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Article suggesting organics is still being pioneered... (heavy metal concern)

Discussion in 'Organic Lawn Care' started by JDUtah, Sep 15, 2008.

  1. JDUtah

    JDUtah LawnSite Silver Member
    from UT
    Messages: 2,636

    Hey guys, it's an agg article, but I think might apply. My family pointed me to it. I think it is something to take into consideration, but not discourage us...

    Part of the article...

    "Scientists have known since the 1920s that organic fertilizers used by farmers to supplement conventional systems—composted animal manure, rock phosphates, fish emulsions, guano, wood ashes, etc.—further contaminate topsoil with varying concentrations of heavy metals. Organic advocates, who rely exclusively on these fertilizers, remain well aware of the problem today, although they rarely publicize the point.

    No one is saying that organic soil has higher heavy-metal counts than conventional soil as a rule—scientists have not conducted enough research to make such a determination. Still, some evidence indicates that organic soil can, in some cases, be more contaminated. George Kuepper, an agriculture specialist with the National Center for Appropriate Technology, observed in a 2003 report that composting manure actually concentrates the fertilizer's metal content, which could lead to greater levels of the contaminants in organic soil.

    Recent studies have lent Kuepper's concern tentative support. For example, in 2007, researchers conducted an analysis of wheat grown on various farms in Belgium; based on the results, they estimate that consumers of organically grown wheat take in more than twice as much lead, slightly more cadmium, and nearly equivalent levels of mercury as consumers of wheat grown on conventional farms.

    Beyond the comparative impact of organic vs. conventional systems on the soil's heavy-metal concentration, there's the question of how easily these trace elements enter crops. Although the research here is also relatively thin, what has been done suggests that the problem of plant uptake is equally serious in both organic and conventional systems. For example, 14 percent to 28 percent of New Zealand's cattle (destined to be organic beef) were found to have kidney cadmium levels exceeding limits set by the New Zealand Department of Health because of a diet of plants grown in contaminated soil. Similarly, a 2007 study of Greek produce found that organic agriculture does not necessarily reduce the cadmium and lead levels in crops. As it turned out, "certified" organic cereals, leafy greens, pulses, and alcoholic beverages had slightly less heavy-metal contamination than conventional products, but "uncertified" organic products had "far larger concentrations" than conventional ones.

    These findings might be preliminary and inconsistent, but pressure is mounting on the organic community to take action. Under rules set by the USDA's National Organic Program, responsibility has been left to the individual farmer to manage plants and animals in a way that does not contaminate crops with heavy metals. The question of how to monitor that responsibility, however, is complicated by the fact that there are as yet no federal limits on heavy-metal concentrations applicable to all fertilizers.

    Organic farmers thus work with broad suggestions rather than concrete federal regulations. They're routinely forewarned by organic watchdog groups such as the Organic Trade Association about dangerous levels of copper and arsenic in poultry manure. They're reminded of proper "nutrient management planning" and encouraged to experiment with the relationship between soil pH levels and rates of heavy-metal contamination. They're advised to test soil regularly for heavy metals and to adjust fertilizer combinations and relative nitrogen, phosphorous, and potassium levels in the soil when metal concentrations rise. A handful of states—California, Oregon, Washington, and Texas among them—have established loose legal guidelines. But the fact remains: The decentralized sprawl of information about fertilizers and heavy metals fosters a far-flung approach to the problem.


    Fortunately, complete despair may still be avoided. Consider this: Plant biologists are working to genetically modify a fern plant that, when ashed and dusted on soil, is capable of sucking up zinc. The dust can then be gathered so the recovered zinc may be recycled and put to better use. Of course, in order for bioremedial technologies such as this to move forward, the dichotomy between organic and conventional agriculture will have to be collapsed, a sober view of organic agriculture will have to be adopted, and we'll have to read the banana leaves with greater skepticism. "

  2. ICT Bill

    ICT Bill LawnSite Platinum Member
    Messages: 4,115

    What you point out is true, the article is a little skewed but basicaly true.

    All manufacturers of fertilizer whether "organic" or not must have a heavy metals analysis done on their product and it has to be available to anyone buying the product. If the product is too high in any certain heavy metal it can be blocked rom sale from the state regulator. When using your own manure this is often bypassed but is forced when certifying the farm for organic production

    To be a certified organic grower you can not use any urea or what is considered synthetic fertilizer so many of the tools that farmers are used to using are taken away in organic farming.

    Some other issues that recycling manure has especially when treating pasture is that the field over time become heavy with SOM, 9% can be a normal reading, as the fields become more and more fungal over time the PH begins to rise to 8, 8.5 even up to 9, this makes it more difficult to grow orchard grass and such. We are actually working with 2 farms for just this thing. We turn their sludge ponds into really big compost tea brewers, like 1,000,000 gallons big, and use different mixes depending on the site to balance the sludge water used before it goes out into the field.
  3. Tim Wilson

    Tim Wilson LawnSite Senior Member
    Messages: 795


    If you read the report written by George Kuepper it is evident that most heavy metal contaminents in manure and manure based compost originate from industrial chemical inoculated feed; part and parcel of the chemical agriculture industry. Apart from an isolated case in Australia where graze apparently grew in contaminated soil (the rancher's fault for not testing), the article is mostly blather which does not make much of a valid point. It does illustrate the need for composters to be astute in questioning what their source of manures are and what the animals were fed. And to ensure a carbon to nitrogen ratio of 1:30+. It also demonstrates the need for a fall back to the small family farm system, where livestock feed is grown or acquired locally and compost is made with on farm materials. Nature farming like Cuba, parts of; the Phillipines, Thailand, India.

    In my opinion for the author to translate the points made in these reports and to apply them across the board is irresponsible.
  4. JDUtah

    JDUtah LawnSite Silver Member
    from UT
    Messages: 2,636

    Thanks for the input guys.

    I imagine that eventually there will be heavy metal regulations, even in organic maintenance. Do you think so? I also think it would be on the compost/ferts we use, hopefully not having to test each property.

    Hmmm, I know it is relative, but do you know how much those tests normally run?

    Just trying to see what I can/should do to help sell credible practices.
  5. Tim Wilson

    Tim Wilson LawnSite Senior Member
    Messages: 795

  6. ICT Bill

    ICT Bill LawnSite Platinum Member
    Messages: 4,115

    The ones we do are pretty extensive and cost hundreds of dollars, I believe just less than $1000.00. If you would like to see what one looks like email me and I'll send our latest on our 1-2-3 Compost Tea from March

    This article really got some traction, I am seeing it in other places too, its complete nonsense, but someone got that thing distributed very well
  7. phasthound

    phasthound LawnSite Fanatic
    Messages: 5,056

    It's been a long time since we left Eden. Everything is contaminated to some degree.
  8. Tim Wilson

    Tim Wilson LawnSite Senior Member
    Messages: 795

  9. treegal1

    treegal1 LawnSite Gold Member
    Messages: 3,911

  10. Kiril

    Kiril LawnSite Fanatic
    Messages: 18,334

    Syntax Police Warning. :)

    Ratio is backwards -> 30:1 -> carbon:nitrogen

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