PAY DIRT Farming & Gardening with Composts by J. I. RODALE Editor of Organic Gardening Magazine Introduction by Sir ALBERT HOWARD Author of The Soil and Health New York THE DEVIN-ADAIR COMPANY 1949 PAY DIRT, Copyright, 1945, by J. I. RODALE All rights reserved. Permission to use material from this book, except for short quotations for use in reviews, must be obtained in writing from the publishers. First Printing August, 1945 Second Printing December, 1945 Third Printing March, 1946 Fourth Printing November, 1946 Fifth Printing September, 1947 Sixth Printing February, 1948 Seventh Printing September, 1948 Eighth Printing, January, 1949 PRINTED IN U. S. A. INTRODUCTION A revolution in farming and in gardening is in progress all over the world. If I were asked to sum up in a few words the basis of this movement and the general results that are being obtained, I should reply that a fertile soil is the foundation of healthy crops, healthy live stock, and last but not least healthy human beings. By a fertile soil is meant one to which Nature's law of return has been faithfully applied, so that it contains an adequate amount of freshly prepared humus made in the form of compost from both vegetable and animal wastes. This revolution in crop production involves making the very most of the earth's green carpet—that marvelous machinery for producing all our food and a great deal of the raw materials needed by our factories. Both units of this natural factory—the green cells of the leaf and the power which drives them (the energy of sunlight)—owe nothing to mankind. They are the gifts of Providence which all the resources of Science cannot copy, still less improve. Mankind can only assist the food factory in two directions. He can look after the soil on which the green carpet rests and in which the roots of crops and the unpaid labour force of the soil— moulds, microbes, earthworms, and so forth—live and work. He can also by selecting crops by plant breeding methods make the most of the energy of sunlight and of the improved soil conditions. But the plant breeder must avoid one obvious blunder. He must not be content with improving the variety only, otherwise his labours will soon lead to the exhaustion of the soil. The improved variety will take more out of the ground and will soon become a boomerang. The plant breeder, therefore, must always be careful not to confine his attention to the variety, but must increase the fertility of the soil at the same time. Such crops will look after themselves, and insect and fungous pests will do little or no damage. How has the United States of America ministered to the country's green carpet? The answer is provided by the Year Book of the Federal Department of Agriculture of 1938, which was published under the title—Soils and Men. In this work the results of a careful appraisal of the cultivated soils of the country were recorded. It disclosed the alarming fact that no less than 253,000,000 acres, or 61 per cent of the total area under crops, had either been completely or partially destroyed, or had lost most of its fertility. This has arisen from misuse of the land which has resulted in widespread soil erosion. Soil erosion is the natural consequence of the collapse of the compound soil particles, on the maintenance of which the well-being both of the soil population and the crop depends. These compound particles are made up of fragments of mineral matter glued together by specks of organic matter provided by the activities of the invisible life of the soil. These soil organisms have to be constantly fed with fresh supplies of humus, otherwise the soil soon wears out. When we attempt to replace these supplies by means of artificial manures, we accelerate the wearing-out process. Nature in all such cases hits back by leaving the soil an inert mass of mineral fragments, in which the beneficial soil population are deprived of air, water, food, warmth, and shelter. The death of the soil and of its population is the natural consequence. Nature finally removes the ruins by wind or water to form either a desert or new soil somewhere else under the sea. What has been the effect of this neglect of the soil on the human population? The results are summed up in Alexis Carrel's masterpiece—Man The Unknown. In the United States no less than £700,000,000 a year is spent on medical care for dealing with disease of various kinds, much of which would never have occurred had the restitution of the manurial rights of the soil received proper attention. Failure to look after the soil under the green carpet does not pay. It leads to the destruction of large areas of land; it creates an inefficient population. All this can be put right if the law of return is followed and all the available vegetable and animal wastes of the country are converted into compost for the soil. Exactly how this should be done, what results on crops, live stock, and mankind will then be observed will be clear from a perusal of this book, the chapters of which I have just read with the most lively interest. Many things impressed me as this book developed. What gave me most pleasure was to discover that Mr. Rodale possesses that priceless quality—audacity— without which progress is never made. With no previous experience of the land and its ways, nevertheless he courageously acquired a farm, learned how to get it into a fertile condition, and then observed the results of compost on his crops, his live stock, and afterwards on himself and on the members of his family. He thus took his own advice before offering it to his countrymen in the pages of this book and of his new journal—Organic Gardening—which, as the years and months pass, goes from strength to strength. All this is very refreshing in a world which tends to become more and more superficial, due in large measure to that disease of civilization—fragmentation—by which such intimately related subjects as agriculture, food, nutrition, and health have become split up into innumerable rigid and self-contained little units, each in the hands of some group of specialists. The experts, as their studies become concentrated on smaller and smaller fragments, soon find themselves wasting their lives in learning more and more about less and less. The result is the confusion and chaos now such a feature of the work of experiment stations and teaching centres devoted to agriculture and gardening. Everywhere knowledge increases at the expense of understanding. The remedy is to look at the whole field covered by crop production, animal husbandry, food, nutrition, and health as one related subject and then to realize the great principle that the birthright of every crop, every animal, and every human being is health. ALBERT HOWARD. 14 Liskeard Gardens, Blackheath, London, S. E. 3 1st March, 1945 Contents INTRODUCTION BY SIR ALBERT HOWARD iii PART ONE—THE LIVING SOIL THE BIOLOGIC LIFE OF THE SOIL 3 THE EARTHWORM 8 THE MYCORRHIZA FUNGI 15 THE PENICILLIUM MOLD 21 PART TWO—COMPOST— THEORY AND PRACTICE SIR ALBERT HOWARD—FATHER OF SCIENTIFIC COMPOSTING 29 HOW TO MAKE A COMPOST HEAP 34 THE COMPOST PROCESS 42 LIME, WOOD ASH AND ROCKS 45 SPREADING COMPOST 56 COMPOST HEAPS FOR SMALL GARDENS 60 ANIMAL MANURES 65 SHORT CUTS IN COMPOST MAKING 75 ADVANTAGES OF COMPOST FARMING 83 PART THREE— THE DANGERS OF CHEMICAL FERTILIZERS ARE CHEMICAL FERTILIZERS NECESSARY? 95 CHEMICAL FERTILIZERS ARE TOO STRONG 104 CONDEMNED FARM LANDS—CHEMURGY 109 WEED KILLERS AND DISINFECTANTS 114 CHEMICAL VS. BIOLOGIC CONCEPTS 123 YOU HAVE TO KNOW YOUR CHEMISTRY 130 PART FOUR—HEALTH OR DISEASE FROM FOOD HUMAN HEALTH AND COMPOSTS—The Medical Testament 139 IS OUR HEALTH RELATED TO THE SOIL? 150 DISEASES OF FARM ANIMALS 157 PLANT DISEASE AND INSECT PESTS 164 POISON SPRAYS 174 SAFE MEANS OF CHECKING INSECTS AND DISEASE IN GARDENS 182 ORGANIC ORCHARDS l88 PART FIVE— GOOD AND BAD FARMING PRACTICES SOME PRACTICES, GOOD AND BAD 199 TO PLOW OR NOT TO PLOW 207 BURNING OVER LAND 214 ORGANIC VS. ARTIFICIAL POULTRY 218 CONCLUSION 231 BIBLIOGRAPHY 241 PART ONE The Living Soil I THE BIOLOGIC LIFE OF THE SOIL The soil is not, as many suppose, a dead, inert substance. It is very much alive and dynamic. It teems with bacteria, actinomycetes, fungi, molds, yeasts, protozoa, algae and other minute organisms. All are microscopic plants except the protozoa which represent animal life. As a group, these lower plants and animals are referred to as the biologic life of the soil. Although microbes have been studied and worked with by the medical profession and by industry for over seventy- five years they have been largely neglected in agriculture. This microbial population of the soil is concentrated mainly in the upper four or five inches where the bulk of the organic matter, their food, is to be found. When you get down to three feet you may find only thirty to forty thousand bacteria per gram of soil, whereas in the upper levels they may reach billions. In a very fertile soil the amount of bacteria in an acre may weigh as high as 600 pounds. When they die their decaying bodies turn to humus and enrich the soil. Most of them are beneficent, helpful organisms; a few are not. Normally they live together in a delicate, balanced relationship closely controlled by nature. If soil conditions get out of hand either because of the intrusion of foreign elements (certain strong chemicals, for example) or through lack of proper food, or climatic change, the inter-relationships become strained, and it is then more difficult to grow plants the way nature intended. The Society of American Bacteriologists has classified about 1,000 species of bacteria. Of this number only about 100 are pathogenic, that is, capable of bringing about disease in plant, animal or man. These microbes are the real manufacturers of plant food in the soil and not only do they make it but in some cases (the mycorrhiza fungi) actually feed it to the plant. Fungi and bacteria perform the very valuable function of breaking down or decomposing organic matter and thus conditioning the soil and its structure. Research workers of the U. S. Department of Agriculture have discovered two ways in which they do this: Decay bacteria secrete a mucus which glues fine particles of soil into masses that resist the washing effect of rains which otherwise would cause soil erosion, and fungi that feed on plants throw out thread-like filaments or mycelia which bind together soil particles into larger masses. More commonly known is the fact that nitrogen-fixing bacteria work in the roots of leguminous plants to extract nitrogen from the air. There are undoubtedly many other important soil inter- relationships. Algae may help bacteria. The latter may furnish food for protozoa. It seems to be a well-regulated little society. All it needs is a diet of the kind of food it likes and a few other necessary conditions. First there has to be sufficient aeration. Most soil bacteria need a certain amount of oxygen. Following the system of agriculture proposed here with its stress on composts, the soil structure becomes comparatively loose and porous, encouraging maximum microbial multiplication. Conversely, systems that depend overly on chemicals, find eventually a hardpacked soil unfriendly to soil organisms. Moisture is very important but there should not be too much of it. The physical structure of a soil gained by years of organic farming becomes perfect for retention of the proper amount of moisture. With a hard-packed soil you have either a desert-dry condition in which bacteria cannot live, or one too saturated with water, which encourages harmful anaerobic bacteria, that give rise to a condition of putrefaction rather than fermentation in the breaking down of organic material. The earth's microscopic citizens thrive when it is warm, that is, in a temperature between 70° to 100° F. Here again, a soil constantly enriched with organic matter becomes warmer earlier in the spring than one which has been abused with constant doses of strong chemicals. Experiments at Government stations have shown invariably that the darker a soil is the more warmth it will absorb. It is a generally accepted fact that the constant application of humus to soil will gradually darken it and eventually turn it almost black. As between a very dark and a yellowish soil there may be a temperature difference of as much as 8° to 10°. This matter of heat and light absorption is extremely important because if the soil warms up earlier in the spring, a farmer can get on to his land earlier. Another condition favorable to bacteria is a neutral or slightly acid soil; fungi can thrive in a more acid one. In forests where the soil is acid you will find fewer bacteria. There the work is performed mainly by fungi. It is axiomatic that for growing crops the more microbial life in the soil the better. Most soil text-books agree that the more fertile a soil is, the more bacteria and other soil micro- organisms will be found in it. In the same way it can safely be stated that the more organic matter is applied to soil the more soil organisms result. Sir E. John Russell in Soil Conditions and Plant Growth describes a bacterial count at the Rothamsted Agricultural Station in England. In a field treated with farmyard manure 28,860,000 bacteria were counted per gram of soil. Where complete minerals plus ammonium sulphate were used, only 15,100,000 bacteria were present. Lyon and Buckman in The