When Allan Savory finished his TED talk early last month, foodies worldwide collectively salivated. In roughly 22 minutes, Savory, a biologist and former member of the Rhodesian Parliament, challenged the conventional wisdom blaming livestock for the degradation of global grasslands into hardpan deserts. It has long been a basic tenet of environmentalism that 10,000 years of overgrazing has caused this desertification. Environmentalists insist that to restore degraded landscapes, we must reduce the presence of cattle, eat less meat, and allow ecosystems to repair themselves. Savory, who admits that he’s suggesting “the unthinkable,” wants humans to do the exact opposite: Add cattle to the deserts, manage them with obsessive precision, and eat more meat. Most of the world’s land, he says (at about 18:40), “can only feed people with animals.”

Savory’s hypothesis hinges on what he calls “holistic management and planned grazing.” These methods are designed to re-enact the movements of the prehistoric herds that once nurtured global grasslands with their manure deposits and “hoof action” (gentle trampling that increases the soil’s ability to hold water). By mimicking the natural symbiosis between plants and animals, holistic grazing would, Savory argues, encourage the regrowth of carbon-sequestering grasslands. These grasses would absorb enough carbon to counteract the methane production that’s associated with cattle husbandry (thanks to cow burps and farts) and halt global warming. (To put that claim in perspective, note that the Earth’s oceans and plants currently absorb only half of the 7 billion metric tons of carbon that human activities release into the atmosphere each year.) In order for Savory’s plan to work, the stocking density of livestock—the number of animals grazing a given area of land—would need to increase, in some cases, by as much as 400 percent. And for ranchers to make a living, they would sell their beef.

Savory’s speech quickly attracted praise. Chris Anderson, the TED host, said to Savory after his show, “I’m sure everyone here … wants to hug you.” Michael Pollan, a passionate advocate of pastured beef, called Savory’s talk the “highlight of TED” in a tweet that provocatively asked, “Eat MORE meat?” The Organic Consumers Association published an article that used Savory’s presentation to assert that “what we need is MORE moving, grazing animals, not less,” and to argue that holistic grazing “would be beneficial for the environment, the health of the animals, and subsequently the health of humans consuming those animals.” The takeaway was clear: If you’re interested in saving the planet, sharpen your steak knives.

Well, not so fast. For all the intuitive appeal of “holistic management,” Savory’s hypothesis is beset with caveats. The most systematic research trial supporting Savory’s claims, the Charter Grazing Trials, was undertaken in Rhodesia (Zimbabwe today) between 1969 and 1975. Given the ecological vagaries of deserts worldwide, one could certainly question whether Savory’s research on a 6,200-acre spot of semiarid African land holds any relevance for the rest of the world’s 12 billion acres of desert. Extrapolation seems even more dubious when you consider that a comprehensive review of Savory’s trial and other similar trials, published in 2002, found that Savory’s signature high-stocking density and rapid-fire rotation plan did not lead to a perfectly choreographed symbiosis between grass and beast.

Instead, there were problems during the Charter Grazing Trials, ones not mentioned in Savory’s dramatic talk. Cattle that grazed according to Savory’s method needed expensive supplemental feed, became stressed and fatigued, and lost enough weight to compromise the profitability of their meat. And even though Savory’s Grazing Trials took place during a period of freakishly high rainfall, with rates exceeding the average by 24 percent overall, the authors contend that Savory’s method “failed to produce the marked improvement in grass cover claimed from its application.” The authors of the overview concluded exactly what mainstream ecologists have been concluding for 40 years: “No grazing system has yet shown the capacity to overcome the long-term effects of overstocking and/or drought on vegetation productivity.”

The extension of Savory’s grazing techniques to other regions of Africa and North America has produced even less encouraging results. Summarizing other African research on holistically managed grazing, the same report that evaluated the Charter Grazing Trials found “no clear cut advantage for any particular form of management,” holistic or otherwise. It noted that “more often than not” intensive systems marked by the constant rotation of densely packed herds of cattle led to a decline in animal productivity while doing nothing to notably improve botanical growth.

A 2000 evaluation of Savory’s methods in North America (mostly on prairie rangelands in Wyoming, Oklahoma, Texas, and New Mexico) contradicted Savory’s conclusions as well. Whereas Savory asserts that the concentrated pounding of cow hooves will increase the soil’s ability to absorb water, North American studies, according to the authors, “have been quite consistent in showing that hoof action from having a large number of animals on a small area for short time periods reduced rather than increased filtration.” Likewise, whereas Savory insists that his methods will revive grasses, “the most complete study in North America” on the impact of holistic management on prairie grass found “a definite decline” of plant growth on mixed prairie and rough fescue areas. It’s no wonder that one ecologist—who was otherwise sympathetic toward Savory—flatly stated after the TED talk, “Savory’s method won’t scale.”

Even if Savory’s plan could scale, foodies would still have to curb their carnivorous cravings. The entire premise of any scheme of rotational grazing, as Savory repeatedly notes, is the careful integration of plants and animals to achieve a “natural” balance. As Dr. Sylvia Fallon of the Natural Resources Defense Council has shown, symbiosis between grazing herds and grasses has historically worked best to sequester carbon when the animals lived the entirety of their lives within the ecosystem, their carcasses rotted and returned their accumulated nutrients into the soil, and human intervention was minimal to none. It is unclear, given that Savory has identified this type of arrangement as his ecological model, how marketing cattle for food would be consistent with these requirements. Cows live up to 20 years of age, but in most grass-fed systems, they are removed when they reach slaughter weight at 15 months. Cheating the nutrient cycle at the heart of land regeneration by removing the manure-makers and grass hedgers when only 10 percent of their ecological “value” has been exploited undermines the entire idea of efficiency that Savory spent his TED talk promoting.

Further weakening Savory’s argument for the wholesale application of holistic management to the world’s deserts is his distorted view of desert ecology. There are two basic kinds of deserts: genuinely degraded landscapes in need of revival and ecologically thriving ones best left alone. Proof that Savory fails to grasp this basic distinction comes when, during his talk, he calls desert algae crust (aka “cryptobiotic crust”) a “cancer of desertification” that represses grasses and precipitate runoff. The thing is desert algae crust, as desert ecologists will attest, is no cancer. Instead, it’s the lush hallmark of what Ralph Maughan, director of the Western Watersheds Project, calls “a complete and ancient ecosystem.” According to the U.S. Geological Survey, “Crusts generally cover all soil spaces not occupied by green plants. In many areas, they comprise over 70 percent of the living ground cover and are key in reducing erosion, increasing water retention, and increasing soil fertility.” Savory, whose idea of a healthy ecosystem is one with plenty of grass to feed cattle, neglects the less obvious flora—such as, in addition to algae crust, blackbrush, agaves, and creosote—that cattle tend to trample, thereby reducing the desert’s natural ability to sequester carbon on its own terms. “It is very important,” Maughan writes, “that this carbon storage not be squandered trying to produce livestock.”

Savory’s most compelling and controversial assumption—one that’s absolutely central to his method—is that humans can viably “mimic” (a word he uses about a dozen times in the TED talk) “all of nature’s complexity.” This is a stunning claim. The conceit of mimicry as a virtue of Savory’s technique is challenged in part by the fact that not all deserts rely on the presence of herd animals for their ecological health. In many desert ecosystems, desert grasses evolved not alongside large animals but in concert with desert tortoises, mice, rats, rabbits, and reptiles. It’s difficult to imagine how a human-managed ecosystem such as Savory’s—dependent on manipulating the genetics of livestock, building sturdy fences, manufacturing supplemental feed, and exterminating predators—is more representative of “nature’s complexity” than a healthy desert full of organisms that have co-evolved over millennia.

In 1990, Savory admitted that attempts to reproduce his methods had led to “15 years of frustrating and eratic [sic] results.” But he refused to accept the possibility that his hypothesis was flawed. Instead, Savory said those erratic results “were not attributable to the basic concept being wrong but were always due to management.” In a favorable interview with Range magazine in 2000, Savory seemed unconcerned with the failure of his method in scientific trials: “You’ll find the scientific method never discovers anything. Observant, creative people make discoveries.”

Understandably, given his adherence to scientifically questionable conclusions in the face of evidence to the contrary, scientific institutions have not gone out of their way to work with Allan Savory. As a result, Savory has built his own institutions. From the Center for Holistic Management (later the Allan Savory Center for Holistic Management) to the Savory Center to Holistic Management International to the Africa Centre of Holistic Management, Savory has kept his ideas in motion. Today, Savory, nearing the end of his career, heads the for-profit Savory Institute. Whether desert landscapes or the foundation’s coffers become any greener remains to be seen. In the meantime, the evidence continues to suggest what we have long known: There’s no such thing as a beef-eating environmentalist.

Slate’s coverage of food systems is made possible in part by the W.K. Kellogg Foundation.