Our burning planet: why we must learn to live with fire, Pyne 2020
Steven J. Pyne is an emeritus professor at Arizona State University and the author of several books on fire history and policy. He wrote this opinion piece as a protest against the prevention and suppression of wildfires in our land management process. He argues that revising our perception of fire and accepting its presence in ecosystems is critical to our ongoing relationship with our planet.
He describes “a paradox at the core of Earth’s unraveling firescapes,” that “we have too many bad fires — fires that kill people, burn towns, and trash valued landscapes. We have too few good ones — fires that enhance ecological integrity and hold fires within their historic ranges” [Pyne 2020]. Operating under a paradigm of total fire suppression leads us astray in managing landscapes, while we so readily accept fire in the form of fossil fuel combustion in so much of our lives. Pyne sees these behaviors as evidence that our relationship with fire is out of whack.
He stresses the importance of distinguishing between burning in living ecosystems and burning the fossils of life from past ages.
The critical contrast lies in a deeper dialectic than burned and unburned landscapes. It is a dialectic between burning living biomass and burning fossil biomass. We are taking stuff out of the geologic past, burning it in the present with all kinds of little understood consequences, and passing the effluent into the geologic future.
…
Fires in living landscapes come with ecological checks and balances. Fires in lithic landscapes have no boundaries save those humans impose on themselves [Pyne 2020].
Pyne associates three paradoxes with our current fire policies. First, abandoning a traditional lore of “light burning” has removed good fires and left us with only bad and harmful ones. When controlled burns are not practiced regularly to manage landscapes, vegetation can build up and fuel the intensity and spread of uncontrolled blazes that spark.
Second and surprisingly: “The Earth does not have more fire today than before fossil fuels emerged as a primary source of energy: It has significantly less” [Pyne 2020]. That is, the amount of land burned in fires has actually decreased, while the presence of intense “feral flames” has increased. The decrease in the scope of fire is largely due to the move away from fire’s use in agriculture and its replacement with modern techniques, including machinery powered by combustion. As Pyne describes,
Farmers had relied on fire to fertilize, fumigate, and alter microclimates. Fire did all this in one catalytic process that self-propagated. But with the transition to fossil biomass, modern agriculture found surrogates with artificial fertilizers, pesticides, and herbicides, and it now had the fossil-fuel-powered machines to distribute them. Production became more efficient; transport, more dense. As agriculture joins a modern economy, working flames recede [Pyne 2020].
What we are left with is intense, destructive wildfire, rather than helpful working fire. Pyne points out that we now only see one half of fire’s possibilities, since the working fire shaping landscapes and agricultural systems is notably absent. He says: “Landscape fire fades; what fire persists tends to be outbreaks of feral fire. We see those oft-disastrous flames. We don’t see the lost fires or the sublimated fires in machines that removed them” [Pyne 2020].
The third paradox is that as we reduce our use of fossil fuels going forward (as one sort of fire), we will have a greater need “to manage fire in living landscapes.” So Pyne calls for us “to reinstate the right kind of fire, and … adapt to fire’s presence and let it do the work for us.” He pushes for the recognition that transitioning away from our reliance on fossil fuel burning is an important but incomplete step in balancing ecosystem health. Fires in living systems have an important role to play, and according to Pyne, “the need is not just to reduce fuels to help contain wildfires; those missing fires did biological work for which no single surrogate exists” [Pyne 2020]. He asserts that we will need to reintroduce fire as a staple tool on our landscapes.
Fires in living systems have an important role to play, and according to Pyne, “the need is not just to reduce fuels to help contain wildfires; those missing fires did biological work for which no single surrogate exists.” He asserts that we will need to reintroduce fire as a staple tool on our landscapes. |
Pyne concludes with a call for the overhaul of our conceptual and policy treatment of fire.
Anthropogenic fire needs more room to maneuver – more geographic space, more legal space, more political space, more conceptual space. … Equally, society needs to rethink liability law to reduce the risks incurred by fire officers doing a necessary job …; adapt air quality regulations …; and tweak National Environmental Policy Act review processes … [to] accommodate the realities of restored fire at a landscape scale. … Communities in the fire equivalents of floodplains need hardening [Pyne 2020].
He proposes that fire restoration jobs can replace those lost from forestry and fire suppression. He admits that our understanding of fire biology requires more research, and that our greatest need is for “a working fire culture … that ensures fire’s proper place in the landscape” by renewing “our ancient alliance” with fire and making it “an indispensable friend.”
Fire Myths, Hanson 2018
In this podcast interview, Dr. Chad Hanson, an ecologist and fire researcher, shares his perspective on the 2018 wildfires in the American West and some myths that have circulated about fire management in their wake.
First, there is a perception that wildfires in forested regions are so devastating that they reverse the ‘carbon sink’ effect of forests, releasing the carbon of the burned biomass back into the atmosphere. Forests still sequester large amounts of carbon, even if they experience wildfires, because most of the forest remains intact even through blazes. Models that fault wildfires for turning forests into net carbon emitters rest on the assumption that all of the carbon that would usually be stored in a forest is combusted during a fire, but this is far from the reality, in which just a small fraction of a forest’s biomass is consumed. As Hanson says,
In fact, even in the most intensely burned patches where a fire kills all the trees (which in reality, even in the biggest fires, it’s only a small portion, a minor portion of the overall fire)… But even in those areas, only about two or three percent of the above ground biomass is actually consumed, in other words, ends up as carbon. The trees are still standing there [Hanson 2018].
Second, the intensity of fires has not been universally increasing in recent years. We are experiencing a lot of geographically large fires, but these are not necessarily high intensity fires. The percentage of high intensity fire today is similar to historical precedent, and overall, there is much less fire in our landscapes now than in Earth’s geological history. Further, even in the highest intensity fires, forests are never decimated past the point of no return. Trees and vegetation are reestablished after fires, and the ash left behind is dense with nutrients, promoting new growth. Even dead trees, which have long been thought to be responsible for contributing to high intensity fires, are actually not shown to drive fire intensity, according to Hanson.
This series of myths – that forest fires are raging with high intensities, that they burn up so much biomass as to make forests ineffective sources of carbon sequestration, and that the only way to manage forests to avoid these outcomes is to thin out the trees – hinder our understanding of forest management and allow false and harmful solutions to propagate. As a result of these perceptions, proponents of logging have pushed to expand logging operations, purportedly as a fire management strategy. However, according to Hanson, logging is actually linked to greater fire intensity. He explains that small materials, like twigs, are more flammable than trunks.
Tree trunks are not combustible. They really just don’t burn. Again, outer bark can burn, but the trees themselves don’t burn. What logging does is it removes noncombustible material essentially from the forest and leaves behind very combustible kindling, like slash debris – the branches and small twigs and things like that that are not possible to get up off the forest floor after the tree trunks are removed and that’s very combustible.
The other thing that logging does is that it reduces the cooling shade of the forest canopy. By removing a lot of trees, you have more sunlight reaching the forest floor, and what that does is it creates hotter and drier conditions and that means everything on the forest floor gets more dried out, more potentially combustible, and logging also spreads invasive weeds like cheatgrass, which is very, very flammable. Cheatgrass loves a lot of sunlight and so you get a lot of that after intensive logging.
And the last [problem with logging] is a little bit more technical, but basically when you have a lot more trees, it cuts down on the wind speeds that drive fires. It has a buffering effect in a sense. And when a lot of the trees are removed, that buffering effect is reduced or eliminated and fire spreads through those forests faster [Hanson 2018].
This three-fold effect of logging makes forests more vulnerable, and it is important to dispel the concept that removing trees is the best way to keep people safe from fires. Hanson criticizes the opportunism of using these fire myths to advance an agenda of logging. He cautions that when fire science and policy emerge from the U.S. Forest Service, which manages national forests and gains a good deal of revenue from logging, there is a perverse incentive to keep practicing logging as fire management. He calls for clearer and more public communication from scientists to dispel fire myths and share recent findings that have been shifting so much of what we know about fire science.
Hanson says that the best strategy to ensure the protection of homes from wildfire is to focus on the homes themselves. This can be done by using fire resistant building materials, fire-proofing roofs, erecting rain gutter guards to prevent the accumulation of small fuels like pine needles, pruning the vegetation in a 100-foot radius of a house, and removing small shrubs and branches of mature trees, while leaving those trees standing. Fire management interventions at this level are shown to be far more effective at preventing damage than attempts to control the fuel load of fires within forests.
Hanson points out the need to decouple fires that occur in remote forest ecosystems and those that rage through human settlements and urban communities, because thinning out vegetation in attempts to suppress the former do not actually protect against the latter. In fact, thinning forests undermines the ecological processes that fire serves in forest systems. When discussing fires that have devastated homes and lives, he says
I mean, where’s the forest in Malibu? There’s no forest. These are chaparral ecosystems, most of the fires that are burned homes and lives have been lost are not in forest. In fact, they’re mostly nowhere near forests. They’re in grasslands, chaparral shrub habitat, oak woodlands. But the areas that are in forest, where we’ve had tragic loss of homes and lives, these are mostly areas where we’ve had intensive logging, and it’s like I mentioned earlier, you know, more logging is typically associated with more intense fire at a faster rate of spread. [Hanson 2018]
He advocates for a greater focus on fire prevention around homes and communities themselves, in what is known as ‘defensible space.’ He points out that such measures are a great source of jobs, as well as an effective intervention curbing the destructiveness of fires. With a shift in focus from forest thinning to fire-proofing, and better understanding and communication of fire science, we can let go of some of the fire myths that have been dictating policy and failing to meet public needs.
More logging is typically associated with more intense fire at a faster rate of spread [Hanson 2018]. |
Land use planning and wildfire: development policies influence future probability of housing loss, Syphard et al. 2013
Wildfire is a challenge that threatens human settlement at an increasing scale, but planning and development does not always address this threat. In fact, policy around land use is in large part responsible for the destruction of homes and property and the threat to human life that occurs in wildland-urban interfaces (WUIs). While there is much literature on how to suppress fires, mitigate their damage, or manage for less destructive fire seasons, a more far-reaching strategy would be to stop building in fire prone areas. Land use decisions can be improved to lessen the risk of infrastructure loss and foster healthy ecosystem function.
Land use planning is an alternative that represents a further shift in thinking, beyond the preparation of communities to withstand an inevitable fire, to preventing new residential structures from being exposed to fire in the first place. The reason homes are vulnerable to fires at the wildland-urban interface is a function of its very definition: “where homes meet or intermingle with wildland vegetation”. In other words, the location and pattern of homes influence their fire risk, and past land-use decision-making has allowed homes to be constructed in highly flammable areas. [Syphard 2013: 1-2]
In many areas, including in California, we have come to expect fire, but have not necessarily learned to live with it. The authors of this study analyzed what types of human development carried out in the next several years might contribute to or avert the risk of fire damage. They examined the South Coast Ecoregion of San Diego County, which they describe as:
topographically diverse with high levels of biodiversity, and urban development has been the primary cause of natural habitat loss and species extinction. Owing to the Mediterranean climate, with mild, wet winters and long summer droughts, the native shrublands dominating the landscape are extremely fire-prone [Syphard et al. 2013: 2].
This study acknowledges the responsibility humans have in shaping the landscape and its biodiversity, and in contributing to fire activity by building into wild areas and expanding WUI. They sought to understand how patterns of development and housing density might influence future fire spread and intensity. They found that
structures in areas with low- to intermediate- housing density were most likely to burn, potentially due to intermingling with wildland vegetation or difficulty of firefighter access. Fire frequency also tends to be highest at low to intermediate housing density, at least in regions where humans are the primary cause of ignitions [Syphard 2013: 2].
Though it is impossible to reverse the effects of policies that have shaped the fire landscape we have today, understanding the way human behavior contributes to our own risk of harm from wildfire can help us plan intelligently going forward. The authors conclude that
With projections of substantial global change in climate and human development, we recommend that land use planning should be considered as an important component to fire risk management, potentially to become as successful as the prevention of building on flood plains. History has shown us that preventing fires is impossible in areas where large wildfires are a natural ecological process. As Roger Kennedy put it, “the problem isn’t fires; the problem is people in the wrong places [Syphard 2013: 10-11].
Community owned solutions for fire management in tropical ecosystems: case studies from Indigenous communities of South America, Mistry et al. 2016
Indigenous groups across the world have developed ecological knowledge linked to the places they inhabit, including prescribed fire practices used to maintain healthy ecosystems. Mistry et al. examine the challenges Indigenous communities in South America face in managing the landscape through fire and preserving such knowledge across generations in sometimes hostile political climates. However, there is growing recognition that Indigenous people have a vital role to play in combating climate change and supporting biodiversity and healthy ecosystems.
Emerging research shows the fundamental role of Indigenous land-use practices for controlling deforestation and reducing CO2 emissions—analysis of satellite imagery suggests that Indigenous lands have reduced rates of deforestation and habitat conversion, and lower greenhouse gas (GHG) emissions, compared with surrounding areas [Mistry 2016: 1].
While indigenous groups’ use of prescribed fire early in the dry season to prevent destructive out-of-control fires is gaining broad recognition, that hasn’t necessarily translated into greater respect or autonomy for those communities. Instead, Indigenous people may be given auxiliary roles in fire management, or have their knowledge utilized but implemented by non-local organizations in structures that fail to benefit or empower the local communities themselves. While this may still achieve desired wildfire management results, it weakens intergenerational knowledge transfer and undermines the social and spiritual role of prescribed fire within communities.
Mistry et al. argue that “Indigenous fire management is effective in that it is an emergent property of a linked social-ecological system where Indigenous knowledge and culture, and associated livelihoods, are intimately interconnected with landscape management practices” [Mistry 2016: 4]. Precisely because prescribed fire matters to Indigenous communities as something more than a tool in the toolkit of managing wildfires, it is effective when carried out by those communities in reducing risk of destructive wildfires and supporting healthy and biodiverse ecosystems.
Importantly, the numerous uses of fire mean that burning is a relatively constant activity, particularly during the dry season, generally at low levels, thereby helping to prevent the build-up of flammable fuel and incidents of large-scale uncontrollable wildfires. Experimental studies of fire behaviour suggest that this patch mosaic burning not only reduces the occurrence of dangerous fires, but also increases spatial and temporal vegetation heterogeneity and biodiversity [Mistry 2016: 4].
These authors distinguish between Indigenous relationships to ecosystems and market-based approaches to ecosystem services valuation, which attempt to incentivize conservation through payment. While the goal of the market-based approach is to monitor and preserve functioning ecosystems, “their ideological foundations within a neoliberal agenda that promotes ‘selling nature to save it’ is in stark contradiction with Indigenous ontologies based on human–nonhuman–spiritual relationships” [Mistry 2016: 2].
Within Indigenous communities, fire plays a role in social bonding, intergenerational knowledge transfer, and agricultural practices. Mistry et al. argue that
savanna and forest ecosystems are being protected within Indigenous lands not because they are being ‘managed’ in a direct and active way, but as the indirect outcome of a healthy social–ecological system, i.e. the outcome of practices that maintain social and ecological integrity, or what can be termed ‘community owned solutions [Mistry 2016: 4].
But challenges, including loss of fire knowledge by younger generations within Indigenous groups because of outside pressures and encroachment, pose a threat to these fire management practices. For example, in Venezuela and Brazil,
young Wapishana and Makushi and some community leaders were more critical about the use of fire as they had more regular contact with state natural resource management officials and environmental organizations that promoted antifire discourses. As with the Krahô, changing Indigenous values to focus on fire prevention and suppression could have the effect of making the problem worse [Mistry 2016: 4].
That is, when prescribed burning is taken out of its original context and represented to younger generations of Indigenous people and land stewards as simply a well-incentivized tool, the Indigenous communities themselves are diminished, along with the robustness of their ecological knowledge that gets passed forward.
In spite of lingering antagonistic views in Brazil and Venezuela toward indigenous fire management, attitudes are changing.
Not only is there a move away from categorizing all fire as ‘bad’; there is also a recognition that Indigenous fire knowledge is a valid form of knowledge that could inform policy-making [Mistry et al. 2016: 6].
Mistry et al. suggest the best way to achieve both ecological and communal health might be through power-sharing arrangements. By empowering Indigenous communities, national governments could in turn work toward their fire management and biodiversity conservation goals. This might require evaluating ecological health in ways beyond just quantitative metrics, which reduce these complex systems down to a set of standardized numbers, as well as the recognition that the well-being of these ecosystems is tied to the Indigenous communities that inhabit them, according to the authors:
There needs to be enabling policies that focus on legitimizing and strengthening Indigenous fire management as a community owned solution. Critically, as community owned fire management is intricately linked with Indigenous survival strategies, so too must firefighting and prescribed burning be grounded in local social–ecological systems. We believe it is necessary to define long-term actions to support the integrated functioning and survival of Indigenous communities as a whole, rather than focusing on isolated issues (e.g. carbon retention) or benefits for some individuals (e.g. hiring Indigenous firefighters) [Mistry 2016: 8].
This systems approach may well be the key to successful long-term fire management. The authors offer this challenge:
What we want to do is not promote one over the other, but encourage decision-makers to engage with, and appreciate, Indigenous perspectives and worldviews on fire management. Community owned solutions acknowledge collectivity, spirituality, process orientation and locality, whereas many expert-led fire management interventions often result in promoting individualism, ethnocentrism, rationality, efficiency, commercialism and globalization. The question we raise is this: can the ‘community owned solutions’ approach be the mechanism through which Indigenous perspectives can be represented within fire management [Mistry et al. 2016: 8]?
Invasive grasses increase fire occurrence and frequency across US ecoregions, Fusco et al. 2019
It has long been suspected that the increasing abundance of invasive grass species may contribute to wildfires in the United States by adding abundant new fuels to ecosystems, increasing the range of conditions that lead to fire ignition, and enabling the development of larger, hotter fires. The new fire regimes (patterns of fire duration, intensity, and spread) that emerge can in turn destabilize wildlife and lead to local extinctions while expanding favorable habitat for the invasive species, for many of these grasses recover quickly after fires, providing renewed fuel and potentially increasing the frequency of fires.
The authors of this paper provide a comprehensive analysis on the impact of 12 non-native grasses on the occurrence (whether a fire occurred in a particular place), frequency (how many times a place burned), and size of wildfires. The research was conducted across 29 US ecoregions, including deserts, temperate forests, wetlands, woodlands, river valleys, shrublands, and coastal plains. Data were collected and combined from fire records and records of invasive grasses, and results from “invaded” regions and nearby “uninvaded” regions were compared. The authors also considered human activities and ecological factors related to fire.
One of the most notorious impacts of nonnative, invasive grasses is the alteration of fire regimes. Yet, most evidence of these impacts comes from local-scale studies, making it unclear whether they have broader implications for national and regional fire management. Our analysis of 12 invasive grasses documents regional-scale alteration of fire regimes for 8 species, which are already increasing fire occurrence by up to 230% and fire frequency by up to 150%. These impacts were demonstrated across US ecoregions and vegetation types, suggesting that many ecosystems are vulnerable to a novel grass-fire cycle. Managing existing grass invasions and preventing future introductions presents a key opportunity to remediate the ecological and economic consequences of invasive species and fire [Fusco 2019: 23594]
The results of this analysis showed that 8 of the 12 invasive grass species examined were associated with significantly higher fire occurrence and fire frequency, and that fire occurrence more than doubled for two of these species. Three of the species did not impact fire occurrence, and a decrease in fires was associated with one species (a wetlands grass species). The impact on fire size was variable, with two species associated with larger fires, three species associated with smaller fires.
Individually, climate change is expected to increase the potential for fire occurrence by 150% by the end of the century based on projected changes in temperature and precipitation. Here we show that 8 invasive grass species are already associated with increased rates of fire occurrence by 27 to 230%, and 6 invasive grass species are associated with increased mean fire frequency by 24 to 150%, compounding current and future fire risk across the United States. [Fusco et al. 2019: 23595]
The authors suggest that fire and invasive species managers work together to create integrated management plans; otherwise, the convergence of human activities, climate change, and invasive species will continue to promote wildfires across the United States.
Smokey the Beaver: beaver‐dammed riparian corridors stay green during wildfire throughout the western USA, Fairfax and Whittle 2020
This study examines the positive effects of beaver damming on the resistance of landscapes to wildfire damage. The authors find that in riparian corridors (areas along rivers), the presence of beavers and their dams can create refuges that withstand blazes that consume surrounding vegetation.
Beavers play an important role in wetland habitats and are known as ecosystem engineers for the way they can shape landscapes with their activities. Beaver dams slow down water moving across a landscape, holding it in place for longer and allowing water to infiltrate into the soil, which raises water tables.
The combination of building flow obstructions (dams), accumulating water (ponds), and spreading that water out in the landscape (channels) gives beavers the unique potential to modulate environmental extremes such as flood and drought. When it comes to water, beavers slow it, spread it, and store it.
Due to the fact that beaver channels and dams spread water out in the landscape and store it broadly in adjacent soils, the vegetation near beaver ponds doesn’t experience as much reduced water availability during drought. Drought-stricken vegetation burns more easily than lush, green vegetation, so it follows that the vegetation around beaver ponds would be more difficult to burn than vegetation around undammed creeks [Fairfax and Whittle 2020: 1].
Fairfax and Whittle observed the effects of beaver dams on preventing fire spread to the areas where they had built dams, examples of which are shown in satellite imagery below.
The authors quantify the effects of beaver activity in fireproofing areas by examining the Normalized Difference Vegetation Index (NDVI) observed in satellite imagery before, during, and after wildfire years in the American West. They found that while vegetation is able to reestablish itself a year after fire damage regardless of beaver activity due to its own resilience to fire, areas in beaver dammed zones maintained vegetation even during wildfires, demonstrating actual resistance to blazes, not just the ability to recover after damage. They note how vital this is for those ecosystems and the life within them.
These ribbons of fire-resistant riparian corridor may be particularly important for species that are unable to physically escape wildfire. They can provide temporary habitat for fish, amphibians, reptiles, small mammals, wild and domestic ungulates, and birds that are unable to outrun/outfly the spread of flames. While we found that beaver activity does play a significant role in maintaining vegetation greenness during wildfires, it does not appear to play a significant role in the ability for a riparian corridor to rebound in the year following fire. Riparian vegetation NDVI rebounded in the year following the fire regardless of proximity to beaver activity. Thus, we would describe beaver activity as creating refugia during wildfire, but not necessarily changing the long-term landscape outcomes [Fairfax and Whittle 2020: 7].
The survival of wildlife is crucial to these ecosystems, and beaver activity uniquely contributes to the creation of refuge areas that resist burning and can provide shelter for animals during these destructive events. The authors conclude,
As it stands today, wetland habitat is very limited and beavers can create and maintain wetland habitat that persists through flood, drought, and, as we have shown in this study, fire. This has immediate relevance to scientists and practitioners across North America and Eurasia, particularly in places with increasing wildfire risk and existing or planned beaver populations. Perhaps instead of relying solely on human engineering and management to create and maintain fire-resistant landscape patches, we could benefit from beavers’ ecosystem engineering to achieve the same goals at a lower cost [Fairfax and Whittle 2020: 7].
Planned Herbivory in the Management of Wildfire Fuels, Nader et al. 2007
Nader et al. survey herbicides, prescribed fire, mechanized treatments, hand cutting, and grazing animals as fire management techniques. Managing vegetation involves “changing the plant community to decrease the flame height when fire occurs,” favoring native species that may be more resilient to fire, and altering the landscape to create fuel breaks, which are patches across which it is hard for fire to jump [Nader 2007: 18].
Focusing their analysis on grazing and the contexts in which it is most useful, the authors note that there are many site and animal specific factors to take into account for successful implementation.
[Grazing] is a complex, dynamic tool with many plant and animal variables, and it requires sufficient knowledge of the critical control points to reach treatment objectives. Those control points involve the species of livestock grazed (cattle, sheep, goats, or a combination); the animals’ previous grazing experience (which can affect their preferences for certain plants); time of year as it relates to plant physiology (animal consumption is directed by the seasonal nutrient content); animal concentration or stocking density during grazing; grazing duration; plant secondary compounds; and animal physiological state [Nader 2007: 19].
Grazing has the advantage of keeping nutrients in the ecosystem, unlike mechanical methods that harvest vegetation to be sold as biomass chips (like wood chips). This means that when animals digest vegetation and excrete on the landscape, they participate in the local nutrient cycle. Animals also trample soil, which can crush fine fuel and mix it into the soil, where it cannot contribute to ignition, which reduces one contributing factor to persistent and destructive blazes. Animals do more than just remove extra vegetation – they can have many beneficial interactions within a given ecosystem.
Any grazing plan designed for fuel reduction needs to consider the grazing impacts on parameters other than just simply reduction. The effects of the grazing management should be studied for their impact on water quality, compaction, riparian vegetation, disease interaction with wildlife (bluetongue, pasturella), and weed transmission. The positive aspects of grazing over other treatments also should be weighed, including recycling of nutrients into the products of food and fiber [Nader 2007: 22].
By introducing grazing animals into a landscape or agricultural system, managers can affect biodiversity in complex ways. The authors mention that “Hadar et al. reported that light grazing increased plant diversity on treated sites. Thus, when proposing a stocking rate for treatment consumption, the environmental impact needs to be considered” [Nader 2007: 22].
Nader et al. conclude that “grazing is best used when addressing vegetation with stems of smaller diameters that make up the 1- and 10-hour fuels. These two fuel classes are important because they can greatly impact the rate of spread of a fire, as well as flame height” [Nader 2007: 19]. While they call for further research to validate anecdotal accounts supporting grazing and understand its best practice, they maintain that “prescribed grazing has the potential to be an ecologically and economically sustainable management tool for reduction of fuel loads” [Nader 2007: 20].
Landscape rehydration ‘better than dams’ in improving farm production, reducing fire risk, Major 2020
A project in Queensland, Australia has met with success in its efforts to rehydrate the landscape on the farmland property of Worona Station, improving biodiversity, water retention, and resistance to erosion and fire. Worona Station had been degraded and faced serious erosion issues, so Chris Le Feuvre, the owner, partnered with consultancy groups of NQ Dry Tropics and the Mulloon Institute in a project to rehydrate his land.
The project team has used a combination of planned grazing and small, low-tech dams to combat erosion problems. The grazing technique involves:
Splitting paddocks into small sizes and using large mobs of cattle grazing on rotation … grazing pasture more intensively while giving it longer to rest, [thereby] increasing carrying capacity.
Grazing in this way (which is evocative of Allan Savory’s Holistic Planned Grazing methodology) has resulted in increased pasture species diversity and boosted plant growth, allowing the Le Feuvre to double his herd size. Planned grazing has also reduced sediment runoff from the property. Sam Skeat, a grazing officer with NQ Dry Tropics, attests to the importance of grazing.
The plug-and-pond technique — also known as leaky weirs — involves small dam-like structures to lift the bed level of the water, which is then run onto the floodplain to grow pasture and recharge aquifers. While weirs have been strategically constructed, Mr. Skeat said grazing management was the most important tool to improve water retention in a landscape. ‘If you can use cattle as a tool to regenerate the grassland, you’ll get more infiltration, slow the flow, hold water up in the landscape and have you growing grass for longer’ [Major 2020].
Rehydrating landscapes can improve their resilience to extreme events, and improve their quality in the face of chronic problems like erosion. According to the Mulloon Institute Chairman Gary Nairn, the issue of degraded gullies and streams is a national concern. Gullies are created when parched land is unable to absorb rainwater, allowing it to run off. The sediment-filled runoff ends up in the ocean, polluting it.
Nairn sees land rehydration through planned grazing and related techniques as a better solution than building a massive, industrial-scale dam to retain water. The Australian government has been looking into building new large dams. Levels at Warragamba Dam, which supplies about 80 percent of Sydney’s water, have dropped to less than half capacity.
‘We’ve been able to demonstrate in Mulloon, if we repaired and rehydrated the catchment through to the Sydney water supply, you could store the equivalent of Warragamba Dam,’ he said [Major 2020].
Well-watered mulberry tree credited with saving home on NSW South Coast from summer bushfires, Aubrey 2020
A well-watered mulberry tree has been credited with averting the danger of destructive wildfires from destroying Brett Hawkins’ home during 2020’s unprecedented fire season in Australia. When massive fires raged through the bush through the summer, many homes were completely engulfed. However, Hawkins attested that when he returned to his home after evacuating,
‘I could see straight away the house was intact — the roof was intact, but everything else around it was burnt, with the exception of the mulberry tree.’ He described the stark scene greeting him upon arriving back home, ‘It was apocalyptic,’ Mr. Hawkins said. ‘There was not a tree left, ash on the ground and smouldering embers everywhere.’ But among the blackened trees, Mr. Hawkins found his mudbrick house and mulberry tree in full leaf [Aubrey 2020].
In the season’s drought, he had been rationing water, but sparing some to keep his tree hydrated and healthy, which may have been a contributing factor in its resistance. According to the article, “Mr. Hawkins believed that by heavily watering the tree, combined with luck regarding which direction the fires came, the full heat of the bushfires was shifted.” [Aubrey 2020]
Another important feature is the mulberry’s lack of dried leaves and brush at its base that might pose a danger of igniting. Other species, like eucalyptus, with oily leaves that could dry out, or pine trees whose long branches catch dry leaves, are less ideal.
A tree expert from the Fenner School of Environment at the Australian National University analyzed some of the possible factors leading to the survival of this mulberry tree and what it might teach those wishing to fortify the fire resilience of their homes and properties. “While there does not seem to be a clear answer on what to plant to ‘fire-proof’ your house, Professor Brack said a well-watered tree, with a clear trunk and no loose, dry leaves or branches is a good start” [Aubrey 2020].
Aubrey, Kate, 2020, Well-watered mulberry tree credited with saving home on NSW South Coast from summer bushfires, ABC News, https://www.abc.net.au/news/2020-10-26/mulberry-tree-saves-home-from-bushfire/12813892.
Fairfax, Emily & Whittle, Andrew, 2020, Smokey the Beaver: beaver‐dammed riparian corridors stay green during wildfire throughout the western United States, Ecological Applications 30(8), https://doi.org/10.1002/eap.2225.
Fusco, Emily et al., 2019, Invasive grasses increase fire occurrence and frequency across US ecoregions, PNAS 116 (47), https://doi.org/10.1073/pnas.1908253116.
Hanson, Chad, Fire Myths, Podship Earth: November 25, 2018, podcast created and hosted by Jared Blumenfeld, https://www.podshipearth.com/firemyths.
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