my life's work and advanced the
following views:

1. The birthright of all living things is health.

2. This law is true for soil, plant, animal, and man: the health of
these four is one connected chain.

3. Any weakness or defect in the health of any earlier link in the chain
is carried on to the next and succeeding links, until it reaches the
last, namely, man.

4. The widespread vegetable and animal pests and diseases, which are
such a bane to modern agriculture, are evidence of a great failure of
health in the second (plant) and third (animal) links of the chain.

5. The impaired health of human populations (the fourth link) in modern
civilized countries is a consequence of this failure in the second and
third links.

6. This general failure in the last three links is to be attributed to
failure in the first link, the soil: the undernourishment of the soil is
at the root of all. The failure to maintain a healthy agriculture has
largely cancelled out all the advantages we have gained from our
improvements in hygiene, in housing, and our medical discoveries.

7. To retrace our steps is not really difficult if once we set our minds
to the problem. We have to bear in mind Nature's dictates, and we must
conform to her imperious demand: (e) for the return of all wastes to the
land; (b) for the mixture of the animal and vegetable existence; (c) for
the maintaining of an adequate reserve system of feeding the plant, i.e.
we must not interrupt the mycorrhizal association. If we are willing so
far to conform to natural law, we shall rapidly reap our reward not only
in a flourishing agriculture, but in the immense asset of an abounding
health in ourselves and in our children's children.

These ideas, straightforward as they appear when set forth in the form
given above, conflict with a number of vested interests. It has been my
self-appointed task during the last few years of my life to join hands
with those who are convinced of their truth to fight the forces impeding
progress. So large has been the flow of evidence accumulating that in
1941 it was decided to publish a News-Letter on Compost, embodying the
most interesting of the facts and opinions reaching me or others in the
campaign. The News-Letter, which appears three times a year under the
aegis of the Cheshire Local Medical and Panel Committees, has grown from
eight to sixty-four pages and is daily gaining new readers.

The general thesis that no one generation has a right to exhaust the
soil from which humanity must draw its sustenance has received further
powerful support from religious bodies. The clearest short exposition of
this idea is contained in one of the five fundamental principles adopted
by the recent Malvern Conference of the Christian Churches held with the
support of the late Archbishop of Canterbury, Dr. Temple. It is as
follows: 'The resources of the earth should be used as God's gifts to
the whole human race and used with due consideration for the needs of
the present and future generations.'

Food is the chief necessity of life. The plans for social security which
are now being discussed merely guarantee to the population a share in a
variable and, in present circumstances, an uncertain quantity of food,
most of it of very doubtful quality. Real security against want and ill
health can only be assured by an abundant supply of fresh food properly
grown in soil in good heart. The first place in post-war plans of
reconstruction must be given to soil fertility in every part of the
world. The land of this country and the Colonial Empire, which is the
direct responsibility of Parliament, must be raised to a higher level of
productivity by a rational system of farming which puts a stop to the
exploitation of land for the purpose of profit and takes into account
the importance of humus in producing food of good quality. The
electorate alone has the power of enforcing this and to do so it must
first realize the full implications of the problem.

They and they alone possess the power to insist that every boy and every
girl shall enter into their birthright--health, and that efficiency,
well-being, and contentment which depend thereon. One of the objects of
this book is to show the man in the street how this England of ours can
be born again. He can help in this task, which depends at least as much
on the plain efforts of the plain man in his own farm, garden, or
allotment as on all the expensive paraphernalia, apparatus, and
elaboration of the modern scientist: more so in all probability,
inasmuch as one small example always outweighs a ton of theory. If this
sort of effort can be made and the main outline of the problems at stake
are grasped, nothing can stop an immense advance in the well-being of
this island. A healthy population will be no mean achievement, for our
greatest possession is ourselves.

The man in the street will have to do three things:

1. He must create in his own farm, garden, or allotment examples without
end of what a fertile soil can do.

2. He must insist that the public meals in which he is directly
interested, such as those served in boarding schools, in the canteens of
day schools and of factories, in popular restaurants and tea shops, and
at the seaside resorts at which he takes his holidays are composed of
the fresh produce of fertile soil.

3. He must use his vote to compel his various
representatives--municipal, county, and parliamentary--to see to it: (a)
that the soil of this island is made fertile and maintained in this
condition; (b) that the public health system of the future is based on
the fresh produce of land in good heart.

This introduction started with the training of an agricultural
investigator: it ends with the principles underlying the public health
system of to-morrow. It has, therefore, covered much ground in
describing what is nothing less than an adventure in scientific
research. One lesson must be stressed. The difficulties met with and
overcome in the official portion of this journey were not part of the
subject investigated. They were man made and created by the research
organization itself. More time and energy had to be expended in
side-tracking the lets and hindrances freely strewn along the road by
the various well-meaning agencies Which controlled discovery than in
conducting the investigations themselves. When the day of retirement
came, all these obstacles vanished and the delights of complete freedom
were enjoyed. Progress was instantly accelerated. Results were soon
obtained throughout the length and breadth of the English-speaking
world, which make crystal clear the great role which soil fertility must
play in the future of mankind.

The real Arsenal of Democracy is a fertile soil, the fresh produce of
which is the birthright of the nations.





PART I THE PART PLAYED BY SOIL FERTILITY IN AGRICULTURE




CHAPTER II



THE OPERATIONS OF NATURE


The introduction to this book describes an adventure in agricultural
research and records the conclusions reached. If the somewhat unorthodox
views set out are sound, they will not stand alone but will be supported
and confirmed in a number of directions--by the farming experience of
the past and above all by the way Nature, the supreme farmer, manages
her kingdom. In this chapter the manner in which she conducts her
various agricultural operations will be briefly reviewed. In surveying
the significant characteristics of the life--vegetable and animal--met
with in Nature particular attention will be paid to the importance of
fertility in the soil and to the occurrence and elimination of disease
in plants and animals.

What is the character of life on this planet? What are its great
qualities? The answer is simple. The outstanding characteristics of
Nature are variety and stability.

The variety of the natural life around us is such as to strike even the
child's imagination, who sees in the fields and copses near his home, in
the ponds and streams and seaside pools round which he plays, or, if
being city-born he be deprived of these delightful playgrounds, even in
his poor back-garden or in the neighbouring park, an infinite choice of
different flowers and plants and trees, coupled with an animal world
full of rich changes and surprises, in fact, a plenitude of the forms of
living things constituting the first and probably the most powerful
introduction he will ever receive into the nature of the universe of
which he is himself a part.

The infinite variety of forms visible to the naked eye is carried much
farther by the microscope. When, for example, the green slime in
stagnant water is examined, a new world is disclosed--a multitude of
simple flowerless plants--the blue-green and the green algae--always
accompanied by the lower forms of animal life. We shall see in a later
chapter (p. 126) that on the operations of these green algae the
well-being of the rice crop, which nourishes countless millions of the
human race, depends. If a fragment of mouldy bread is suitably
magnified, members of still another group of flowerless plants, made up
of fine, transparent threads entirely devoid of green colouring matter,
come into view. These belong to the fungi, a large section of the
vegetable kingdom, which are of supreme importance in farming and
gardening.

It needs a more refined perception to recognize throughout this
stupendous wealth of varying shapes and forms the principle of
stability. Yet this principle dominates. It dominates by means of an
ever-recurring cycle, a cycle which, repeating itself silently and
ceaselessly, ensures the continuation of living matter. This cycle is
constituted of the successive and repeated processes of birth, growth,
maturity, death, and decay.

An eastern religion calls this cycle the Wheel of Life and no better
name could be given to it. The revolutions of this Wheel never falter
and are perfect. Death supersedes life and life rises again from what is
dead and decayed.

Because we are ourselves alive we are much more conscious of the
processes of growth than we are of the processes involved in death and
decay. This is perfectly natural and justifiable. Indeed, it is a very
powerful instinct in us and a healthy one. Yet, if we are fully grown
human beings, our education should have developed in our minds so much
of knowledge and reflection as to enable us to grasp intelligently the
vast role played in the universe by the processes making up the other or
more hidden half of the Wheel. In this respect, however, our general
education in the past has been gravely defective partly because science
itself has so sadly misled us. Those branches of knowledge dealing with
the vegetable and animal kingdoms--botany and zoology--have confined
themselves almost entirely to a study of living things and have given
little or no attention to what happens to these units of the universe
when they die and to the way in which their waste products and remains
affect the general environment on which both the plant and animal world
depend. When science itself is unbalanced, how can we blame education
for omitting in her teaching one of the things that really matter

For though the phases which are preparatory to life are, as a rule, less
obvious than the phases associated with the moment of birth and the
periods of growth, they are not less important. If once we can grasp
this and think in terms of ever-repeated advance and recession,
recession and advance, we have a truer view of the universe than if we
define death merely as an ending of what has been alive.

Nature herself is never satisfied except by an even balancing of her
processes--growth and decay. It is precisely this even balancing which
gives her unchallengeable stability. That stability is rock-like.
Indeed, this figure of speech is a poor one, for the stability of Nature
is far more permanent than anything we can call a rock--rocks being
creations which themselves are subject to the great stream of
dissolution and rebirth, seeing that they suffer from weathering and are
formed again, that they can be changed into other substances and caught
up in the grand process of living: they too, as we shall see (p. 88),
are part of the Wheel of Life. However, we may at a first glance omit
the changes which affect the inert masses of this planet, petrological
and mineralogical: though very soon we shall realize how intimate is the
connection even between these and what is, in the common parlance,
alive. There is a direct bridge between things inorganic and things
organic and this too is part of the Wheel.

But before we start on our examination of that part of the great process
which now concerns us--namely, plant and animal life and the use man
makes of them--there is one further idea which we must master. It is
this. The stability of Nature is secured not only by means of a very
even balancing of her Wheel, by a perfect timing, so to say, of her
mechanisms, but also rests on a basis of enormous reserves. Nature is
never a hand-to-mouth practitioner. She is often called lavish and
wasteful, and at first sight one can be bewildered and astonished at the
apparent waste and extravagance which accompany the carrying on of
vegetable and animal existence. Yet a more exact examination shows her
working with an assured background of accumulated reserves, which are
stupendous and also essential. The least depletion in these reserves
induces vast changes and not until she has built them up again does she
resume the particular process on which she was engaged. A realization of
this principle of reserves is thus a further necessary item in a wide
view of natural law. Anyone who has recovered from a serious illness,
during which the human body lives partly on its own reserves, will
realize how Nature afterwards deals with such situations. During the
period of convalescence the patient appears to make little progress till
suddenly he resumes his old-time activities. During this waiting period
the reserves used up during illness are being replenished.


THE LIFE OF THE PLANT

A survey of the Wheel of Nature will best start from that rather rapid
series of processes which cause what we commonly call living matter to
come into active existence; that is, in fact, from the point where life
most obviously, to our eyes, begins. The section of the Wheel embracing
these processes is studied in physiology from the Greek, meaning to bring
to life, to grow.

But how does life begin on this planet? We can only say this: that the
prime agency in carrying it on is sunlight, because it is the source of
energy, and that the instrument for intercepting this energy and turning
it to account is the green leaf.

This wonderful little example of Nature's invention is a battery of
intricate mechanisms. Each cell in the interior of a green leaf contains
minute specks of a substance called chlorophyll and it is this
chlorophyll which enables the plant to grow. Growth implies a continuous
supply of nourishment. Now plants do not merely collect their food: they
manufacture it before they can feed. In this they differ from animals
and man, who search for what they can pass through their stomachs and
alimentary systems, but cannot do more; if they are unable to find what
is suitable to their natures and ready for them, they perish. A plant
is, in a way, a more wonderful instrument. It is an actual food factory,
making what it requires before it begins the processes of feeding and
digestion. The chlorophyll in the green leaf, with its capacity for
intercepting the energy of the sun, is the power unit that, so to say,
runs the machine. The green leaf enables the plant to draw simple raw
materials from diverse sources and to work them up into complex
combinations.

Thus from the air it absorbs carbon-dioxide (a compound of two parts of
oxygen to one of carbon), which is combined with more oxygen from the
atmosphere and with other substances, both living and inert, drawn from
the soil and from the water which permeates the soil. All these raw
materials are then assimilated in the plant and made into food. They
become organic compounds, i.e. compounds of carbon, classified
conveniently into groups known as carbohydrates, proteins, and fats;
together with an enormous volume of water (often over 90 per cent of the
whole plant) and interspersed with small quantities of chemical salts
which have not yet been converted into the organic phase, they make up
the whole structure of the plant--root, stem, leaf, flower, and seed.
This structure includes a big food reserve. The life principle, the
nature of which evades us and in all probability always will, resides in
the proteins looked at in the mass. These proteins carry on their work
in a cellulose framework made up of cells protected by an outer
integument and supported by a set of structures known as the vascular
bundles, which also conduct the sap from the roots to the leaves and
distribute the food manufactured there to the various centres of growth.
The whole of the plant structures are kept turgid by means of water.

The green leaf, with its chlorophyll battery, is therefore a perfectly
adapted agency for continuing life. It is, speaking plainly, the only
agency that can do this and is unique. Its efficiency is of supreme
importance. Because animals, including man, feed eventually on green
vegetation, either directly or through the bodies of other animals, it
is our sole final source of nutriment. There is no alternative supply.
Without sunlight and the capacity of the earth's green carpet to
intercept its energy for us, our industries, our trade, and our
possessions would soon be useless. It follows therefore that everything
on this planet must depend on the way mankind makes use of this green
carpet, in other words on its efficiency.

The green leaf does not, however, work by itself. It is only a part of
the plant. It is curious how easy it is to forget that normally we see
only one-half of each flowering plant, shrub, or tree: the rest is
buried in the ground. Yet the dying down of the visible growth of many
plants in the winter, their quick reappearance in the spring, should
teach us how essential and important a portion of all vegetation lives
out of our sight; it is evident that the root system, buried in the
ground, also holds the life of the plant in its grasp. It is therefore
not surprising to find that leaves and roots work together, forming a
partnership which must be put into fresh working order each season if
the plant is to live and grow,

If the function of the green leaf armed with its chlorophyll is to
manufacture the food the plant needs, the purpose of the roots is to
obtain the water and most of the raw materials required--the sap of the
plant being the medium by which these raw materials (collected from the
soil by the roots) are moved to the leaf. The work of the leaf we found
to be intricate: that of the roots is not less so. What is surprising is
to come upon two quite distinct ways in which the roots set about
collecting the materials which it is their business to supply to the
leaf; these two methods are carried on simultaneously. We can make a
very shrewd guess at the master principle which has put the second
method alongside the first: it is again the principle of providing a
reserve--this time of the vital proteins.

None of the materials that reach the green leaf by whatever method is
food: it is only the raw stuff from which food can be manufactured. By
the first method, which is the most obvious one, the root hairs search
out and pass into the transpiration current of the plant dissolved
substances which they find in the thin films of water spread between and
around each particle of earth; this film is known as the soil solution.
The substances dissolved in it include gases (mainly carbon dioxide and
oxygen) and a series of other substances known as chemical salts like
nitrates, compounds of potassium and phosphorus, and so forth, all
obtained by the breaking down of organic matter or from the destruction
of the mineral portions of the soil. In this breaking down of organic
matter we see in operation the reverse of the building-up process which
takes place in the leaf. Organic matter is continuously reverting to the
inorganic state: it becomes mineralized: nitrates are one form of the
outcome. It is the business of the root hairs to absorb these substances
from the soil solution and to pass them into the sap, so that the new
life-building process can start up again. In a soil in good heart the
soil solution will be well supplied with these salts. Incidentally we
may note that it has been the proved existence of these mineral chemical
constituents in the soil which, since the time of Liebig, has focused
attention on soil chemistry and has emphasized the passage of chemical
food materials from soil to plant to the neglect of other
considerations.

But the earth's green carpet is not confined to its remarkable power of
transforming the inert nitrates and mineral contents of the soil into an
active organic phase: it is utilized by Nature to establish for itself,
in addition, a direct connection, a kind of living bridge, between its
own life and the living portion of the soil. This is the second method
by which plants feed themselves. The importance of this process,
physiological in nature and not merely chemical, cannot be
over-emphasized and some description of it will now be attempted.


THE LIVING SOIL

The soil is, as a matter of fact, full of live organisms. It is
essential to conceive of it as something pulsating with life, not as a
dead or inert mass. There could be no greater misconception than to
regard the earth as dead: a handful of soil is teeming with life. The
living fungi, bacteria, and protozoa, invisibly present in the soil
complex, are known as the soil population. This population of millions
and millions of minute existences, quite invisible to our eyes of
course, pursue their own lives. They come into being, grow, work, and
die: they sometimes fight each other, win victories, or perish; for they
are divided into groups and families fitted to exist under all sorts of
conditions. The state of a soil will change with the victories won or
the losses sustained, and in one or other soil, or at one or other
moment, different groups will predominate.

This lively and exciting life of the soil is the first thing that sets
in motion the great Wheel of Life. Not without truth have poets and
priests paid worship to 'Mother Earth', the source of our being. What
poetry or religion have vaguely celebrated, science has minutely
examined, and very complete descriptions now exist of the character and
nature of the soil population, the various species of which have been
classified, labelled, and carefully observed. It is this life which is
continually being passed into the plant.

The process can actually be followed under the microscope. Some of the
individuals belonging to one of the most important groups in this mixed
population--the soil fungi--can be seen functioning. If we arrange a
vertical darkened glass window on the side of a deep pit in an orchard,
it is not difficult to see with the help of a good lens or a low-power
horizontal microscope (arranged to travel up and down a vertical fixed
rod) some of these soil fungi at work. They are visible in the
interstices of the soil as glistening white branching threads,
reminiscent of cobwebs. In Dr. Rogers's interesting experiments on the
root systems of fruit trees at East Malling Research Station, where this
method of observing them was initiated and demonstrated to me, these
fungous threads could be seen approaching the young apple roots in the
absorbing region (just behind the advancing root tips) on which the root
hairs are to be found. Dr. Rogers very kindly presented me with two
excellent photographs--one showing the general arrangement of his
observation chamber (Plate I), the other, taken on 6th July 1933, of a
root tip (magnified by about twelve) of Lane's Prince Albert (grafted on
root stock XVI) at sixteen inches below the surface, showing abundant
fungous strands running in the soil and coming into direct contact with
the growing root (Plate II).


PLATE I. OBSERVATION CHAMBER FOR ROOT STUDIES AT EAST MALLING


But this is only the beginning of the story. When a suitable section of
one of these young apple roots, growing in fertile soil and bearing
active root hairs, is examined, it will be found that these fine fungous
threads actually invade the cells of the root, where they can easily be
observed passing from one cell to another. But they do not remain there
very long. After a time the apple roots absorb these threads. All stages
of the actual digestion can be seen.

The significance of this process needs no argument. Here we have a
simple arrangement on the part of Nature by which the soil material on
which these fungi feed can be joined up, as it were, with the sap of the
tree. These fungous threads are very rich in protein and may contain as
much as 10 per cent of organic nitrogen; this protein is easily digested
by the ferments (enzymes) in the cells of the root; the resulting
nitrogen complexes, which are readily soluble, are then passed into the
sap current and so into the green leaf. An easy passage, as it were, has
been provided for food material to move from soil to plant in the form
of proteins and their digestion products, which latter in due course
reach the green leaf. The marriage of a fertile soil and the tree it
nourishes is thus arranged. Science calls these fungous threads mycelium
(again from a Greek word, xxxxx ), and as the Greek for root is xxx
(rhiza, cf. rhizome), the whole process is known as the mycorrhizal
association.

The reader who wishes to delve into the technical details relating to
the mycorrhizal association and its bearing on forestry and agriculture
should consult the following works:--

1. Rayner, M. C. and Neilson-Jones, W.--Problems in Tree Nutrition,
Faber & Faber, London, 1944.

2. Balfour, Lady Eve--The Living Soil, Faber & Faber, London, 1944.

3. Howard, Sir Albert--An Agricultural Testament, Oxford Press, 1940.

What is urgently needed at the moment is an account in simple,
non-technical language, of this remarkable link between a fertile soil
and the roots of the vast majority of flowering plants and its
significance in nutrition and disease resistance.


PLATE II. THE BEGINNINGS OF MYCORRHIZAL ASSOCIATION IN THE APPLE
Root-tip (x 12) of Lane's Prince Albert on root-stock M XVI at sixteen
inches below the surface, showing root-cap (A), young root hairs (C),
and older root hairs with drops of exudate (Cl). The cobweb-like
mycelial strands are well seen approaching the rootlet in the region
marked (C).


This partnership is universal in the forest and is general throughout
the vegetable kingdom. A few exceptions, however, exist which will be
referred to in the next paragraph.

Among the plants in which this mycorrhizal association has hitherto not
been observed are the tomato and certain cultivated members of the
cabbage family, many of which possess a very diffuse root system and
exceptionally elongated root hairs. Nevertheless, all these examples
respond very markedly to the condition of the soil in which they are
grown and if fed with dressings of humus will prosper. The question
naturally arises: Exactly how does this take place? What is the
alternative mechanism that replaces the absent mycorrhizal association?

A simple explanation would appear to be this. Fertile soils invariably
contain a greatly enhanced bacterial population whose dead remains must
be profusely scattered in the water films which bathe the compound soil
particles and the root hairs of the crops themselves; these specks of
dead organic matter, rich in protein, are finally mineralized into
simple salts like nitrates. We have already mentioned this breaking-down
process of the soil population. What is here to be noted is that it is
no sudden transformation, but takes place in stages. May not, therefore,
some at least of the first-formed nitrogen complexes, which result from
this breaking down, be absorbed by the root hairs and so added to the
sap current? That is to say that the non-mycorrhiza-forming plants, not
drawing on the soil fungi, do compensate themselves by absorbing organic
nitrogen in this form--they catch the bacterial soil population, as it
were, before it has been reduced to an entirely inert phase and so have
their link also with the biological life of the soil. That there must be
some such passage of matter on a biological basis is suggested by the
fact that only in fertile soil, i.e. in soils teeming with bacteria, do
these non-mycorrhiza formers reveal resistance to disease and high
quality in the produce, which means that only in these soils are they
really properly fed.

This would be a third method used by plants for feeding themselves, a
sort of half-way method between the absorption powers exercised by the
root hairs and the direct digestive capacity of the roots: as the
mechanism used in this method is presumably the root hairs, the
diffuseness of the root system of plants of the cabbage family would be
explained. It is possible that even mycorrhiza formers use this
alternative passage for organic nitrogen. There seems no reason at all
why this should not be so.

But how do the various agencies concerned in these intricate operations
manage to carry on their work, buried as they are away from the light
and thus unable to derive anything from the source of energy, the sun?
How do they do their initial work at all until they can hand over to the
green leaf? They derive their energy by oxidising (i.e. burning up) the
stores of organic matter in the soil. As in an ordinary fire, this
process of oxidation releases energy. The oxygen needed for this slow
combustion is drawn from the air, in part washed down by the rain, which
dissolves it from the atmosphere in its descent. Incidentally this
explains why rain is so superior as a moistening agency for plants to
any form of watering from a can: incidentally, again, we can understand
the need for cultivating the soil and keeping it open, so that the
drawing in of oxygen, or the respiration of the soil, can proceed and
the excess carbon dioxide can be expelled into the atmosphere.

Humus is the Latin word for soil or earth. But as used by the husbandman
humus nowadays does not mean just earth in general, but indicates that
undecayed residue of vegetable and animal waste lying on the surface,
combined with the dead bodies of these bacteria and fungi themselves
when they have done their work, the whole being a highly complex and
somewhat varying substance which is, so to say, the mine or store or
bank from which the organisms of the soil and then, in direct
succession, the plant, the tree, and thereafter the animal draw what
they need for their existence. This store is all important.


THE SIGNIFICANCE OF HUMUS

Humus is the most significant of all Nature's reserves and as such
deserves a detailed examination.

A very perfect example of the methods by which Nature makes humus and
thus initiates the turning of her Wheel is afforded by the floor of the
forest. Dig down idly with a stick under any forest tree: first there
will be a rich, loose, accumulation of litter made up of dead leaves,
flowers, twigs, fragments of bark, bits of decaying wood, and so forth,
passing gradually as the material becomes more tightly packed into rich,
moist, sweet-smelling earth, which continues downwards for some inches
and which, when disturbed, reveals many forms of tiny insect and animal
life. We have been given here a glimpse of the way Nature makes
humus--the source from which the trunk of the tree has drawn its
resisting strength, its leaves their glittering beauty.

Throughout the year, endlessly and continuously, though faster at some
seasons than at others, the wastes of the forest thus accumulate and at
once undergo transformation. These wastes are of many kinds and mix as
they fall; for leaf mingles with twig and stem, flower with moss, and
bark with seed-coats. Moreover, vegetable mingles with animal. Let us
beware of the false idea that the forest is a part of the vegetable
kingdom only. Millions of animal existences are housed in it; mammals
and birds are everywhere and can be seen with the naked eye. The lower
forms of animal life--the invertebrates--are even more numerous.
Insects, earthworms, and so forth are obvious: the microscope reveals
new worlds of animal life down to simple protozoa. The excrete of these
animals while living and their dead bodies constitute an important
component of what lies on the forest floor; even the bodies of insects
form in the mass a constituent element not without importance, so that
in the end the two sources of waste are completely represented and are,
above all, completely mingled. But the volume of the vegetable wastes is
several times greater than that of the animal residues.

These wastes lie gently, only disturbed by wind or by the foot of a
passing animal. The top layer is thus very loose; ample air circulates
for several inches downwards: the conditions for the fermentation by the
moulds and microbes (which feed on the litter) are, as the scientist
would say, aerobic. But partly by pressure from above and partly as the
result of fermentation the lower layers are forced to pack more closely
and the final manufacture of humus goes on without much air: the
conditions are now anaerobic. This is a succession of two modes of
manufacture which we shall do well to remember, as in our practical work
it has to be imitated (p. 198).

This mass of accumulated wastes is acted on by the sunlight and the
rain; both are dispersed and fragmented by the leaf canopy of the trees
and undergrowth. The sunlight warms the litter; the rain keeps it moist.
The rain does not reach the litter as a driving sheet, but is split up
into small drops the impetus of whose fall is well broken. Nor does the
sunlight burn without shade; it is tempered. Finally, though air
circulates freely, there is perfect protection from the cooling and
drying effects of strong wind.

With abundant air, warmth, and water at their disposal the fungi and
bacteria, with which, as we have already noted, the soil is teeming, do
their work. The fallen mixed wastes are broken up; some passes through
the bodies of earthworms and insects: all is imperceptibly crumbled and
changed until it decomposes into that rich mass of dark colour and
earthy smell which is so characteristic of the forest 'door and which
holds such a wealth of potential plant nourishment.

The process that takes place in a prairie, a meadow, or a steppe is
similar; perhaps slower, and the richness of the layer of humus will
depend on a good many factors. One, in particular, has an obvious
effect, namely, the supply of air. If, for some reason, this is cut off,
the formation of humus is greatly impeded. Areas, therefore, that are
partly or completely waterlogged will not form humus as the forest does:
the upper portion of the soil will not have access to sufficient free
oxygen, nor will there be much oxygen in the standing water. In the
first case a moor will result; in the second a bog or morass will be
formed. In both these the conditions are anaerobic: the organisms derive
their oxygen not from the air but from the vegetable and animal residues
including the proteins. In this fermentation nitrogen is always lost and
the resulting low-quality humus is known as peat.

But the forest, the prairie, the moor, and the bog are not the only
areas where humus formation is in progress. It is constantly going on in
the most unlikely places--on exposed rock surfaces, on old walls, on the
trunks and branches of trees, and indeed wherever the lower forms of
plant life--algae, lichens, mosses, and liverworts--can live and then
slowly build up a small store of humus.

Nature, in fact, conforming to that principle of reserves, does not
attempt to create the higher forms of plant life until she has secured a
good store of humus. Watch how the small bits of decayed vegetation fall
into some crack in the rock and decompose: here is the little fern, the
tiny flower, secure of its supply of food and well able to look after
itself, as it thrusts its roots down into the rich pocket of
nourishment. Nature adapts her flora very carefully to her varying
supplies of humus. The plant above is the indicator of what the soil
below is like, and a trained observer, sweeping his eye over the
countryside, will be able to read it like the pages of a book and to
tell without troubling to cross a valley exactly where the ground is
waterlogged, where it is accumulating humus, where it is being eroded.
He looks at the kind and type of plant, and infers from their species
and condition the nature of the soil which they at once cover and
reveal.

But we are not at the end of the mechanisms employed by Nature to get
her great Wheel to revolve with smooth efficiency. The humus that lies
on the surface must be distributed and made accessible to the roots of
plants and especially to the absorbing portions of the roots and their
tiny prolongations known as root hairs--for it is these which do the
delicate work of absorption. How can this be done? Nature has, perforce,
laid her accumulation on the surface of the soil. But she has no fork or
spade: she cannot dig a trench and lay the food materials at the bottom
where the plant root can strike down and get them. It seems an impasse,
but the solution is again curiously simple and complete. Nature has her
own labour force--ants, termites, and above all earthworms. These carry
the humus down to the required deeper levels where the thrusting roots
can have access to it. This distribution process goes on continually,
varying in intensity with night and day, with wetness or dryness, heat
or cold, which alternately brings the worms to the surface for fresh
supplies or sends them down many feet. It is interesting to note how a
little heap of leaves in the garden disappears in the course of a night
or two when the earthworms are actively at work. The mechanism of humus
distribution is a give and take, for where a root has died the earthworm
or the termite will often follow the minute channel thus created a long
way.

Actually the earthworm eats of the humus and of the soil and passes them
through its body, leaving behind the casts which are really enriched
earth--perfectly conditioned for the use of plants. Analyses of these
casts show that they are some 40 per cent richer in humus than the
surface soil, but very much richer in such essential food materials as
combined nitrogen, phosphate, and potash. Recent results obtained by
Lunt and Jacobson of the Connecticut Experiment Station show that the
casts of earthworms are five times richer in combined nitrogen, seven
times richer in available phosphate, and eleven times richer in potash
than the upper six inches of soil.

It is estimated that on each acre of fertile land no less than
twenty-five tons of fresh worm casts are deposited each year. Besides
this the dead bodies of the earthworms must make an appreciable
contribution to the supply of manure. In these ways Nature in her
farming has arranged that the earth itself shall be her manure factory.

As the humus is continually being created, so it is continually being
used up. Not more than a certain depth accumulates on the surface,
normally anything from a few inches to two or three feet. For after a
time the process ceases to be additive and becomes simply continuous:
the growing plants use up the product at a rate equalling the rate of
manufacture--the even turning of the Wheel of Life--the perfect example
of balanced manuring. A reserve, however, is at all times present, and
on virgin and undisturbed land it may be very great indeed. This is an
important asset in man's husbandry; we shall later see how important.


THE IMPORTANCE OF MINERALS

Is the humus the only source from which the plant draws its nourishment?
That is not so. The subsoil, i.e. that part of the soil derived from the
decay of rocks, which lies below the layer of humus, also has its part
to play. The subsoil is, as it were, a depository of raw material. It
may be of many types, clay, sand, etc.; the geological formation will
vary widely. It always includes a mineral content--potash, phosphates,
and many rarer elements.

Now these minerals play an important part in the life of living things
They have to be conveyed to us in our food in an organic form, and it is
from the plant, which transforms them into an organic phase and holds
them thus, that we and the other animals derive them for our well-being.

How does the plant obtain them? We have seen that there is a power in
the roots of all plants, even the tiniest, of absorbing them from the
soil solution. But how is the soil solution itself impregnated with
these substances? Mainly through the dissolving power of the soil water,
which contains carbon dioxide in solution and so acts as a weak solvent.
It would appear that the roots of trees, which thrust down into the
subsoil, draw on the dissolved mineral wealth there stored and absorb
this wealth into their structure. In tapping the lower levels of water
present in the subsoil--for trees are like great pumps drawing at a deep
well--they also tap the minerals dissolved therein. These minerals are
then passed into all parts of the tree, including the foliage. When in
the autumn the foliage decays and falls, the stored minerals, now in an
organic phase, are dropped too and become available on the top layers of
the soil: they become incorporated in the humus. This explains the
importance of the leaf-fall in preserving the land in good heart and
incidentally is one reason why gardeners love to accumulate leaf-mould.
By this means they feed their vegetables, fruit, and flowers with the
minerals they need.

The tree has acted as a great circulatory system, and its importance in
this direction is to be stressed. The destruction of trees and forests
is therefore most injurious to the land, for not only are the physical
effects harmful--the anchoring roots and the sheltering leaf canopy
being alike removed--but the necessary circulation of minerals is put
out of action. It is at least possible that the present mineral poverty
of certain tracts of the earth's surface, e.g. on the South African
veldt, is due to the destruction over wide areas and for long periods of
all forest growth, both by the wasteful practices of indigenous tribes
and latterly sometimes by exploiting Western interests.


SUMMARY

Before we turn to consider the ways in which man has delved and dug
into all these riches and disturbed them for his own benefit, let us sum
up with one final glance at the operations of Nature. Perhaps one fact
will strike us as symptomatic of what we have been reviewing, namely,
the enormous care bestowed by Nature on the processes both of
destruction and of storage. She is as minute and careful, as generous in
her intentions, and as lavish in breaking down what she has created as
she was originally in building it up. The subsoil is called upon for
some of its water and minerals, the leaf has to decay and fall, the twig
is snapped by the wind, the very stem of the tree must break, lie, and
gradually be eaten away by minute vegetable or animal agents; these in
turn die, their bodies are acted on by quite invisible fungi and
bacteria; these also die, they are added to all the other wastes, and
the earthworm or ant begins to carry this accumulated reserve of all
earthly decay away. This accumulated reserve--humus--is the very
beginning of vegetable life and therefore of animal life and of our own
being. Such care, such intricate arrangements are surely worth studying,
as they are the basis of all Nature's farming and can be summed up in a
phrase--the Law of Return.

We have thus seen that one of the outstanding features of Nature's
farming is the care devoted to the manufacture of humus and to the
building up of a reserve. What does she do to control such things as
insect, fungous, and virus diseases in plants and the various
afflictions of her animal kingdom? What provision is to be found for
plans protection or for checking the diseases of animals? How is the
work of mycologists, entomologists, and veterinarians done by Mother
Earth? Is there any special method of dealing with diseased material
such as destruction by fire? For many years I have diligently searched
for some answer to these questions, or for some light on these matters.
My quest has produced only negative evidence. There appears to be no
special natural provision for controlling pests, for the destruction of
diseased material, or for protecting plants and animals against
infection. All manner of pests and diseases can be found here and there
in any wood or forest; the disease-infected wastes find their way into
the litter and are duly converted into humus. Methods designed for the
protection of plants and animals against infection do not appear to have
been provided. It would seem that the provision of humus is all that
Nature needs to protect her vegetation; and, nourished by the food thus
grown, in due course the animals look after themselves.

In their survey of world agriculture--past and present--the various
schools of agricultural science might be expected to include these
operations of Nature in their teaching. But when we examine the
syllabuses of these schools, we find hardly any references to this
subject and nothing whatever about the great Law of Return. The great
principle underlying Nature's farming has been ignored. Nay more, it has
been flouted and the cheapest method of transferring the reserves of
humus (left by the prairie and the forest) to the profit and loss
account of homo sapiens has been stressed instead. Surely there must be
something wrong somewhere with our agricultural education.




CHAPTER III



SYSTEMS OF AGRICULTURE


What is agriculture? It is undoubtedly the oldest of the great arts; its
beginnings are lost in the mists of man's earliest days. Moreover, it is
the foundation of settled life and therefore of all true civilization,
for until man had learnt to add the cultivation of plants to his
knowledge of hunting and fishing, he could not emerge from his savage
existence. This is no mere surmise: observation of surviving primitive
tribes, still in the hunting and fishing stage like the Bushmen and
Hottentots of Africa, show them unable to progress because they have not
mastered and developed the principle of cultivation of the soil.


PRIMITIVE FORMS OF AGRICULTURE

The earliest forms of agriculture were simple processes of gathering or
reaping. Man waited until Nature had perfected the fruits of the earth
and then seized them for his own use. It is to be noted that what is
intercepted is often some form of Nature's storage of reserves; more
especially are most ripe seeds the perfect arsenals of natural reserves.
Interception may, however, take other forms. A well-developed example of
human existence based on a technique of interception is the nomadic
pastoral tribe. Pastoral peoples are found all over the world; they have
played some part in the history of the human race and often exhibit an
advanced degree of culture in certain limited directions, not only
material. Their physical existence is sustained on what their flocks and
herds produce. To secure adequate grazing for their animals they wander,
sometimes to and fro between recognized summer and winter pastures,
sometimes over still greater distances. In this way they intercept the
fresh vegetable growths brought to birth season by season out of the
living earth; however successful, it is nothing more than a harvesting
process.

It is presumed rather than known that at some period man extended his
idea of harvesting to the gathering of the heads of certain plants, thus
adding a vegetable element to the milk, meat, and fish he had been
deriving from his animals and the chase. Wild barley, rice, and wheat
are all supposed to have been gathered in this way in different parts of
the earth. But real agriculture only began when, observing the
phenomenon of the germination of seeds, instead of consuming all that
they had gathered, men began to save some part of what they had in store
for sowing in the ground. This forced them to settlement, for they had
to wait until the plants grew from the seed and matured.

If at first the small store of gathered seed was sown in any bare and
handy patch, the convenience of clearing away forest growths so as to
extend the space for sowing soon became apparent. The next stage was to
prepare the ground thus won. The art of tillage has progressed over the
centuries. The use of a pointed stick drawn through the ground is still
quite common. The first ploughs were drawn by human labour--a practice
which survived even in such countries as Hungary and Romania into the
nineteenth century. But the use of animals, tamed for their muscular
strength to replace the human team, became the normal and world-wide
practice, until ousted in certain continents first by the still more
powerful steam engine and now by the internal combustion engine.

What was the purpose of this tillage, which is still the prime
agricultural process? The first effect is, of course, physical. The
loosened soil makes room for the seed, which thus can grow in abundance,
while to cover the sowing with scattered earth or to press it into the
ground protects it from the ravages of birds or insects. Secondly,
tillage gives access to the air--and the process of soil respiration
starts up, followed by the nitrification of organic matter and the
production of soluble nitrates. The rain, too, can penetrate better. In
this way physical, biological, and chemical effects are set in motion
and a series of lively physiological changes and transformations result
from the partnership between soil and plant. The soil produces food
materials: the plants begin to grow: the harvest is assured: the sowing
has become a crop.

Yet this is not the way in which Nature is accustomed to work. She does
not, as a rule, collect her plants, the same plants, in one spot and
practice monoculture, but scatters them: her mechanisms for scattering
seed are marvellous and most effective. Man's habit, so convenient, of
collecting a specified seed and sowing it in a specified area implies,
it must be acknowledged, a definite interference with Nature's habits.
Moreover, by consuming the harvest and thus removing it from the place
where it had grown he for the time being interrupts the round of natural
processes.

In fact, man has laid his hand on the great Wheel and for a moment has
stopped or deflected its turning. To put it in another way, he has for
his own use withdrawn from the soil the products of its fertility. That
man is entitled to put his hand on the Wheel has never been doubted,
except by such sects as the Doukhobors who argued themselves into a
state of declaring it a sin to wound the earth with spades or tools. But
if he is to continue to exist, he must send the Wheel forward again on
its revolutions. This is a necessary part of all primitive cultivation
practices and perhaps a tenet of all true early religions as soon as
they lift themselves from the stages of mere animism or fetish worship;
at any rate, all the great agricultural systems which have survived have
made it their business never to deplete the earth of its fertility
without at the same time beginning the process of restoration. This
becomes a veritable preoccupation.


SHIFTING CULTIVATION

The simplest way of doing this is after a time to leave the cultivated
patch and thus stop the process of interference. Nature will overrun it
again with scrub or forest: soon the green carpet is re-established: in
due course humus will accumulate: it will be as it was--the earth's
fruitfulness will be restored. To pass on, therefore, from one patch to
another, and again to another and another, is a common primitive
practice found in Africa, India, Ceylon, and many other parts of the
world, and is known as shifting cultivation. It even occurred in the
American continent some ten years or so ago before the Tennessee Valley
Authority was constituted by the late President of the United States of
America. In this shifting cultivation the fresh patch is usually cleared
by burning the jungle: this leaves the ash in situ, and thus retains
some of the mineral contents of the burnt vegetation for the benefit of
the coming crop. But it is a wasteful method, for a large aggregate area
is required to feed a small group, while a long period has to be
reckoned to replace the lost fertility. Indeed, this replacement is
seldom consummated. The larger trees suffer, the best part of the forest
is virtually destroyed. It will also be observed that after using up the
riches of the soil man actually does nothing to restore it--he merely
leaves it. This lazy practice constitutes the least satisfactory of many
agricultural systems and, entailing constant small movements of working
area on the part of those practicing it, is no foundation for a settled
civilization. It does, however, show that primitive tribes not only
realized the fact that fertility can be exhausted, but also understood
how it could be restored.


THE HARNESSING OF THE NILE

A much more satisfactory method of restoring soil fertility was evolved
in the great river valley of the Nile which, according to some
theorists, was the original home of agriculture proper. It is the
peculiarity of this great river that it overflows once a year with great
regularity, bearing suspended in its flood an accumulation of fertile
silt washed down from its catchment basin; this accumulation, rich in
both mineral and organic matter, is gently deposited and is capable of
yielding an abundant harvest. The process continued for centuries. Early
engineering skill led the silt-laden water to embanked fields by means
of inundation canals. The deposit was trapped just where it was needed
and the land was at the same time saturated with water. When the
embanked fields were dry enough, they were ploughed and sown: no rain
fell and no more water was needed for a full crop. The annual additions
of rich silt made this method of farming permanent. In this way there
grew up settled habitations, a great civilization, an historic people.

This basin system of irrigation in Egypt, which is perhaps the best and
most permanent that can be devised, has of recent years been replaced by
another--perennial irrigation--by which the same field can be watered
periodically to allow of cotton being grown. For this purpose the Nile
has been impounded and a vast reservoir has been created for feeding the
canals. But unless the very greatest care is taken to restore and then
to maintain the compound soil particles by means of constant dressings
of freshly prepared humus these modern methods are doomed. The too
frequent flooding of the close silts of this river valley will lead to
the formation of alkali salts and then to the death of the soil. This
will be the fate of Egypt if the powers-that-be persist in the present
methods of cultivation of cotton and do not realize before it is too
late that their ancient system of irrigation is, after all, the best.
Will a few years of cotton growing make up for the loss of the soil on
which the yew, life of Egypt is based? On the answer to this question
the future of the Nile valley will depend.


STAIRCASE CULTIVATION

Few areas on the earth's surface are so fortunate. What the great river
bestowed on the lucky Egyptians has had to be created in other parts of
the world, sometimes in the most unpromising conditions. The so-called
staircase cultivation of the ancient Peruvians is regarded as one of the
oldest forms of agriculture known to us--it dates from the Stone Age.
Without metal tools this people could not remove the dense forest
growths of the humid South American valleys. They were driven to the
upland areas under grass, scrub, or stone. Here they constructed
terraced fields up the slopes of the mountains, tier upon tier,
sometimes as many as fifty tiers rising one above the other. The outer
retaining walls of these terraces were made of large stones fitted into
each other with such accuracy that even at the present day a knife blade
cannot be inserted between them. Inside these walls were laid coarse
stones and over these clay, then layers of soil several feet thick, all
of which had to be imported from beyond the mountains. Just sufficient
slope was given to each tiny field for watering, water also being
brought in stone aqueducts from immense distances--one aqueduct of
between 400 and 500 miles has been found traversing the mountain slope
many hundreds of feet above the valley. Thus a series of gigantic flower
pots were formed and in these were grown the crops to nourish a nation
and to establish a civilization.

The results of such incredible labour are still to be seen, but the Inca
nation itself has vanished. However, in the Hunzas living in a high
mountain valley of the Gilgit Agency on the Indian frontier we have an
existing demonstration of what a primitive system of agriculture can do
if the basic laws of Nature are faithfully followed. The Hunzas are
described as far surpassing in health and strength the inhabitants of
most other countries; a Hunza can walk across the mountains to Gilgit
sixty miles away, transact his business, and return forthwith without
feeling unduly fatigued. In a later chapter we shall point to this as
illustrative of the vital connection between a sound agriculture and
good health. The Hunzas have no great area from which to feed
themselves, but for thousands of years they have evolved a system of
farming which is perfect. Like the ancient Peruvians they have built
stone terraces, whose construction admits of admirable soil drainage and
therefore of admirable soil aeration--for where water drains away
properly air is abundantly drawn in. As in the ancient Peruvian system,
irrigation is employed to obtain the water and it is not without
interest that this water is glacier water bringing down continual
additions of fine silt ground out from the rocks by the great cap of
ice. It is probable, though it has not been investigated, that the
mineral requirements of the fields are thus replenished to a remarkable
degree. To provide the essential humus every kind of waste, vegetable,
animal, and human, is mixed and decayed together by the cultivators and
incorporated into the soil; the law of return is obeyed, the unseen part
of the revolution of the great Wheel is faithfully accomplished.


THE AGRICULTURE OF CHINA

It is this return of all wastes to the soil, including the mud of ponds,
canals, and ditches, which is the secret of the successful agriculture
of the Chinese. The startling thing to realize about this peasant nation
of over four hundred million souls is the immense period of time over
which they have continued to cultivate their fields and keep them
fertile, at least 4,000 years. This is indeed a contrast to the shifting
cultivation of the African and it may be observed here that the greatest
misfortune of the African continent has been that it never came into
contact with the agricultural peoples of the Far East and never revised
its systems of cultivation in the light of the knowledge it might
thereby have gained--the great lesson of the Nile basin was not truly
apprehended and has had no influence outside Egypt, whereas over large
parts of eastern Asia the central problem of agriculture was solved very
early, empirically and not by a process of scientific investigation, yet
with outstanding success.

The Chinese peasant has hit on a way of supplying his fields with humus
by the device of making compost. Compost is the name given to the result
of any system of mixing and decaying natural wastes in a heap or pit so
as to obtain a product resembling what the forest makes on its floor:
this product is then put on the fields and is rich in humus. The Chinese
pay great attention to the making of their compost. Every twig, every
dead leaf, every unused stalk is gathered up and every bit of animal
excrete and the urine, together with all the wastes of the human
population, are incorporated. The device of a compost heap is clever. By
treating this part of the revolution of the Wheel as a special process,
separated from the details of cultivation, time is gained, for the
wastes mixed in a heap and kept to the right degree of moisture decay
very quickly, and successive dressings can be put on the soil, which
thus is kept fed with just what it needs: there is no pause while the
soil itself manufactures from the raw wastes the finished humus. On the
contrary, everything being ready and the humus being regularly renewed
at frequent intervals, the soil is able to feed an uninterrupted
succession of plants, and it is a feature of Chinese cultivation that
one crop follows another without a pause, indeed crops usually overlap,
the ripe crop being skilfully removed by hand from among the young
growing plants of the succeeding planting or sowing. In short, what the
Chinese farmer really does is ingeniously to extend his area. He, so to
say, rolls up the floor of the forest and arranges it in a heap. The
great processes of decay go on throughout that heap, spreading
themselves over the whole of the internal surface of the heap, that is,
over the whole of the surfaces implied in the juxtaposition of every
piece of waste against every other. He also overcomes the smallness of
the superficial area of his holding by increasing the internal surface
of the pore spaces of his soil. This is what matters from the point of
view of the crop--the maximum possible area on which the root hairs can
collect water and food materials for the green leaf. To establish and to
maintain this maximum pore space there must be abundant humus, as well
as a large and active soil population.

Thus is created the most intensive agriculture which the world has so
far seen. Each Chinese family lives on the produce of a very tiny piece
of ground, an area which would mean downright starvation in most other
countries. In spite of great calamities which repeat themselves,
principally floods, the causes of which will be mentioned hereafter, the
Chinese peasant may be said to be, on the whole, well nourished. His
resisting power to the many frightful diseases, sufficient to kill off
most other populations, has been noted, while the standard of culture
which he has reached and has maintained over the long period of his
existence rivals the contributions of Western civilization.

He is indeed the classic example of a nation which has conserved the
fertility of its soil. Other nations have done the same, but none over
so long a period or on so vast an area. Is it legitimate to interpret
the history of the nations by the way in which they have made use of the
land which chance or their own velour assigned to them? We have
considered some instances where attempts have been made to conserve
fertility with greater or lesser success. Let us now turn to some
different examples.


THE AGRICULTURE OF GREECE AND ROME

The agricultural history of the ancient Greeks is not altogether clear.
But one thing is certain: in common with most other Mediterranean
peoples they permitted an extraordinary amount of destruction of forest
growths over some of the areas bordering on this great inland sea.
Greece is now a land bare of trees and the continued depredations of the
goat have done untold harm to any young growths that have attempted to
survive. Whether this process began on a large scale very early and
whether the result was a severe disturbance of the drainage of a not
very fruitful country, extending on the one hand the area of marsh and
on the other inviting erosion, is not certain. Such conditions would
affect first the crops and then those who fed off them--subtle forms of
undernourishment and disease would appear. The theory has been put
forward that the extraordinary and unexplained collapse of the Greek
nation in the fourth and third centuries B.C., after a period of the
highest vigour and culture, was due to the spread of malaria. It is a
theory which is very reasonable and would explain much.

The case of the Romans, another Mediterranean people, is not quite the
same. For many centuries they maintained a flourishing agriculture to
which they paid great attention. The backbone of the nation throughout
its greatest period was the staunch mass of smallholders, each engaged
on cultivating his own farm and only breaking off at intervals to pursue
political matters with great vigour or to fight short summer campaigns
with the utmost zest. In spite of the attractions of the metropolis and
of the wonderful educational influence with which city life shaped law,
thought, and conduct, the rural background was conserved and valued;
religion remained rather rural throughout and never got very much beyond
the peasant outlook. It was the necessity for fighting prolonged foreign
campaigns which destroyed all this. Then came the fatal attractions of
slave labour. The smallholder was tempted or indeed was obliged to
desert his holding for years. Such holdings began to be bought up, for
wealth accumulated from the spoils of the East. Slaves were drafted in
to work these agglomerations of great estates: the evil latifundium,
which means the plantation in its worst form, spread everywhere. The
final phase was reached when tillage was given up for the cheaper
pastoral industry: where there had been countless flourishing homesteads
now ranged great herds of cattle tended by a few nomadic shepherd
slaves.

This disastrous change, which was deeply deplored by such writers as
Cicero, lasted and, except in northern Italy, was not made good. A few
years ago it was possible to see on a mere day's excursion away from
Rome a wild shepherd tending his sheep over a ruined countryside which
might have been carved out of the most ancient of wildernesses, so
entirely was it denuded of all traces of tillage or of the care of man.
There must have been some profound upsetting of the balanced processes
of Nature to reduce so fertile a country as Italy to such a state and
Nature in revenge has preferred to continue her revolution of the Wheel
on the lowest gear, spreading her marsh, her scrub, and her desert,
where once there were fields and meadows.

Having largely destroyed the food-bearing capacity of the Italian
peninsula, the Romans were forced to feed their swollen cities from
elsewhere. For the dispossessed rural population drifted to the towns,
which became further congested with a great influx of foreigners and
foreign slaves: all had to be fed, and Alexandria and Antioch were
problems no less great than Rome. First Sicily and then North Africa, at
that time great wheat-growing countries, were exhausted. We cannot trace
the process and do not know how much to attribute to a false economy,
how much to the ravages of centuries of war, as wave after wave of
conquerors disputed possession. When these countries reappear after such
cataclysms, Sicily is a wild pastoral country, North Africa, except for
a few coastal tracts and, of course, always Egypt, a desert.


FARMING IN THE MIDDLE AGES

The rest of the continent of Europe was more fortunate. Out of the
lingering shadows of the Roman Empire there finally emerged into
medieval times a system of agriculture which held its own well into the
nineteenth century. Such a long history is an honourable one and we may
agree that this system, that of mixed husbandry, was in many essentials
excellent. Except where a frozen legal system ground down the
cultivator--'trembling peasants gathering piteous harvests'--both the
large farm and the smallholding, the landlord and the tenant, survived
in good health and considerable comfort. Food was abundant and
nourishing, and above all the soil remained in good heart.

The system depended on certain principles. In the first place, animal
husbandry was practiced alongside of the production of vegetable crops:
there was thus a supply of manure. The manure was not made on the most
perfect system. The European manure heap, normally regarded as the
inevitable method of collecting and storing animal wastes, is
nevertheless most inefficient, as will be pointed out in a later chapter
(p. 192). But it has played a prime role in maintaining the fertility of
our continent, although it is wasteful and extravagant, unhealthy, and
unnatural: with the help of the manure heap the return of much of the
wastes of farming was assured to the land.

The use of the cesspit was even less successful and it is not surprising
that water-borne sewage, when once invented, rapidly replaced it:
unfortunately this permitted the final escape of valuable wastes to the
sea. To this came to be added, also in the course of the nineteenth
century, the further loss of all dustbin refuse which, again on the
dictates of the new sanitary science, was destroyed by burning or was
buried in unused tips. Nevertheless, until these modern sewage disposal
methods were developed, it is significant that all material wastes went
back to the soil in however imperfect a way.

A third principle in conserving fertility was the fallow. Arable land
was rested by allowing it to remain idle for a year or for a longer
period by the establishment of a temporary carpet of grass and weeds. A
part at least of the advantage of the bare fallow was the benefit
conferred by the weeds. When laid down to grass for sheep, the green
carpet rapidly deposited a mass of vegetable wastes under the turf
which, with the turf and the animal wastes deposited thereon, provided
all the raw materials for sheet-composting when the land came under the
plough. Both these methods have been employed in European farming for
many centuries and did much to conserve the fertility of the soil.

As long as all these principles governed European farming it could
roughly hold its own, although a slow running down of soil fertility
remained at all times a possibility, as will be seen in the next
chapter. It began to break down seriously with the advent of the
Industrial Revolution. But before dealing with the changes thus brought
about in European agriculture it will be illuminating to examine in
greater detail the story of one people, our own, in terms of the use
made by the community of soil fertility. We shall see that, in spite of
the great and advantageous practices to which we have alluded, soil
fertility was subtly and gradually used up. This has determined much in
our national affairs.




CHAPTER IV



THE MAINTENANCE OF SOIL FERTILITY IN GREAT BRITAIN


Many accounts of the way the present system of farming in Great Britain
has arisen have been published. The main facts in its evolution from
Saxon times to the present day are well known. Nevertheless, in one
important respect these surveys are incomplete. Nowhere has any attempt
been made to bring out the soil fertility aspect of this history and to
show what has happened all down the centuries to that factor in crop
production and animal husbandry--the humus content of the soil--on which
so much depends. The present chapter should be regarded as an attempt to
make good this omission.


THE ROMAN OCCUPATION

At the time of the Roman invasion most of the island in which we are
living was under forest or marsh: only a portion of the uplands was
under grass or crops: the population was very small. After the conquest
of the country the Romans began to develop it by the creation on the
areas already cleared of an agricultural unit--new to Great
Britain--known as the villa. These villas were large farms under single
ownership run by functionaries each responsible for a particular type of
animal or crop and worked by slave labour. These units followed to some
extent the methods of the latifundia of Italy and were designed for the
production of food for the legions garrisoning the island and those
stationed in Gaul. Wheat--an exhausting crop--was an important item in
Roman agriculture, for the reason that this cereal provided the chief
food (frumentum) of the soldiers. The extent of the export of grain to
Gaul will be evident from the fact that in the reign of the Emperor
Julian no less than 800 wheat ships were sent from Britain to the
Continent.

The exhaustion of the soils of the island began even before the Roman
occupation. The heavy soil-inverting mould board plough, which
invariably wears out the land, was already in use when the Romans
arrived, and was probably brought by the Belgic tribes who conquered and
settled in the south-eastern part of the country. They lived in
farmsteads and cultivated large open fields. They were highly skilled
agriculturists and exported to Gaul a considerable quantity of their
main product--wheat. This practice was developed by the Roman villas
which followed and in this way the slow exhaustion of the lighter soils
of the downlands of the south-east became inevitable.

After an occupation which lasted some 400 years and which contributed
little or nothing of permanent value to the agriculture of the island
beyond some well-designed roads, the legions evacuated the island and
left the Romanized population to look after itself. This they failed to
do: the country was soon conquered by the Saxon invaders, in the course
of which much destruction of life and property took place. One result
was the creation of a new type of farming.


THE SAXON CONQUEST

The settlement of Nordic people in our island is the governing event
both of British history and of British agriculture. The new settlers had
inhabited the belts of land around the Weser and the Elbe and their
first contact with Britain was as raiders; their operations were in the
nature of reconnaissance to ascertain the chances of settlement. The
Anglo-Saxon migration to Britain was a colonization preceded by
conquest, in which the farming system of the Romanized population was,
in the midland area at any rate, destroyed. In the east, south-east, and
western portions of the island some relics of Roman and Celtic methods
survived.

Our forefathers brought with them from the opposite shores of the North
Sea their wives, children, livestock, and a complete fabric of village
life. The immigrants, being country folk, wanted to live in rural huts
with their cattle round them and their land nearby, as they did in
Germany. The numerous villages they formed reproduced in all essentials
those they had left behind on the mainland. Our true English villages
are, therefore, not Celtic, are not Roman, but purely and typically
German.

The Roman villas were replaced by a new system of farming--the Saxon
manor--in which the tenants held land in return for service. The lord
and his retainers shared the land, each bound to perform certain duties
determined by custom. The manors took centuries to evolve. By A.D. 800
they had developed into a permanent system which provided the material
for the Domesday Book of the Normans, by which taxation was assessed and
a rigid feudal system became firmly established.


THE OPEN-FIELD SYSTEM

The first general feature that strikes us in early Anglo-Saxon England
is the strip cultivation of the arable land on the open-field system.
This system was a communal agricultural institution started by people
who had to get a living out of the soil. They had progressed as far as
to use the plough and had a common fund of experience. Everyone pursued
the same system of farming. The arrangement of the open fields was,
however, by no means uniform. No fewer than three distinct types arose,
corresponding to as many different influences exerted by people who had
early occupied the country. The large central midland area, stretching
from Durham to the Channel and from Cambridgeshire to Wales, is the
region where Germanic usage prevailed. The south-east was characterized
by the persistence of Roman influence, a circumstance which implies that
the conquest was less destructive there than in the north and west. The
counties of the south-west, north-west, and the north retained Celtic
agrarian usages in one form or another, which is easily understood in
view of the difficulty with which, as we know, these districts were
slowly overpowered by the invaders. The midland area was thus the region
where the Anglo-Saxons were most firmly established and where the
subjugation of the fifth century was most thorough. The Romano-Celtic
people who remained were not numerous enough to preserve any traces of
Roman or Celtic methods of tilling the soil.

Throughout this extensive region a two-field and a three-field system,
or sometimes a mixture of the two, prevailed. This field arrangement was
a custom prevalent in Germany, especially east and south of the Weser.
The chief characteristic of the two-and three-field type of tillage was
the distribution of the parcels of arable land (which made up the
holdings of the customary tenants) equally amongst the two or three
fields. The cropping was so arranged that one field in the two-field
system and two fields in the three-field system were cropped every year,
and thus one-half or one-third of the township's arable land lay fallow
and was used for common grazing--a point which is always emphasized in
the midland system.

Besides the cultivated open fields, for which the best land was always
used, the village lands consisted of grassland for mowing on the wetter
parts, and commons or woodlands on the poorer parts.

Ploughing was the all-important operation of medieval tillage and was
carried out on a co-operative basis, and demanded a team of eight
draught animals yoked to a heavy plough. This, of course, was beyond the
reach of any but the largest and most prosperous tenants. Communal
ploughing in Saxon times was, therefore, inevitable. It was the
difficulty of replacing this communal ploughing that delayed
agricultural progress in many parts of the country.

The open-field system repeated itself for centuries, not only in England
but in a great part of Europe--nations living under very different
conditions, in very different climates, and on very different soils
adopted the open-field system again and again without having borrowed it
from each other. This could not but proceed from some pressing
necessity. The open-field system is communal in its very essence. Every
trait which makes it strange and inconvenient from the point of view of
individualistic interests renders it highly appropriate to a state of
things ruled by communal conceptions--right of common usage--communal
arrangements of ways and time of cultivation. These are the main
features of open-field husbandry and all point to one origin--the
formation in early Anglo-Saxon society of a village community of
shareholders of free and independent growth.

It must be borne in mind that the open-field prevailed during the period
of national formation of the English people and its influence on the
life of the village community must have been very great. The sense of
personal responsibility, which the system of communal work created, made
it a vital factor in the social education of the people.


THE DEPRECIATION OF SOIL FERTILITY

Open-field farming is, as a rule, balanced: the fertility used up in
growth is made good before the next crop is sown. Compared with our
modern standards, however, the yield is remarkably low and the removal
of fertility by such small crops is made up for by the recuperative
processes operating in the soil (non-symbiotic fixation of nitrogen and
so forth). The surplus of available humus originally left by the forest
is depleted at an early stage and an equilibrium is established, the
yield adjusting itself to the amount of fertility added each year by
natural processes, this in its turn is influenced by climate and methods
of cultivation.

For example, in the peasant cultivation of north-west India at the
present day a perfect balance has been established between losses and
gains of fertility. The village land on which corn crops are grown has
been cultivated for upwards of 2,000 years without manure beyond the
droppings of the livestock during the fallow period between harvest and
the rains. But the Indian cultivators use primitive scratch ploughs and
are most careful not to draw on the reserves of organic material in the
soil, as its texture depends on this. They produce crops entirely on the
current account provided by the annual increments of fertility. The
yield has settled down to 8 maunds (658 lb. per acre) of wheat on
unirrigated land, and 12 maunds (987 lb.) of wheat on irrigated land,
and this yield has been constant for many centuries.

The same processes were operating in the English open fields. The
reserve of humus in the soils originally under forest, which the Saxons
brought into cultivation, was soon used up and the yield was determined
by the annual additions of fertility to the soil by natural means. But
in our cold and sunless climate and on our ill-drained, poorly aerated
soils this is far less than in the semi-tropical conditions of northern
India.

Moreover, and this point must be stressed, the Saxons from the earliest
times used a soil-inverting plough, which has a marked tendency to
exhaust the humus in the soil if provision is not made for the regular
supply of sufficient farmyard manure. In fact, recent experience in many
parts of the world is proving that the continued use of heavy
soil-inverting, tractor-driven implements, without sufficient farmyard
manure to manure the land, promptly leads to catastrophic consequences.

The first recorded references to the mould board plough speak of it in
Gaul, but some authorities quoted by Vinogradoff (The Growth of the
Manor) suggest that it was borrowed by the Germanic people from the
Slavs, and in view of the soil types found in Slav territory this may
easily be so. The evolution of the big plough was due to soil
requirements as settled agricultural life developed in the heavy, moist
soils of north Europe after the forests had been cleared.

The mould board plough determined the lay-out of the open fields. It
divided the arable areas into a succession of lands. It needed a
headland to turn on, and there was a limit to the length of furrow a
team of oxen could plough before needing the relief got by stopping and
turning. This furrow-long or furlong became one of our units of length.
It was usual to keep the land in high ridges running along the slopes to
facilitate surface drainage, an important point in England. The ridges
varied in width according to the nature of the soil. In very heavy clays
they were sometimes no more than three yards wide. In lighter soils they
might be twenty-two yards wide. These ridges may be seen in many places
to-day on grassland which was under the plough in earlier centuries.
From this brief description it will be seen that the open fields
cultivated with the heavy medieval plough were laid out in strips.

The main feature of the heavy mould board plough was its high
penetrating power, and it could be used on the heavier types of soil
where the light scratch plough of the Celts and Italians would be
useless. It thus enabled the cropped area in England to be greatly
extended by the cultivation of the heavy soil of the valleys and plains
which first had to be slowly carved out of the forest. It owed its
superiority to an iron share, a courter, and a wooden mould board so
suitable on wet land. This primitive implement gave us the plough as we
know it to-day. The principle of our modern plough is identical and,
except for the fact that it is now made entirely of iron, it is almost
the same in detail.

The open-field system of the Middle Ages was bound to fail because it
involved burning the candle at both ends and also in the middle. First
the natural recuperation processes in the soil were hampered by low
temperatures and poor soil aeration; second, such supplies of farmyard
manure as were available were by custom mostly bestowed on the lord's
demesne lands, and besides were inadequate because only a portion of the
livestock could be wintered; finally the soil-inverting plough led to
the oxidation of the stores of soil humus faster than it could be
recreated and was bound to wear out the land.


THE LOW YIELD OF WHEAT

The failure of the open-field system is proved by the low yield of
wheat. All authorities agree that the yield of wheat in England during
the Middle Ages was at a very low level, though it does not appear to
have varied greatly. It may be noted that there was never any question
of complete exhaustion of the wheat-growing land, such as occurred in
Mesopotamia and in the Roman wheat-growing regions of North Africa,
where the soil, owing to over-cropping and in some instances to
over-irrigation aggravated by special climatic conditions, became
sterile and was transformed into desert. This could not so easily happen
in the moist, temperate climate of Great Britain. What happened in the
Middle Ages in England was that the yield of corn was not high enough
for the requirements of the growing social and economic life of the
country.

The material for a quantitative estimate of wheat yields in this period
is necessarily very scanty, but in the case of some large estates
records are available for a considerable period of years of the seed
sown in one year and the grain threshed in the following year, and these
form the basis of the best estimates of medieval yields. Sir William
Beveridge (Economic Journal Supplement, May 1927), using this method,
investigated the yield of wheat for the years 1200 to 1450 on eight
manors, including that of Wargrave, situated in seven different counties
belonging to the Bishop of Winchester. The average yield per acre was
1.17 quarters or 9.36 measured bushels, equivalent to 7.48 bushels of 60
lb. It is to be noted that these estimates were all from demesne lands
which were probably better cultivated and better manured than the land
of the customary tenants. Other authorities confirm these figures.

The figures of yield given above help to account for the changes which
marked the end of the Middle Ages. The amount of food was becoming
insufficient for the growing population. But another factor was steadily
developing, which finally assumed the dimensions of an avalanche and led
to t