Empirical evidence: organic/biodynamic vit = more textured wines

A six-year comparison of organic, biodynamic, and “low-input” and “high-input” viticulture (three years of conversion, three of maintenance) recently came to fruition in South Australia, courtesy of researchers at the University of Adelaide. The full report is freely available here (and three cheers for research freely shared). It’s 73 pages long, but the conclusions are fairly simple. The most worthwhile among them: in blind trials, experienced wine professionals rated the organic and biodynamic wines more interesting than the conventional versions.

  • Soil health (nitrogen, phosphorus, organic carbon, microbe mass) was most strongly improved by compost, not by any particular management system. All four systems were tested with and without compost.
  • Compost had the single most dramatic positive effect on soil health, no matter the underlying management system.
  • Management system had no consistent effect on vine growth, berry weight, or berry composition.
  • Low-input, organic, and biodynamic alternatives yielded at 91%, 79%, and 70%, respectively, of the high-input condition.
  • Organic and biodynamic wines were more “textural, rich, vibrant, and spicy” than their conventional counterparts. (pH, TA, and color held constant; high-input wines were a bit higher in alcohol.)

Improved soil health with organic/biodynamic management has been demonstrated numerous times over, and so have the benefits of compost. This study was unusual in making compost a separate variable, showing that both organics/biodynamics and compost, separately, were beneficial. The upside here is the attitude, across the study, that conventional growers can benefit from organic techniques even without undertaking a full-on organic conversion.

The downside is that the “organic” and “biodynamic” management used in the comparison are weak compared with what many committed non-conventional growers undertake. How can you practice biodynamics without compost? “Biodynamic” here seems to have meant nothing more than adding the core preparations 500 and 501, a far, far cry from anything Demeter would certify as honest biodynamics. Even the organic system is pretty bare bones: weed control with mowing and cultivation instead of herbicides; no insecticides or pesticides other than copper. (The low-input condition pulled back on the insecticides and some of the pesticides.)

Talking about those lower yields, the researchers make an important point. Very little research has been done on organic or biodynamic cultivation methods. We could develop better techniques within those systems and preserve environment and fruit quality while improving yields. Many organic/biodynamic growers have surely worked out such techniques on a local scale, which leaves a role for scientists to listen to what they’re doing, identify why it works and how/whether it can be generalized more broadly. Some environmentally conscious wine people are happy to pour their big pharma money (or whatever it might be) into projects they believe in with no thought for financial return, but most are trying to support their families as well as their values. Sharing successful organic/biodynamic techniques — say, for weed management, which was the biggest issue in this study — developing them scientifically, and stamping them with a scientific seal of approval so that they’re not dismissed as just those quacky organic people, will help conventional growers improve their weed management tactics, too. Likely, too, with economic benefits you can appreciate even if you honestly don’t care about trashing the environment for short-term gains.

The researchers should have made another point about those yields. Are the high-input yields a reasonable benchmark? Should we buy short-term gains with long-term environmental and social damage? If your business isn’t “sustainable” without using chemical warfare to eke every last grape out of the earth, then perhaps you need to reconsider your business practices in other areas. It comes back to the old resurrecting dinosaurs argument. Just because we have the technology to do something doesn’t mean we should. The wine might even be more interesting.


14 thoughts on “Empirical evidence: organic/biodynamic vit = more textured wines

  1. Using synthetic copper pesticide, which is allowed in BioDynamic farming, means that copper, a toxic heavy metal, which sterilizes soil, is being used over and over in these BD vineyards to prevent mildew. This is terrible for the environment. Certified Sustainable viticulture has the same composting and cover cropping of organic and BD without the negative environmental damage.

    • I understand your concerns about copper, John, but I’m not sure that what you’re saying makes sense. There are many different “certified sustainable” systems and, while I’m not familiar with all of them, my understanding is that they certainly allow copper use in the vineyard. Individual vineyards choosing to use less copper is great, but I don’t see how copper is part of the conversation about conventional s “sustainable” (as it’s variably defined) vs organic vs biodynamic practices.

      • New Class IV low risk pesticides replace many copper applications, which will reduce annual environmental impact. I was surprised to see no Stylet Oil mentioned as being used in the organic / biodynamic vineyards. Do you think it is an oversight?

      • The methods these folk outlined were pretty bare-bones, as I mentioned, so I don’t think that not using any of the various organic alternatives to standard practice was an oversight, just a choice. Whether that choice was about comparing very simple regimens to see whether those very simple changes could produce a demonstrable effect or whether it was just a matter of keeping the experimental design and management protocols as simple as possible I couldn’t say, but, again, the results seem to reflect well on organics in basic principle.

      • I do not believe we have enough information to say that this reflects well on organics. Annual environmental impact is cumulative of all pesticide applications. Here we are being told a synthetic copper based pesticide (a heavy metal) is being used multiple times and this specific pesticide has one of the highest negative environmental impacts plus the dose used may be quite large. From what I see here, I could see much damage being done to the environment versus a non organic approach.

      • Ah. Perhaps I didn’t make this clear in the original post — I’ll emend it — but copper was applied in ALL of the treatments, including the high- and low-input conventional approaches. While specific application frequencies in each case weren’t detailed (a weakness of the report), I think that we need to say that any damage related to using copper happened in the conventional approaches in addition to the damage from pesticide and insecticide use.

  2. The concern about copper expressed above is certainly well-founded, but given the array of biological and cultural alternatives available today copper is unnecessary in many vineyard environments. We haven’t used it in our (certified organic/Demeter Biodynamic) Oregon vineyard in at least 15 years…A combination of good canopy management and some of today’s biological fungicides does the trick every season.

    • Again, as for all controlled studies, this represents one point in time of a limited set of conditions. It’s unquestionably true that growers across the management style spectrum are using different and better practices than the ones used here. Mainstream scientific research hasn’t spent much time studying organic/biodynamic/alternative practices, unfortunately, but that’s slowly beginning to change and I’m hoping that we’ll see more nuance in the variables used in these studies in the future.

    • Doug, can you list the brand name of all pesticides you used in 2014 plus the total usage amounts and give me your total vineyard acreage? I am doing comparisons of farming methods. Are Oregon farmers required to file Pesticide Usage Reports with the county or state? If so, what is this report called and can it be accessed online or by request?

  3. I notice a few other things:
    1. Objective tests show higher anthocyanin and phenolic levels in non-organic and non- biodynamic test sites compared to the other management systems. This is a surprising win for non-organic and non-BD: wine quality involves higher anthocyanin and phenolic levels.
    2. Wine tastings are notoriously unreliable. I would not trust this information as much as the hard data in 1.
    3. Note this test involved very fertile fields. One constant error in comparing organic/BD to conventional farming is the use of fields that are fertile so we do not have a real world test. Organic/BD struggle to get YAN levels adequate for fermentation and often result in lower quality wines. This essential real world situation was compromised in these tests.
    4. Yields were lower in organic/BD. But how do you calculate yields when manure is involved. Other agricultural fields are required to grow the feed for the green house gas producing animals who are doing quantifiable environmental damage.

    • John: 1. And the high-input wine also ended up at a higher alcohol. The authors don’t go into detail here, but we could infer that the high-input condition resulted in a “bigger” wine, certainly preferable to some from S. Australia, but perhaps not to everyone. 2. If you’d like to ignore tasting data, that’s fine, but this is what their tasting data showed. 3. Again, this is one test using one vineyard and, as I understand it, their selection wasn’t peculiar for South Australia. 4. I’m confused by your question. “Yield” here was the typical measure of tonnes per hectare (though more detail on experimental methods in the report would have been nice).

      • Tasting data is very subjective. Hodgkins statistically showed how inaccurate the awarding of medals at State Fairs can be: completely random.

        Yields interest me as a sustainable farmer in order to prevent the clearing of additional land as demand grows. When we use manure, we are also creating a parallel farm where the animals providing the manure must have their feed grown. The costs of moving manure makes its use expensive, it’s heavy and bulky and is often shipped long distances. In addition, we are trying to reduce livestock numbers because of their production of green house gases and their use of land that could be used to grow human crops. Sustainable farming is all about yield vs environmental impact.

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