Article

A global assessment of Holistic Planned Grazing™ compared with season-long, continuous grazing: meta-analysis findings AFRICAN JOURNAL OF RANGE & FORAGE SCIENCE

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Abstract

It has been claimed that Holistic Planned Grazing™ (HPG), a type of rotational grazing, can increase productivity in rangelands and reverse climate change while doubling the stocking rate, mainly through the impact of densely bunched animals on primary production. Previous reviews have found similar or greater plant and animal production in continuous (season-long) compared with rotational grazing. Here season-long continuous grazing is compared with HPG alone to explore the evidence for animal impact. Three quantitative meta-analysis models were used to assess data sets from literature between 1972 and 2016. Weighted mean differences (effect sizes) between HPG and continuous grazing showed that there was no difference in plant basal cover, plant biomass and animal gain responses (p > 0.05). Thus, from the balance of studies, if animal impact is occurring during HPG, it has no effect on production. As interesting as the overall result is the significant between-study heterogeneity assessed using Cochran’s Q (p = 0.007 to <0.0001). Studies with positive effect sizes tended to have higher precipitation (p < 0.05), suggesting that only some rangelands have the resources to support HPG. Furthermore, there is scope for investigating the impact of HPG on socio-ecological aspects of rangelands, such as management.

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... Numerous terms have been used to describe potential components of regenerative grazing (RG) and landholders may use one or more approaches at different parts of their property over different time periods. Some of the terms include spelling or strategic rest (Ash et al. , 2011, rotational grazing (Briske et al. 2008), time controlled grazing (Sanjari et al. 2008), intensive rotational grazing (Badgery 2017), short duration rotational grazing , cell grazing (McCosker 2000;Richards and Lawrence 2009), Holistic Management or Holistic Planned grazing (Savory 1983;Hawkins 2017;Gosnell et al. 2020) and adaptive multi-paddock per herd grazing (Teague and Kreuter 2020), to name a few. Many of the principles outlined in RG are the same as those applied in more traditional bestpractice grazing land management (GLM) approaches, and many of the terms used are common to grazing systems and management generally. ...
... The large number of terms used to describe RG components can be confusing, and it can be difficult to determine whether there are differences in the various approaches, or whether they are simply the same thing with a different name. Either because of the differences in epistemology and nomenclature (Gosnell et al. 2020), or the diverse landscapes on which these practices have been applied, there has been considerable controversy regarding the relative benefits of these methods for grazing production, soil and land condition, and ecosystem function (Abdel-Magid et al. 1987;Hart et al. 1993;Briske et al. 2008Briske et al. , 2011Briske et al. , 2014Teague et al. 2013;Hawkins 2017;Hawkins et al. 2017;Teague and Barnes 2017;Teague and Kreuter 2020). It is not the intention of this paper to focus on the detailed management activities employed because there are several recent reviews of this topic and readers are encouraged to access this literature for more detail (e.g. ...
... For example, de Villiers et al. (2014) found that farmers practicing Holistic Management™ had a higher social capital in that they participated more in groups, which is likely to lead to increased learning and adaptive behaviour. Thus, the farm-level benefits besides production, i.e. socioecological aspects, should be included in future research on production rangelands (Hawkins 2017). Landholders involved in this study also suggested that there are long-term financial gains to be made from these approaches, and a targeted economic analysis to quantify the gross marginal gains would be highly beneficial. ...
Article
Regenerative grazing, which generally involves some form of rotational grazing with strategic rest, is increasingly seen as a profitable management approach that will accelerate landscape recovery. However, there is limited quantitative evidence supporting the benefits of this approach in northern Australia. This space-for-time study collected vegetation and soil data from a range of properties in the Burdekin catchment in Queensland that have implemented regenerative grazing strategies for between 5 and 20 years. Data were also collected at adjacent control sites that did not undergo regenerative grazing, but where more traditional continuous set-stocking grazing approaches were applied. Coincident data were also collected from several sites where grazing had been excluded for ~30 years. Data suggested that improvements in vegetation, soil and land condition can be obtained from implementing regenerative grazing principles, although it is likely to take at least 3–5 years, and up to 15–20 years for statistically significant improvements to be measurable at a site, particularly for areas that are moving from a degraded baseline condition. Vegetation attributes such as plant biomass and basal area and litter incorporation all appeared to be better surrogates than percentage ground cover for representing improved landscape condition and soil health. Sites that maintained remotely sensed percentage ground cover at or above the minimally disturbed reference benchmark levels for >10 years, as well as having statistically higher biomass, basal area and litter, had significant increases in total nitrogen (TN) and soil organic carbon (SOC) relative to the local control site. Although there are indications that regenerative grazing can lead to improvements in land condition, this study does not enable us to conclude whether regenerative grazing will accelerate improvements compared with other best-practice grazing land management (GLM) approaches, and further research on the social and economic dimensions of regenerative grazing is needed.
... However, replicated empirical assessment of the ecological consequences of AMP grazing is limited to studies small in scale and with treatments having more restricted adaptivity compared to actual working ranches (Teague et al., 2013). Although there exists some evidence that in certain climates, AMP grazing is associated with increased aboveground production, its influence on plant diversity is largely unknown (Hawkins, 2017). This knowledge gap is due to both the generality of theoretical frameworks explaining grazing effects on plant communities (i.e. the intermediate disturbance hypothesis, Connell, 1978), and the overall lack of empirical tests of such conceptual theories linking grazing effects to ecosystems. ...
... grazing disturbance, grazing system, intensive grazing, introduced species, native species, plant community, plant diversity (Hawkins, 2017). Even if AMP grazing does not lead to increases in grazing intensity, its underlying intent of causing uniform grazing within each paddock is expected to modify plant heterogeneity and associated diversity. ...
... Grey lines connect paired ranch points, illustrating total directionality of response to grazing management per area per time (Sherren & Kent, 2019), the equivalent stocking rates is understandable. From a social standpoint, AMP grazing is often publicized as enabling higher stocking rates (Hawkins, 2017), though such differences in stocking rates were not found in this particular study. This contrast between expectation and application highlights the value of measuring potential environmental consequences of modified grazing systems from working, rather than hypothetical, cattle operations (Venter et al., 2019). ...
Article
Grassland plant community structure and function are dependent on the type, timing, frequency and intensity of disturbance. Grazing systems employing dense herds of livestock for short periods of time (e.g. Adaptive Multi‐paddock Grazing; AMP) are gaining popularity as a potentially sustainable practice. Effects of AMP systems on plant diversity and composition are unknown, though theory provides some expectations. Spatially homogeneous grazing used by AMP may be a uniform ecological filter, thereby lowering plant diversity; alternatively, the AMP practice of using multiple paddocks might enhance habitat heterogeneity. Maintaining plant diversity, particularly of native species, is a key aspect of sustainability. As such, an understanding of the real‐world effects of AMP grazing is needed. We studied grasslands within 18 pairs of ranches across the northern Great Plains. Ranches managed under AMP were paired with a neighbouring ranch (N‐AMP) using regionally representative grazing practices. We collected surveys of management practices and conducted 2 years of on‐farm sampling to identify plant composition and diversity. Ranch management practices used by self‐identified AMP ranchers differed significantly ( p < 0.1) from those used on neighbouring ranches, with higher stocking densities (number of animals per area at a single time) but not stocking rates (total number of animals per unit time per area) on AMP relative to N‐AMP ranches. There were fewer plant species in AMP grasslands at both the plot and landscape scales compared to N‐AMP ranches despite no overall difference in plant community composition. Management type did not alter the variability of plant community composition (beta diversity) or plot‐level species evenness. Although there were trends for lower diversity of native and introduced species at both spatial scales, a significant effect was found only for native species at the landscape scale. Synthesis and applications . The impacts of AMP grazing system management were limited to a minor reduction in plant diversity, with a modest decline in native species richness. We conclude that the benefits of AMP grazing in the northern Great Plains do not include the maintenance of plant diversity, and this system could hinder the conservation of remaining native plant species.
... Scientific studies find no grounds for the claims of increased production or soil organic carbon (SOC). Indeed, claims for the benefits of rotational grazing (including HPG), have been challenged since the 1950's (Sampson, 1951) and more recently by many studies and references therein (O'Reagain and Turner, 1992;Briske et al., 2008Briske et al., , 2011aHawkins, 2017;Venter et al., 2019aVenter et al., , 2019bVenter et al., , 2020. However, proponents of HM criticize the small scale of some studies, stating that benefits only emerge on large, working livestock farms / ranches (Teague et al., 2013). ...
... Based on abstracts and full texts, peerreviewed articles were selected that compared HPG and other patterns of grazing at defined stocking rates, or more broadly assessed management of mammalian herbivores on production, climate and society, with a focus on farm-scale studies. The aim was not to conduct a metaanalysis of agricultural-style trials that tested how HPG influences production as this has been previously conducted (Hawkins, 2017) while too few studies about HPG and climate or social studies exist. The studies encompassed a range of locations globally, livestock and wildlife types, and grazing management types that were adaptive or not ( Table 1). ...
... Claims about increased production and climate resilience with HM are unfounded based on farm-scale studies, which are also supported by many experimental trials and reviews (Briske et al., 2011a;Hawkins, 2017). This is not surprising because Venter et al. (2019b) found that animal behaviour (time spent grazing, walking or resting; proximity to one another, dung trampling, and selectivity at plant scale) did not differ. ...
Article
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Holistic Management (HM) is claimed to increase production of plants and animals while also increasing soil organic carbon under all conditions in all habitats. Peer-review literature does not support these claims, but several studies report social benefits. Proponents of HM have criticized the small-scale of some studies (less than 2 ha), stating that production and climate benefits only emerge on large working farms (2–66 ha or larger, our size definitions). Here we summarize the conclusions from 22 peer-reviewed studies, focusing on farm-scale studies, and the few social and soil carbon studies from across the globe. Conclusions were synthesized into a diagram showing how grazing pattern (or density), stocking rate and animal type influence biology, climate resilience, and agricultural economics, as well as how HM’s management component affects society. This synthesis confirms that HM’s intensive grazing approach either has no effect or reduces production, as evidenced by farm-scale studies in United States of America, Argentina and South Africa, thus negating the claim by HM proponents that there is a difference between ‘the science and the practice’. Seven peer-reviewed studies show that the potential for increased carbon sequestration with changed grazing management is substantially less (0.13–0.32) than the 2.5–9 t C ha⁻¹ yr⁻¹ estimated by non-peer-review HM literature. Five studies show that HM provides a social support framework for land users. The social cohesion, learning and networking so prevalent on HM farms could be adopted by any farming community without accepting the unfounded HM rhetoric, and governments could allocate funds to train extension agents accordingly. A future focus on collaborative adaptive farm management and other innovations will be more helpful than any further debate about grazing density.
... Given the inherent complexity of grazing strategies available, varying perspectives exist on whether, when, and how variation in grazing alters grassland function. For example, several studies conclude that the benefits of rotational grazing for maintaining grassland production and range condition may not be as large and consistent as previously thought, with the majority of studies reporting no difference between areas subject to rotational and continuous grazing ( Holechek et al. 1999 ;Briske et al. 2008 ;Hawkins 2017 ). In contrast, McDonald et al. (2019) concluded that strategic rest appeared capable of enhancing ground cover and anhttps://doi.org/10.1016/j.rama.2021.04.010 1550-7424/© 2021 The Society for Range Management. ...
... What remains unclear is the extent to which variation in nuanced grazing practices among these cattle ranches regulates grassland responses, such as the length of grazing or subsequent rest periods ( Heitschmidt and Taylor 1991 ). Advocates of AMP (and holistic) grazing highlight the need for high stock densities (i.e., animals per unit land area) for short periods at the optimal time during the growing season to maximize benefits ( Savory and Butterfield 1999 ;Teague et al. 2011Teague et al. , 2013, a response that can vary with environmental conditions ( Hawkins 2017 ). ...
... Given this result, it would appear that the use of individual grazing metrics may be a superior means to characterize the real-world variance in management practices used by cattle ranches, particularly in comparison with the nominal classes of "AMP" or "n-AMP." This finding, coupled with high environmental variability, might explain the difficulty of generalized "systems type" research in detecting significant effects in field studies (Hawkins et al. 2017). ...
Article
Significant interest exists in the potential for specialized grazing systems, including adaptive multipaddock (AMP) grazing, to enhance grassland health and function. However, specific pasture management practices associated with AMP grazing at the ranch level remain poorly understood in comparison with more regionally representative management systems. As part of a larger study examining grazing effects on soil carbon, greenhouse gases, and other ecosystem attributes, here we report on differences in disturbance history and grazing management practices on a sample of AMP operators and their neighboring (n-AMP) ranches at 32 paired sites across the prairie provinces of western Canada. Most ranches studied (77.5%) relied on pastures composed of introduced (seeded) forage. On average, the AMP ranches surveyed were larger in size, supported greater animal numbers, and were more likely to use seeded forages comprising diverse mixes. Relative to n-AMP ranches, AMP ranches used 18.6-fold higher average stock densities in smaller paddocks (22.3 vs. 120.7 ha) while grazing over a grazing season that was 76 d longer, although computed stocking rates remained similar (P ≥ 0.10). AMP operators specifically used much shorter grazing periods (2.8 d) during the early growing season (i.e., before August 1) that were followed by a prolonged rest period (69 d) and could be used to compute a rest-to-grazing ratio for the first half of the grazing season for all ranches. This ratio, along with cattle stock density computed at the pasture scale, exhibited the greatest potential to differentiate the two groups of ranchers. Finally, both groups, and in particular ranchers within the AMP group, demonstrated high variability in management practices among individual operators, highlighting the importance of using specific management metrics rather than generalized descriptors of “grazing system type” to interpret their influence.
... Purported benefits of grazing at increased stocking density over shorter time frames include increased uniformity of forage utilization within a pasture (i.e., less selective grazing by animals), longer intervening periods of pasture rest (nongrazing), increased production of palatable forage species, and greater heterogeneity of vegetation structure among pastures ( Teague et al. 2013 ). Syntheses of numerous experiments examining rotational grazing strategies based on fixed schedules (i.e., nonadaptive decision making) have not shown benefits of rotational grazing to forage or livestock production ( Briske et al. 2008 ;Hawkins 2017 ). We recently compared livestock production under continuous, seasonlong grazing versus multipaddock rotational grazing implemented using an adaptive approach and found that cattle in the latter treatment gained 12 −16% less weight each year . ...
... Second, managers who increase stock densities and rotate cattle among pastures often also employ adaptive management when designing rotation sequences and decision triggers for herd movement. Therefore ranch-scale responses of forage and livestock production to changes in stocking densities are often confounded with the degree to which managers monitor changing conditions and modify management actions ( Teague et al. 2013 ;Hawkins 2017 ;Augustine et al. 2020 ). Consequently, past experimental grazing research might not have demonstrated the purported benefits of rotational grazing because the adaptive decision making of an experienced manager had been excluded ( Briske et al. 2011 ). ...
... Our results suggest that the benefits of CAM as applied to multipaddock rotational grazing arose from the Stakeholder Group's ability to incorporate adaptive movements of livestock across a spatially and temporally variable landscape, rather than the simple alternation of grazing and rest ( Briske et al. 2008 ;Hawkins 2017 ). Relative to a nonadaptive approach, and excluding drought conditions, CAM's increased livestock production at the high stocking density was a direct outcome of its unique decision process bolstered by knowledge of varying soil types, ecological sites ( Reynolds et al. 2019 ), and plant communities in this landscape. ...
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Collaborative adaptive management (CAM) is hypothesized to benefit management of rangeland ecosystems, but the presumed benefits have seldom been quantified, and never in a multipaddock rotational grazing system. Here, we evaluated average daily weight gain (ADG) of livestock (kg steer⁻¹ d⁻¹) in four grazing management treatments during the summers of 2016−2018 in a semiarid shortgrass steppe. These four treatments had the same stocking rate but differed in stocking densities. The three lowest stocking densities were implemented using nonadaptive grazing management, while the highest stocking density was implemented using CAM by an 11-member Stakeholder Group. Three of the four treatments used multipaddock rotational grazing. Growing season precipitation varied from drought in 2016 to near average in 2017 and dry in 2018. During nondrought years, ADG under nonadaptive grazing declined linearly as stocking density increased from low to high. This relationship was not significant during drought (2016). CAM increased absolute livestock production by 0.13 to 0.19 kg steer⁻¹ d⁻¹ in nondrought years, or a 23−25% relative increase in ADG. This benefit of CAM arose from the Stakeholder Group's ability to rotate cattle in response to spatiotemporal heterogeneity across the landscape—i.e., the ability to graze the “right pastures at the right time.” Multiplying the additional grazing season livestock gains achieved through CAM by the monetary value of gains ($ kg⁻¹) resulted in an estimated additional gross revenue return from CAM of $48.16 to $55.54 per steer annually, as compared with revenues from nonadaptive multipaddock rotational grazing under nondrought conditions. These results indicate that CAM, supported with substantial and timely monitoring data, can minimize decreases in livestock production associated with high stocking densities used in multipaddock rotation systems. However, in this experimental context, the economic benefits of increased livestock production associated with CAM were likely insufficient to offset the substantial cost of this approach.
... A major driver of the effects of grazing management on production and soil carbon is growing season length, as driven by climate [56,57]. Longer growing seasons with higher temperatures, at least up to 15 • C MAT, and higher rainfall allow greater opportunity for forage to regrow after grazing episodes. ...
... Climate drivers of grazing management effects on soil carbon followed similar patterns (Figure 7) with very little change in SOC expected under SDHSD schemes as compared to continuous grazing except at near maximum stocking densities ( Figure 8). These outcomes support recent results that suggest greater benefits for SDHSD grazing in more productive grasslands [56,57]. ...
... Context dependence may also explain discrepancies in experimental results and expert opinions about the general benefits of rotational grazing. For example, experiments may not detect benefits of SDHSD schemes because they are mostly conducted at moderate densities for continuous grazing conditions [57]. These moderate densities allow the experiments to separate the influence of grazing scheme from the influence of stocking density but avoid densities meaningful to producers and that SDHSD schemes can support but would cause degradation under continuous grazing. ...
Article
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Soil carbon pools remain a target for sequestering greenhouse gases, but appropriate land management options to achieve such sequestration remain uncertain. Livestock grazing can have profound positive or negative effects on soil carbon. Different models for assessing the influences of grazing are available, but few explicitly account for different management options on soil organic carbon (SOC). Here, I link a previous simple SOC dynamic model (SNAP) to a recent model of episodic grazing and its effects on primary production. The resulting combined model, called SNAPGRAZE, assesses the potential effects of grazing management on SOC across a range of climates with only eight climate, soil, and management input variables. SNAPGRAZE predicts that, at high stocking densities relative to those sustainable under continuous grazing and at higher mean annual temperature and precipitation, short-duration, high stocking density (SDHSD) grazing schemes can enhance forage production and increase stocks of soil organic carbon. Model predictions for current SOC, given a known 50 year grazing history, agrees well with data from nine private ranches in the North American Great Plains. SNAPGRAZE may provide a framework for exploring the consequences of grazing management for forage production and soil carbon dynamics.
... Views are contested on the effects of livestock grazing on soil C. Some recent studies show a decrease (Su et al. 2005;Zuo et al. 2008;Mofidi et al. 2012;Hawkins 2017), neutral effects (Sanjari et al. 2009;Allen et al. 2013b;Booker et al. 2013;Sanderman et al. 2015;Aynekulu et al. 2017) or an increase in soil C (Reeder and Schuman 2002;Teague et al. 2011;Li et al. 2011;Waters et al. 2017b;Orgill et al. 2017). These inconsistencies may be due to differences in plant species composition (Piňeiro et al. 2010); the carry-over effects from previous management or interactions between these factors; inherent variability in SOC (Sanderman et al. 2015) as well as the length of growing season. ...
... The amount of bare ground will increase and cover of cryptogram and litter will decline with high grazing intensity Tabeni et al. 2014;Waters et al. 2017a), but where grazing management incorporates periods of rest, ground cover as well as the perennial pasture component has been shown to increase (Sanjari et al. 2009;Kahn et al. 2010;Teague et al. 2011) in addition to reducing soil erosion (Sanjari et al. 2009). A meta-analysis using 75 studies (Argentina, Australia, Canada, USA and Zimbabwe) compared grazing system impacts on ground cover and livestock production (Hawkins 2017). Holistic Planned Grazing (HPG) (high intensity/short duration grazing) was compared with continuous grazing in temperate and tropical grasslands, savannas and shrublands. ...
... Holistic Planned Grazing (HPG) (high intensity/short duration grazing) was compared with continuous grazing in temperate and tropical grasslands, savannas and shrublands. No differences in ground cover (basal plant cover) or livestock production were found between grazing systems (Hawkins 2017). Although the author noted that areas of higher productivity (generally higher rainfall) tended to have positive effects, overall stocking rate and grazing pressure were found to be more important than the grazing system in achieving a balance between plant and animal production. ...
Article
Demonstrating sustainable land management (SLM) requires an understanding of the linkages between grazing management and environmental stewardship. Grazing management practices that incorporate strategic periods of rest are promoted internationally as best practice. However, spatial and temporal trends in unmanaged feral (goat) and native (kangaroo) populations in the southern Australian rangelands can result land managers having, at times, control over less than half the grazing pressure, precluding the ability to rest pastures. Few empirical studies have examined the impacts of total grazing pressure (TGP) on biodiversity and resource condition, while the inability to manage grazing intensity at critical times may result in negative impacts on ground cover, changes in pasture species composition, increased rates of soil loss and reduce the ability for soils to store carbon. The widespread adoption of TGP control through exclusion fencing in the southern Australian rangelands has created unprecedented opportunities to manage total grazing pressure, although there is little direct evidence that this infrastructure leads to more sustainable land management. Here we identify several key indicators that are either outcome- or activity-based that could serve as a basis for verification of the impacts of TGP management. Since TGP is the basic determinant of the impact of herbivory on vegetation it follows that the ability for rangeland pastoral management to demonstrate SLM and environmental stewardship will rely on using evidence-based indicators to support environmental social licence to operate.
... In an attempt to disprove Savory's theories, critics point to the robust body of experimental evidence that intensive rotational grazing does not increase plant and animal production or enhance surface soil hydrology or improve plant community composition compared to continuous grazing under otherwise similar conditions (Painter and Belsky 1993;Patten 1993;Oliva et al. 1998;Briske et al. 2008Briske et al. , 2011Bailey and Brown 2011). Recently, Hawkins (2017) conducted a meta-analysis on studies comparing rotational grazing and continuous, seasonal grazing to retest Briske et al.'s (2008) findings; she found that HPG did not impact production. As mentioned above, the problem with this work is that intensive rotational grazing is not the same as HPG. ...
... In addition to pointing to results of rotational grazing studies, critics also reason that there is too much bioclimatic variability among rangelands (i.e. mesic vs. arid/semi-arid) to legitimize across-the-board conclusions and prescriptions regarding the superiority of a given grazing approach, such as with fragile Southwest desert crusts (Briske et al. 2013;Goodloe 2013;Hawkins 2017); but HPG advocates argue that since HPG is context-specific and focused on managing complexity, they do not endorse across-the-board prescriptions, so these criticisms may not be relevant. ...
... Briske et al. (2008) argue that a wellmanaged rotational system would have higher production rates than poorly managed continuous grazing, but the converse would also be true; the more productive system would be the one with better management. As such, HM critics argue that the ecological benefits enjoyed by HM practitioners cannot be causally linked with a specific grazing technique; rather, they are more likely the result of adaptive management more generally (Briske et al. 2013;Hawkins 2017). Hawkins (2017) states that given the farm-level benefits, future research on production rangelands should examine social-ecological aspects (see also Brunson et al. 2016). ...
Article
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Holistic Management (HM) is a decision-making framework based on triple bottom line thinking and a proactive approach to managing complexity. Primarily associated with an approach to managing livestock, it has spurred long running and still unresolved debates in rangeland ecology and management. Less studied are the social, cultural, and psychological aspects of HM, which may hold the key to successful ecological outcomes. In this article, we describe the main tenets of HM as conceived by wildlife biologist Allan Savory and address the longstanding and unresolved controversy over its legitimacy. We then provide a meta-analysis that not only provides an up-to-date review of the multidisciplinary evidence and ongoing arguments about HM, but also provides a novel explanation for the controversy—that it is grounded in epistemic differences between disciplines associated with agricultural science that rule out any chance of resolution. We conclude that the way to resolve the controversy over HM is to research, in partnership with ranchers, rangeland social-ecological systems in more holistic, integrated ways. This can account for the full range of human experience, co-produce new knowledge, and contribute to social-ecological transformation.
... They further suggested that stocking rate, rest period, and livestock exclusion may represent the best management strategies for restoring native grassland productivity, ecological condition, and sustainability. Hawkins (2017) reported that holistic management is a goal-setting process that may be used to define quality of life, form of production, and a future resource base for the landowner. It was concluded from peer-reviewed publications that holistic management, also termed holistic planned grazing, does not improve production; thus, this management approach does not warrant the additional inputs of infrastructure and labor. ...
... It was concluded from peer-reviewed publications that holistic management, also termed holistic planned grazing, does not improve production; thus, this management approach does not warrant the additional inputs of infrastructure and labor. Hawkins (2017) also reported that other terminology for holistic management may include holistic resource management or the Savory (Savory, 1983) method. Allen et al. (2011) defined mob stocking as "a method of stocking at a high grazing pressure for a short time to remove forage rapidly as a management strategy." ...
Article
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Grazing management and stocking strategy decisions involve the manipulation of grazing intensity, grazing frequency, and timing of grazing to meet specific objectives for pasture sustainability and economic livestock production. Although there are numerous stocking systems used by stakeholders, these methods may be broadly categorized as either continuous or some form of rotational stocking. In approximately 30 published experiments comparing continuous vs. rotational stocking, there was no difference in liveweight gain per animal between stocking methods in 66% of studies. There was no difference in gain per ha between methods in 69% of studies, although for gain per ha the choice of fixed or variable stocking rate methodology affected the proportion (92% for fixed; 50% for variable). Despite these experimental results showing limited instances of difference between rotational and continuous stocking, rotational strategies (e.g., “mob stocking” or “regenerative grazing”) have received what appears to be unmerited acclaim for use for livestock production. Many proposed “mob stocking” or “regenerative grazing” systems are based on philosophies similar to high intensity-low frequency stocking, including provision for > 60 days of rest period from grazing. In addition, grazing management practitioners and stakeholders have voiced and proposed major positive benefits from rotational stocking, “mob stocking”, or “regenerative grazing” for soil health attributes, carbon sequestration, and ecosystem services, without experimental evidence. The perceptions and testimonials supporting undefined stocking systems and methods have potential to mislead practitioners and result in economic disservices. Thus, we suggest that scientists, Extension-industry professionals, and producers seek replicated experimental data as the basis for predicting outcomes of grazing decisions.
... Numerous studies aimed to assess the ecological impacts of high-density grazing systems versus conventional systems on rangeland status. Reviews of literature (Holechek et al., 2000;Teague et al., 2013;Briske et al., 2014;Nordborg, 2016;Hawkins, 2017;Gosnell et al., 2020;Hawkins et al., 2022) indicate that the evidence of high-density grazing systems providing the claimed ecological benefits is rather mixed, at best, especially when high-density grazing is compared with other forms of rotational grazing. While high-density grazing in semi-arid grasslands may increase organic matter in the upper part of the soil profile (Chaplot et al., 2016), it may also result in soil compaction, reduced soil aggregate stability and decreased soil moisture (Chamane et al., 2017;Roberts and Johnson, 2021). ...
... A switch from conventional to high-density grazing systems does require additional investments in farm infrastructure, livestock and more intensive forms of management (Teague et al., 2013). Evidence from the literature that high-density grazing systems lead to higher productivity and profitability per unit area is scarce and inconclusive (Hawkins, 2017;Venter et al., 2019;Derner et al., 2021;Hawkins et al., 2022) and studies on this topic struggle with the same methodological issues as studies on ecological impacts. ...
Article
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High-density grazing is a form of rangeland management aiming to strategically mimic the ways grasslands are utilized by grazers in natural situations. It aims to regenerate grasslands by improving soil and vegetation productivity and diversity. More recently, high-density grazing systems have been promoted as a key approach to mitigating climate change by increasing the amount of carbon sequestered in grassland soils. In this article, we describe the historical background of grazing and rangeland degradation in southern Africa, the principles of high-density grazing, and the problems it aims to address. We briefly discuss evidence of the potential benefits of high-density grazing, though we do not aim to provide an exhaustive review on this. We explore to what extent high-density grazing can be regarded as representative of grazing in natural ecosystems and whether the assumed link between nature and high-density grazing has been helpful in capitalizing on the potential merits of high-density grazing. While high-density grazing may represent a form of sustainable rangeland management, the main attractiveness to farmers likely relates to potential increases in livestock densities and associated productivity per unit area, as well as to potential management and social benefits. Learning from nature and inspiration by nature can play an important role in the development and communication of sustainable grazing management systems. However, it is questionable to what extent high-density grazing systems can be seen as more representative of natural ecosystems than other grazing management systems. The claimed ecological superiority of high-density grazing because of its association with nature has polarised and blurred the discussion on the potential merits of high-density grazing. Moreover, the supposed relationship between nature and high-density grazing may have led to an overselling of high-density grazing principles and an embracement of them by policy makers and development agencies without sufficient empirical basis.
... (2) Collect pre-program data on GAs. The evaluation team collected information on pre-429 program characteristics of each GA from interviews with TAs and AE staff, the 430 Namibian national census 37 , and the Namibian Atlas 38 . The latter has a geo-431 referenced database on climate, ecology, and livestock for the nation. ...
... Many research trials comparing rotational grazing to continuous grazing have failed to find a consistent and significant benefit to either forage yield or livestock production 36,37 . Trials were conducted on research stations where the experimental paddocks were small and research herds likewise small, sometimes only 3-4 head of cattle. ...
... Two limitations of previous rotational grazing studies are their limited spatial extent (small paddocks) and the use of fixed grazing schedules that ignored the human dimensions of adaptive decision making associated with multipaddock rotational grazing. Relationships between grazing systems and vegetation outcomes may operate differently in the context of adaptive management decision making at broad scales, where managers are often dealing with spatial and temporal variation in plant phenology, weather, plant community composition, and objectives ( Briske et al. 2011 ;Hawkins 2017 ;Hawkins et al. 2017 ;Teague and Barnes 2017 ). To address these limitations, we investigated tiller defoliation dynamics of western wheatgrass within the Collaborative Adaptive Rangeland Management experiment, located in the shortgrass steppe of eastern Colorado ( Wilmer et al. 2018 ;Fernández-Giménez et al. 2019 ;Augustine et al. 2020 ). ...
... Thus, there should be more potential for within-season regrazing (and more potential for tiller-scale benefits of rotation) in systems where two conditions are met: 1) forage quality is a stronger driver of foraging behavior than other factors like bite size, and 2) palatable plants are able to quickly regrow after defoliation. These conditions would be more common in mesic or fertile systems where overall biomass is higher and grazed plants have more resources available for regrowth after defoliation ( Maschinski and Whitham 1989 ;Heitschmidt et al. 1990 ;Hawkins 2017 ;Venter et al. 2020 ). However, several studies in mesic systems have failed to document strong effects of grazing system on levels of selectivity or regrazing rates at the plant scale ( Volesky 1994 ;Venter et al. 2019 ). ...
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Frequent, severe defoliation reduces grass production and can alter plant species composition in grasslands. Multipaddock rotational grazing has been proposed as a grazing strategy that may reduce the frequency and intensity of defoliation on palatable grass plants without altering stocking rates. Previous studies evaluated this hypothesis using small, homogeneous paddocks and nonadaptive rotation schedules and found small and inconsistent differences between continuous and rotational grazing systems. Using a stakeholder-driven collaborative adaptive management (CAM) framework, we conducted the first ranch-scale experimental investigation into tiller defoliation patterns in the context of adaptive multipaddock rotational grazing. We monitored tiller defoliation frequency and intensity in 10 paired 130-ha pastures assigned to either a collaborative adaptive multipaddock rotational grazing treatment (CARM, one livestock herd) or a season-long continuous grazing treatment (traditional rangeland management [TRM]; 10 separate herds) in shortgrass steppe. Consistent with previous studies, we observed that frequencies of grazing and regrazing on a palatable, cool-season grass (western wheatgrass, Pascopyrum smithii) were much more sensitive to stocking rate than grazing system. Under moderate stocking rates used in both CARM and TRM treatments, roughly two-thirds of western wheatgrass tillers remained ungrazed annually, regardless of grazing system. Thus, season-long rest is present in season-long continuous and rotational grazing systems. Frequencies of tiller regrazing were low (5−15%) and similar between CARM and TRM treatments. Although defoliation patterns were similar between treatments at the whole-ranch scale, CARM enhanced spatial and temporal heterogeneity in defoliation frequencies among individual pastures. Pastures grazed earlier in the season or for longer experienced more defoliation. Managers implementing adaptive, multipaddock rotational grazing could use this heightened and predictable variability to strategically manage impacts of grazing on western wheatgrass at the individual pasture scale. The CAM model enabled our team to identify and directly address key stakeholder hypotheses and resulted in coproduction of management-relevant research.
... Although livestock producers around the world use HRM and many are adamant supporters of the approach, experimental evidence from controlled range studies fails to support many of the ecological benefits HRM proponents claim to observe, such as increases in soil carbon and plant and animal production. [3][4][5][6][7] Yet, many ranchers remain steadfast and vocal advocates of HRM, pointing to their own experiences as sufficient evidence to promote HRM as an effective tool for sustainable rangeland management. 8,9 As a result, science and personal experience stand at an impasse. ...
... The actual grazing implications of the method (or the HPG elements), which are the primary focus of most rangeland science studies, need to be further evaluated in the context of the social and economic needs and drivers operating on ranches, and in the context of rancher decisionmaking. 6 Most of the ranchers emphasized the planning benefits of HRM over the grazing benefits, suggesting the value of the system is not in how the cattle are grazed but in how it changes the way ranchers make decisions about how to graze their cattle and manage the many other complexities of operating a ranch. Although these benefits are not exclusive to HRM and can likely be achieved through other systematic planning approaches, HRM provides a welldeveloped framework for managing the complexity inherent in a ranching enterprise and tools for adaptive decisionmaking. ...
Article
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On the Ground •Holistic Resource Management (HRM) is a ranch management strategy plagued by controversy; experimental evidence from ecological studies has consistently failed to support that HRM provides ecological benefits, yet many ranchers staunchly support the method. •Using a qualitative approach, we found that the HRM processes used on four case study ranches in eastern Colorado provided a systematic framework for key ranch stakeholders to improve long-term, adaptive approaches to managing ranches as complex socioecological systems. •Notably, the ranchers emphasized the planning benefits of HRM over the grazing benefits, suggesting the value of the system is not in how the cattle are grazed but in how it changes the way ranchers make decisions about how to graze their cattle and manage the many other complexities of operating a ranch. •Approaching HRM as a planning framework versus as a grazing strategy may be a key factor in the difference in claims between ranchers practicing HRM and researchers studying grazing systems.
... Incorporating periods of planned rest into grazing regimes, hereafter called strategic-rest grazing, is an alternative to continuous grazing management that is thought to reduce environmental degradation while maintaining or improving productivity (Hart, Clapp, & Test, 1993;Norton, 1998;Teague et al., 2008). Previous reviews have concluded that there are few benefits for animal production and landscape sustainability from strategic-rest grazing systems, yet significant knowledge gaps remain (Briske et al., 2008;Hawkins, 2017;Holechek, Gomes, Molinar, Galt, & Valdez, 2000;Nordborg, 2016;Teague, Provenza, Kreuter, Steffens, & Barnes, 2013). Climate type, the length of time land is rested relative to time grazed and differences in stocking rates between treatments compared have been shown to affect responses to grazing (Briske et al., 2008;Eldridge et al., 2016;Teague, Grant, & Wang, 2015). ...
... The large amount of residual heterogeneity in the meta-analyses indicate that these and other unexplained factors were likely influencing outcomes. Similar issues were encountered by Hawkins (2017). Unfortunately, much of this unexplained variation is challenging to overcome in the context of complex agro-ecological systems influenced by environmental, social and economic factors that are difficult to replicate or control for in field experiments (Briske et al., 2008;Heady, 1961;Provenza et al., 2003;Teague et al., 2013). ...
Article
Grazing can have considerable ecological impacts when managed inappropriately, however livestock production is a significant contributor to global food security and the removal of land from production is not always a viable option. Grazing management practices that incorporate periods of planned rest (i.e. strategic‐rest grazing) may be an alternative to grazing exclusion or continuous grazing that could achieve ecological and animal production outcomes simultaneously. We conducted a meta‐analysis of global literature to investigate how strategic‐rest grazing mediates ecological (i.e., plant richness and diversity), biophysical (plant biomass and ground cover) and production response variables (animal weight gain and animal production per hectare) compared to continuously grazed or ungrazed areas. Overall, total ground cover and animal production per hectare were significantly greater under strategic‐rest grazing than continuous grazing management, but biomass, plant richness, plant diversity and animal weight gain did not differ between grazing treatments. Increasing the length of rest relative to graze time under strategic‐rest grazing was associated with an increase in plant biomass, ground cover, animal weight gain and animal production per hectare when compared to continuous grazing. Synthesis and applications . Understanding both the ecological and animal production trade‐offs associated with different grazing management strategies is essential to make informed decisions about best‐management practices for the world's grazing lands. We show that incorporating periods of rest into grazing regimes improves ground cover and animal production per hectare and that these benefits are more pronounced with increases in the length of time land is rested for. This extended rest also improves biomass production and weight gain compared to continuous grazing systems. Based on these meta‐analyses, we recommend that future research considers the duration of rest compared to graze time in comparisons of grazing systems.
... The role of periodic, full season rests is not often adequately described in various meta-analyses and evaluations of grazing systems, probably because most management focuses on grazer movements within a single grazing season, rather than across years (Barnes, 1992;O'Reagain and Turner, 1992;Briske et al., 2008;Teague et al., 2013;Hawkins, 2017;McDonald et al., 2019). Evaluating the impacts of periodic full season rests on grassland ecosystem health and livestock performance logically requires a multiyear study, which might explain the lack of clear differentiation between the outcomes of experiments examining continuous and rotational grazing. ...
... Hoof action of livestock is suggested to break hard setting soil crusts, thus facilitating nutrient cycling, microbial activity, and carbon sequestration, but this has not been adequately tested and needs careful attention where biological crusts are dominant (Hawkins, 2017). This phenomenon also varies between land types and may be less relevant in Australia where there were no native hard-hoofed animals prior to colonisation (Garnett et al., 2017). ...
Article
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The livestock industry accounts for a considerable proportion of agricultural greenhouse gas emissions, and in response, the Australian red meat industry has committed to an aspirational target of net-zero emissions by 2030. Increasing soil carbon storage in grazing lands has been identified as one method to help achieve this, while also potentially improving production and provision of other ecosystem services. This review examined the effects of grazing management on soil carbon and factors that drive soil carbon sequestration in Australia. A systematic literature search and meta-analysis was used to compare effects of stocking intensity (stocking rate or utilisation) and stocking method (i.e, continuous, rotational or seasonal grazing systems) on soil organic carbon, pasture herbage mass, plant growth and ground cover. Impacts on below ground biomass, soil nitrogen and soil structure are also discussed. Overall, no significant impact of stocking intensity or method on soil carbon sequestration in Australia was found, although lower stocking intensity and incorporating periods of rest into grazing systems (rotational grazing) had positive effects on herbage mass and ground cover compared with higher stocking intensity or continuous grazing. Minimal impact of grazing management on pasture growth rate and below-ground biomass has been reported in Australia. However, these factors improved with grazing intensity or rotational grazing in some circumstances. While there is a lack of evidence in Australia that grazing management directly increases soil carbon, this meta-analysis indicated that grazing management practices have potential to benefit the drivers of soil carbon sequestration by increasing above and below-ground plant production, maintaining a higher residual biomass, and promoting productive perennial pasture species. Specific recommendations for future research and management are provided in the paper.
... In their meta-analysis conducted under a wide range of environmental conditions worldwide, Byrnes et al. (2018) found that rotational grazing could improve soil organic carbon and bulk density over continuous grazing strategies, which could have eventual benefits for pasture production. On the other hand, the meta-analyses conducted by Briske et al. (2008) and Hawkins (2017) reported no evidence that AMP grazing has an enhanced effect on vegetation characteristics compared to less rotational practices. Experimental limitations (e.g., spatial limitations, short-term nature, and inflexible grazing treatments) have prevented researchers from adequately accounting for the spatial heterogeneity of vegetation in AMP systems (Teague et al., 2013). ...
Article
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Adaptive Multi-Paddock (AMP) is a grazing system which combines intensive, rapid grazing livestock rotation with relatively short grazing periods and long recovery time after grazing. The study assesses, under Mediterranean silvopastoral systems, changes in pasture phenology and spatial variability after adopting the AMP under contrasting land cover (Wooded Grassland vs Grassland ) with a remote sensing approach based on the time-series analysis of Normalized Difference Vegetation Index (NDVI) from remote sensing through Landsat satellite. The study revealed an overall positive effect of rotational grazing on pasture phenology and NDVI spatial variability. The AMP adoption resulted in higher estimated values of NDVI at the beginning (under grassland land cover), the end, and the peak of the growing season, while no differences were observed in parameters estimating the length of the growing season. The spatial variability of NDVI was always lower under AMP than in continuously grazed areas, except in the early stages of the growing season under grassland land cover. The results suggested that in a relatively short period (4-5 years), the AMP grazing system can represent a strategy to improve forage availability and exploitation by grazing animals under low stocking rates in extensively managed Mediterranean silvopastoral systems.
... A 45-day grazing (that is, animals graze once in 45 days) frequency was considered for winter because subtropical grass growth is very low in this season (Cosgrove et al., 2003;Meat and Livestock Australia, 2021;Shelton, 2021). Also, a continuous stocking strategy was considered since some farms practice this method (Hawkins, 2017;Wang et al., 2016). In a continuous stocking strategy, grazing is carried out daily to return biomass to the residual biomass adopted. ...
Article
This study aimed to model pasture production for sub-tropical grass under different photovoltaic installations and assess the effects of different grazing methods on sub-tropical pasture productivity in Australia.
... Controversially, a study performed in Colombia under short duration grazing systems indicated higher pasture and animal productivity with further positive impacts on soil quality [41]. In another meta-analysis comparing the performance of holistic planned grazing versus seasonally continuous grazing at moderate stocking rates in different countries and ecosystems, no difference was found regarding plant and animal productivity [210], which can be a result of erroneous selection of grazing factors such as low stocking rates, long occupation periods and/or inadequate recovery period for the pasture. In the Piedmont region of Georgia, United States however, a continuous grazing system approach was more detrimental for soil health and increased runoff compared to strategic grazing [211]. ...
Article
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Grasslands and ecosystem services are under threat due to common practices adopted by modern livestock farming systems. Design theory has been an alternative to promote changes and develop more sustainable strategies that allow pastoral livestock production systems to evolve continually within grasslands by enhancing their health and enabling the continuous delivery of multiple ecosystem services. To create a design framework to design alternative and more sustainable pastoral livestock production systems, a better comprehension of grassland complexity and dynamism for a diagnostic assessment of its health is needed, from which the systems thinking theory could be an important approach. By using systems thinking theory, the key components of grasslands—soil, plant, ruminant—can be reviewed and better understood from a holistic perspective. The description of soil, plant and ruminant individually is already complex itself, so understanding these components, their interactions, their response to grazing management and herbivory and how they contribute to grassland health under different climatic and topographic conditions is paramount to designing more sustainable pastoral livestock production systems. Therefore, by taking a systems thinking approach, we aim to review the literature to better understand the role of soil, plant, and ruminant on grassland health to build a design framework to diagnose and enhance grassland health under pastoral livestock production systems.
... The studies showed that there was a small portion of rangelands has the capacity to sustain HPG. There is also attention to investigate how the holistic planned grazing (HPG) affects socio-ecological constitution of rangelands (Hawkins, 2017). Rochea et al. (2015) reported that Over 93% of all rotational grazer defendants in California characterized as using extensive intra-growing season rotation with moderate grazing period durations, livestock densities, and growing season rest periods. ...
... The kind of grazing that results from HM is typically called Holistic Planned Grazing: high-intensity and short-duration, and requires paddock subdivision, moveable water points and other significant changes to infrastructure and farming paradigm (Gosnell, Gill, and Voyer 2019). Savory's (2013) TED talk on HM inspired new debate in academe and the public sphere about whether 'it works' (Garnett et al. 2017;Hawkins 2017;Nordborg and Röös 2016), and whether what is really needed in the face of climate change is more livestock (Monbiot 2014, August 4, 2014. In recent decades, advocates of HM and similar approaches have largely bypassed public debate and the academic literature, instead working directly with farmers through institutes and training. ...
Article
First 50 downloads free at https://www.tandfonline.com/eprint/MP8AQ2REZHKZI4U8KU7J/full?target=10.1080/21683565.2022.2107597 ** Adaptive multi-paddock (AMP) grazing practices have been debated based on production, environmental and workload impacts, but farmer wellbeing is only beginning to be explored. A panel-based online survey of 200 Canadian beef producers was undertaken in early 2020 with a descriptive aim to explore the uptake, management, mindsets, and wellbeing implications associated with AMP grazing. AMP practices were more common than expected (29%) as well as distinct in grazing regime, featuring fast rotation, and long rests. AMP ranchers reported high physical wellbeing, as well as systems thinking, nontraditional values, a priority for enjoying life and tendency to use a wide range of modes to learn about grazing. Other dimensions of wellbeing, environmental motivations, and gender dimensions suggested by smaller-n studies were not associated with AMP grazing in this work. These insights are important as the federal government begins to promote AMP grazing and its variants as strategies to combat climate change. More nuanced understanding of adaptive grazing and its trajectory would be possible via consistent, longitudinal surveys with improved operationalization of well-being concepts, more detailed exploration of educational background , inclusion of religious beliefs, and elucidation of management characteristics beyond grazing regime variables.
... It has also been advocated that to obtain the greatest productivity benefit from RG, paddock rest periods need to be varied according to the season to account for changes in forage growth rate (Voisin, 1959), although many studies in our dataset applied the same grazing and rest periods across the whole grazing season. The increase in DM production with lengthened rest period, and the implication from Fig. 3 that livestock growth rates can be maintained as stocking density increases if rest periods are sufficiently long, appears to suggest that RG can support higher stocking densities than continuous grazing, as has been found in Australia (Badgery and Michalk, 2017) although disputed in a rangeland context (Hacker, 1993;Briske et al., 2008;Hawkins, 2017). In our analysis, however, rest period and stocking density are non-independent. ...
Article
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Reducing greenhouse gas emissions associated with ruminant livestock production is important for climate change mitigation. Regenerative Agriculture (RA) practices are increasingly promoted to improve forage production and livestock performance in temperate livestock systems. These practices include i) rotational grazing (RG) of livestock around multiple subunits of pasture to achieve ungrazed periods of ‘rest’, and ii) herbal leys (HL), where perennial forbs such as chicory, lucerne and trefoils are included as components in multi-species swards. While there are plausible mechanisms for adoption of these practices to improve agricultural productivity, quantitative syntheses of their impacts are required. Here, we conduct a systematic review and meta-analysis of the effects of RG and HL practices on herbage dry matter (DM) production, animal daily liveweight gain (DLWG), and sheep wool growth in temperate oceanic regions. We use quantitative predictors in our Bayesian hierarchical models to investigate the role of rest period and stocking density in RG systems, and specific plant traits and sward diversity in HL. We found that herbage DM increased by 0.31 t.ha⁻¹ over a growing season as the proportion of rest in an RG grazing system increased from 0 to 1. Stocking density significantly moderated the effect of rest period on sheep and cattle DLWG; at higher stocking densities, longer rest periods were required to maintain livestock growth rates. In HL studies, herbage DM yielded 1.63 t.ha⁻¹ more per metre of increased sward root depth and a sward entirely comprised of legumes yielded 2.20 t.ha⁻¹ more than when no legumes were present. Sheep DLWG increased by 3.50 g.day⁻¹ per unit increase in leaf nitrogen concentration (mg.g⁻¹), but we could not determine an effect of leaf condensed tannin content on animal performance. Although there remain differences between the RG and HL study treatments meta-analysed here and RA in practice, our results provide empirical support for some of the mechanisms attributed to increased pasture and livestock productivity following adoption of selected RA grazing practices.
... Studies more commonly report on mob grazing as a means of 1) controlling undesirable shrubs ( Bailey and Brown 2011 ;Mesléard et al. 2017 ) and exotic species ( James et al. 2017 ), 2) manipulating proportions of C 3 and C 4 plants in a management unit ( Hickman et al. 2004 ), and 3) improving distribution of grazing and evenness of utilization of vegetation cover ( Barnes et al. 2008 ;Norton et al. 2013 ;Reed et al. 2019 ). Animal performance in a mob grazing system is commonly reported to be less than on less intensively managed pastures (simple rotationally and continuously stocked pastures) ( Hawkins 2017 ;Tracy and Bauer 2019 ;Augustine et al. 2020 ), likely because of extremely high grazing pressure and consumption of lower-quality forage ( Tracy and Bauer 2019 ). ...
Article
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Management-intensive grazing, which is proposed to increase forage and animal productivity and maintain soil integrity and biodiversity, is seen as an alternative to meet 21st century agricultural and environmental challenges. The purpose of this study was to test the hypothesis that high levels of trampling of standing vegetation associated with mob grazing (a.k.a., ultrahigh stocking density) leads to increased plant diversity and productivity. A long-term experiment was established on a subirrigated meadow in the Nebraska Sandhills as a complete block design comparing three grazing treatments applied annually during the growing season for 8 consecutive yr (2010−2017): 120-pasture rotation with one grazing cycle (mob; 225 000 kg live weight ha⁻¹), four-pasture rotation with one grazing cycle (4PR1; 7 000 kg live weight ha⁻¹), and four-pasture rotation with two grazing cycles (4PR2; 5 000 kg live weight ha⁻¹). All treatments were set at a moderate stocking rate (7.4 animal unit months ha⁻¹) using yearling steers. Percentage trampling, plant production, species composition, and steer weight gain were estimated annually. We applied linear mixed-effect models to account for year and treatment effect on the response variables. Percentage trampling on mob pastures ranged from 40% to 55% over the 8 yr of the study, nearly double that of the 4PR1 and 4PR2 pastures. We observed that mob grazing had no overall effect on plant species composition, aboveground production, and root growth relative to low stocking densities. Average daily gain of steers in the mob pastures was less than gain of steers in 4PR2 pastures in all years, with intermediate weight gains for the 4PR1 steers. Overall, stocking density did not appear to be a driver of plant composition and productivity in rotationally grazed pastures on subirrigated meadows in the Nebraska Sandhills.
... Grazing practices that incorporate periods of planned rest are commonly promoted to avoid environmental degradation and improve productivity (Norton 1998a;Teague et al. 2008) but considerable debate exists around the benefits, or otherwise, of these grazing management systems (Briske et al. 2008;Teague et al. 2013). Previous reviews have generally concluded that there is little difference in outcomes for animal production (i.e., weight gain, production per unit area, reproductive success) or rangeland sustainability (i.e., maintenance of biomass or ground cover) between contrasting management systems (Gammon 1978;O'Reagain and Turner 1992;Holechek et al. 2000;Briske et al. 2008;Hawkins et al. 2017;di Virgilio et al. 2019). Yet, recent meta analyses indicate that alternative grazing systems that incorporate periods of rest, compared with continuously grazed or ungrazed areas, have the potential to achieve multiple objectives (e.g. ...
Conference Paper
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With increasing pressure on grazing lands throughout the world, there is a growing need to balance sustainable management of livestock to meet food production and environmental impacts. Grazing management practices that incorporate periods of planned rest between grazing events (RG) may achieve both ecological and production goals simultaneously. We conducted a systematic review of global literature that compared ecological and production outcomes of RG systems with either continuously grazed (CG) or ungrazed (UG) areas. In addition, we evaluated the extent to which ecological and livestock production outcomes have been assessed simultaneously in these studies and identified future research needs. A large proportion of the literature reported no difference (neutral response) between the different management systems. However, where differences did occur, the response of biodiversity, land condition and livestock production metrics was more often positive under RG than CG. When RG was compared to UG areas, differences were predominantly positive for plant biodiversity metrics, but negative for invertebrate biodiversity, ground cover and plant biomass. Only a small proportion of studies considered the effect of RG on both ecological and production outcomes simultaneously. An understanding of both ecological and production trade-offs associated with different grazing management strategies is essential to make informed decisions about best-management practices for joint production and ecological outcomes across the world's grazing lands.
... Rangelands are the most extensive land cover type on earth and provide numerous ecosystem services, such as biodiversity, water, carbon sequestration, food, fiber, fuel, and cultural values ( Briske,Figure 1. Simplified diagram of the beef cattle weight gain process in APEX. ( Briske et al. 2008( Briske et al. , 2011Hawkins 2017 ;Harmel et al. 2021 ). For example, Teague et al. (2013) concluded that several factors influence the potential benefits of rotational grazing, including 1) providing for adequate plant recovery, 2) modifying livestock distribution and grazing intensity, and 3) regulating livestock nutrition and feeding behavior. ...
Article
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Rotational grazing studies have produced mixed results related to animal performance (weight gain), which has contributed to producer uncertainty regarding grazing management decisions. To enhance decision-support for producers, we improved algorithms in the Agricultural Policy/Environmental eXtender (APEX) model to better represent cattle weight gain in real-world rangeland conditions under two grazing management strategies. Simulated weight gain and related forage effects were evaluated with experimental data from 2014 to 2018 under two grazing strategies. The traditional rangeland management strategy used continuous season-long grazing stocked at a moderate level. The collaborative adaptive rangeland management strategy employed grazing with one large herd rotated using a sequence developed by a stakeholder group with movement between pastures driven by predetermined decision triggers. For each grazing strategy, yearling steers grazed from mid-May to October on ten 130-ha pastures. With the APEX modifications, daily weight gain was adequately simulated for both continuous (traditional rangeland management) grazing and management intensive rotational (collaborative adaptive rangeland management) grazing. Dry matter intake, total digestible nutrients, and temporal distribution of dry matter intake were the primary influencers of cattle performance (weight gain). Once shown to be accurate, we used APEX to evaluate several management alternatives (i.e., stocking rate, rotation interval, and rotation decision criteria) to showcase its decision support capabilities. These important enhancements increase the utility of APEX in semiarid environments, such as the western Great Plains, in providing science-based rangeland decision support to ranchers, agency land managers, and policy makers.
... Claims about the ubiquitous superiority of ReGM are controversial, divisive, and strongly contested (see Briske et al., 2013;Sherren and Kent, 2019;Gosnell et al., 2020), spurring numerous studies, reviews (Skovlin, 1987;Holechek et al., 2000;Briske et al., 2008;Nordborg, 2016;Hawkins et al., 2022) and a meta-analysis (Hawkins, 2017). These studies and syntheses have revealed varied ecosystem and agronomic responses to ReGM with little compelling empirical evidence that ReGM will improve grass and animal production and vegetation condition wherever it is applied. ...
Article
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Regenerative grazing management (ReGM) seeks to mimic natural grazing dynamics to restore degraded soils and the ecological processes underpinning sustainable livestock production while enhancing biodiversity. Regenerative grazing, including holistic planned grazing and related methods, is an adaptive, rotational stocking approach in which dense livestock herds are rotated rapidly through multiple paddocks in short bouts of grazing to defoliate plants evenly and infrequently, interspersed with long recovery periods to boost regrowth. The concentrated "hoof action" of herds in ReGM is regarded vital for regenerating soils and ecosystem services. Evidence (from 58 studies) that ReGM benefits biodiversity is reviewed. Soils enriched by ReGM have increased microbial bioactivity, higher fungal:bacteria biomass, greater functional diversity, and richer microarthropods and macrofauna communities. Vegetation responds inconsistently, with increased, neutral, or decreased total plant diversity, richness of forage grasses and invasive species under ReGM: grasses tend to be favored but shrubs and forbs can be depleted by the mechanical action of hooves. Trampling also reduces numerous arthropods by altering vegetation structure, but creates favorable habitat and food for a few taxa, such as dung beetles. Similarly, grazing-induced structural changes benefit some birds (for foraging, nest sites) while heavy stocking during winter and droughts reduces food for seedeaters and songbirds. With herding and no fences, wildlife (herbivores and predators) thrives on nutritious regrowth while having access to large undisturbed areas. It is concluded that ReGM does not universally promote biodiversity but can be adapted to provide greater landscape habitat heterogeneity suitable to a wider range of biota.
... Claims about the ubiquitous superiority of ReGM are controversial, divisive, and strongly contested (see Briske et al., 2013;Sherren and Kent, 2019;Gosnell et al., 2020), spurring numerous studies, reviews (Skovlin, 1987;Holechek et al., 2000;Briske et al., 2008;Nordborg, 2016;Hawkins et al., 2022) and a meta-analysis (Hawkins, 2017). These studies and syntheses have revealed varied ecosystem and agronomic responses to ReGM with little compelling empirical evidence that ReGM will improve grass and animal production and vegetation condition wherever it is applied. ...
Preprint
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Regenerative grazing management (ReGM) seeks to mimic natural grazing dynamics to restore degraded soils and the ecological processes underpinning sustainable livestock production while enhancing biodiversity. Regenerative grazing, including holistic planned grazing and related methods, is an adaptive, rotational stocking approach in which dense livestock herds are rotated rapidly through multiple paddocks in short bouts of grazing to defoliate plants evenly and infrequently, interspersed with long recovery periods to boost regrowth. The concentrated 'hoof action' of herds in ReGM is regarded vital for regenerating soils and ecosystem services. Evidence (from 58 studies) that ReGM benefits biodiversity is reviewed. Soils enriched by ReGM have increased microbial bioactivity, higher fungal:bacteria biomass, greater functional diversity, and richer microarthropods and macrofauna communities. Vegetation responds inconsistently, with increased, neutral, or decreased total plant diversity, richness of forage grasses and invasive species under ReGM: grasses tend to be favoured but shrubs and forbs can be depleted by the mechanical action of hooves. Trampling also reduces numerous arthropods by altering vegetation structure, but creates favourable habitat and food for a few taxa, such as dung beetles. Similarly, grazing-induced structural changes benefit some birds (for foraging, nest sites) while heavy stocking during winter and droughts reduces food for seedeaters and songbirds. With herding and no fences, wildlife (herbivores and predators) thrives on nutritious regrowth while having access to large undisturbed areas. It is concluded that ReGM does not universally promote biodiversity but can be adapted to provide greater landscape habitat heterogeneity suitable to a wider range of biota. https://www.frontiersin.org/articles/10.3389/fevo.2021.816374/full
... Natural reserved forests are biodiversity-rich habitats on the globe because they host diversified flora and fauna species ( John et al., 2020 ;Kutnar et al., 2019 ;Lacerda and Kellermann, 2019 ;Chen and Tang, 2016 ;Hawkins, 2017 ). Forests and their trees support human and animal lives by the provision of various products and services ( Beltrán-Rodríguez et al., 2021 ;Ghanbari et al., 2021 ;Mohammed et al., 2021 ). ...
Article
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Forests and forest trees have continuously been supporting human beings through the provision of food and food-associated materials, fodder and foraging sites for their livestock, and medicinal materials, as well as multiple ecological services. However, unbalanced utilization of these resources and the biotic and abiotic disturbances interrupt their sustainability and ecological functions. We studied the tree population structure, diversity, and regeneration status of tree species in the Abu Gadaf Natural Reserved Forest in 46 sample plots of 20 m x 50 m (1000 m²) distributed systematically throughout the reserve over a year. The study findings showed that highland sites have higher tree species richness (47 species) compared to lowland sites (31 species) and the highest contributors are Combretaceae (21.3%) and Fabaceae (19.2%) families. Moreover, seedlings in highland sites are twice that of lowlands, with a significant difference between the two sites (F1,46 = 138.4, p < 0.001). The same trend has been observed for saplings and adult trees (F1,46 = 143.2, p < 0.01; F1,46 = 126.7, p < 0.01, respectively). Likewise, all dendrometric parameters and diversity indices demonstrated significant differences between the sites across the reserve with lower values in the lowland sites and vigorous regeneration in the highland sites (T = 33.7, P < 0.001; T = 22.3, P = 0.001; T = 27.9, P = 0.042, respectively). The study concludes that over browsing by livestock and intensive illegal tree logging in the lowland sites have severely affected the tree population composition, which might consequently disturb the regeneration process and seedlings recruitment. A conservation action plan is urgently needed to protect vulnerable species, especially those with low importance value index.
... Rangelands are the most extensive land cover type on earth and provide numerous ecosystem services, such as biodiversity, water, carbon sequestration, food, fiber, fuel, and cultural values ( Briske,Figure 1. Simplified diagram of the beef cattle weight gain process in APEX. ( Briske et al. 2008( Briske et al. , 2011Hawkins 2017 ;Harmel et al. 2021 ). For example, Teague et al. (2013) concluded that several factors influence the potential benefits of rotational grazing, including 1) providing for adequate plant recovery, 2) modifying livestock distribution and grazing intensity, and 3) regulating livestock nutrition and feeding behavior. ...
Article
CONTEXT Simulation tools are increasingly used to inform grazing management decisions by assessing livestock performance, as well as environmental and economic impacts. Ability to represent the grazing of multiple pastures (i.e., paddocks) that differ in soil, hydrology, vegetation, and management is critical for reliable grazing management decision support. OBJECTIVE The main objectives of this study were to: 1) modify APEX (Agricultural Policy/Environmental eXtender) for sub-daily grazing, cow-calf weight gain, and supplemental hay, and 2) evaluate the APEX modifications in terms of simulating biomass, calf weight gain, economic impacts of alternative cow-calf grazing management strategies. METHODS APEX was modified to enhance its ability to simulate alternative grazing management strategies by including sub-daily grazing among multiple paddocks, supplemental hay estimation, and optional simulation of cow-calf weight gain based either on energy or total digestible nutrients (TDN). Simulation results were evaluated against a 5-year experimental data set from Central Texas comparing multi-paddock rotational grazing and conventional continuous grazing. RESULTS AND CONCLUSION The modified APEX model adequately simulated the responses of vegetation biomass (coefficient of determination, R² = 0.60–0.70), hay consumption (R² = 0.94–0.95), calf weaning weight (R² = 0.52–0.65), costs (R² = 0.98), and profits (R² = 0.89) to the two grazing treatments across years. Simulations with the energy-based weight gain algorithm showed more pronounced effects on above-ground biomass, whereas the TDN-based algorithm had a more pronounced weight gain response to forage intake and hay quality. No significant differences (p > 0.05) in biomass and calf weaning weight were observed between treatments across the years for measured data and for energy-based APEX simulation; however, the TDN-based algorithm simulated lower calf weaning weight in multi-paddock rotational grazing than in continuous grazing. Measured and simulated data also showed similar profits between the two grazing treatments, but total cost and gross return per ha were greater for continuous grazing. SIGNIFICANCE The model enhancements for sub-daily grazing, cow-calf weight gain, and supplemental hay improved the potential utility of APEX for assessing environmental and economic impacts of alternative grazing strategies at ranch scale.
... Similarly, in the western rangelands of North America, rest-rotational, deferred rotational, seasonal suitability, best pasture, short duration, season-long, and continuous grazing or foraging systems are practised (Frost and Mosely, 2020). Among these systems in extensive environments, evidence exists that rotational or cell grazing is no more productive and is less profitable than set stocking for beef production (Briske et al., 2008;Hall et al., 2014Hall et al., , 2016Hawkins, 2017). ...
Article
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Beef is a high-quality source of protein that also can provide highly desirable eating experiences, and demand is increasing globally. Sustainability of beef industries requires high on-farm efficiency and productivity, and efficient value-chains that reward achievement of target-market specifications. These factors also contribute to reduced environmental and animal welfare impacts necessary for provenance and social licence to operate. This review provides an overview of beef industries, beef production, and beef production systems globally, including more productive and efficient industries, systems and practices. Extensive beef production systems typically include pasture-based cow-calf and stocker-backgrounding or grow-out systems, and pasture or feedlot finishing. Cattle in pasture-based systems are subject to high levels of environmental variation to which specific genotypes are better suited. Strategic nutritional supplementation can be provided within these systems to overcome deficiencies in the amount and quality of pasture- or forage-based feed for the breeding herd and for younger offspring prior to a finishing period. More intensive systems can maintain more control over nutrition and the environment and are more typically used for beef and veal from dairy breeds, crosses between beef and dairy breeds, and during finishing of beef cattle to assure product quality and specifications. Cull cows and heifers from beef seedstock and cow-calf operations and dairy enterprises that are mostly sent directly to abattoirs are also important in beef production. Beef production systems that use beef breeds should target appropriate genotypes and high productivity relative to maintenance for the breeding herd and for growing and finishing cattle. This maximizes income and limits input costs particularly feed costs which may be 60% or more of production costs. Digital and other technologies that enable rapid capture and use of environmental and cattle performance data, even within extensive systems, should enhance beef industry productivity, efficiency, animal welfare and sustainability.
... Among other factors, climate heterogeneity could affect the relative benefits of RG vs CG. For example, Hawkins (2017) found that most studies in areas with less than 400 mm precipitation showed negative or no significant RG benefits on plant basal cover and they concluded that RG is more suitable in areas with moderate or high precipitation. Given that the average annual precipitation in our study area is 626 mm with only 4.23% of the respondents having less than 400 mm rainfall, most of our survey respondents are located in moderate precipitation areas. ...
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Experimental findings on rotational grazing (RG) trials have generally differed from producer observations of RG outcomes on commercial scale ranches. Factors such as small plot size, short duration trials and relatively rigid grazing management that lacks responsiveness to the dynamic and complex social-ecological systems in grazing trials could all contribute to this disparity in outcomes. These differences call for a better understanding of producer perceptions of RG benefits. To fill this knowledge gap, we surveyed 4500 producers from the Northern and Southern Great Plains of the USA. Among the 875 respondents, 40.5% reported that they used continuous grazing (CG), 52.7% implemented RG management in an extensive manner, while 6.8% adopted management intensive grazing. Compared with CG users, adopters of RG in its extensive and intensive form reported an average annual increase of grazing season by 7.6 and 39.3 days, respectively. When controlling for producer demographics, ranch management goals and other rancher characteristics, we found soil and climate heterogeneity significantly affected the perceived relative benefits of RG vs CG strategies. Therefore, instead of focusing on whether RG outperforms CG per se , future research could focus on comparison of RG benefits under different management intensity levels and identifying soil and climate conditions where RG benefits are more noticeable.
... Interpreted at the time as irrational conservatism, pastoral reluctance to adopt rotational grazing makes sense in terms of the most systematic metanalysis yet conducted of the performance of these systems: "[S]ubjected to as rigorous a testing regime as any hypothesis in the rangeland profession, " rotational grazing systems have been found to "convey few, if any, consistent benefits" and it is likely that ". . . a continuation of costly grazing experiments adhering to conventional research protocols will yield little additional information" (Briske et al., 2008, p. 11; see also Heady, 1961;O'Reagain and Turner, 1992;Holechek et al., 2001;Bailey and Brown, 2011;Hawkins, 2017). Despite the decades of negative or mixed results in the works cited above, the debate about the efficacy of rotational systems in semi-arid rangelands grinds on without resolution (Teague et al., 2013;Briske et al., 2014). ...
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This essay examines three central components of extensive livestock production—herd composition, grazing/pasture management, and rangeland tenure. In all of these areas, fenced, and open-range forms of migratory pastoralism face a number of shared problems. Set aside the presumption that either one of these systems is technically or institutionally more advanced than the other, and it turns out that each has lessons for the other. 1. For a variety of reasons, including climate change, we can look forward to a future world with less grass, which presents a challenge for livestock producers reliant on grass feeding livestock. With little delay and minimal scientific support, East African pastoralists are already adjusting to a new woody world by diversifying the species composition of their herds to include more browsers—camels and goats. There is a potential lesson here for commercial ranchers who have traded the stability of mixed herds for the profitability of keeping sheep or cattle alone. 2. Migratory rangeland systems distribute livestock very differently than fenced, rotational systems of livestock, and pasture management. Whereas, migratory herds exploit environmental heterogeneity, fenced ranching attempts to suppress it. Emerging archaeological evidence is demonstrating that pastoralists have amplified rangeland heterogeneity for millennia; ecological research shows that this heterogeneity sustains both plant and wildlife biodiversity at the landscape scale; and new approaches to ranch management are appropriating aspects of migratory herding for use on fenced ranches. A rapprochement between the environmental sciences, ranching, and open-range migratory pastoralism has occurred and merits wider policy recognition. 3. In contemporary Africa, indigenous tenure regimes that sustain open rangelands are eroding under pressure from market penetration and state encapsulation. At the same time in the American West, there are emerging novel land tenure instruments that replicate some of the most important functional characteristics of tenure arrangements in pastoral Africa. After many false starts, it appears that some aspects of American ranching do provide an appropriate model for the preservation of the open-range migratory systems that they were once supposed to supplant. “Development” policy needs to reflect upon this inversion of roles and its implications for accommodating diversity.
... Rangeland productivity depends on the grazing management of biotic (browsers, large and small stock) and abiotic (climate and lithology) components of the Drakensberg farming system (Hawkins 2017). Rangeland management in southern Africa comprises rotational grazing, zero grazing, or a combination of both, monitoring stocking rate, camp size, and recovery periods. ...
... Rangeland productivity depends on the grazing management of biotic (browsers, large and small stock) and abiotic (climate and lithology) components of the Drakensberg farming system (Hawkins 2017). Rangeland management in southern Africa comprises rotational grazing, zero grazing, or a combination of both, monitoring stocking rate, camp size, and recovery periods. ...
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Achieving sustainable food security is a critical goal for smallholder farmers in mountainous regions around the world. In the 40,000 km2 Maloti–Drakensberg mountains (South Africa and Lesotho), one of the important mountain ranges of southern Africa, farmers are directly dependent on natural resources. Natural resource management is currently unsustainable, driving landscape degradation and entrenching poverty cycles. Through a comprehensive literature review, we explore the current status of knowledge, opportunities, and agriculture-dependent natural resource sustainability in the Maloti–Drakensberg, and outline the priorities for future research in mountain agriculture in southern Africa. The Maloti–Drakensberg has diverse land tenure systems and climatic heterogeneity that together determine farming practices. Agropastoralism is the predominant agricultural practice, occupying 79% of the land, because of the natural grass-dominated vegetation. Despite decades of concern, the sustainable management of communal rangeland remains elusive. Arable cropping is practiced on 12% of the land at subsistence levels, while game farming contributes a small amount to local revenues. A multipronged research approach is needed to understand the complex social–ecological issues around soil degradation and sustainable utilization of the limited agricultural natural resources base. Innovative and adaptive strategies that take into account local and indigenous knowledge, mitigate soil degradation, and enhance water and rangeland conservation are needed to promote sustainable food production in the Maloti–Drakensberg.
... 46 Alan Savory and other proponents and practitioners have claimed astonishing results in terms of reversing desertification and revegetating deteriorated rangelands as pictured above. Scientists have mostly failed to reproduce and therefore validate these results, a meta-analysis could find no difference between Holistically Planned Grazing and rotational grazing in plant biomass and weight gained by livestock(Hawkins 2017). However, most research on the topic has been criticised for their small scale, non-adaptiveness and short period because they have been "designed and conducted in46 Album with various photographs: http://www.holisticresults.com.au/your-resources/photo-albums ...
Thesis
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Humanity is confronted with a number of pressing and interrelated unsustainability crises including the stark reliance on dwindling finite resources, accelerating climate change, alarming rates of biodiversity loss, and degradation of natural habitats. Industrial agriculture as a specific regime of input intensive, mechanized, large-scale, and uniform food production is one main driver and therefore itself unsustainable. The public, policymakers, and farmers themselves increasingly worry about the decline in soil fertility, loss of topsoil and farming systems not resilient enough at the sight of a warming climate, more erratic rainfall, and predicted increase in drought events. Regenerative Agriculture is one recent contribution to the discourse on a more sustainable agriculture. It started to emerge as a distinct concept a few years ago and puts a strong focus on building soil organic matter in the context of carbon sequestration and climate change mitigation. Especially the USA have seen a surge in interest in Regenerative Agriculture from farmers, NGOs, and businesses. While articles and videos on the topic proliferate it has gained limited attention from scientists and no inquiry in the concept itself has been conducted. This thesis explores the existing scientific and grey literature on the topic to provide an overview of Regenerative Agriculture’s genesis since its first emergence in the 1980s, contemporary understandings regarding definitions, principles and practices, and contextualizes Regenerative Agriculture with other concepts of alternative agriculture including organic farming, climate-smart agriculture, and Conservation Agriculture. The extensive literature review and qualitative content analysis reveal that Regenerative Agriculture is a currently highly dynamic, contested, and entails a large number of at times complementary, at times contradictory understandings. To be a meaningful contribution to the quest for sustainability the more radical contributions to this evolving concept like the large-scale transition to perennial-centred farming systems need to be accentuated without forfeiting the momentum of this emerging movement. This thesis humbly contributes to a scientific discourse on Regenerative Agriculture that is both benevolent and critical which is deemed necessary to develop realistic answers to urgent crises.
... Although grazing systems for freeranging livestock have been an important topic of study ( Briske et al. 20 08 ; Laca 20 09 ; Teague et al. 2013 ), more specific information is needed on how individual grazing management practices, including the length of grazing periods during the growing season as affected by grazing system, impact rangeland sustainability. Continuous grazing is associated with livestock use through much or all of the growing season, with infrequent movement of animals between pastures ( Holechek et al. 2004 ;Teague et al. 2013 ;Hawkins 2017 ). This practice generally requires less infrastructure than rotational systems but can expose vegetation to https://doi.org/10.1016/j.rama.2020.08.007 1550-7424/© 2020 The Society for Range Management. ...
Article
Contemporary methods of rangeland health (RH) assessment evaluate indicators designed to assess land use impacts on ecosystem function. These methods have not been tested relative to variation in specific grazing practices, including grazing period length and stocking rates during the growing season. We report on RH outcomes for three habitat types (native grassland, tame pasture, and forested pasture) across 97 pastures on 28 beef cattle ranches in Alberta, Canada. Pastures were distributed along a climatic gradient encompassing the grassland, parkland/foothill, and boreal regions. Surveys of ranchers were used to quantify typical grazing period length (1 May–31 October) and, if applicable, rotation length, along with corresponding stocking rates for each pasture over the previous 5 yr. Pastures were assessed for RH using indicators of vegetation composition and structure, litter abundance, soil stability, weed presence, and within tame pastures, woody plant encroachment. An Akaike Information Criterion analysis compared the influence of aridity, grazing period length, and stocking rate on total range health scores (RHS) and ordination used to identify associations between indicator scores and grazing metrics. Total RHS varied among habitat types, being greater in forests than native and tame grasslands (P < 0.05), and declined with increasing forage utilization, particularly in forests. Within tame pastures, total RHS varied primarily in response to regional climate, with RHS decreasing as moisture deficits increased and declining with longer grazing periods during summer. Native grasslands also decreased in RHS in response to longer grazing periods, with stocking rates having little impact on RHS. Select RH indicators were associated with improved health in native grasslands grazed for shorter periods including low weed abundance and greater litter. Further studies are recommended to understand how, over and above climatic influences, variation in grazing practices alter the health of northern temperate grasslands.
... As scientific confidence in rotational grazing systems has declined (Heady, 1961;O'Reagain and Turner, 1992;Holechek et al., 2001), there has in recent years been a steady advance in the understanding of the ecological processes that underpin domesticated and wild animal migrations. Contrary to the disappointing performance of fenced rotational gazing (Briske et al., 2008;Bailey and Brown, 2011;Hawkins, 2017;Briske et al., 2014), migration sustains -in the air, in and under water, on land, from waterfowl, to herring and wildebeest -some of the greatest concentrations of animal biomass on earth (Milner-Gulland et al., 2011). Pastoral migrations and natural systems of wild animal migration have existed for millennia. ...
Article
At their furthest extent, the livestock migrations examined in this paper traverse a distance of 400 km or more along a north-south transect, crossing up to half a dozen distinct ecological zones and, upon occasion, the international border between Sudan and South Sudan. Official Sudanese recognition of the value of migratory livestock production has led in recent years to policy and legal changes that support pastoral mobility, but there remains a gap in the scientific evidence that can be called upon to inform this emerging awareness. This paper uses remotely sensed livestock tracking data to document pastoral behaviour in relation to some of the biophysical factors that are important for livestock survival and production. This research supports several policyrelevant conclusions: 1. In East Darfur, long-distance migratory livestock production is remarkably resilient to rainfall fluctuations, including drought and flooding, because movement cycles are already designed to accommodate this kind of variability. 2. Mobile livestock producers are exposed to human-generated disruption and increasing pressures on their mobility from expanding farms, localized conflict and insecurity, and a new international border. 3. Pastoralists need sympathetic governance to mediate their interactions with other forms of land use, which is unlikely to happen unless authorities appreciate the technical sophistication and economic advantages of migratory systems. 4. Migratory production in East Darfur uses locally available resources which leaves livestock owners and government free to expend cash reserves on other kinds of inputs, investments or activities.
... As scientific confidence in rotational grazing systems has declined (Heady, 1961;O'Reagain and Turner, 1992;Holechek et al., 2001), there has in recent years been a steady advance in the understanding of the ecological processes that underpin domesticated and wild animal migrations. Contrary to the disappointing performance of fenced rotational gazing (Briske et al., 2008;Bailey and Brown, 2011;Hawkins, 2017;Briske et al., 2014), migration sustains -in the air, in and under water, on land, from waterfowl, to herring and wildebeest -some of the greatest concentrations of animal biomass on earth (Milner-Gulland et al., 2011). Pastoral migrations and natural systems of wild animal migration have existed for millennia. ...
Article
At their furthest extent, the livestock migrations examined in this paper traverse a distance of 400 km or more along a north-south transect, crossing up to half a dozen distinct ecological zones and, upon occasion, the international border between Sudan and South Sudan. Official Sudanese recognition of the value of migratory livestock production has led in recent years to policy and legal changes that support pastoral mobility, but there remains a gap in the scientific evidence that can be called upon to inform this emerging awareness. This paper uses remotely sensed livestock tracking data to document pastoral behaviour in relation to some of the biophysical factors that are important for livestock survival and production. This research supports several policy-relevant conclusions: 1. In East Darfur, long-distance migratory livestock production is remarkably resilient to rainfall fluctuations, including drought and flooding, because movement cycles are already designed to accommodate this kind of variability. 2. Mobile livestock producers are exposed to human-generated disruption and increasing pressures on their mobility from expanding farms, localized conflict and insecurity, and a new international border. 3. Pastoralists need sympathetic governance to mediate their interactions with other forms of land use, which is unlikely to happen unless authorities appreciate the technical sophistication and economic advantages of migratory systems. 4. Migratory production in East Darfur uses locally available resources which leaves livestock owners and government free to expend cash reserves on other kinds of inputs, investments or activities.
... Area ( (HDSD, 1200 cows per ha for only 3 days per year) followed by complete exclosure for the remainng 362 days each year (Chaplot et al., 2016). On the basis of a global assessment of holistic planned grazing, however, Hawkins (2017) concluded that only rangelands with higher precipitation have the resources to support MP grazing at a high stocking rate. ...
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Per capita intake of animal protein is expected to increase globally through 2050, and the rate of increase will be more in developing or emerging economies than in developed countries. Global meat consumption between 1980 and 2050 is projected to increase from 133 million to 452 million tons, and 86% (279 million tons) of the increase will occur in developing countries. Animal-based agricultural systems occupy 45% of the global land area and contribute a large proportion of agricultural emissions. In addition to being a major source of nitrous oxide (N2O), methane (CH4), and other greenhouse gases (GHGs), livestock also use 8% of the global water withdrawal. The animal sector is dominated by resource-poor and small landholders of developing countries. Adverse effects of livestock on the environment are caused by the way animal husbandry is practiced, in no small part because animals are not integrated with other agricultural and forestry-based practices. Thus, improving and sustaining the livestock sector is critical to advancing the Sustainable Development Goals (SDGs) of the United Nations, especially SDG #1 (No Poverty), SDG #2 (Zero Hunger), SDG #6 (Clean Water and Sanitation), and SDG #13 (Climate Action). Separating raising of livestock from cultivating seasonal crops and perennial trees has decoupled the biogeochemical/biogeophysical cycling of carbon (C), water (H2O), nitrogen (N), phosphorus (P), and sulfur (S). This decoupling is a causative factor of the increase in emissions of N2O and CH4, eutrophication and contamination of water resources, degradation of rangelands, and decline in its biodiversity. Therefore, identifying and adopting systems that integrate livestock with crops and trees are critical for reducing the environmental footprint of animal-based dietary products. Incorporating pastures/forages in the rotation cycle along with controlled grazing, called ley farming, and agroforestry, such as alley cropping, are examples of integrated farming systems. Other strategies of reducing the environmental footprint comprise the following: reducing enteric fermentation by precision feeding and matching dietary protein to animal need, processing CH4 and N2O emissions for other uses, and managing manure and other animal waste prudently. Other important considerations are adopting multiple GHG perspectives and minimizing gas swapping, reducing wastage of animal products, decreasing the use of antibiotics, and restoring rangeland for sequestration of atmospheric CO2 as soil organic matter.
... can return to the supplementary production charges, either those related to the herbicide, or those related to the harvest of alfalfa. According to Pousset (2008), Hawkins (2017), it is particularly economical for livestock to harvest the grass they consume. ...
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Our study focuses on comparing the effects of different technical itineraries-that are conventional tillage (CT), direct seeding on dead cover (DSDC), direct seeding on alive cover crop of Alfalfa with application of herbicide (DSAC+H) and direct seeding on alive cover crop of Alfalfa associated with sheep grazing (DSAC+G)-on the behavior of barley crop and on the evolution of soil fertility in a steppe region characterized by its dry climate, the brittleness of its soils and the large practice of ranching and cereal. Both soil and crop parameters were evaluated, and we made sure in which itinerary the best results are obtained, either for those linked to the soil (soil moisture and the storage of organic matter) or those related to the crop yield and the economic results. Bendaoud A, Masmoudi A (2019) Direct seeding mulch-based cropping systems associated with grazing as an alternative to conventional farming systems in the Algerian steppes. Eurasia J Biosci 13: 1691-1696.
Article
There is growing recognition of the need to achieve land use across the southern Australian rangelands that accommodates changing societal preferences and ensures the capacity of future generations to satisfy their own preferences. This paper considers the prospects for sustainable use of the pastoral lands based either on continued grazing or emerging, alternative land uses. After an overview of the southern rangelands environment, the status of the pastoral industry, its environmental impacts, and key issues for pastoral management, we propose four principles and 19 associated guidelines for sustainable pastoralism. Although some continued withdrawal of land from pastoralism is anticipated, we expect that pastoralism will continue throughout much of the region currently grazed, particularly in the higher rainfall environments in the east. Within these areas, sustainable pastoral land use should be achievable by the application of four broad management principles, as follows: (1) manage grazing within a risk management framework based on the concept of tactical grazing, (2) develop infrastructure to allow best management of both domestic and non-domestic grazing pressure, (3) incorporate management of invasive native scrub, where required, into overall, ongoing property management and (4) manage grazing to enhance biodiversity conservation at landscape scale. Application of these principles and guidelines will require the development of appropriate policy settings, particularly in relation to kangaroo management, climate change, and natural resource governance, together with innovative approaches to research, development and extension. Policy development will also be required if the new industry of carbon sequestration is to deliver socio-ecological benefits without perverse outcomes. Other emerging industries based on renewable energy or ecosystem services appear to have considerable potential, with little risk of adverse ecological consequences.
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While the impact of livestock grazing has been frequently assessed for grasses, little is known about how livestock affects tree seedlings and saplings. We explored the effects of goat, cattle, and camel browsing on the survival of Balanites aegyptiaca seedlings and saplings, a broadleaved evergreen tree species indigenous to Sudan, in Dinder Biosphere Reserve-Sudan (DBR). We used a stratified sampling design with four sites: GOA (mainly browsed by goats), CAT and CAM being mainly browsed by cattle and camels, respectively, while CON was a control area without any livestock browsing. We tested the survival, mortality, and recovery of seedlings and saplings across different sites. Our results revealed that mortalities of seedlings in GOA were almost four times higher than that of CAM and CON and twice that of CAT (F3,196 = 100.39, P < .001). Further, sapling mortality was three times higher in GOA than that observed in CAT and CON (F3,196 = 73.4, P < .001). We found that seedlings recover better than saplings, and, unexpectedly, goat browsing severely affected the natural regeneration of B. aegyptiaca in DBR compared to other livestock species. Our study findings contribute to sustainable forest management and show that particularly goat browsing needs to be suppressed for the conservation of vulnerable tree species.
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Rangelands provide ecosystem services that are economically and ecologically critical for humans. Globally, invasion of exotic grasses drives loss of biodiversity and resilience of rangelands. In South Texas, buffelgrass (Cenchrus ciliaris syn. Pennisetum ciliare [L.] Link), a C4 perennial grass, was brought from Africa for range improvement as early as the 1930s. Buffelgrass generally increases forage biomass for livestock yet reduces habitat suitability for wildlife. Interest in controlling buffelgrass has increased due to its negative impacts on iconic wildlife, such as whitetailed deer (Odocoileus virginianus, Zimmermann 1780) and northern bobwhite (Colinus virginianus, Linnaeus 1758). The objective of this study was to evaluate the effect of a targeted grazing strategy that used buffelgrass and plant community phenology as indicators to determine the timing of cattle movement. On two private ranches in different ecoregions, we tracked targeted grazing versus light grazing in native-dominated and buffelgrass-dominated plant communities across variable precipitation through five growing seasons. We measured the effects of grazing type, plant community type, and precipitation on buffelgrass cover, native plant species richness, foliar cover, and Shannon diversity. Targeted grazing had a strong impact on diversity, increasing 0.37 ± 0.07 from a mean of H = 1.29 under the targeted grazing management. Conversely, buffelgrass cover was negatively correlated with Shannon diversity, decreasing it by 0.075 ± 0.03 for every 10% increase in buffelgrass cover from a mean of H = 1.29. Despite a variability in precipitation across seasons and years (93−455 mm), targeted grazing improved species richness and cover of native plants throughout the study. Our findings suggest that targeted grazing shows promise as an adaptive grazing strategy that reduces the impact of buffelgrass across highly variable precipitation. In unpredictable environments, management techniques that improve the resilience of plant communities through preserving biodiversity are critical.
Article
Rangeland management approaches, including rotational grazing, rely on assumptions about plant growth responses to the intensity, or severity (sward height) plus frequency, of defoliation. We tested these assumptions at the farm, patch and plant scale using data from a grazing management trial in an Eastern Cape mesic grassland of South Africa along with field plot and glasshouse pot experiments. The grazing trial tested season-long grazing (SLG), four-camp grazing (FCG) and holistic planned grazing (HPG) at equivalent stocking rates over three years. We found that grass growth responses in both potted plants and field plots were reduced under more frequent and severe defoliation but that this was mitigated under elevated soil nutrients, in line with the Compensatory Continuum Hypothesis which predicts that compensatory growth will increase across an increasing fertility gradient. In the farm trial, SLG, which theoretically causes high frequency, low severity defoliation, reduced bare ground cover and increased vegetation greenness with increasing defoliation intensity on nutrient-rich soils. This effect was not present under FCG or HPG and disappeared under very high defoliation intensities and on relatively water- and nutrient-poor soils. Managers are advised to only increase grazing frequency on relatively high nutrient soils, while maximizing recovery on poorer nutrient soils.
Article
Context Scientific and anecdotal reports conflict on the effects of intensive rotational grazing (IRG) on cattle growth, and very limited objective data are available from cattle grazing in northern Australia that producers can use to decide whether to adopt IRG. Aims This study aimed to compare liveweight gain and sequestration of soil organic carbon when cattle grazed buffel grass (Cenchrus ciliaris L.) under either continuous grazing (CG) or IRG. Methods In each year of this 9-year study, a cohort of Brahman and Brahman-cross weaners was randomly allocated to IRG and CG treatments. They grazed predominantly buffel pasture at Douglas Daly Research Farm from shortly after weaning for about a year, at which time they were replaced by the next year’s group, and the average liveweight gains of the treatments over the post-weaning year were compared each year for 9 years. Soil organic carbon was measured in the topsoil (0–30 cm) twice each year for 5 years (2009–14) and changes in carbon stocks over time were compared between treatments. Key results In each year of this study, the growth of cattle grazing buffel pasture was lower under IRG than CG. In each year, liveweight gain was lower (P < 0.05) per head and per hectare under IRG. Topsoil soil organic carbon stocks did not increase in the IRG treatment over the 5 years of this study. Conclusions This study found that cattle growth, both per head and per hectare, was lower under IRG than CG, and that IRG did not result in any increase in soil organic carbon over time. Implications The lower per head and per area production from the IRG system, combined with the extra infrastructure and operating costs for IRG systems, make it unlikely that adoption of IRG would improve the profitability of cattle-grazing operations on similar pasture systems in northern Australia. However, the findings of this study may not apply to other pasture systems and environments.
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Anthropogenic disturbance has generated a significant loss of biodiversity worldwide and grazing by domestic herbivores is a contributing disturbance. Although the effects of grazing on plants are commonly explored, here we address the potential multi‐trophic effects on animal biodiversity (e.g. herbivores, pollinators and predators). We conducted a meta‐analysis on 109 independent studies that tested the response of animals or plants to livestock grazing relative to livestock excluded. Across all animals, livestock exclusion increased abundance and diversity, but these effects were greatest for trophic levels directly dependent on plants, such as herbivores and pollinators. Detritivores were the only trophic level whose abundance decreased with livestock exclusion. We also found that the number of years since livestock was excluded influenced the community and that the effects of grazer exclusion on animal diversity were strongest in temperate climates. These findings synthesise the effects of livestock grazing beyond plants and demonstrate the indirect impacts of livestock grazing on multiple trophic levels in the animal community. We identified the potentially long‐term impacts that livestock grazing can have on lower trophic levels and consequences for biological conservation. We also highlight the potentially inevitable cost to global biodiversity from livestock grazing that must be balanced against socio‐economic benefits. Livestock grazing reduces the abundance and diversity of animals, but the effects are dependent on trophic level of responding species. Herbivores and pollinators are most impacted, while detritivores increase with livestock present. There is also an effect of livestock exclusion over time on the animal community.
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We evaluated the adequacy of rotational grazing to improve rangeland condition in the Flooding Pampa region, eastern Argentina, comparing the floristic composition dynamic of the 2 main plant communities under rotational and continuous grazing over a study period of 4 years (1993-1996). The experiment was conducted in commercial farms located in 4 sites of the Flooding Pampa region. In each site, a couple of farms, one managed under rotational grazing (implemented in 1989) and an adjacent one managed under continuous grazing at a similar stocking rate (1 AU ha-1), constituted the replications of the experiment. Basal cover of species, litter, and bare soil were monitored in midslope and lowland grassland communities on each farm. Total plant basal cover in midslope and in lowland communities remained unchanged over the whole experimental period under both grazing methods. Under rotational grazing, litter cover was higher in both communities while the amount of bare soil showed a significant reduction in lowlands and a tendency to be lower in midslope. Basal cover of legumes, C3 annual and C3 perennial grasses was higher, while cover of C4 prostrate grasses was lower under rotational grazing in the midslope community. In the lowland community, rotational grazing effects were evident only in the drier years, when higher cover of hydrophytic grasses and legumes and lower cover of forbs occurred. Plant species diversity did not change in response to grazing. In conclusion, rotational grazing promoted functional groups composed of high forage value species and reduced bare soil through the accumulation of litter. These changes indicate an improvement in rangeland condition and in carrying capacity. As the stocking rate was approximately 60% higher than the average stocking rate of the Flooding Pampa region, we believe that productivity and sustainability may be compatible by replacing continuous with rotational grazing.
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Over 3 billion hectares of lands worldwide are grazed by livestock, with a majority suffering degradation in ecological condition. Losses in plant productivity, biodiversity of plant and animal communities, and carbon storage are occurring as a result of livestock grazing. Holistic management (HM) has been proposed as a means of restoring degraded deserts and grasslands and reversing climate change. The fundamental approach of this system is based on frequently rotating livestock herds to mimic native ungulates reacting to predators in order to break up biological soil crusts and trample plants and soils to promote restoration. This review could find no peer-reviewed studies that show that this management approach is superior to conventional grazing systems in outcomes. Any claims of success due to HM are likely due to the management aspects of goal setting, monitoring, and adapting to meet goals, not the ecological principles embodied in HM. Ecologically, the application of HM principles of trampling and intensive foraging are as detrimental to plants, soils, water storage, and plant productivity as are conventional grazing systems. Contrary to claims made that HM will reverse climate change, the scientific evidence is that global greenhouse gas emissions are vastly larger than the capacity of worldwide grasslands and deserts to store the carbon emitted each year.
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Grazing system and stocking rate effects on forage standing crop of tallgrass prairies in north-central Oklahoma were evaluated from 1989 to 1993. Twelve experimental units, consisting of pastures dominated by big bluestem [Andropogon gerardii Vitman], little bluestem [Schizachyrium scoparium (Michx.) Nash], indiangrass [Sorghastrum nutans (L.) Nash], and switch-grass [Panicum virgatum L.], were arranged in a completely randomized design with either a short duration rotation or continuous grazing system and stocking rates ranging from 127 kg animal live-weight/ha to 222 kg live-weight/ha. Yearling steers grazed the units from late April to late September. Herbage standing crop was sampled in July and September. Total, live, and dead standing crops did not differ significantly between the 2 grazing systems in July. Total standing crop was significantly higher in the rotation units in September (3,600 versus 3,020 kg/ha, P
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Short-duration grazing (SDG) has been purported to increase forage production and utilization compared to other grazing systems, and thus can sustain higher stocking rates. This study was designed to determine if standing crop could be maintained as stocking rates increased. Four stocking rate treatments ranging from the recommended rate for moderate continuous grazing to 2.5 times the recommended rate were applied in a simulated 8-pasture SDG system. There was little change in frequency and composition of short-grasses over the study, but mid-grass frequency and composition both declined. Standing crop of all major forage classes declined as stocking rates increased. However, the rate of decline was less than proportional to the increase in stocking rate during the growing season. By fall, standing crop was inversely proportional to stocking rate, leading us to conclude that standing crop could not be maintained at the higher stocking rates. Low standing crop in the fall indicated a potential shortage of forage at the high stocking rates during the winter.
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