Can You Trust Fleischner (1994)?

Fleischner, T.L. 1994. Ecological Costs of Livestock Grazing in Western North America. Conservation Biology 8(3): 629-644.

One peer-reviewed journal article that is frequently cited by those who advocate removing all livestock grazing from public land is Fleischner (1994). The article is presented as a review of the scientific literature on livestock grazing in the West.

I’d like to put the article above in context. It was published in 1994, around the time some environmentalists we repeating; “Cattle free by 1993.” The statement was made in reference to removing livestock grazing from all federal public land. That did not happen and Fleischner was published in 1994. In addition, the review is over twenty-years-old. Isn’t there a more recent review that can be cited to make the case all or most livestock grazing is harmful to arid rangelands in the West?

In his article, Fleischner does not discriminate between over-grazing and sustainable grazing. He makes this clear in his letter to the editor in the April 1995 issue of Conservation Biology. In his letter he states: “I explained (Fleischner 1994) why I think the term “overgrazing” lacks clarity; consequently, I think the term should be avoided. I agree that there are valid uses of livestock as a management tool, but as I stated in the article (p. 636), many such claims are suspect.

In terms of sustainable rangeland management, scientists and managers distinguish between over-grazing and sustainable grazing. To label papers about over-grazing, which is usually made clear in the introduction or objectives of an article, as a grazing study is misleading to the reader. I agree that over-grazing is not a sustainable practice and detrimental to any grazing land.

After Fleischner (1994) was published, at least 11 letters to the editor were published in the 1995 April and June issues of Conservation Biology about his review. Some supported Fleischner’s (1994) stance on the livestock grazing. While others stated his paper’s obvious bias “livestock grazing is detrimental” does not belong in a peer-reviewed scientific journal.

In addition, not all scientists agreed with the completeness of Fleischner (1994). Curtain in 2002 reported “A paper by Fleischner (1994) is not discussed here because that paper is generally not considered a comprehensive review of the literature (Brussard et al. 1994; Brown and McDonald 1995; Curtain 1995; Jones 2000).”

Below I present either quotes or summaries from the articles cited above:

Brown and McDonald (1995): “We have three concerns about this review.”

“First, it implicitly assumes that these studies reflect the average impact of grazing and thus its true costs. Examination of the relevant studies, however, reveals that some studies that report little or no livestock impact are not cited. Many studies that are cited suffer from poor experimental design. For example, many studies had problems with pseudo replication or lack of replication. Many study areas were likely chosen because differences between grazed and ungrazed areas were already apparent.”

“Second, many effects of excluding domestic livestock on other organisms and on ecological processes that Fleischner cited have also been observed when native mammals, ranging from rodents to mega herbivores, have been excluded. Such differences between plots where herbivorous mammals are present or absent are often substantial. Both domestic livestock and native mammalian herbivores may remove substantial biomass causing reduced herbaceous and shrubby plant cover, changes in plant and animal species composition, soil disturbance, and alteration of ecosystem processes, but these changes are not necessarily unnatural or detrimental.”

“Third, Fleischner repeats the fiction that the condition of western North America as chronicled by European explorers and colonists represents a natural and inherently desirable state. Changes in landscapes, habitats, and organisms recorded in the last few centuries are measured against an inferred historical condition and usually are regarded as detrimental impacts of human activities. In the absence of direct evidence such as photographs or fossils, determining with certainty past conditions and therefore a natural state, which has often fluctuated much through time, is difficult.” Note: References were deleted from the passage above due to length.

Brussard et al. (1994): While, I can’t find a reference to Fleischner in the article above. The editorial refutes the idea of scientists designing experiments to support the causes of environmental activists.

Curtin (1995):  “I was disturbed by Fleischner’s failure to distinguish between over­grazing and grazing as a management tool. His review of the literature leads one to the implicit assumption that all grazing is bad.”

“…grazing has diverse and varied effects on the local biota.”

“Models by Milchunas et al. (1988) illustrate that one must consider grazing in the context of historical disturbances.”

“There is little doubt that over­grazing is a severe ecological problem. Yet, ecologically responsible grazing can be an important management tool for conservationists.”

Jones 2000:Traditional qualitative literature reviews do little to resolve such controversial issues, as they are subject to biases of the reviewer. For example, Fleischner’s (1994) review of effects of grazing in western North America almost exclusively cites prior studies demonstrating detrimental effects of grazing. A range scientist with a contrary bias could easily cite as many studies demonstrating insignificant, and beneficial, effects of grazing. Though Fleischner’s study sought to make the case against grazing rather than present a comprehensive review of grazing literature, I cite this example to illustrate that literature reviews can sometimes be a front for specific agendas.


  1. Brown, J. H., and W. McDonald. 1995. Livestock grazing and conservation on southwestern rangelands. Conservation Biology 9:1644–1647.
  2. Brussard, P. F., D. D. Murphy, and C. R. Tracy. 1994. Cattle and conservation biology: another view. Conservation Biology 8: 919–921.
  3. Curtin, C. G. 1995. Grazing and advocacy. Conservation Biology 9:233–234.
  4. Jones, A. 2000. Effects of cattle grazing on North American arid ecosystems: a quantitative review. Western North American Naturalist 60:155–164.

How I Critique a News Article

This is how I analyze a news article, at least in my head. I ask questions. I want to know where the information in the article originates. It’s easier to read the original article without my comments. You can connect to it by clicking on its title below. My comments about the article are in bold and italics, and text that I consider opinion is in green.

The article below was written for Wildlife News, and it’s easy to assume that Wildlife News is pro-wildlife. I like wildlife, however, I don’t know their stand on grazing livestock on public lands. I think I can guess, but I’m not sure. I look at the keywords for the article; they are: BLM, Department Of Interior, Economy, Grazing and Livestock, Public Lands. It doesn’t say opinion or commentary so I assume it is news.

Article Title: BLM Public Lands Grazing Accounts for Only 0.41% of Nation’s Livestock Receipts

By Ken Cole On August 15, 2013·In BLM, Department Of Interior, Economy Grazing And Livestock, Public Lands

The recently released Department of Interior Fiscal Year 2012 Economic Report shows that Grazing on BLM Public Lands Accounts for only 0.41% of the nation’s livestock receipts and only 17,000 jobs. In contrast, recreation accounts for 372,000 jobs and contributes $45 billion to the economy.

Comment: The article begins with accurate statements from the Department of Interior (DOI) Fiscal Year 2012 Economic Report. However, I think they should have used the same measure, direct economic output. According to DOI report: “Direct economic output attributable to public land forage for FY 2012 was estimated to be approximately $808 million dollars.” Page 60. $808 millions dollars is still much, much less than $45 billion. Comparisons should be made in the same units.

According to the report, the BLM permits 12.4 million animal unit months (AUM’s) but only about 9 million AUM’s were billed in 2012 and the average during recent years is only about 8 million AUM’s. An AUM is the unit of measure for livestock grazing and equals to forage needed to support one cow/calf pair or five ewes and their lambs for one month. The rate for an AUM in 2012 was $1.35, which in terms of inflation, is lower than it has ever been. As of 2011, the BLM has about 18,700 active permits on more than 21,000 allotments across 155 million acres.

Comment: The DOI report also stated: “The remaining AUMs were not used due to resource protection needs, forage depletion caused by drought or fire, and economic and other factors.” Page 59. This statement is important considering the statements made below about the BLM.


The report goes on to rationalize the reason for the low rates as compared to private grazing lands where the market price was $16.80/AUM in 2011. Public lands are not as productive as private lands and private landlords may provide and maintain other amenities such as water developments or fences for the ranchers. Unfortunately, even with the absurdly low rates, ranchers routinely ignore fence and water development maintenance. (Comment: How many ranchers don’t fix fences or maintain their water development?) On nearly every trip to the field I have made over the years, I witness cattle inside poorly maintained exclosures or sign that they have been there. (Comment: How many trips? Over what area? Which years? Who is supposed to maintain exclosures? What do you mean by sign of cattle?) I also routinely witness water troughs that completely fail or that leak onto the ground creating a stinking, muddy, manure and urine filled mire that is ideal habitat for West Nile Virus infected mosquitos and pollute other surface waters and groundwater. (Comment: Define routinely. What do you mean by completely fail? How many different troughs over what time period?) These same troughs also lack the required bird escape ladders (Comment: All of them, because more and more troughs are being fitted with bird escape ladders) and sometimes are filled with dead wildlife. (Comment: What do you mean by filled? The link goes to the following article: “More Ranching Custom and Culture. Dead Wildlife in Water Troughs. By Ken Cole On August 30, 2011 In Advocacy, Conservation, Public Lands, Western Watershed Project.” So if you follow the link above, you’re sent to an article labeled advocacy and you’re no longer reading news.)

Mountain Springs allotment

The report does admit that the absurdly low grazing rates “creates an incentive to use federal forage before using other forage sources and perhaps to use federal grazing allotments more intensively than privately owned rangeland.” (Comment: I find this statement from the report interesting since agencies determine when and how long livestock are on an allotment.) This is clearly evident when you visit many western grazing allotments. Often, private rangelands are in considerably better condition than our public lands, especially in drought years when permittees often increase their use of public lands except for the rare case when the BLM recognizes the drought conditions. Even then, since there is a large discrepancy between the number of AUMs permitted and the actual number of AUMs used, any cuts to grazing during drought years are only imaginary and use increases over previous years anyway. (Comment: The DOI report includes a graph of AUMs used from 1970 to 2012. The figure caption states: “Figure 8-1 shows the downward trend in AUMs used, from 12.8 million in FY 1970 to less than 9 million in FY 2012.” Page 60. Based on the graph AUMs have decrease— not increased.) This phenomena is occurring this year in parts of Idaho where the BLM and the USFS have failed to make any significant cuts to grazing during a severe drought.

Comment: The text in green font I believe to be either opinion or inaccurate information. None of the information above or below in green is in the DOI Report nor is the word “absurdly”. 

The public lands grazing program among all agencies, according to a General Accountability Office report, cost $144 million in 2005 and received only $21 million in grazing fee receipts.

In contrast, compare the economic benefits to recreation, an activity, generally, that is far less damaging to landscapes and habitats than livestock grazing. Recreation supports 372,000 jobs and contributes $45 billion to the economy. Arguably, livestock grazing greatly reduces the value of a landscape for recreation. With polluted water, degraded wildlife habitat, hundreds of thousands of miles of barbed wire fence that tear clothes, gates that are nearly impossible to open and close, predator killing to protect livestock, aggressive guard dogs, and many other impacts, livestock grazing eliminates or detracts from the value of the landscapes that would otherwise support much more wildlife and unhindered recreation.

When you compare the economic values of one activity over another and then compare the undue political influence that welfare livestock interests have over everything else, it is clear that livestock grazing on public lands is out of place with modern values. The federal agencies that manage livestock grazing on public lands are failing to properly manage livestock and ranchers have subdued them from doing so at the taxpayers’ expense.

The report has a curious error though. A chart contained in the appendix shows the inflation adjusted grazing fee but calculates the value in 2012 dollars incorrectly. Here is the correct data with additional years and data for the USFS, which is part of the Department of Agriculture not the Department of Interior.

Comment: I agree with the authors. The chart doesn’t seem to be correct, which doesn’t give me confidence about using government documents.

Misusing Mueggler

Mueggler (1975) has been cited to further the notion that all livestock grazing causes irreparable harm to plants in arid environments unless plants are rested for years after grazing. Below I give a recent example of authors misusing Mueggler (1975) from the following publication:

Carter, J., A. Jones, M. O’Brien, J. Ratner, and  G. Wuerthner. 2014. Holistic Management: Misinformation on the Science of Grazed Ecosystems. International Journal of Biodiversity.

These authors state: “… bunchgrasses in arid environments are more likely to die if they are heavily grazed by domestic animals [34” AND “Native, western USA bunchgrass species such as bluebunch wheatgrass (Pseudoroegneria spicata) and Idaho fescue (Festuca idahoensis) are sensitive to defoliation and can require long periods (years) of rest following each period of grazing in order to restore their vigor and productivity [34”

Reference 34 is identified in Carter (2014) as: Mueggler, WF. 1975. Rate and pattern of vigor recovery in Idaho fescue and Bluebunch wheatgrass. Journal of Range Management 28:198-204.

Why do I think these statements are misleading? Public land agencies do not condone heavy grazing. Mueggler doesn’t study the likelihood of plants dying from heavy grazing. I couldn’t find any information concerning it in the paper. Defoliation isn’t defined above, but I assume they mean grazing since it is used later in the sentence. However, Mueggler is not a grazing study. It’s a clipping study. Grasses are clipped in or near the boot stage of development, when grasses are most susceptible to both clipping and grazing.

To apply this clipping study to any livestock grazing in an arid environment, one must assume:

  • Clipping and grazing affect plants equally.
  • The species of concern are either bluebunch wheatgrass or Idaho fescue. If not, then all plants respond the same way to grazing.
  • All plants in the community are grazed to the same level of clipping used by Mueggler.*
  • The entire plant, and not just part of the plant, will be grazed.
  • Plants are grazed at or near boot-stage of development.
  • The same climatic conditions that occurred during Mueggler are present.
  • The same history of grazing, that occurred prior Mueggler, exists.
  • Plants grow on the same aspect, slope, and soil type as in Mueggler.
  • Soils have the same nutrient levels as those present in Mueggler’s study.
  • Plants are growing in the same plant community that occurred at Mueggler’s study site.
  • Grazing a plant not in full vigor, which is a very vague term, is detrimental to plants and the grassland as a whole at a landscape level.

*Bluebunch wheatgrass was clipped to remove 50% of the plant by weight. For Idaho fescue, the clipping was so severe that it cannot be equated with any grazing management plan.

The statements made by Carter et al. (2014) ignore grazing studies by Ganskopp and Bedell (1981) in eastern Oregon. They showed that: 1) Lightly (0%-25% utilization) grazed Idaho fescue and bluebunch wheatgrass (BBWG) produced as much or more height, weight, and seed stalks as ungrazed plants; 2) No differences were detected between moderately (25%-70% utilization) grazed and ungrazed BBWG and fescue plants; 3) Heavy grazing (above 70% utilization) reduced production and height of fescue, but did not significantly impact BBWG; and 4) No plants died from grazing treatments.

Also, Rickard et al. (1975) working in eastern Washington concluded that clipping studies do not mimic cattle grazing. They also reported that many years of moderate grazing could likely be sustained before pronounced shifts in plant species composition and abundance, including BBWG, are noticed.

Finally, a clipping study by Clark et al. (1998) discovered plants that when only ½ of their basal area was clipped to a 3” stubble height during mid-boot, it increased their basal area by 18.6%. In comparison, the basal area of unclipped plants only increased by 5.2% by the end of the growing season.


Clark, PE, WC Krueger, LD Bryant, and DR Thomas. 1998. Spring defoliation effects on bluebunch wheatgrass: II. Basal area. Journal of Range Management 51:526-530.

Ganskopp, DC and TE Bedell. 1981. An assessment of vigor and production of range grasses following drought. Journal of Range Management 34:137-141.

Rickard, WH, DW Uresk, and JF Cline. 1975. Impact of cattle grazing on three perennial grasses in south-central Washington. J. Range Manage. 28:108-112