 CHAPTER VIII. Organic matter benefits soil productivity, not because it is present, but because all forms of organic matter in the soil, including its most stable form, humus, are disappearing. Microsial fungi and beneficial bacterial colonies around plant roots can exist only by consuming soil organic matter. The slimes and gums that cement soil particles into relatively stable aggregates are formed by microorganisms as they consume soil organic matter. Scats and casts that are soil crumbs form only because organic matter is being consumed. If humus declines, the entire soil ecology runs down and with it soil tilth and the health and productivity of plants. If you want to manage your garden soil wisely, keep foremost in mind that the rate of humus loss is far more important than the amount of humus present. However, natural processes remove humus without our aid or attention while the gardener's task is to add organic matter. So there is a very understandable tendency to focus on addition, not subtraction. But can we add too much? If so, what happens when we do? How much humus is soil supposed to have? If you measured the organic matter contents of various soils around the United States, there would be wide differences. Some variations on cropland are due to great losses that have been caused by mismanagement. But even if you could measure virgin soils never used by humans, there still would be great differences. Hans Jenny, a soil scientist at the University of Missouri during the 1940s, noticed patterns in soil humus levels and explained how and why this occurs in a wonderfully readable book, Factors in Soil Formation. These days, academic agricultural scientists conceal the basic simplicity of their knowledge by unnecessarily expressing their data with exotic verbiage and higher mathematics. In Jenny's time, it was not considered demeaning if an intelligent layman could read and understand the writings of a scientist or scholar. Any serious gardener who wants to understand the wide differences in soil should become familiar with factors in soil formation. About organic matter in virgin soils, Jenny said, Within regions of similar moisture conditions, the organic matter content of soil decreases from north to south. For each fall of 10°C 18°F in annual temperature, the average organic matter content of soil increases two or three times, provided that soil moisture is kept constant. Moist soil during the growing season encourages plant growth and thus organic matter production. Where the soil becomes dry during the growing season, plant growth slows or stops. So all things being equal, wet soils contain more organic matter than dry does. All organic matter eventually rots, even in soil too dry to grow plants. The higher the soil temperature, the faster the decomposition. But chilly, not frozen, soils can still grow a lot of biomass. So all things being equal, hot soils have less humus in them than cold ones. Cool, wet soils will have the highest levels. Hot, dry soils will be lowest in humus. This model checks out in practice. If we were to measure organic matter in soils along the Mississippi River, where soil moisture conditions remain pretty similar from south to north, we might find 2% in Sultry, Arkansas, 3% in Missouri, and over 4% in Wisconsin, where soil temperatures are much lower. In Arizona, unirrigated desert soils have virtually no organic matter. In Central and Southern California, where skimpy and undependable winter rains peter out by March, it is hard to find an unirrigated soil containing as much as 1% organic matter, while in the cool Maritime Northwest, reliable winter rains keep the soil damp into June, and the more fertile farm of pastures or natural prairies may develop as much as 5% organic matter. Other factors, like the basic mineral content of the soil or its texture, also influence the amount of organic matter a spot will create, and will somewhat increase or decrease the humus content compared to neighboring locations experiencing the same climate. But the most powerfully controlling influences are moisture and temperature. On all virgin soils, the organic matter content naturally sustains itself at the highest possible level, and average annual additions exactly match the average annual amount of decomposition. Think about that for a moment. Imagine that we start out with a plot of finely ground rock particles containing no life and no organic matter. As the rock dust is colonized by life forms that gradually build in numbers, it becomes soil. The organic matter created there increases nutrient availability and accelerates the breakdown of rock particles, further increasing the creation of organic matter. Soil humus steadily increases. Eventually a climax is sustained where there is as much humus in the soil as there can be. The peak plant and soil ecology that naturally lives on any site is usually very healthy and is inevitably just as abundant as there is moisture and soil minerals to support it. To me this suggests how much organic matter it takes to grow a great vegetable garden. My theory is that in terms of soil organic matter, vegetables grow quite well at the humus level that would peak naturally on a virgin site. In semi-arid areas, I'd modify the theory to include an increase as a result of necessary irrigation. Expressed as a rough rule of thumb, a mere 2% organic matter in hot climates, increasing to 5% in cool ones, will supply sufficient biological soil activities to grow healthy vegetables if the mineral nutrient levels are high enough too. Recall my assertion that what is most important about organic matter is not how much is present, but how much is lost each year through decomposition. For only by decomposing does organic matter release the nutrients it contains so plants can uptake them. Only by being consumed does humus support the microecology that so markedly contributes vitamins to plant nutrition, aggressively break down rock particles and release the plant nutrients they contain. Only by being eaten does soil organic matter support bacteria and earthworms that improve productivity and create better tilf. Here's something I find very interesting. Temperate climates having seasons and winter vary greatly in average temperature. Comparing annual decomposition loss from a hot soil carrying 2% humus with annual decomposition loss from a cooler soil carrying 5%, roughly the same amount of organic matter will decay out of each soil during the growing season. This means that in temperate regions we have to replace about the same amount of organic matter no matter what the location. Like other substantial colleges of agriculture, the University of Missouri ran some very valuable long term studies in soil management. In 1888 a never farmed field of native prairie grasses was converted into test plots. For 56 seeding years each plot was managed in a different but consistent manner. The series of experiments that I find the most helpful recorded what happens to soil organic matter as a consequence of farming practices. The Virgin Prairie had sustained an organic matter content of about 3.5%. The lines on the graph show what happened to that organic matter over time. Timothy grass is probably a slightly more efficient converter of solar energy into organic matter than was the original prairie. After 50 years of feeding the hay cut from the field and returning all the livestock's manure, the organic matter in the soil increased about half percent. Obviously green maneuvering has very limited ability to increase soil humus above climax levels. Growing oats and returning enough manure to represent the straw and grain fed to livestock, the field held its organic matter relatively constant. Growing small grain and removing everything but the stubble for 50 years greatly reduced the organic matter. Keep in mind that half the biomass production in a field happens below ground as roots. And keep in mind that the charts don't reveal the sad appearance the crops probably had once the organic matter declined significantly. Nor do they show that the seed produced on those degenerated fields probably would no longer sprout well enough to be used as seed grain. So new seed would have been imported into the system each season. Bringing with it new supplies of plant nutrients. Without importing that bushel or so of wheat seed on each acre each year, the curves would have been steeper and gone even lower. Corn is the hardest of the cereals on soil humus. The reason is wheat is closely broadcast in fall and makes a thick grassy overwintering stand that forms biomass out of most of the solar energy striking the field from spring until early summer when the seed forms. Leafy oats create a little more biomass than wheat. Corn on the other hand is frost tender and can't be planted early. It is also not closely planted but is sown in widely spaced rows. Corn takes quite a while before it forms a leafy canopy that uses all available solar energy. In farming lingo corn is a row crop. Vegetables are also row crops. Many types don't form dense canopies that soak up all solar energy for the entire growing season like a virgin prairie. As with corn the ground is tilled bare. So for much of the best part of the growing season little or no organic matter is produced. Of all the crops that a person can grow vegetables are the hardest on soil organic matter. There is no way that vegetables can maintain soil humus. Even if all their residues are religiously composted and returned. Soil organic matter would decline markedly even in an experiment in which we raised some small animals exclusively on the vegetables and returned all of their manure and urine too. When growing vegetables we have to restore organic matter beyond the amount the garden itself produces. The curves showing a humus decline at the University of Missouri give us a good hint as to how much organic matter we are going to lose from vegetable gardening. Let's make the most pessimistic possible estimate and suppose that vegetable gardening is twice as hard on soil as was growing corn and removing everything but the stubble and root systems. With corn about 40% of the entire organic matter reserve is depleted in the first 10 years. Let's suppose that vegetables might remove almost all soil humus in 10 years or 10% each year for the first 10 years. This number is accrued and for most places in America a widely pessimistic guess. However 10% loss per year may understate losses in some places. I have seen old row crop soils in California's Central Valley that look like white colored blowing dust. Nor does a 10% per year estimate quite allow for the surprising durability I observe in the still black and rich looking old vegetable seed fields of Western Washington State's Skagit Valley. These cool climate fields have suffered chemical farming for decades without having been completely destroyed. Yet how much loss is 10% per year? Let's take my own garden for example. It started out as an old hay pasture that hadn't seen a plow for 25 or more years and where for the 5 years I've owned the property the annual grass production is not cut, baled and sold but is cut and allowed to lay in place. Each year's accumulation of minerals and humus contributes to the better growth of the next year's grass. Initially my grass had grown a little higher and a little thicker each year but the steady increase in biomass production seems to have tapered off in the last couple of years. I suppose by now the soil's organic matter content probably has been restored and is about 5%. I allocate about one acre of that old pasture to garden land. In any garden year my shifting gardens occupy one-third of that acre. The other two-thirds are being regenerated in healing grass. I measure my garden in fractions of acres. Most city folks have little concept of an acre. It's about 40,000 square feet or a plot 200 feet by 200 feet. Give or take some, the plowpan of an acre weighs about 2 million pounds. The plowpan is that 7 inches of topsoil that is flipped over by a mold-bored plow, the 7 inches where most biological activity occurs, where virtually all of the soil's organic matter resides. 2 million pounds equals 1,000 tons of topsoil in the first 7 inches of an acre. 5% of that 1,000 tons can be organic matter, up to 50 priceless tons of life that changes 950 tons of dead dust into a fertile productive acre. If 10% of that 50 tons is lost as a consequence of one year's vegetable gardening, that amounts to 5 tons per acre per year lost or about 25 pounds lost per 100 square feet. Patience reader, there is a very blunt and soon to be a very obvious point to all of this arithmetic. Visualize this, lime is spread at rates up to 4 tons per acre. Have you ever spread 1 ton per acre or 50 pounds of lime over a garden 30 by 30 feet? Mighty hard to accomplish. Even 200 pounds of lime would barely whiten the ground of a 1,000 square foot garden. It is even harder to spread a mere 5 tons of compost over an acre or only 25 pounds on a 100 square foot bed. It seems as though nothing has been accomplished. Most of the soil still shows. There is no layer of compost, only a thin scattering. But for the purpose of maintaining humus content of vegetable ground at a healthy level, a thin scattering once a year is a gracious plenty. Even if I were starting with a totally depleted, dusty, absolutely humusless, ruined old farm field that had no organic matter whatsoever and I wanted to convert it to a healthy vegetable garden, I would only have to make a one-time amendment of 50 tons of ripe compost per acre or 2,500 pounds per 1,000 square feet. Now 2,500 pounds of humus is a groaning, spring-sagging, long-bed pickup load of compost heaped up above the cab and dripping off the sides. Spread on a small garden that's enough to feel a sense of accomplishment about. Before I knew better, I used to incorporate that much composted horse manure once or twice a year. And when I did add a half-inch thick layer, that's about what I was applying. Fertilizing Vegetables with Compost Will a 5 ton per acre addition of compost provide enough nutrition to grow great vegetables? Unfortunately, the answer usually is no. In most gardens, in most climates, with most of what passes for compost, it probably won't. That much compost might well grow decent wheat. The factors involved in making this statement are numerous and too complex to fully analyze in a little book like this one. They include the intrinsic mineralization of the soil itself, the temperature of the soil during the growing season, and the high nutritional needs of the vegetables themselves. In my experience, a few alluvial soils that get regular small additions of organic matter can grow good vegetable crops without additional help. However, these sites are regularly flooded and replenished with highly mineralized rock particles. Additionally, they must become very warm during the growing season. But not all rock particles contain high levels of plant nutrients, and not all soils get hot enough to rapidly break down soil particles. Soil temperature has a great deal to do with how effectively compost can act as fertilizer. Sandy soils warm up much faster in spring, and sand allows for a much freer movement of air, so humus decomposes much more rapidly in sand. Perhaps a sunny, sandy garden on a south-facing slope might grow pretty well with small amounts of strong compost. As a practical matter, if most people spread even the most potent compost over their gardens at only 25 pounds per 100 square feet, they would almost certainly be disappointed. Well then, if 5 tons of quality compost to the acre isn't adequate for most vegetables, what about using 10 or 20 tons of the best? Will that grow a good garden? Again, the answer must allow for a lot of factors, but is generally more positive. If the compost has a low C to N, and that compost, or the soil itself, isn't grossly deficient in some essential nutrient, and if the soil has a coarse, airy texture that promotes decomposition, then somewhat heavier applications will grow a good-looking garden that yields a lot of food. However, one question that is rarely asked, and even more rarely answered satisfactorily in the holistic farming and gardening lore, is, precisely how much organic matter or humus is needed to maximize plant health and the nutritional qualities of the food we're growing? An almost equally important corollary of this is, can there be too much organic matter? This second question is not of practical consequence for biological grain livestock farmers because it is almost financially impossible to raise organic matter levels on farm soils to extraordinary levels. Large-scale holistic farmers must grow their own humus on their own farm. Their focus cannot be on buying and bringing in large quantities of organic matter. It must be on conserving and maximizing the value of the organic matter they produce themselves. Where you do hear of an organic farmer, not vegetable grower but cereal livestock farmer, building extraordinary fertility by spreading large quantities of compost, remember that this farmer must be located near an inexpensive source of quality material. If all the farmers wanted to do the same, there would not be enough to go around at an economic price, unless, perhaps, the entire country became a closed system like China. We would have to compost every bit of human excrement in organic matter, and there still wouldn't be enough to meet the demand. Even if we became as efficient as China, keep in mind the degraded state of China's upland soils and the rapid desertification going on in their semi-arid west, China is robbing Peter to pay Paul and may not have a truly sustainable agriculture either. I frequently encountered a view among devotees of the organic gardening movement that if a little organic matter is a good thing, then more must be better and even more better still. In organic gardening magazine and Rodale garden books, we read eulogies to soils that are so high in humus and so laced with earthworms that one can easily shove their arm into the soft earth elbow-deep that must yank it out fast before all the hairs have been chewed off by worms, where one must jump away after planting corn seeds lest the stalk poke you in the eye, where the pumpkins average over a hundred pounds each, where a single trellist tomato vine covers the entire south side of a house and yields bushels, all due to compost. I call believers of the organic faith capital-o organic gardeners. These folks almost inevitably have a pickup truck used to gather in their neighborhoods, leaves and grass clippings on trash day and to haul home loads from local stables into chicken ranches. Their large yards are ringed with compost bins and their annual spreadings of compost are measured in multiples of inches. I was one once myself. There are two vital and slightly disrespectful questions that should be asked about this extreme of gardening practice. Is this much humus the only way to grow big, high-yielding organic vegetable gardens? And two, are vegetables raised on soils super high in humus maximally nutritious? If the answer to the first question is no, then a person might avoid a lot of work by raising the nutrient level of their soil in some other manner acceptable to the organic gardener. If the answer to the second question is less nutritious, then serious gardeners and homesteaders who are making homegrown produce into a significant portion of their annual caloric intake had better reconsider their health assumptions. A lot of organic gardeners cherish ideas similar to the character Woody Allen played in his movie Sleeper. Do you recall that movie? It's about a contemporary American who, coming unexpectedly close to death, is frozen and then reanimated and healed two hundred years in the future. However, our hero did not expect to die or be frozen when he became ill, and upon awakening, believes the explanation given to him is a put-on and that his friends are conspiring to make him into a fool. The irritated doctor in charge tells Woody to snap out of it and be prepared to start a new life. This is no joke, says the doctor. All of Woody's friends are long since dead. Woody's response is a classic line that earns me a few chuckles from the audience every time I lecture. All of my friends can't be dead. I own a health food store and we all ate brown rice. Humus and the nutritional quality of food. I believe that the purpose of food is not merely to fill the belly or to provide energy, but to create and maintain health. Ultimately, soil fertility should be evaluated not by humus content nor microbial populations, nor earthworm numbers, but by the long-term health consequences of eating the food. If physical health degenerates, is maintained, or is improved, we have measured the soil's true worth. The technical name for this idea is a biological assay. Evaluating soil fertility by biological assay is a very radical step for connecting long-term changes in health with the nutritional content of food and then with soil management practices invalidates a central tenet of industrial farming that to both yield is the ultimate measure of success or failure. As Newman Turner, an English dairy farmer and disciple of Sir Albert Howard, put it, the orthodox scientist normally measures the fertility of a soil by its bulk yield with no relation to effect on the ultimate consumer. I have seen cattle slowly lose condition and fall in milk yield when fed entirely on the abundant produce of an apparently fertile soil. Though the soil was capable of yielding heavy crops, those crops were not adequate in themselves to maintain body weight and milk production in the cow without supplements. That soil, though capable of above-average yields and by the orthodox quantitative measure regarded as fertile, could not, by the more complex measure of ultimate effect on the consumer, be regarded but anything but deficient in fertility. Fertility, therefore, is the ability to produce at the highest recognized level of yield, crops of quality which, when consumed over long periods by animals or man, enable them to sustain health, bodily condition and high level of production without evidence of disease or deficiency of any kind. Fertility cannot be measured quantitatively. Any measure of soil fertility must be related to the quality of its produce. The most simple measure of soil fertility is its ability to transmit through its produce fertility to the ultimate consumer. Howard also tells of creating a super-healthy herd of work oxen on his research farm in Indore, India. After a few years of meticulous composting and restoration of soil life, Howard's oxen glowed with well-being. As a demonstration he intentionally allowed his animals to rub noses across the fence with neighboring oxen known to be infected with hoof and mouth and other cattle plagues. His animals remained healthy. I have read so many similar accounts in the literature of the organic farming movement that in my mind there is no denying the relationship between the nutritional quality of plants and the presence of organic matter in soil. Many other organic gardeners reached the same conclusion. Most gardeners do not understand one critical difference between farming and gardening. Most agricultural radicals start farming on run-down land grossly deficient in organic matter. The plant and animal health improvements they describe come from restoration of soil balance from approaching a climax, humus level, much like I've done in my pasture, by no longer removing the grass. Bone gardeners and market gardeners near cities are able to get their hands on virtually unlimited quantities of organic matter. Encouraged by a mistaken belief that the more organic matter the healthier they enrich their soils far beyond any natural capacity. Often this is called building up the soil. But increasing organic matter in gardens well above a climax ecology level does not further increase the nutritional value of vegetables and in many circumstances will decrease their value markedly. For many years I have lectured on organic gardening in the extension services master gardener classes. Part of the master gardener training includes interpreting soil test results. In the early 1980s when Oregon state government had more money all master gardener trainees were given a free soil test of their own garden. Inevitably an older gentleman would come up after my lecture and ask my interpretation of his puzzling soil test. Ladies, please excuse me. Lecturing in this area of women's lib I've broken my politically incorrect habit of saying the gardener he. But in this case it was always a man. An organic gardener who had been building up his soil for years. The average soils in our region test moderately to strongly acidic. Our low in nitrogen phosphorus calcium and magnesium. Quite adequate in potassium and have 3 to 4% organic matter. Mr. Organics soil test showed an organic matter content of 15 to 20% with more than adequate nitrogen and a pH of 7.2. However there was virtually no phosphorus calcium or magnesium and four times the amount of potassium that any farm agent would ever recommend. On the bottom of the test always written in red ink underlined with three exclamation points. No more wood ashes for five years. Because so many people in the maritime northwest heat with firewood the soil tester had mistakenly assumed that the soil became alkaline and developed such a potassium imbalance from heavy applications of wood ashes. This puzzled gardener couldn't grasp two things about his soil test report. One, he did not use wood ashes and had no wood stove. And two, although he had been building up his soil for six or seven years the garden did not grow as well as he had imagined it would. Perhaps you see why this questioner was always a man. Mr. Organic owned a pickup and loved to haul organic matter and to make and spread compost. His soil was full of worms and had a remarkably high humus level but still did not grow great crops. It was actually worse than he understood. Plants uptake as much potassium as there is available in the soil and concentrate that potassium in their top growth. So when vegetation is hauled in and composted or when animal manure is imported large quantities of potassium come along with them. As will be explained shortly vegetation from forested regions like western Oregon is even more potassium rich and contains less of other vital nutrients than vegetation from other areas. By covering his soil several inches thick with manure and compost every year he had totally saturated the earth with potassium. Its cation exchange capacity or in non-technical language the soil's ability to hold other nutrients had been overwhelmed with potassium and all phosphorus, calcium, magnesium and other nutrients had largely been washed away by rain. It was even worse than that. The nutritional quality of the vegetables grown on that superhumus-y soil was very, very low and would have been far higher had he used tiny amounts of compost and horror of all horrors, chemical fertilizer. Climate and nutritional quality of food. Over geologic time spans water passing through soil leeches or removes plant nutrients. In climates where there is barely enough rain to grow cereal crops soils retain their minerals and the food produced there tends to be highly nutritious. In verdant rainy climates the soil is leached of plant nutrients and the food grown there is much less nutritious. That's why the great healthy herds of animals were found on scrubby semi-arid grasslands like the American prairies. In comparison lush forests carry far lower quantities of animal biomass. Some plant nutrients are much more easily leached out than others. The first valuable mineral to go is calcium. Semi-arid soils usually still retain large quantities of calcium. The nutrient most resistant to leaching is potassium. Leached out forest soils usually still retain relatively large amounts of potassium. William Albrecht observed this data and connected with it a number of fairly obvious and vital changes in plant nutritional qualities that are caused by these differences in soil fertility. However obvious they may be Albrecht's work was not considered politically correct by his peers or the interest groups that supported agricultural research during the mid 20th century and his contributions have been largely ignored. Worse his ideas did not quite fit with the ideological preconceptions of J.I. Rodale so organic gardeners and farmers are also ignorant of Albrecht's wisdom. Albrecht would probably have approved of the following chart that expresses the essential qualities of dryland and humid soils. Soil mineral content by climate area. Plant nutrient nitrogen. Dryland prairie soil high. Humid forest soil low. Plant nutrient phosphorus. Dryland prairie soil high. Humid forest soil low. Plant nutrient potassium. Dryland prairie soil high. Humid forest soil moderately high. Plant nutrient calcium. Dryland prairie soil very high. Humid forest soil low. Plant nutrient pH. Dryland prairie soil neutral. Humid forest soil acid. Dryland soils contain far higher levels of all minerals than leached soils. But Albrecht speculated that the key difference between these soils is the ratio of calcium to potassium. In dryland soils there is much more calcium in the soil than there is potassium. While in wetter soils there is much more potassium than calcium. To test his theory he grew some soybeans in pots. One pot had soil with a high amount of calcium relative to the amount of potassium imitating dryland prairie soil. The other pot had just as much calcium but had more potassium giving it a ratio similar to a high quality farm soil in the eastern United States. Both soils grew good looking samples of soybean plants but when they were analyzed for nutritional content they proved to be quite different. Soil humid. Yield 17.8 grams. Calories high. Protein 13%. Calcium 0.27%. Phosphorus 0.14%. Potassium 2.15%. Soil dryland. Yield 14.7 grams. Calories medium. Protein 17%. Calcium 0.74%. Phosphorus 0.25%. Potassium 1.01%. The potassium fortified soil gave a 25% higher bulk yield but the soybeans contained 25% less protein. The consumer of those plants would have to burn off approximately 30% more carbohydrates to obtain the same amount of vital amino acids essential to all bodily functions. Wet soil plants also contain only one-third as much calcium an essential nutrient whose lack over several generations causes gradual reduction of skeletal size and dental deterioration. They also contain only half as much phosphorus another essential nutrient. Their oversupply of potassium is not needed. Humans eating balanced diets usually excrete large quantities of unnecessary potassium in their urine. Albrecht then analyzed dozens of samples of vegetation that came from both dryland soils and humid soils and noticed differences in them similar to the soybeans grown under controlled conditions. The next chart showing the average composition of plant vegetation from the two different regions is taken directly from Albrecht's research. The figures are averages of large numbers of plant samples including many different food crops from each climate. Average nutritional content by climate. Nutrient potassium. Dryland soil 2.44%. Humid soil 1.27%. Nutrient calcium. Dryland soil 1.92%. Humid soil 0.28%. Nutrient phosphorus. Dryland soil 0.78%. Humid soil 0.42%. Total mineral nutrition. Dryland soil 5.14%. Humid soil 1.97%. Ratio of potassium to calcium. Dryland soil 1.20% to 1%. Humid soil 4.50% to 1%. Analyzed as a whole these data tell us a great deal about how we should manage our soil to produce the most nutritious food and the judicious use of compost in the garden as well. I ask you to refer back to these three small charts as I point out a number of conclusions that can be drawn from them. The basic nutritional problem that all animals have is not about finding energy food but how to intake enough vitamins, minerals, and usable proteins. What limits our ability to intake nutrients is the amount of bulk we can process in the number of calories in the food. With cows, for example, bulk is the limiter. The cow will completely fill her digestive tract at all times and will process all the vegetation she can digest every day of her life. Her health depends on the amount of nutrition in that bulk. With humans our modern lifestyle limits most of us to consuming 1,500 to 1,800 calories a day. Our health depends on the amount of nutrients coming along with those calories. So I write the fundamental equation for human health as follows. Health equals nutrition in food divided by calories in that food. If the food that we eat contains all of the nutrients that food could possibly contain and in the right ratios then we will get sufficient nutrition while consuming the calories we need to supply energy. However, to the degree that our diet contains denatured food supplying too much energy we will be lacking nutrition and our bodies will suffer gradual degeneration. This is why foods such as sugar and fat are less healthful because they are concentrated sources of energy that contain little or no nutrition. Nutritionless food also contributes to hidden hungers since the organism craves something that is missing. The body overeats and it becomes fat and unhealthy. Albrecht's charts show us that food from dry climates tends to be high in proteins and essential minerals while simultaneously lower in calories. Food from wet climates tends to be higher in calories while much lower in protein and essential mineral nutrients. Albrecht's writing as well as those of Western Price and Sir Robert McCarrison listed in the bibliography examples showing how human health and longevity are directly associated with these same variations in climate, soil, and food nutrition. Albrecht pointed out a clear example of soil fertility causing health or sickness. In 1940 when America was preparing for World War II all eligible men were called in for a physical examination to determine fitness for military service. At that time Americans did not eat the same way we do now. Food was produced and it distributed locally. Bread was milled from local flour. Meat and milk came from local farmers. Vegetables and potatoes did not all come from California. Regional differences in soil fertility could be seen reflected in the health of people. Albrecht's state, Missouri, is divided into a number of distinct rainfall regions. The northwestern part is grassy prairie and receives much less moisture than the humid forested southeastern section. If soil tests were compared across a diagonal line drawn from the northwest to the southeast they would exactly mimic the climate-caused mineral profile differences Albrecht had identified. Not unexpectedly, 300 young men per 1,000 draftees were medically unfit for military service from the northwest part of Missouri while 400 per 1,000 were unfit from the southeastern part and 300 per 1,000 were unfit from the center of the state. Another interesting and rather frightening conclusion can be drawn from the second chart. Please notice that by increasing the amount of potassium in the potting soil Albrecht increased the overall yield by 25% while simultaneously lowering all of the other significant nutritional aspects. Most of this increase of yield was in the form of carbohydrates that in a food crops equates to calories. Agronomists also know that adding potassium fertilizer greatly and inexpensively increases yield. So American farm soils are routinely doused with potassium fertilizer, increasing bulk yield and profits without consideration for nutrition or for the ultimate costs in public health. Organic farmers often do not understand this aspect of plant nutrition either and may use organic forms of potassium to increase their yields and profits. Buying organically grown food is no guarantee that it contains the ultimate in nutrition. So if health comes from paying attention to the ratio of nutrition to calories in our food then as gardeners who are in charge of creating a significant amount of our own fodder we can take that equation a step further. Health equals nutrition divided by calories equals calcium divided by potassium. When we decide how to manage our gardens we can take steps to imitate dryland soils by keeping potassium levels lower while maintaining higher levels of calcium. Now take another close look at the third chart. Average vegetation from dryland soils contains slightly more potassium than calcium 1.2 to 1. While average vegetation from wetland soils contains many more times more potassium than calcium 4.5 to 1. When we import manure or vegetation into our garden or farm soils we are adding large quantities of potassium. Those of us living in rainy climates that were naturally forested have it much worse in this respect than those of us gardening on the prairies or growing irrigated gardens in desert climates because the very vegetation and manure we use to build up our gardens contains much more potassium while most of our soils already contain all we need and then some. It should be clear to you now why some organic gardeners receive the soil tests like the man at my lecture. Even the soil tester, although scientifically trained and university educated did not appreciate the actual source of the potassium overdose. The tester concluded it must have been wood ashes when actually the potassium came from organic matter itself. I conclude that organic matter is somewhat dangerous stuff whose use should be limited to the amount needed to maintain basic soil tilth and a healthy complex soil ecology. Fertilizing gardens organically Scientists analyzing the connections between soil fertility and the nutritional value of crops have repeatedly remarked that the best crops are grown with compost and fertilizer not fertilizer alone and not compost alone. The best place for gardeners to see these data is Werner Shupin's book, listed in the bibliography. But say the word fertilizer to an organic gardener and you will usually raise their hackles. Actually, there is no direct linkage of the words fertilizer and chemical. A fertilizer is any concentrated plant nutrient source that rapidly becomes available in the soil. In my opinion, chemicals are the poorest fertilizers. Organic fertilizers are far superior. The very first fertilizer sold widely in the industrial world was guano. It is the naturally sun-dried droppings of nesting seabirds that accumulates in thick layers on rocky islands off the coast of South America. Guano is a potent nutrient source similar to dried chicken manure containing large quantities of nitrogen, fair amounts of phosphorus, and smaller quantities of potassium. Guano is more potent than any other manure because seabirds eat ocean fish, a very high protein and highly mineralized food. Other potent organic fertilizers include seed meals, pure dried chicken manure, slaughterhouse wastes, dried kelp and other seaweeds, and fish meal. Composition of organic fertilizers. Material alfalfa meal, percent nitrogen 2.5, percent phosphorus 0.5, percent potassium 2.1. Material bone meal raw, percent nitrogen 3.5, percent phosphorus 21.0, percent potassium 0.2. Material bone meal steamed, percent nitrogen 2.0, percent phosphorus 21.0, percent potassium 0.2. Material chicken manure, pure fresh, percent nitrogen 2.6, percent phosphorus 1.25, percent potassium 0.75, material cottonseed meal, percent nitrogen 7.0, percent phosphorus 3.0, percent potassium 2.0, material blood meal, percent nitrogen 12.0, percent phosphorus 3.0, percent potassium blank, material fish meal, percent nitrogen 8.0, percent phosphorus 7.0, percent potassium blank, material green sand, percent nitrogen blank, percent phosphorus 1.5, percent potassium 7.0, material hoof and horn, percent nitrogen 12.5, percent phosphorus 2.0, percent potassium blank, material kelp meal, percent nitrogen 1.5, percent phosphorus 0.75, percent potassium 4.9, material peanut meal, percent nitrogen 3.6, percent phosphorus 0.7, percent potassium 0.5, material tankage, percent nitrogen 11.0, percent phosphorus 5.0, percent potassium blank. Growing most types of vegetables requires building a level of soil fertility that is much higher than required by field crops like cereals, soybeans, cotton, and sunflowers. Field crops can be acceptably productive on ordinary soils without fertilization. However, because we have managed our farm soils as depreciating industrial assets, rather than as relatively immortal living bodies, their ability to deliver plant nutrients has declined and the average farmer usually must add additional nutrients in the form of concentrated, readily releasing fertilizers if they are going to grow a profitable crop. Vegetables are much more demanding than field crops. They have long been adapted to growing on potent composts or strong manures like fresh horse manure or chicken manure. Planted and nourished like wheat, most would refuse to grow, or if they did survive in a wheat field, vegetables would not produce the succulent tender parts we consider valuable. Building higher than normal levels of plant nutrients can be done with large additions of potent compost and manure. In semi-arid parts of the country where vegetation holds a beneficial ratio of calcium to potassium, food grown that way will be quite nutritious. In areas of heavier rainfall, increasing soil fertility to vegetable levels is accomplished better with fertilizers. The data in the previous section gives strong reasons for many gardeners to limit the addition of organic matter in soil to a level that maintains a healthy soil ecology and acceptable tilth. Instead of supplementing compost with low-quality chemical fertilizers, I recommend making and using a complete organic fertilizer mix to increase mineral fertility. Making and using Complete Organic Fertilizer The basic ingredients used for making balanced organic fertilizers can vary, and what you decide on will largely depend on where you live. Seed meal usually forms the body of the blend. Seed meals are high in nitrogen and moderately rich in phosphorus because plants concentrate most of the phosphorus they collect during their entire growth cycle into their seeds to serve to give the next generation a strong start. Seed meals contain low but more than adequate amounts of potassium. The first mineral to be removed by leaching is calcium. Adding lime can make all the difference in wet soils. Dolomite lime also adds magnesium and is the preferable form of lime to use in a fertilizer blend on most soils. Gypsum could be substituted for lime in arid areas where the soils are naturally alkaline but still may benefit from additional calcium. Kelp meal contains valuable trace minerals. If you don't have enough money, first I'd eliminate the kelp meal, then the phosphate source. All ingredients going into this formula are measured by volume and the measurements can be very rough by sack, by scoop, or by coffee can. You can keep the ingredients separated and mix fertilizer by the bucketful as needed or you can dump the contents of half a dozen assorted sacks out on a concrete sidewalk or driveway with them with a shovel and then store the mixture in garbage cans or even in the original sacks the ingredients came in. This is my formula. Four parts by volume. Any seed meal such as cotton seed meal, soybean meal, sunflower meal, canola meal, linseed meal, safflower, peanut meal, or coconut meal. Gardeners with deep pocketbooks and insensitive nose also use fish meal. Gardeners without vegetarian scruples may use meat meal, tankage, leather dust, feather meal, or other slaughterhouse waste. One part by volume, bone meal, or rock phosphate. One part by volume, lime, preferably dolomite, on most soils. Soils derived from serpentine rock contain almost toxic levels of magnesium and should not receive dolomite. Alkaline soils may still benefit from additional calcium and should get gypsum instead of ordinary lime. Half part by volume, kelp meal, or other dried seaweed. To use this fertilizer broadcast and work in about one gallon per each 100 square feet of growing bed or 50 feet of row. This is enough for all low demand soils like carrots, beans, and peas. For more needy species blend an additional handful or two into about a gallon of soil below the transplants or in the hill. If planting in rows, cut a deep furrow, sprinkle in about one pint of fertilizer per 10 to 15 row feet. Cover the fertilizer with soil and then cut another furrow to sow the seeds in about two inches away. Locating concentrations of nutrition close to seeds or seedlings is called banding. I have a thick file of letters thanking me for suggesting the use of this fertilizer blend. If you've been building up your soil for years, or if your vegetables never seem to grow as big or lustily as you imagine they should, I strongly suggest you experiment with a small batch of this mixture. Wouldn't you like heads of broccoli that were used in diameter or zucchini plants that didn't quit yielding? End of Chapter 8 Chapter 9 Of Organic Gardeners Composting This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information or to volunteer, please visit LibriVox.org Read by Betsy Bush March 2009 Organic Gardeners Composting by Steve Solomon Chapter 9 Making Superior Compost The potency of composts can vary greatly. Most municipal solid waste compost has a high carbon-to-nitrogen ratio, and when tilled into soil temporarily provokes the opposite of a good growth response until soil animals and microorganisms consume most of the undigested paper. But if low grade compost is used as a surface mulch on ornamentals the results are usually quite satisfactory even if unspectacular. If the aim of your composting is to conveniently dispose of yard waste and kitchen garbage the information in the first half of the book is all you need to know. If you need compost to make something that dependably grows plants like it was fertilizer then this chapter is for you. A Little History Before the 20th century the fertilizers market gardeners used were potent manures and composts. The vegetable gardens of country folk also received the best manures and composts available while the field crops got the rest. So I've learned a great deal from old farming and market gardening literature about using animal manures. In previous centuries farmers classified manures by type and purity. There was long and short manure and then there was the supreme plant growth stimulant, chicken manure. Chicken manure was always highly prized but usually in short supply because pre-industrial fowl weren't caged in factories or permanently locked in hen houses and fed scientifically formulated mixes. The chicken breed of that era was usually some type of bantam, half-wild, broody protective of chicks full of foraging. A typical pre-1900s small-scale chicken management system was to allow the flock free access to hunt their own meals in the barnyard and orchard, luring them into the coop at dusk with a bit of grain where they were protected from predators while sleeping helplessly. Some manure was collected from the hen house but most of it was dropped where it could not be gathered. The daily egg hunt was worth it because before the era of pesticides having chickens range through the orchard greatly reduced problems with insects in fruit. The high potency of chicken manure derives from the chickens low C to N diet. Worms, insects, tender shoots of new grass and other protein asious young greens and seeds. 20th century chickens living in egg and meat factories must still be fed low C to N foods primarily grains and their manure is still potent. But anyone who has savored real free range eggs with deep orange yolks from chickens on a proper diet cannot be happy with what passes for eggs these days. Fertilizing with pure chicken manure is not very different than using ground, cereal grains or seed meals. It is so concentrated that it might burn plant leaves like chemical fertilizer does and must be applied sparingly to soil. It provides a marked and vigorous growth response. Two or three gallons of dry, pure fresh chicken manure are sufficient nutrition to grow about 100 square feet of vegetables in raised beds to the maximum. Exclusively incorporating pure chicken manure into a vegetable garden also results in rapid humus loss just as though chemical fertilizers were used. Any fertilizing substance with a C to N below that humus, be it a chemical or a natural substance, accelerates the decline in soil organic matter. That is because nitrate nitrogen, the key to constructing all protein, is usually the main factor limiting the population of soil microorganisms. When the nitrate level of soil is significantly increased microbopopulations increase proportionately and proceeds to eat organic matter at an accelerated rate. That is why small amounts of chemical fertilizer applied to soil that still contains a reasonable amount of humus has such a powerful effect. Not only does the fertilizer itself stimulate the growth of plants but fertilizer increases the microbial population. More microbes accelerate the breakdown of humus and even more plant nutrients are released as organic matter decays. And that is why holistic farmers and gardeners mistakenly criticize chemical fertilizers as being directly destructive of soil microbes. Actually, all fertilizers, chemical or organic indirectly harm soil life. First increasing their populations to unsustainable levels that drop off markedly once enough organic matter has been eaten. Unless, of course, the organic matter is replaced. Chicken manure compost is another matter. Mix the pure manure with straw, dust or other bedding, compost it and, depending on the amount and quantity of bedding used and the time allowed for decomposition to occur, the resultant C to N will be around 12 to 1 or above. Any ripened compost around 12 to 1 still will grow plants beautifully. Performance drops off as the C to N increases. Since chicken manure was scarce most pre-20th century market gardeners depended on seemingly limited supplies of short manure generally from horses. The difference between the long and the short manure was bedding. Long manure contained straw from the stall while short manure was pure street sweepings without adulterance. Hopefully the straw portion of long manure had absorbed a quantity of urine. People of that era knew the fine points of hay quality as well as people today know their gasoline. Horses expected to do a day's bed on grass or grass clover mixes that had been cut and dried while they still had a high protein content. Leafy hay was highly prized while hay that upon close inspection revealed lots of stems and seed heads would be rejected by a smart buyer. The working horse's diet was supplemented with a daily ration of grain. Consequently uncomposted fresh short manure probably started out with a C to N around 15 to 1. However, don't count on anything that good from horses these days. Most horses aren't worked daily so their fodder is often poor. Judging from the stemmy cut too late grass hay our local horses have to try to survive on. If I could find bedding free horse manure it would probably have a C to N more like 20 to 1. Maneur from physically fit thoroughbred raised horses is probably excellent. Using fresh horse manure in soil gave many vegetables a harsh flavor so it was first composted by mixing in some soil, a good idea because otherwise a great deal of ammonia would escape the heap. Market gardeners raising highly demanding crops like cauliflower and celery amended composted short manure by the inches thick layer. Lesser nutrient demanding crops like snap beans, lettuce and roots followed these intensely fertilized vegetables without further compost. Long manures containing lots of straw were considered useful only for field crops or root vegetables. Wise farmers conserved the nitrogen and promptly composted long manures. After heating and turning the resulting C to N would probably be in a little below 20 to 1. After tilling it in a short period of time was allowed while the soil digested this compost before sowing seeds. Lazy farmers spread raw manure load by load as it came from the barn and tilled it in once the entire field was covered. This easy method allows much nitrogen to escape as ammonia while the manure dries in the sun. Commercial vegetable growers had little use for long manure. One point of this brief history lesson is G-I-G-O garbage in garbage out. The finished compost tends to have a C to N that is related to the ingredients that built the heap. Growers of vegetables will wisely take note. Anyone interested in learning more about pre-industrial market gardening might ask their librarians to seek out a book called French Gardening by Thomas Smith, published in London about 1905. This fascinating little book was written to encourage British market gardeners to imitate the Parisian Mersiere who skillfully earned top returns growing out season produce on intensive double dug raised beds, often under glass hot or cold frames. Our trendy American biodynamic French intensive gurus obtained their inspiration from England through this tradition. Curing the heap. The easiest and most surefire improver of compost quality is time. Making a heap with predominantly low C to N materials inevitably results in potent compost if nitrogen loss is kept to a minimum. But the C to N of almost any compost heap, even one starting with a high C to N, will eventually lower itself. The key word here is, eventually. The most dramatic decomposition occurs during the first few turns when the heap is hot. Many people, including writers of garden books, mistakenly think that the composting ends when the pile cools and the material no longer what made up the heap. This is not true. As long as a compost heap is kept moist and is turned occasionally it will continue to decompose. Curing or ripening are terms used to describe what occurs once heating is over. A different ecology of microorganisms predominates while a heap is ripening. If the heap contains 5-10% soil, is kept moist, is turned occasionally so it stays aerobic and has a complete mineral balance considerable bacterial nitrogen fixation may occur. Most gardeners are familiar with the microbes that nodulate the roots of legumes. Called rhizobia, these bacteria are capable of fixing large quantities of nitrate nitrogen in a short amount of time. Rhizobia tend to be inactive during hot weather because the soil itself is supplying nitrates from the breakdown of organic matter. Interplanting inter-legume crops like cow peas and snap beans tend to be net consumers of nitrates not makers of more nitrates than they can use. Consider this when you read in carefully researched garden books and articles about the advantages of interplanting legumes with other crops because they supposedly generate nitrates that help their companions. But during spring or fall when lowered soil temperatures retard decomposition, rhizobia can manufacture from 80 to 200 pounds of nitrates per acre. Peas, clovers, alfalfa, vetches, and fava beans can all make significant contributions of nitrate nitrogen and smart farmers prefer to grow their nitrogen by green maneuvering legumes. Wise farmers also know that this nitrate, though produced in root nodules, is used by legumes to grow leaf and stem. So the entire legume must be tilled in if any plant nitrogen gain is to be realized. This wise practice simultaneously increases organic matter. Rhizobia are not capable of being active in compost piles, but another class of microbes is called azobacteria, these free living soil dwellers also make nitrate nitrogen. Their contribution is not potentially as great as rhizobia, but no special provision must be made to encourage azobacteria rather than maintaining a decent level of humus for them to eat, a balanced mineral supply that includes adequate calcium and a soil pH between 5.75 and 7.25. A high yielding crop of wheat needs 60 to 80 pounds of nitrates per acre. Corn and most vegetables can use twice that amount. Azobacteria can make enough for wheat, though an average nitrate contribution under good soil conditions might be more like 30 to 50 pounds per year. Once a compost heap has cooled azobacteria will proliferate and begin to manufacture significant amounts of nitrates steadily lowering the C to N and carbon never stops being digested further dropping the C to N. The rapid phase of composting may be over in a few months, but ripening can be allowed to go on for many more months if necessary. Feeding unripened compost to worms is perhaps the quickest way to lower C to N and make a potent soil amendment. Once the high heat of decomposition has passed and the heap is cooling it is commonly invaded by red worms, the same species used for vermicomposting kitchen garbage. These worms would not be able to eat the high C to N material that went into a heap, but after heating the average C to N has probably dropped enough to be suitable for them. The municipal composting operation at Fallbrook, California makes clever use of this method to produce a smaller amount of high grade product out of a larger quantity of low grade ingredients. Mixtures of sewage sludge and municipal solid waste are first composted and after cooling the half done high C to N compost is shallowly spread out over crude worm beds and kept moist. More crude compost is added as the worms consume the waste, much like a household worm box. The worm beds gradually rise. The lower portion of these mounds is pure castings while the worm activity stays closer to the surface where food is available. When the beds have grown to about 3 feet tall, the surface few inches containing worms and undigested food are scraped off and used to form new vermicomposting beds. The castings below are considered finished compost. By laboratory analysis the castings contain 3 or 4 times as much nitrogen as the crude compost being fed to the worms. The marketplace gives an excellent indicator of the difference between their crude compost and the worm casts even though Fallbrook is surrounded by large acreages devoted to citrus orchards and row crop vegetables, the municipality has a difficult time disposing of the crude product but their vermicompost is in strong demand. Sir Albert Howard's indoor method. 19th century farmers and market gardeners had much practical knowledge about using manures and making compost that worked like fertilizers but little was known about the actual microbial process of composting until our century. As information became available about compost ecology, one brilliant individual, Sir Albert Howard incorporated the new science of soil microbiology into his composting and by patient experiment learned how to make superior compost. During the 1920s Albert Howard was in charge of a government research farm at Indore India. At heart a Peace Corps volunteer he made indoor operate like a very representative Indian farm growing all the main staples of the local agriculture cotton sugarcane and cereals. The farm was powered by the same work oxen used by the surrounding farmers. It would have been easy for Howard to demonstrate better yields through high technology by buying chemical fertilizers or using seed meal wastes from oil extraction, using tractors and growing new high yielding varieties that could make use of more intense soil nutrition. But these inputs were not affordable to the average Indian farmer and Howard's purpose was to offer genuine help to his neighbors by demonstrating methods they could easily and use. In the beginning of his work at Indore Howard observed that the district's soils were basically fertile but low in organic matter and nitrogen. This deficiency seemed to be due to traditionally wasteful practices concerning manures and agricultural residues. So Howard began developing methods to compost the waste products of agriculture making enough high quality fertilizer to supply the entire farm. Soon Indore research farm was enjoying record yields without having insect or disease problems and without buying fertilizer or commercial seed. More significantly the work animals fed exclusively on fodder from Indore's humus rich soil became invulnerable to cattle diseases. Their shining health and fine condition became the envy of the district. Most significant Howard contended that his method not only conserved the nitrogen in cattle and crop waste, not only conserved the organic matter the land produced but also raised the processes of the entire operation to an ecological climate of maximized health and production. Conserving the manure and composting the crop waste allowed him to increase the soil's organic matter which increased the soil's release of nutrients from rock particles that further increased the production of biomass which allowed him to make even more compost and so on. What I have just described is not surprising. It is merely a variation on good farming that some humans have known about for millennia. What was truly revolutionary was Howard's contention about increasing net nitrates. With gentle understatement Howard asserted that his compost was genuinely superior to anything ever known before. Indore compost had these advantages. No nitrogen or organic matter was lost from the farm through mishandling of agricultural waste. The humus level of the farm's soil increased to a maximum sustainable level. And the amount of nitrate nitrogen in the finished compost was higher than the total amount of nitrogen contained in the materials that formed the heap. Indore compost resulted in a net gain of nitrate nitrogen. The compost factory was also a biological nitrate factory. Howard published details of the Indore method in 1931 in a slim book called The Waste Products of Agriculture. The widely read book brought him invitations to visit plantations throughout the British Empire. It prompted farmers worldwide to make compost by the Indore method. Travel, contacts and new awareness of the problems of European agriculture were responsible for Howard's decision to create an organic farming and gardening movement. Howard repeatedly warned in The Waste Products of Agriculture that if the underlying fundamentals of his process were altered superior results would not occur. This was his viewpoint in 1931. However, humans being what we are it does not seem possible for good technology to be broadcast without each user trying to improve and adapt it to their own situation and understanding. By 1940 the term Indore compost had become a generic term for any kind of compost made in a heap without the use of chemicals. Much as rototiller has come to mean any motor driven rotary tiller. Howard's 1931 concerns were correct. Almost all alterations of the original Indore system lessened its value. But Howard of 1941 did not resist this dilutive trend because in an era of chemical farming any compost was better than no compost. Any return of humus better than none. Still, I think it is useful to go back to the Indore research farm of the 1920s and to study closely how Albert Howard once made the world's finest compost and to encounter this great man's thoughts before he became a crusading ideologue dead set against any use of agricultural chemicals. A great many valuable lessons are still contained in the waste products of agriculture. Unfortunately, even though many organic gardeners are familiar with the latter works of Sir Albert Howard the reformer, Albert Howard the scientist and researcher who wrote this book is virtually unknown today. At Indore all available vegetable material was composted including manure and bedding straw from the cattle shed unconsumed crop residues fallen leaves and other forest wastes, weeds and green manures grown specifically for compost making all of the urine from the cattle shed in the form of urine earth and all wood ashes from any source on the farm were also included. Being in the tropics compost making went on year round of the result Howard stated that the product is a finely divided leaf mold of high nitrifying power ready for immediate use without temporarily inhibiting plant growth. The fine state of division enables the compost to be readily incorporated and to exert its maximum influence on a very large area of the internal surface of the soil. Howard stressed that for the indoor method to work reliably the carbon to nitrogen ratio of the material going into the heap must always be in the same range. Every time a heap was built the same assortment of crop wastes were mixed with the same quantities of fresh manure and urine earth as with my bread baking analogy Howard ensured repeatability of ingredients. Any hard woody materials Howard called them refractory must be thoroughly broken up before composting otherwise the fermentation would not be vigorous rapid and uniform throughout the process. This mechanical softening up was cleverly accomplished without power equipment by spreading tough crop wastes like cereal straw or pigeon pea and cotton stalks out over the farm roads allowing cartwheels and oxen hooves and foot traffic to break them up. Decomposition must be rapid and aerobic but not too aerobic and not too hot. Quite intentionally indoor compost piles were not allowed to reach the highest temperatures that are possible. During the first heating cycle peak temperatures were about 140°C after two weeks when the first turn was made temperatures had dropped to about 125°C and gradually declined from there. Howard cleverly restricted the air supply and thermal mass so as to bank the fires of decomposition. This moderation was his key to preventing loss of nitrogen. Provisions were made to water the heaps as necessary to turn them several times and to use a novel system of mass inoculation with the proper fungi and bacteria. I'll shortly discuss each of these subjects in detail. Howard was pleased that there was no need to accept nitrogen loss at any stage and that the reverse should happen. Once the C to N had dropped sufficiently the material was promptly incorporated into the soil where nitrate nitrogen will be best preserved. But the soil is not capable of doing any jobs at once. It can't digest crude organic matter and simultaneously nitrify humus. So compost must be finished and completely ripe when it was tilled in so that there must be no serious competition between the last stages of decay of the compost and the work of the soil in growing the crop. This is accomplished by carrying the manufacture of humus up to the point when nitrification is about to begin. In this way the Chinese principle of dividing the growing of a crop into two separate processes. One, the preparation of the food materials outside the field, and two the actual growing of the crop can be introduced into general agricultural practice. And because he actually lived on a farm Howard especially emphasized that composting must be sanitary and odorless and that flies must not be allowed to breed in the compost or around the work cattle. Country life can be quite idyllic without flies. The indoor compost factory. At indoor Howard built a covered open-sided compost making factory that sheltered shallow pits each 30 feet long by 14 feet wide by 2 feet deep with sloping sides. The pits were sufficiently spaced to allow loaded carts to have access to all sides of any of them and a system of pipes brought water near every one. The materials to be composted were all stored adjacent to the factory. Howard's work oxen were conveniently housed in the next building. Soil and urine earth. Howard had been raised on an English farm and from childhood he had learned the ways of work animals and how to make them comfortable. So for the ease of their feet the cattle shed and its attached roofed loafing pen had earth floors. All soil removed from the silage pits, dusty sweepings from the threshing floors and silt from the irrigation ditches were stored near the cattle shed and used to absorb urine from the work cattle. This soil was spread about six inches deep in the cattle stalls and loafing pens. About three times a year it was scraped up and replaced with fresh soil. Urine saturated earth then was dried and stored in a special covered enclosure to be used for making compost. The presence of this soil in the heap was essential. First the black soil of indoor was well supplied with calcium, magnesium and other plant nutrients. These basic elements prevented the heaps from becoming overly acid. Additionally the clay in the soil was uniquely incorporated into the heap so that it coated everything. Clay has a strong ability to absorb ammonia preventing nitrogen loss. A clay coating also holds moisture. Without soil and even and vigorous mycelial growth is never quickly obtained. Howard said the fungi are the storm troops of the composting process and must be furnished with all the armament they need. Crop wastes Crop wastes were protected from moisture stored dry under cover near the compost factory. Green materials were first withered in the sun for a few days before storage. Refractory materials were spread on the farm's roads and crushed by foot traffic in cartwheels before stacking. All these forms of vegetation were thinly layered as they were received so that the dry storage stacks became thoroughly mixed. Care was taken to preserve the mixing by cutting vertical slices out of the stacks when vegetation was taken to the compost pits. Howard said the average C to N of this mixed vegetation was about one. Every compost heap made year round was built with this complex assortment of vegetation having the same properties and the same C to N. Special preliminary treatment was given to hard woody materials like sugarcane, millet stumps, wood shavings, and waste paper. These were first dumped into an empty compost pit mixed with a little soil and kept moist until they softened. Or they might be soaked in water for a few days and then used to the bedding under the work cattle. Great care was taken when handling the cattle's bedding to ensure that no flies would breed in it. Maneur Though crop wastes and urine earth could be stored dry for later use, manure, the key ingredient of indoor compost had to be used fresh. Fresh cow dung contains bacteria from the cow's rumin that is essential to the rapid decomposition of cellulose and other dry vegetation. Without their abundant presence composting would not begin as rapidly nor proceed as surely. Charging the compost pits Every effort was made to fill a pit to the brim within one week. If there wasn't enough material to fill an entire pit within one week then a portion of one pit would be filled to the top. To preserve good aeration every effort was made to avoid material while filling the pit. As mixtures of manure and bedding were brought out from the cattle shed they were thinly layered atop thin layers of mixed vegetation brought in from the dried reserves heaped up adjacent to the compost factory. Each layer was thoroughly wet down with a clay slurry made of three ingredients water, urine earth, and actively decomposing material from an adjacent compost pit that had been filled about two weeks earlier. This ensured that every particle within the heap was moist and was coated with nitrogen rich soil and the microorganisms of decomposition. Today we would call this practice mass inoculation. Pits vs. Heaps India has two primary seasons. Most of the year is hot and dry while the monsoon rains come from June through September. During the monsoon so much water falls so continuously that the earth becomes completely saturated even though the pits were under a roof they would fill with water during this period. So in the monsoon compost was made in low heaps atop the ground. Compared to the huge pits their dimensions were smaller than you would expect. Seven by seven feet at the top eight by eight feet at the base and no more than two feet high. When the rains started any compost being completed in pits was transferred to above ground heaps when it was turned. Howard was accomplishing several things by using shallow pits or low but very broad heaps. One, thermal masses were reduced so temperatures could not reach the ultimate extremes possible while composting. The pits were better than heaps because air flow was further reduced slowing down the fermentation while their slowness still permitted efficient aeration. There were enough covered pits to start a new heap every week. Temperature range in normal pit age three days temperature 63 degrees Celsius four days 60 degrees Celsius six days 58 degrees Celsius 11 days 55 degrees Celsius 12 days 13 days 49 degrees Celsius 14 days 49 degrees Celsius first turn 18 days 49 degrees Celsius 20 days 51 degrees Celsius 22 days 48 degrees Celsius 24 days 47 degrees Celsius 29 days second turn 37 days 49 degrees Celsius 38 days 45 degrees Celsius 40 days 40 degrees Celsius 43 days 39 degrees Celsius 57 days 39 degrees Celsius third turn 61 days 41 degrees Celsius 76 days 38 degrees Celsius 82 days 36 degrees Celsius 90 days 33 degrees Celsius period in days for each fall of 5 degrees Celsius temperature range 65 degrees to 60 degrees number of days four 60 degrees to 55 degrees 7 days 1 day 50 degrees to 45 degrees 25 days 45 degrees to 40 degrees 2 days 40 degrees to 35 degrees 44 days 35 degrees to 30 degrees 14 days 97 days turning turning the compost was done 3 times to ensure uniform decomposition to restore moisture and air and to supply massive quantities of those types of microbes needed to take the composting process to its next stage the first turn was at about 16 days a second mass inoculation equivalent to a full wheel barrel's full of 30 day old composting material was taken from an adjacent pit and spread evenly over the surface of the pit being turned then one half of the pit was dug out with a manure fork half a small quantity of water was added if needed to maintain moisture now the compost occupied half the pit a space about 15 by 14 and was about 3 feet high rising out of the earth about 1 foot during the monsoons when heaps were used the above ground piles were also mass inoculated and then turned so as to completely mix the material and as we do today we have the material in the core and vice versa one month after starting or about two weeks after the first turn the pit or heap would be turned again more water would be added this time the entire mass would be forked over from one half the pit to the other and every effort would be made to fluff up the material while thoroughly mixing it and a few loads of material were removed to inoculate a 15 day old pit another month would pass or about two months after starting and for the third time the compost would be turned and then allowed to ripen this time the material is brought out of the pit and piled atop the earth so as to increase aeration at this late stage there would be no danger of encouraging high temperatures but the increased oxygen facilitated in nitrogen fixation the contents of several pits might be combined to form a heap no larger than 10 by 10 at the base 9 by 9 on top and no more than 3.5 feet high again more water might be added ripening would take about one month Howard's measurements showed that after a month's maturation the finished compost should be used without delay or precious nitrogen would be lost however keep in mind when considering this brief ripening period that the heap was already as potent as it could become Howard's problem was not further improving the C to N it was conservation of nitrogen the superior value of indoor compost Howard said that finished indoor compost was twice as rich in nitrogen as ordinary farm yard manure and that his target was compost with a C to N of 10 to 1 since it was long manure he was referring to let's assume that the C to N of a new heap started at 5 to 1 the C to N of vegetation collected during the year is highly valuable young grasses and legumes are very high in nitrogen while dried straw from manure plants has a very high C to N if compost is made catch as catch can by using materials as they come available then results will be highly erratic Howard had attempted to make composts of single vegetable materials like nitrogen residues cane trash, weeds fresh wet sweet clover or the waste of field peas these experiments were always unsatisfactory so Howard wisely mixed his vegetation first withering and drying green materials by spreading them thinly in the sun to prevent their premature decomposition and then taking great care to preserve a uniform mixture of vegetation types when charging his compost pits this strategy can be located by the home gardener Howard was surprised to discover that he could compost all the crop waste he had available with only half the urine earth and about one quarter of the oxa manure he had available but fresh manure and urine earth were essential during the 1920s a patented process for making compost with a chemical fertilizer called ADCO was in vogue and Howard tried it of using chemicals he said the weak point of ADCO is that it does nothing to overcome one of the great difficulties in composting mainly of the absorption of moisture in the early stages in hot weather in India the ADCO pits lose moisture so rapidly that the fermentation stops the temperature becomes uneven and then falls when however urine earth and cow dung are used the residues become covered with a thin colloidal film which not only contains moisture but also contains combined nitrogen and minerals required by the fungi this film enables the moisture to penetrate the mass and helps the fungi to establish themselves another disadvantage of ADCO is that when this material is used according to the directions the carbon nitrogen ratio of the final product is narrower than the ideal 10 to 1 nitrogen is almost certain to be lost before the crop can make use of it fresh cow manure contains digestive enzymes and living bacteria that specialize in cellulose decomposition having a regular supply of this material helped initiate decomposition without delay contributing large quantities of actively growing microorganisms through mass inoculation with material from a 2 week old pile also helped the second mass inoculation at 2 weeks with material from a 2 month old heap provided a large supply of the type of organisms required when the heap began cooling city gardeners without access to fresh manure may compensate for this lack by imitating Howard's mass inoculation technique starting smaller amounts of compost in a series of bins and mixing into each bin a bit of material from the one further along at each turning the passive backyard composting container automatically duplicates this advantage it simultaneously contains all decomposition stages and inoculates the material above by contact with more decomposed material below using prepared inoculants in a continuous composting bin is unnecessary city gardeners cannot readily obtain urine earth nor are American country gardeners with livestock likely to be willing to do so much work remember that Howard used urine earth for three reasons one it contained a great deal of nitrogen and improved the starting seed second it is thrifty over half the nutrient content of the food passing through the cattle is discharged in the urine but equally important soil itself was beneficial to the process of this Howard said where there may be insufficient dung and urine earth for converting large quantities of vegetable waste which are available the shortage may be made up by the use of nitrate of soda if such artificial employed it will be a great advantage to make use of soil I'm sure he would have made very similar comments about adding soil when using chicken manure or organic concentrates like seed meals as cattle manure substitutes control of the air supply is the most difficult part of composting first the process must stay aerobic that is one reason that single material heaps fail because they tend to pack too tightly to facilitate air exchange the pits or heaps were never more than two feet deep where air was insufficient though still aerobic decay is retarded but worse a process called denitrification occurs in which nitrates and ammonia are biologically broken down into gases and permanently lost too much manure and urine earth can also interfere with aeration by making the heap too heavy to accomplish anaerobic conditions the chart illustrates denitrification caused by insufficient aeration compared to turning the composting process into a biological nitrate factory with optimum aeration making indoor compost in deep and shallow pits amount of material pounds wet in pit at start pit four feet deep 4500 pit two feet deep 4514 total nitrogen pound at start pit four feet deep 31.25 pit two feet deep 29.12 total nitrogen at end pit four feet deep 29.49 pit two feet deep 32.36 loss or gain of nitrogen pit four feet deep negative 1.76 pit two feet deep plus 3.24 percentage loss or gain of nitrogen pit four feet deep negative 6.1% pit two feet deep plus 11.1% finally modern gardeners might consider limiting temperature during composting India is a very warm climate with balmy nights most of the year heaps two or three feet high will achieve an initial temperature of about 145 degree the purchase of a thermometer with a long probe and a little experimentation will show you the dimensions that will more or less duplicate Howard's temperature regimes in your climate with your materials inoculants Howard's technique of mass inoculation with large amounts of biologically active material from older compost heaps speeds and directs decomposition it supplies large numbers of the most useful types of microorganisms so they dominate the heaps ecology before other less desirable types can establish significant populations I can't imagine how selling mass inoculants could be turned into a business but just imagine that seeding a new heap with tiny amounts of superior microorganisms could speed initial decomposition and result in a much better product that could be a business such an approach is not without precedent brewers, winters, and bread makers all do that and ever since composting became interesting to 20th century farmers and gardeners entrepreneurs have been concocting compost starters that are intended to be added by the ounces to the cubic yard unlike the mass inoculation used at indoor these inoculants are a tiny population compared to the microorganisms already present in any heap in that respect inoculating compost is very different than beer, wine, or bread with these food products there are few or no microorganisms at the start the inoculant, small as it might be still introduces millions of times more desirable organisms than those wild types that might already be present but the materials being assembled into a new compost heap are already loaded with microorganism as when making sauerkraut what is needed is present at the start a small packet of inoculant is not likely to introduce what is not present anyway and the complex ecology of decomposition will go through its inevitable changes as the microorganisms respond to variations in temperature aeration, pH, etc this is one area of controversy where I am comfortable seeking the advice of an expert in this case the authority is Clarence Goluk who personally researched and developed UC fast composting in the early 1950s and who has been developing municipal composting systems ever since the bibliography of this book lists two useful words by Goluk Goluk has run comparison tests of compost starters of all sorts because in his business entrepreneurs are constantly attempting to sell inoculants to municipal composting operations of these vendors Goluk says with thinly disguised contempt most starter entrepreneurs include enzymes when listing the ingredients of their products the background for this inclusion parallels the introduction of purportedly advanced versions of starters i.e. advanced in terms of increased capacity utility and versatility thus in the early 1950s when I made my appearance on the compost scene starters were primarily microbial and references to identities of constituent microbes were very vague references to enzymes were extremely few and far between as early pioneer researchers began to issue formal and informal reports on microbial groups e.g. actinomycetes observed by them they also began to conjecture on the roles of those microbial groups in the compost process the conjectures frequently were accompanied by surmises about the part played by enzymes coincidentally vendors of starters in vogue at the time began to claim that their products included the newly reported microbial groups as well as an array of enzymes for some reason hormones were attracting attention at the time so most starters were supposedly laced with hormones in time hormones began to disappear from the picture enzymes were given a billing parallel to that accorded to the microbial component Goluk has worked out methods of testing starters that eliminates any random effects and conclusively demonstrates the results inevitably and repeatedly he found that there was no difference between using a starter and not using one and he says although anecdotal accounts of success due to the use of particular inoculum are not unusual in the popular media we have yet to come across unqualified accounts of successes in the referred scientific and technical literature I use a variation of mass inoculation when making compost while building a new heap I periodically scrape up and toss in a few shovels of compost and soil from where the previous pile was made frankly, if I did not do this I don't think the result would be any worse