Monday, November 3, 2008

Do rangelands need to be grazed?

Here's a response I wrote to a student who had read my Is Ranching Sustainable article and challenged me suggesting that since bison once grazed the West, our rangelands "need" to be grazed. It's a common argument, and one heard often from ranching advocates. His original email to me is below my comments.

Alex:

Thanks for writing. Glad to see you are thinking about these things to some degree and that you are curious enough to look at it further. I think if you look into this issue more, you might find that the conclusions need greater refinement.

You raise the point about cattle replacing bison. I have an article on my blog (Wuerthner on the Environment) about that issue and it goes into more details, but bison are no more the same as cows as polar bears are the same as black bears--though obviously they are related. Cattle evolved in moist woodlands (like Georgia or Alabama) in Euro Asia. They have a host of evolutionary features that makes them unsuitable for western rangelands. Bison on the other hand have many features that makes them better adapted to the arid west. For instance, bison move all the time--whether they run out of food or not. They naturally spread their grazing impact over a much larger area. The hump gives them a fulcrum point that permits them to canter for long distances with little energy out put. Cattle are far less mobile not to mention that we have bred them to be fat and lazy. Bison can digest much less nutritious forage than cattle meaning they don't need hay produced by drawing western rivers for irrigation. Bison are better able to fend off predators meaning we don't need to kill predators like wolves because bison are perfectly capable of defending themselves. Etc. etc. etc.

So the assumption that we can replace bison with cattle is like suggesting that if polar bears were driven to extinction, we could move a bunch of black bears up to the ice floes and they would figure out to survive and eat seals. The only way we could raise black bear on the polar seas is with huge subsidies--both environmentally and economic--which is the only reason that ranching survives in the West.

But beyond that point, you may not be aware that most of the West's public lands were never grazed by large herds of grazing animals. Bison were found all the way to the East Coast, but they were seldom found west of the mountain front in the West. I.e. they were found on the plains of Colorado, Wyoming, Montana, etc. but not beyond. Most of the public land in the West lies west of the mountain front in Nevada, Idaho, Utah, Arizona, eastern Oregon, California, and so on. There were no large herds of bison in these places. (There are a few exceptions to this which again I won't get into here, but as a generalization, most of what is now public lands was outside of the normal range of bison. So cattle are not replacing bison, and more importantly, the plants that live in these parts of the West do not tolerate grazing pressure.

The Great Plains is a different story, but that is not where the bulk of public lands allotments are located.

Third, even at the levels of stocking that are done today, ranching isn't surviving in this region. What is surprising to most people to learn is that most of our beef is not produced in the West, and particularly not on public lands, but in the East. Virginia produces more beef than Wyoming--the Cow Boy State, and Florida has more cows than New Mexico, Arizona, Utah and Nevada combined. There is more beef raised in tiny Vermont than on all the public lands in Nevada. The reason? The West is a very unproductive place, particularly the public lands. These are generally the driest, most rugged, and least productive lands in America. You can feed a cow on a few acres in Georgia that would require several hundred acres of land in dry Nevada to sustain the same cow.

The point is that the West is too arid to support economically viable livestock production. Even the private lands in the West--which on the whole are more productive than public lands, can't sustain viable ranching operations. And that was the major point of the essay you read.

Now to your other point that these lands "need" to be grazed. What you will find is that most rangeland plants "tolerate" some moderate amounts of grazing. But keep in mind that there are all kinds of animals grazing on the grasslands whether there are cows on out there or not. For instance, in Yellowstone Park (where there are no cows) you have elk, bison, etc. grazing the plants. But surprisingly these animals are not the most important grazers on the plants. Grasshoppers and nematodes consume far more of the grass biomass than any of the larger animals. In most grasslands, even among mammals, small rodents like ground squirrels and prairie dogs (where they are not poisoned and killed by ranching interests) consume far more of the biomass than larger animals. We are so focused on the big animals that we forget that in most ecosystems, it's the small creatures that are really important. Even if there were not a single elk or bison in Yellowstone, the grasslands would be grazed. So the idea that we need cows to do something to those grasslands is absurd. Grasslands are grazed all the time, just not by cattle.

And there are important ways that these other grazers use the landscape that makes them far superior to domestic livestock. One can't assume that we can replace grasshoppers and ground squirrels with cattle and everything is hunky dory.

Please keep in mind that most range literature whether read by Michael Pollan or you is produced by range departments which have a vested interest in promoting livestock. So you have to look carefully at their studies. For instance, I recall a number of studies that purported to show that livestock grazing "improved" riparian areas. What the studies compared were areas grazed by high stocking rates of cattle with areas with fewer cattle. The areas with fewer cattle "improved". The range study proclaimed that "grazing improved riparian areas."

What the studies really showed is that less grazing was better, and other studies have shown that no grazing is even better than less grazing in terms of riparian area health. But these range professors did not have a control (a typical defect of range studies). It would be like a tobacco company showing that those who smoked one pack of cigarettes a week had less chance of lung cancer than those who smoked three packs a week, then suggesting that smoking could lead to improved health.

Keep in mind that response is not the same as benefit. In other words, grasses will grow more above ground biomass if cropped whether by a bison, cow or grasshopper. But that doesn't mean they "need" to be cropped. Typically range studies only look at the above ground parts of a plant because that is what they are interested in since that is what cows eat.

In fact, if the above grass biomass is cropped a lot there is a loss of biomass in the roots--making such plants more vulnerable to droughts--this is one of the reasons that livestock grazing can cause so called "overgrazing". The plants don't die directly from grazing. They disappear gradually because grazing by livestock diminished their root system, and eventually a drought killed them.

So this is an issue about what you are measuring. Is above ground biomass the appropriate measurement of "grassland health?" Well to the rancher it is important because they want more grass for their cows--so most range scientists focus on measures of this kind of thing. And at the same time, they typically ignore the loss of root biomass because that doesn't favor grazing by cows--which after all is what they see as their mission.

Let me give you another example of how not only what you measure, but how you interpret things affects your conclusions. I can show you lots of studies that show that if you kill coyotes they will respond by having more pups. Does that mean coyotes "need" to be shot, poisoned and trapped? Hardly. It just means they can cope with a certain level of exploitation. But I assure you that coyotes do just fine without being killed all the time by humans. They don't "need" to be killed. Yet if your goal was "production" of more coyotes, than you might conclude that coyotes need to be shot, trapped, and poisoned, since in the end this would produce more biomass of coyotes.

If you are really interested in learning more about this so you can have a more informed perceptive, I might suggest you visit my web site where I have at least some articles that address these and other issues.

Thanks for writing.

Alex Aizenman wrote:
> Hi George,
>
> I am sitting in my primate social behavior class at the moment, Which happens to be an incredible waste of time, So I took to scanning the Counterpunch website for some interesting articles to pass the time and I have just read your most recent output to the site, "Is Ranching Sustainable." Just from reading the title I knew what I what you were going to say- Ranching is most definitely not the future of public lands in the west. I am sorry to inform you, but I am really disappointed in your article and your conclusions about ranching. Ranching must must must be the future of western rangelands, for the lands health and our own.
>
> It is incredible to me, that such an educated person such as yourself is seemingly unaware of what many people are doing with their alloted public lands in the west, most importantly, what they are doing to it with the use of cows. Obviously you are correct in saying traditional ranching practice is unsustainable. We all know that (barring those traditional rancher perhaps, but they will know it soon enough). What you are not considering is that Rangeland is MEANT to be grazed. Our rangeland is evolved to have large grass eating ruminants on it, Most specifically- Buffalo. There is a symbiotic relationship we have got going on here- grass need grazers, grazers need grass. You remove part of that equation your going to get unhealthy land, and in this case the continued dessertification of west. It is a myth that if you leave land alone it will gain its maximum health potential. Read anything about holistic resource management and you will learn more.
>
> Anyways, So we got all this grassland or potential grass land but we ain't got the buffalo anymore. Well we got cows (which have been in th west for over 300 years). We can use these cows to our advantage and to the lands advantage as long as we do so with out violating certain rules, namely the rule of the second bite- you can read Michael Pollan for that one (or Joel Salatin for that matter). Just read anything by Allan Nation, Joel Salatin, or you can email eschewennessen@gmail.com and they will tell you everything you need to know, way better than I can about the importance and potential of ranching and holistically managed grazing. Humans can actually make the land better by intensive management ( hard to believe I know).
>
> As an environmental Science student at the University of Michigan, I have seen the limitations of traditional environmentalists and scientists with their leave the land alone and keep people out of nature mentality, as well as their reductive and break-down-the-world-in-to-manageable-parts scientific processes. If you really think there is a viable future in that I am sorry, But their ain't. Kids and students and old old people have to learn that we are part of nature, we have a role, we are all interconnected We will never break down nature into natures individual parts and think we can understand it that way. We have to look at the whole. What better future could you imagine than people getting back in touch with the land, becoming Holistic ranchers and farmers. That is the best future I can imagine right now and What I personally aim to do, And I sure hope there is some land that I can use to do it.
>
> Not to mention that holistically raised beef means healthy grass, healthy cows and healthy you.
>
> Thanks,
>
> Alex Aizenman

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