Inexact Change

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Cows Against Climate Change: The Dodgy Science Behind the TED Talk

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“We were once just as certain that the world was flat. We were wrong then, and we are wrong again.” That’s what Allan Savory had to say at TED about science’s view of desertification, a form of land degredation in which land loses its vegetation and bodies of water1. For years, scientists have believed that overgrazing by livestock is a major cause of desertification, and Allan Savory shared this opinion as a young biologist. Now Savory argues that we can prevent desertification by grazing more animals, with their movement carefully planned to mimic nature.

TED curator Chris Anderson dubbed Savory’s talk the highlight of the year’s conference and the official TED Twitter feeds described the talk as “profound and important.” Predictably, the talk was cheered by pastured meat enthusiasts, with Michael Pollan appearing ready to recant his advice to eat “mostly plants”:

Savory’s talk was also well-received in typically level-headed corners of the Twittersphere, with Discover Magazine calling it “one of the most thought-provoking” talks of the year, and Michael Shermer declaring it “moral progress in climate change.”

As C.J. Hadley’s profile in the February 2000 issue of the journal Rangelands makes clear, Savory has led an interesting life. He was born and raised in Zimbabwe (then Rhodesia), and worked in biology, military, politics, and other fields. Once a staunch opponent of grazing, he came to believe that we need more cows rather than fewer. As he told Hadley, “Severe grazing is absolutely essential to maintain biodiversity.” Overgrazing, he argues, is not the cause of desertification, arguing that grasslands have historically evolved with grazing animals. He now believes that the problem is poorly-planned grazing, and he now advocates for “holistic management and planned grazing” in order to address “all of nature’s complexity and our social, environmental, economic complexity.” According to Savory, well-planned grazing promotes plant growth, and the action of animal hooves on the soil improves the soil’s absorption of water. These ideas support the view that well-planned animal grazing can prevent and reverse desertification, thereby helping to combat climate change.

Savory fled Zimbabwe for Texas in the 1970s. In 1984 he and his wife, Jody Butterfield co-founded the non-profit Center for Holistic Management (later renamed the Allan Savory Center for Holistic Management and then the Savory Center and then Holistic Management International) to promote his approach to cattle grazing and land management. In 1992, the couple founded the Africa Centre for Holistic Management, which aimed to promote the same methods in Africa. More recently, Savory and Butterfield have left Holistic Management International to start the for-profit Savory Institute, another organization devoted to promoting Savory’s Holistic Management methods. 2

Savory’s methods have found little support from mainstream science. The same issue of Rangelands that featured Hadley’s profile of Savory also included an article by Jerry L. Holechek and others, which attempted to review the evidence for a number of Savory’s claims. Their review of studies from 13 North American sites and additional data from Africa found little evidence for any of the environmental benefits which Savory claimed for his methods. Moreover, the research consistently indicated that “hoof action from having a large number of animals on a small area for short time periods reduced rather than increased infiltration,” seemingly contradicting a key assumption of Savory’s methods.

In a letter to the editor of Rangelands that June, Savory dismissed Holechek’s findings, pointing out that the cited studies considered “short duration grazing” schemes rather than the Holistic Management methods for which Savory advocated. He explained, “The work Holechek et al. describe is unlike any range management practice I have ever advocated…In fact I have consistently stated that all grazing systems and rotations, including short duration grazing, will fail.” 3 As Savory explained in 1983, a key difference between short duration grazing and Savory’s Holistic Resource Management is that the latter method is “time-controlled,” adjusting grazing periods in accordance with the rate of plant growth.

Savory went on to describe what he identified as the only research trial ever conducted on his methods, which took place in Zimbabwe in the 1960s. The experiment, known as the Charter Grazing Trials and undertaken with Savory’s involvement, tested the claim that “we could double the stocking rate on any land under conventional management, improve the land and make more profit” with Savory’s methods. Savory reports, “The only trial ever conducted proved what I have always advocated and continue to advocate when livestock are run on any land.”

In general, it is unlikely that a single study on a few plots of land will definitively prove a statement about “any land.” Moreover, while I haven’t seen the original papers (which were published in the Zimbabwe Agricultural Journal), Holechek summarized the published work in a later issue of Rangelands, finding relatively weak support for Savory’s methods.

A further complication with the Charter Grazing Trials is that, as Savory’s letter notes, it tested “the planned grazing process then called short duration grazing, but today called Holistic Planned Grazing.” Indeed, Savory wrote in his 1983 Rangelands piece, “For those without a deep knowledge of Short Duration Grazing, I am extremely familiar with this grazing system as I developed it.”

The best I can do to make sense of all this is to put everything in the context of Savory’s explanation of his method. In his 1983 article in Rangelands, Savory explained that the best analogy for what was then called the “Savory Grazing Method” was a computer:

If you know what you want to do with the computer and you feed in the right information it will aid you in achieving the result rapidly and surely. If some factors change and you observe the changes and feed in the new information the computer will again aid you efficiently in getting to your goal.

Thus, it is not necessarily contradictory for Savory to claim to have developed short duration grazing, that short duration grazing doesn’t work, and that the methods for which he has always advocated have been proven to work. The key is that the method that would become short duration grazing was the output of Savory’s “computer” when he fed in the information that was relevant to that situation. 4

That said, this ought to serve as a warning against the folly of claiming a single study as proof of anything. If the Charter Grazing Trials are proof of something, why is it not short duration grazing which was validated by its results? It is, after all, the method that was employed in the study. For Savory to now say that short duration grazing is a failure, he has to concede that a single study doesn’t prove the effectiveness of a method on “any land.”

Holechek’s 2000 article also claims that Savory had “expressed doubt that holistic resource management could be validated experimentally.” While I was not able to find a precise reference for this claim, Savory did not deny it in his response, and elsewhere he has expressed some reservations about scientific testing. For instance, in Hadley’s (mostly favorable) profile, he made it clear that he saw little use for the scientific method:

You’ll find the scientific method never discovers anything. Observant, creative people make discoveries. But the scientific method protects us from cranks like me.

While the intended irony of this statement has not escaped me, it’s hard to read it without concluding that he sees the scientific method as an obstacle to progress, rather than a tool for achieving it.

That is problematic because the scientific method is what will tell us whether Holistic Management works. Savory would like us to graze more cattle to fight desertification and climate change, even as scientific evidence indicates that his “solution” will actually exacerbate these problems. If we were to employ Savory’s methods on a large scale and they were to succeed in stopping desertification, that would constitute excellent experimental validation of those methods. 5 If we can’t experimentally validate his methods, then we cannot know them to work in real life, either. It is thus perfectly reasonable to ask for evidence on a smaller scale before we try such a thing, particularly as existing evidence indicates that this would make the problems worse. As Chad Kruger writes, “Being ‘unconventional’ is not, in itself, a problem, but when what you are arguing for is unconventional, you’d better ‘bring data.’”

It is also important to note that for all Savory’s insistence that his methods work, it has been associated with a number of failures. For instance, Hadley mentions a test farm in Zimbabwe, which collapsed as soon as Savory fled that country. Whereas those on the farm blamed the collapse on drought, Savory blamed on their lack of proper planning in his absence.

This is typical of Savory’s response to failure. The fault never lies in his methods but in people’s implementations of them. For instance, in a 1990 paper in the journal Ecological Economics6, Savory explains away “15 years of frustrating and eratic [sic] results” with the admission that “we had confused the integrated approach with the holistic approach, thinking that the terms were synonymous,” emphasizing that “the breakdowns we were experiencing were not attributable to the basic concept being wrong but were always due to management–of the people and the finances.” 7 Even after Savory realized that “the integrated approach and the holistic approach were opposites,”8 he had to struggle with “understanding not only what ‘holistic’ meant, but even more difficult, how to apply such an approach in day-to-day management.” Even when his own implementation of his own ideas leads to failure, he believes that the problem isn’t that the methods were flawed but that he didn’t fully understand them.9 It is this kind of convoluted reasoning that allows him to claim that his methods work.

In a review of Savory’s 1988 book Holistic Resource Management, M.T. Hoffman wrote “The apparent inconsistencies and lack of definitions (eg. for concepts such as complexity, stability, resilience, diversity and production which have a number of different meanings in the ecological literature), render it frustratingly difficult to compare his [Holistic Resource Management] approach with the broader literature.” Imprecise language doesn’t just make it hard to compare Savory’s methods with the existing literature. It also makes it nearly impossible to evaluate his approach scientifically because it allows Savory to blame any failures on a misunderstanding of the method. So long as nobody can understand Savory’s ideas, those ideas can’t be tested or disproven. In this framework, problems are solved not by trying different methods but by developing a “better” understanding of the existing one. It is therefore little wonder that after members of the Department of Range and Forage Resources at the University of Natal - Pietermaritzburg–Savory’s alma mater–met with Savory, they reported that it would be “extremely difficult” to test Savory’s ideas because “it would be difficult to evaluate even a short-term research endeavour (of 5 to 10 years), as the approach taken by Holistic Management proponents would surely have changed by then, as it has in the past.”

Changing one’s mind in response to new evidence isn’t bad at all. Indeed, it’s the scientific thing to do. However, that is not the kind of change that one finds in Savory’s writings. Savory insists that he’s been correct all along and that his evolution flows naturally from an improved understanding of his own bulletproof ideas. Whereas the scientific method lends itself well to self-correction, Savory’s vague language and inconsistency will lead to trying many different things without reason to expect improvement.

Savory argued at TED that Holistic Management “offers more hope for our planet, for your children, and their children, and all of humanity.” What Savory does not tell us is that there is the distinct possibility that if we try to implement those ideas, we will fail. In this case, he will tell us that we misunderstood his ideas. How comforting it will be to know that his ideas were correct, as they always have been!

In December, TED responded to concerns that independent TEDx authorized events were “dragging the TED name through the mud” by sending a letter to “the TEDx community” warning that bad science could lead to revocation of the TEDx license. The letter also included some advice for identifying bad science. I can’t help but think that Savory’s work should have raised concerns for anybody familiar with that list. At the least, Savory’s work “has failed to convince many mainstream scientists of its truth,” much of it “is not based on experiments that can be reproduced by others,” it comes from an “overconfident fringe expert,” and it uses imprecise vocabulary to form untested theories.

Of course, TED has no contractual incentive to apply the standards it sets for TEDx organizers to its own talks. However, the letter emphasizes that “your audience’s trust is your top priority,” and I think it’s fair to ask what TED did to respect that trust in this case. Did they research the science behind Allan Savory’s ideas? Are they satisfied that his talk amounts to “good science”? If Savory’s talk had run at a TEDx event, would that event’s license have been revoked? Now that TED has reined in TEDx, perhaps its next move should be to look in the mirror.

Further reading

  1. An earlier version stated that desertification was “a form of land degradation in which land turns to desert.” Chris Clarke’s excellent takedown of Savory’s talk taught me that this wasn’t right. ↩

  2. Although the reason for Allan Savory’s departure from Holistic Management International is not clear to me, Butterfield has edited Savory’s Wikipedia page to remove references to Holistic Management International, which seems to hint at less friendly relations between the organizations.↩

  3. Curiously, Savory’s 1978 article “A Holistic Approach to Ranch Management Using Short Duration Grazing,” published in the Proceedings of the First International Rangeland Congress devoted several paragraphs to explaining short duration grazing, not once mentioning that it would fail. Instead, the article stated, “An immediate doubling of production is not uncommon on ranches which were considered fully stocked before changing to short duration grazing.”↩

  4. Savory has used a number of terms for his methods over the years, including short duration grazing, Savory grazing method, holistic resource management, holistic management and holistic planned grazing.↩

  5. This would not necessarily confirm that Savory had identified the correct mechanisms by which Holistic Management worked. It would merely show that they worked.↩

  6. An earlier version of this post included a link to the wrong article here. I corrected the link at 7:30PM on April 4, 2013.↩

  7. I added the end of this sentence post-publication (March 12, 2013 around 2:00AM PDT), starting from “emphasizing” because I thought it improved clarity.↩

  8. Savory goes on to write, “Since then an Englishman (Goldsmith, 1988) came to the conclusion not that [holistic and integrated] are opposites but that the integrated approach is still disciplinary while the holistic approach is non-disciplinary. I prefer his description which I think is more accurate than my own.”↩

  9. In the language of his analogy, Savory points out that early computers were capable of performing computations correctly, but it was hard to achieve accurate results because the machines were not user-friendly.↩

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