Cattle grazing may restore grasslands and reverse desertification

In a series of lectures, Dr. Allan Savory, a biologist and former Zimbabwean farmer claims that mis-managed cattle grazing, such as has occurred in Africa, has turned grassland into desert, but properly managed cattle grazing can reverse the process, reclaim the desert, and turn it once again into productive grassland.

Savory was a member of the Rhodesian Parliament and had to go into exile after opposing the policies of Ian Smith. In 1992, Savory founded the Savory Institute in Boulder, CO, and the Africa Centre for Holistic Management in Victoria Falls, Zimbabwe. You can watch videos of his 2009 lectures here and a February, 2013, lecture here (22 minutes).

Savory’s basic thesis on grazing is this:

“In the past, large wild herds of herbivores such as caribou and buffalo migrated over the land to find food and avoid predators. These herds grazed, defecated, stomped and salivated as they moved across the grasslands, building soil and deepening plant roots. Once these herds had migrated onward they would not return to an area until it had recovered.”

“Unfortunately, over time, the wild herds disappeared and were replaced by small numbers of domestic, sedentary livestock. Without the timely stomping and excrement of large numbers of animals, the cycle of biological decay in these grasslands was interrupted and the once-rich soils turned into dry, exposed desert land.”

Savory’s solution is to concentrate grazing in small areas and move the cattle frequently. I have seen this method practiced in the Cape Province of South Africa when I was doing geologic exploration there many years ago. There, the land is very flat as shown in my photo. There are miles and miles of miles, as one South African colleague put it.

The Savory setup is to establish a central water source, then encircle it with six to eight, relatively small, wedge-shaped pastures enclosed with barbed wire. Cattle are grazed in one or two of the wedges and moved frequently. This short-term, intense grazing does help restore the grasslands in this area.

Would this method be beneficially applicable to cattle grazing in Arizona? To find out, I consulted a friend who is a cattle rancher in Southern Arizona, an expert on desert grasses, and familiar with the Savory system. The answer is “no” at least in Southern Arizona, because:

The Savory Method is highly intensive, requires enormous expense in mini-pasture fencing and constant moving of livestock. Desertification is certainly a concern in Africa. But here it is of less concern because of our intensively monitored and managed systems (developed largely on the Santa Rita Research Ranch in the Green Valley area by U of A agricultural experts). We manage according to agreement with the Forest Service and State Land Department based on this locally-derived science. Desertification is simply not happening in this area.

The pattern here is larger pastures with rest-rotation systems geared to our bimodal rainfall regime with the primary growth in the summer. Entire summer rest is provided (in fact, about 20 months) every other year on most of our summer pastures. Our herds are generally in one large pasture for a season and then are moved to pastures with forage that has had a significant regrowth period. This process seems to produce the best plant community including wildlife habitat and promotes sustainable or steadily above-sustainable production of herbage with the widest variety.

Our rugged, distant, forest pastures don’t lend themselves to mini-pastures: we’d have to drill many more wells or put in more miles of expensive pipelines. We would also have the problem of maintaining many fences cut by folks moving illegally north. The Savory system may well get good results in flatter, privately owned, access-controlled land, but that is quite different from Southern Arizona ranchland.

We see, therefore, that there is not a universal solution, but great benefit when methods of better practice are designed for local conditions. And in each case examined here, cattle grazing can benefit the environment.

While this result may be surprising to some and contrary to the precepts of radical environmental groups, it is just common sense that cattle growers have an economic interest in keeping the range healthy and productive.

See also:

Buenos Aires National Game Refuge This post gives a history of ranching in the Altar Valley.

Ranching and agriculture in Arizona, The Arizona Experience

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2 comments

  1. A reader reminds me that cattle are also used on ASARCO tailings dumps to help revegetate them to help reduce blowing dust.

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