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Return On Investment
In article ,
"David Hare-Scott" wrote: Pavel314 wrote: Yesterday evening I spread two 28' x 28' bird nets over my raspberry patch. There were only a few berries last year but this year it looks like I'll get about a quart. During the process, I realized that I was struggling out in the heat to install $50 worth of bird netting to save about $5 worth of berries. Not a great one-time investment, but next year the patch should really start bearing and the netting will be well worth the investment. Paul Small scale growing has problems of cost effectiveness when compared to supermarket prices, especially when you are starting out. If you factor in the other benefits and pleasures that eating your own produce provides it is much more worth it. If you can increase your scale moderately so that you multiply your production using the same fixed overheads and if you can learn to recycle and reuse instead of purchasing your inputs the financial balance comes back into your favour. The way to do this is to provide for more than one family (unless you have a large one already), to learn to preserve your abundant crops and to sell or exchange the rest locally. This is probably not possible if all you have is a balcony but if you have 50 sq metres of soil in a sunny spot it is. If in doubt give it away. I often give surplus veges to neighbours without expecting anything in return, however things come back to you. Last year one fixed my car (which would have cost several hundred dollars) and refused to take any money. David Truly, what is the price of community? ----- The Omnivore's Dilemma: A Natural History of Four Meals by Michael Pollan http://www.amazon.com/Omnivores-Dile...ls/dp/01430385 83/ref=pd_bbs_1?ie=UTF8&s=books&qid=1206815576&sr=1-1 p.79 Some intriguing recent research suggests otherwise. A study by University of California-Davis researchers published in the Journal of Agriculture and Food Chemistry in 2003 described an experiment in which identical varieties of corn, strawberries, and blackberries grown in neighboring plots using different methods (including organically and conventionally) were compared for levels of vitamins and polyphenols. Polyphenols are a group of secondary metabolites manufactured by plants that we've recently learned play an important role in human health and nutrition. Many are potent antioxidants; some play a role in preventing or fighting cancer; others exhibit antimicrobial properties. The Davis researchers found that organic and otherwise sustainably grown fruits and vegetables contained significantly higher levels of both ascorbic acid (vitamin C) and a wide range of polyphenols. The recent discovery of these secondary metabolites in plants has bought our understanding of the biological and chemical complexity of foods to a deeper level of refinement; history suggests we haven't gotten anywhere near the bottom of this question, either. The first level was reached early in the nineteenth century with the identification of the macronutrients-protein, carbohydrate, and fat. Having isolated these compounds, chemists thought they'd unlocked the key to human nutrition. Yet some people (such as sailors) living on diets rich in macronutrients nevertheless got sick. The mystery was solved when scientists discovered the major vitamins-a second key to human nutrition. Now it's the polyphenols in plants that we're learning play a critical role in keeping us healthy. (And which might explain why diets heavy in processed food fortified with vitamins still aren't as nutritious as fresh foods.) You wonder what else is going on in these plants, what other undiscovered qualities in them we've evolved to depend on. In many ways the mysteries of nutrition at the eating end of the food chain closely mirror the mysteries of fertility at the growing end: The two realms are like wildernesses that we keep convincing ourselves our chemistry has mapped, at least until the next level of complexity comes into view. Curiously, Justus von Liebig, the nineteenth-century German chemist with the spectacularly ironic surname, bears responsibility for science's overly reductive understanding of both ends of the food chain. It was Liebig, you'll recall, who thought he had found the chemical key to soil fertility with the discovery of NPK, and it was the same Liebig who thought he had found the key to human nutrition when identified the macronutrients in food. Liebig wasn't wrong on either count, yet in both instances he made the fatal mistake of thinking that what we knew about nourishing plants and people was all we need to know to keep them healthy. It's a mistake we'll probably keep repeating until we develop a deeper respect for the complexity of food soil and, perhaps, the links between the two. But back to the polyphenols, which may hint at the nature of that link. Why in the world should organically grown blackberries or corn contain significantly more of these compounds? The authors of Davis study haven't settled the question, but they offer two suggestive theories. The reason plants produce these compounds in the first place is to defend themselves against pests and diseases; the more pressure from pathogens, the more polyphenols a plant will produce. These compounds, then, are the products of natural selection and, more specifically, the coevolutionary relationship between plants and the species that prey on them. Who would have guessed that humans evolved to profit from a diet of these plant pesticides? Or that we would invent an agriculture that then deprived us of them? The Davis authors hypothesize that plants being defended by man-made pesticides don't need to work as hard to make their own polyphenol pesticides. Coddled by us and our chemicals, the plants see no reason to invest their sources in mounting a strong defense. (Sort of like European nations during the cold war.) A second explanation (one that subsequent research seems to suppport) may be that the radically simplified soils in which chemically fertilized plants grow don't supply all the raw ingredients needed to synthesize these compounds, leaving the plants more vulnerable to attack, as we know conventionally grown plants tend to be. NPK might be sufficient for plant growth yet still might not give a plant everything it needs to manufacture ascorbic acid or lycopene or resveratrol in quantity. As it happens, many of the polyphenols (and especially a subset called the flavonols) contribute to the characteristic taste of a fruit or vegetable. Qualities we can't yet identify, in soil may contribute qualities we've only just begun to identify in our foods and our bodies. Reading the Davis study I couldn't help thinking about the early proponents of organic agriculture, people like Sir Albert Howard and J. I. Rodale, who would have been cheered, if unsurprised, by the findings. Both men were ridiculed for their unscientific conviction that a reductive approach to soil fertility-the NPK mentality-would diminish the nutritional quality of the food grown in it and, in turn, the health of the people who lived on that food. All carrots are not created equal, they believed; how we grow it, the soil we grow it in, what we feed that soil all contribute qualities to a carrot, qualities that may yet escape the explanatory net of our chemistry. Sooner or later the soil scientists and nutritionists will catch up to Sir Howard, heed his admonition that we begin łtreating the whole problem of health in soil, plant, animal and man as one great subject." So it happens that these organic blackberries perched on this mound of vanilla ice cream, having been grown in a complexly fertile soil and forced to fight their own fights against pests and disease, are in some quantifiable way more nutritious than conventional blackberries. This would probably not come as earthshaking news to Albert Howard or J. I. Rodale or any number of organic farmers, but at least now it is a claim for which we can supply a scientific citation: J. Agric. Food. Chem. vol. 51, no. 5, 2003. (Several other such studies have appeared since; see the Sources section at the back of this book.) Obviously there is much more to be learned about the relationship of soil to plant, animals, and health, and it would be a mistake to lean too heavily on any one study. It would also be a mistake to assume that the word łorganic" on a label automatically signifies healthfulness, especially when that label appears on heavily processed and long-distance foods that have probably had much of their nutritional value, not to mention flavor, beaten out of them long before they arrive at our tables. The better for what? question about my organic meal can of course be answered in a much less selfish way: Is it better for the environment? Better for the farmers who grew it? Better for the public health? For the taxpayer? The answer to all three questions is an (almost) unqualified yes. To grow the plants and animals that made up my meal, no pesti- cides found their way into any farmworker's bloodstream, no nitrogen runoff or growth hormones seeped into the watershed, no soils were poisoned, no antibiotics were squandered, no subsidy checks were written. If the high price of my all-organic meal is weighed against the comparatively low price it exacted from the larger world, as it should be, it begins to look, at least in karmic terms, like a real bargain. -- - Billy "Fascism should more properly be called corporatism because it is the merger of state and corporate power." - Benito Mussolini. http://www.youtube.com/watch?v=Arn3lF5XSUg http://radwisdom.com/essays/this-is-your-brain/ |
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