Copper And Organic Crops

Most people who buy organic products wouldn’t like the idea that they are getting quite a bit of copper as part of the bargain. Why copper? Because fungicides based on copper (copper hydroxide, copper sulfate pentahydrate, etc.) are some of the limited options an organic farmer has to control plant diseases caused by fungi and bacteria.

Steve Savage reports,

Many consumers believe that by buying organic they are eliminating exposure to pesticide residues. This erroneous concept is often encouraged by some of those who make organic products or those who advocate for organic. There is a long list (1700 products) of the materials allowed on organic published by the Organic Materials Review Institute (OMRI). The pesticides on this list (including copper fungicides) are definitely real pesticides (they kill pests) and so they have to be registered for use by the EPA like any other pesticide. Copper fungicides are applied to crops frequently and at several ounces per acre each time. Many synthetic alternatives are applied at a few ounces per acre and less frequently. The best synthetic products not only generate far less hazard, their exposure is also far smaller and they actually work better for the control of most diseases.”  (1)

Copper sulfate controls downy mildew fungus, which can devastate grapevines. Downy mildew flourishes in wet weather showing up initially as a downy patch on the bottom of the leaf. If rain persists, the fungus establishes itself, eventually destroying the crop. It can even carry over into the next season.

In 2018, without anything near the debate surrounding glyphosate, the European Union decided to reauthorize the fungicide copper sulfate, a popular pesticide among organic farmers that has a more toxic rap sheet than glyphosate.  So copper sulfate and other copper compounds are the most popular class of pesticides used in Europe. They are a natural compound and widely used by organic farmers as an algaecide, bactericide, fungicide, and root killer. (2)

Copper sulfate works by binding tightly to proteins in fungi, algae, and other organisms. It then causes the cells to leak, killing the target (and some non-target) organisms. It can also persist through rain and stick to plants, which also causes some of the environmental problems both farmers and regulators have seen.

Copper compounds including various copper sulfates but also copper hydroxides have been in use by almost all farmers, including many conventional ones because the safer, targeted synthetic versions used by some conventional farmers are not as effective as the more toxic organic copper products.

Most countries in Europe use about 1.5 to 2 times the amount of pesticides per acre than the US, mostly because of the use of copper compounds, primarily on vineyards, as they control mildew. They are also used in other aspects of organic farming, especially with potatoes, grapes, tomatoes and apples. (3)

Does organic mean safe? Not in the case of copper compounds. Just because organic compounds are organic, does not mean they are safer. In fact, organic copper products are one of the most toxic chemicals used anywhere in farming. Studies show that soil copper in conventional and organic vineyards had lower soil microbial activity in organic vineyards, which had higher copper concentrations than conventional fields.

Highest concentrations were measured from vine leaves. Copper cycling is very slow, so it can accumulate in large amounts in the soil over time. Too much copper can cause chlorosis of vine leaves.

Copper compounds don’t biodegrade and can essentially ‘kill’ the soil, rendering it useless, if not properly managed. It is also bio-accumulative, meaning it can build up to toxic levels in the soil. In fact, many organic wine growers, in the US and in Europe (including France) have opted out of their organic designation in order to use alternatives to copper sulfate fungicide. Their fears? Accumulation of the chemical in soil.

As a fungicide, copper sulfate is pretty much the only possible recourse for organic winemakers looking to eradicate downy mold and mildew, which  usually means death to wine vines.

You kind of don’t have a choice.” says Caroline Connor, an expert wine teacher. “If you’re dealing with mildew and rot, copper is one of the only things that organic producers can do.” “It’s hard to follow the organic regulations in places that are wet,” adds Connor.

In the US, copper compounds are permitted for both conventional and organic use. For California, copper is by far the most commonly applied active ingredient against fungus. Nationwide, about 400,000 pounds of copper hydroxide is used on grapes, representing about 65 percent of all wine grapes grown in the US. In addition, about 100,000 pounds of copper sulfate pentahydrate is used (about 15 percent of grape crops).  (3)

Vintners say that without effective alternatives to copper, crop loss in damp years will make organic vineyards economically unsustainable, forcing them to turn to synthetic chemicals or bankruptcy.

But risk assessments by public authorities show that copper compounds pose risks for farm workers, birds, mammals, ground water, soil organisms, and earthworms. These risks make copper unpalatable for many vintners. (4)

Alternatives

Scientists have come up with promising innovations, some with ties to organic and biodynamic (holistic, ecological and ethical approach to farming) methods. Meanwhile, the French National Institute for Agronomic Research, has been busy creating disease resistant grape varieties.

The main lesson seems to be that organic farming cannot only look to past methods if it is to move into the future. (4)

References

  1. Steve Savage, “An unlikely pair: heavy metal and organic produce,”  redgreenandblue.org, September 27, 2010
  2. Andrew Poerterfield, “Far more toxic than glyphosate: copper sulfate used by organic and conventional farmers, cruises to European reauthorization,” geneticliteracyproject.org, March 20, 2018
  3. Andrew Porterfield, “Organic pesticide copper sulfate—unlike glyphosate—is a carcinogen, kills beneficial insects, decimates soil, pollutes water. It also works. Here are political and science reasons why regulators give it a free pass”, geneticliteracyproject.org, July 13, 2021
  4. Suzanne Mustacich,”Is copper safe for wine?”, winespectator.com, November 29, 2018

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Comments (12)

  • Avatar

    sir_isO

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    Uhm, so I take it you’ve never heard of potassium bicarbonate, sulphur, phosphor, hydrogen peroxide, salycilic, asorbic, citric, caprylic, etc acid, never heard of terpenes, essential oils, phenols, methanol, etc?

    All of those “diseases” are related to plant status. I have never seen any “contagion” of anything ever, without enabling means. Ever. In any sort of agriculture, or disease in people. None, ever. All of that is explained by the plant/individual status, environment, practices.

    Like people who lack antioxidants, vitamins and minerals in winter and think “Oh, it’s not that we’re deficient and toxified, as we are, it’s that a magical mythical phantom virus infected us. And we clamour for immunity, immunity that is physically impossible, that we never attain, but not only that…but we believe immunity can be achieved with more toxins and never addressing those OBVIOUS factors and essentials”

    Humans are retarded.

    Reply

    • Avatar

      Andy

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      Yes thank you I have heard of all those items.

      Reply

      • Avatar

        sir_isO

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        It’s a Bayer ad.

        Reply

  • Avatar

    sir_isO

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    Your agricultural diseases result from your agricultural practices and ignorance.

    The same shit applies to the farmed cattle known as the zombiedronerobosheepclones. Things get sick because your methodologies, your principles, your practices are HORRIBLY FLAWED.

    Reply

  • Avatar

    Andy

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    Well that told us didn’t it.

    Reply

  • Avatar

    sir_isO

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    Btw, I absolutely destroyed that worthless souled shill, Andrew Porterfield, on his site a few years ago, neither him nor his team had any response.

    Reply

  • Avatar

    sir_isO

    |

    There is a saying, any good horticulturist knows.

    “You try somethings once or twice, if it fails after a third time, you’re doing it wrong”.

    That’s a problem the entirety of the agricultural system has. It tries to force things, nature tells it “Sorry bro, have some palmer amaranth”.

    Reply

  • Avatar

    Howdy

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    Personally, I would paint it onto the leaves.

    Reply

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