Comments on Allan Savory’s Proposed Application of “Holistic Management” to
Grasslands, Including Desert Grasslands,
for the Purpose of
Increasing Sequestration of Atmospheric Carbon
(Based upon a memo of 2 April 2013 to the Sierra Club authored by Mike Hudak in collaboration with the Club’s Grazing Team members and issued on behalf of the Grazing Team.)
Revised 6 July 2015
Mike Hudak
Summary
Recent widespread interest in Holistic Management (HM), primarily stemming from Allan Savory’s presentation at the February 2013 Long Beach, CA, TED conference, makes it important that Club members and staff be consistent in their response to calls for application of HM. Savory has received considerable attention for his claim that application of HM to husbandry of ungulate livestock (typically cattle) in the world’s grasslands could sequester sufficient atmospheric carbon to reduce atmospheric carbon concentrations to pre-industrial levels. I urge the Sierra Club to reject HM as a tactic to reverse climate change for the following reasons:
1) independent scientific research (in contrast to anecdotes from promoters and users of HM) since the early 1980s has not shown HM to perform better than other grazing management methods,
2) applications of HM have produced mixed results, but in arid regions worldwide have often led to further environmental degradation,1
3) Savory’s characterization of a “desertified” grassland is contradicted by well-established scientific understanding of desert ecology, particularly as regards biological soil crusts, and
4) claims of HM’s widespread ability to increase sequestration of atmospheric carbon have not been independently studied and are
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indirectly contraindicated by recent, peer-reviewed research showing that grazing exclusion in some grasslands actually increases carbon sequestration relative to continued grazing.
Details
Holistic Management (HM) is a general plan for land management promoted by its developer Allan Savory2 under one name or another since the 1970s. The best-known application of HM occurs in livestock husbandry. Most attractive to ranchers has been the claim that through the use of HM, they could greatly increase their production of livestock—doubling it or more.
At the February 2013 Long Beach, CA, TED conference, Allan Savory,3 went further, stating that HM applied to husbandry of ungulate livestock in grasslands worldwide could reduce atmospheric concentrations of carbon to pre-industrial levels. This miracle would supposedly occur through the sequestering of atmospheric carbon that would result from the greater production of vegetation in turn resulting from the grazing of livestock. I question Savory’s claim on several grounds.
Savory proposes using domesticated livestock, such as cattle or sheep, to replicate the behavior of migrating native ungulates in grassland ecosystems. In the desert grasslands of the American West, much of which are managed as federal public lands, large herds of large ungulates in any way resembling cattle have been absent for more than 10,000 years. Consequently, intensive herding of cattle in these regions does not replicate any natural process with which the current native vegetation has evolved.
Savory’s TED talk and the website of his organization (Savory Institute,
http://www.savoryinstitute.com/) provide examples of environmental improvement of ranched landscapes after application of HM. Lacking, though, is independent verification of these claims, without which we cannot know whether such improvement occurred because of HM or coincidentally for other reasons. Sierra Club Grazing Core Team member George Wuerthner in his 2002 book Welfare Ranching4 noted that HM requires much more diligent monitoring of livestock than is typical, particularly for ranching on public lands. The very act of paying greater attention to livestock grazing (and properly responding to on-the-ground conditions) may be the major factor underlying improved environmental conditions.
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Versions of HM have been studied by academic researchers since the early 1980s. Results of many such studies have been compiled into what are called “summary” or “synthesis” papers. Particularly notable are such studies by Skovlin (1987),5 Holechek et al. (1999),6 Briske et al. (2008),7 and Carter et al. (2014).8
In general, these authors did not find support for claims that HM with high-stocking rates benefits cattle and the environment. And when stocking rates were comparable to those of other grazing approaches, performance of HM also was not superior.
Perhaps even more damning of HM than the three articles cited above is one by Joseph et al. (2002)9 which reviewed the Charter Grazing Trials, of which Allan Savory once wrote “The only trial ever conducted proved what I have always advocated and continue to advocate when livestock are run on any land.”10 But Joseph et al. in summarizing these trials stated “Our review of findings from African studies on short-duration grazing including the ‘Charter
Trials’ shows a very high similarity to those from North America summarized by Holecheck et al. (2000).” The Holechek et al. (2000) study (as cited in footnote #6) reports that HM (studied as “short-duration grazing”) performed no better than continuous grazing in regard to water infiltration, soil erosion, plant succession, range condition, forage harvest efficiency, and financial return when stocking rates were comparable. And short- duration grazing actually performed worse than continuous grazing when stocking rates were higher! But although Allan Savory has since the 1970s promoted HM (or its predecessors “Savory Grazing Method” and “Holistic Resource Management”) as the solution to repairing degraded landscapes and increasing the wealth of ranchers, he has now gone one huge step further in his February 2013 TED talk by suggesting that HM applied especially to grasslands of Africa and the Middle East is the only hope for mitigating the causes of global climate change.11 In challenging this claim, I cite peer-reviewed studies that contraindicate using ANY livestock grazing to increase sequestration of atmospheric carbon. For example:
1) That desert biological soil crusts “can be dominant sources of productivity and carbon sequestration in extremely dry environments, and they can contribute to soil fertility through the fixation of nitrogen.”12 These are the same crusts that Allan Savory in his February
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2013 TED talk referred to as a “cancer” on the landscape, the destruction of which he advocated through the grazing of livestock.13
2) A study of Leymus chinensis grasslands of China with exclusion of livestock grazing for 3-yr, 8-yr, 20-yr, 24-yr, and 28-yr found the high- est amount of carbon sequestration in soil and aboveground biomass after 20 years. Study authors conclude “Grazing exclusion for two de- cades increased the soil C [carbon] and N [nitrogen] storage by 35.7% and 14.6% respectively, in the 0- to 40-cm soil layer. The aboveground net primary productivity and soil C and N storage were the highest with 24-yr GE [grazing exclusion] and the lowest with free grazing.”14
3) A study of a semi-arid grassland in China found “the C stocks in aboveground biomass, belowground biomass and litter were 70–92% (P<0.01), 56–151% (P<0.01) and 59–141% higher (P<0.01), respec- tively, in grazer excluded grassland than in grazed grassland. Grazing exclusion significantly increased C and N stored in plant biomass and litter and increased the concentrations and stocks of C and N in soils. Grazing exclusion thus significantly increased the C and N stored in grassland ecosystems. The increase in C and N stored in soil contrib- uted to more than 95% and 97% of the increases in ecosystem C and N storage. The highest C and N stocks in ecosystems were observed in 17-year grazer excluded grassland.”15
4) An Australian study found that “d e s t o c k i n g c u r r e n t l y g r a z e d s h r u b l a n d s f o r t w o d e c a d e s r e s u l t e d i n a n e t C a c c r e t i o n , o v e r 2 0 y e a r s , i n t h e o r d e r o f 6 . 5 M g/h a , a l m o s t e n t i r e l y t h r o u g h i n c r e a s i n g b e l o w g r o u n d C . ” |