A Review of Prescribed Fire for Forage Improvement and Fuels Management
Josh Harjes
Rangelands comprise 62 percent of California’s over one hundred million acre land area. The conversation around prescribed fire and fuel reduction work often focuses on forests (the only private land category on the California Wildfire and Landscape Resilience Interagency Treatment Dashboard is timber company land), but it is important to also emphasize the importance of this work in our rangeland ecosystems. Prescribed fire in rangelands not only protects the ranchers who work those lands and their communities, it is also beneficial for grassland ecosystems and grazing forage quality. Building awareness and incentives for a practice of combined grazing and burning holds the potential for both profitable ranching operations and meaningful progress in statewide wildfire resilience. As the 2023-2024 Grizzly Corps Fellow for the Wildfire Resilience Program at CAFF, I have gotten the chance to engage in conversations about prescribed fire and grazing management through workshops, research, and working groups. This is a collection of some of the things I have learned.
T.S. Gilde Horse Ranch, Community Alliance with Family Farmers HQ office, Davis, CA. Personal photo
When land stewardship and agricultural production overlap, it is always complex. However, learning from ranchers' experiences, indigenous knowledge, and ecological research, it is clear that land management practices exist in which agricultural production and sustainable land stewardship can coexist. California rangelands present an important opportunity to restore grassland health, increase the viability of ranching operations, and store stable carbon, all at the same time.
Grasslands Are a Globally Valuable Resource
A recent discussion paper from a consortium of conservation groups, including The Nature Conservancy, states that grasslands provide “crucial ecological habitats and food and income for over 1 billion people”, “stor[e] over 30% of the world's carbon stocks”, and make “substantial contributions to freshwater regulation [and] soil preservation”. Clearly, sustaining grassland health is essential not only to nature and the environment, but to agricultural production as well.
Grazing has been used to manage California grasslands for millennia. Tending the Wild, by M. Kat Anderson, speaks volumes to the importance of Indigenous land management of these ecosystems. California grasslands evolved with frequent disturbances from grazing animals and fire, both of which stimulate growth and prevent tree and shrub encroachment. Today, it’s cattle that are grazing the land instead of elk and pronghorn, and grasslands experience fire far less often than they used to. While grasslands are a natural and long standing feature of the California environment, they are a disturbance dependent ecosystem. Grasses grow faster than woody species like shrubs and trees, but they are less hardy and long-lived. Grasslands will be overtaken by forests unless the ecosystem experiences recurring disturbances that disrupt the woody species growth. When forests overtake a grassland or meadow, it is called conifer encroachment (Forest Service paper on conifer encroachment in CA). The grasslands that have existed in California for thousands of years were sustained and invigorated thanks to Native Californians’ use of recurring, and variable disturbances.
In California, native grasslands are dominated by perennial bunchgrasses. These bunchgrasses provide greater soil water retention and carbon sequestration than do non-native grasslands, which are typically dominated by annual grasses. The roots of perennial grasses extended between six and nine feet down into the ground whereas the roots of annuals extend only about a foot. The annual grasses die each year and regrow their entire plant structure from seed. This requires more water than perennial grasses, which retain their root structure year after year. The deeper root structure of perennial grasses improves water infiltration, provides greater soil stability, and sequesters more carbon than annual grasses. This is because each summer when the above ground leaves of grasses die off, a proportionate amount of the root structure is also abandoned. Root sloughing deposits carbon directly into the soil during every dry season.
While trees can store a lot of carbon, they do this primarily by growing taller. This adds more and more fuel to the above-ground landscape, and when it burns, will release that carbon back into the atmosphere. A native California grassland sequesters that carbon into the soil. Perennial grasses are also more resistant to destructive wildfire than annual grasses. They often grow in bunches and stay green further into the summer than do annuals. From a wildland fire behavior perspective, this means that fuels will be less continuous, and fuel moisture will be greater. Both of these characteristics reduce the danger of rapid wildfire spread. To read more about wildland fire behavior, check out the Fire Behavior Triangle on NPS.gov.
Patchy Fire Improves Forage Quality
Left untouched, grasses grow densely, producing thick layers of thatch (dry plant material) that cover the soil and make it difficult for new grass seeds to grow and for rainfall to penetrate to the soil. Grassland ecosystems are most bioproductive under some amount of disturbance. Grazing is a disturbance to the grassland ecosystem that, when managed correctly, stimulates new growth and helps cycle nutrients. After fire passes through, similar processes are underway. The ash and biochar created from burning facilitates the cycling of nutrients back into the soil. Grasses get access to more sunlight in the opened grassland.
A patchy mosaic effect in a grassland burn in Sonoma County. Personal photo
Research providing evidence for grazing animals’ preference towards recently burned grassland patches is well-established. (Allred, 2011) But can the fire-grazing interaction be strong enough to actually drive those fire regimes in the environment, not just be affected by them? “Ungulate preference for burned patches reveals strength of fire–grazing interaction”, a paper on research conducted in Oklahoma, set out to test this. They found a strong grazing preference for recently burned patches in both bison and cattle. Over the course of four years, the researchers burned the whole unit, one quarter each year. The animals’ were allowed access to the entire unit, and their movements were monitored. For bison, it was actually the strongest determinant of where the animals would graze, greater than proximity to water, shade, or slope. Cattle showed the strongest preference for grazing in proximity to shaded areas, but preference for recently burned patches was a close second. Forage quality, measured by crude protein levels of the vegetation in the patches, was highest (double than that of other areas) in the most recently burned areas. Forage quantity increased as the time since burn increased creating a tradeoff relationship between forage quality and quantity.
Crude protein levels are highest right after a burn. (Allred, 2011)
Fire has a strong influence on animal behavior. The fire-grazing interaction “shapes the system, creates heterogeneity, influences ecosystem processes, and determines plant and animal populations and distributions.”(Allred, 2011) Utilizing this relationship is an important land management practice for ecosystem health, and the Allred study shows that it is also compatible with animal grazing behavior. Burning in small patches creates better forage quality, which the cattle then seek out. Once this dynamic is established, the cycle self-reinforces; recently burned patches that are then grazed will be unlikely to burn again when a nearby patch is ignited. It is important to consider the return interval of both fire and grazing with respect to weather, seasonality, erosion, water quality and food safety concerns. A well managed grassland thrives when the disturbance from both fire and grazing is frequent enough that woody species and thatch are minimized, but with enough time in between for grasses to rest, recover, and regenerate. Rotational treatments with high impact and low duration are key. A rotational treatment regime achieves necessary disturbance, invasive or noxious plant management, allows the grassland to thrive, and builds a resilient ecosystem structure that can better withstand both drought and wildfire.
Grazing and Grassland Stewardship
Sheep grazing under a Valley Oak tree in Mendocino County. Personal photo
Targeted grazing is a practice used to achieve specific land management goals like fuels reduction, or invasive plant control. By employing targeted grazing techniques, cattle ranching operations can offer ecological benefits to the land. While initial costs may be higher, sustainable beef commands a premium price compared to conventional products, and effective land management reduces expenses related to water and erosion control. Open-range grazing involves cattle roaming freely over large areas, while targeted grazing directs them to specific areas to manage vegetation and reduce fire risks. This approach enhances biodiversity by promoting native plant growth, which supports pollinators and other wildlife crucial to ecosystem health. Ecologically, targeted grazing improves soil fertility through natural fertilization, reduces invasive plant species, and mitigates wildfire risks by creating firebreaks. These practices enhance water retention in soils, fostering resilient landscapes that withstand drought and erosion, thus lowering long-term management costs. Check out this research summary from the Journal of Rangeland Ecology and Management to learn more about targeted grazing. Targeted grazing fosters healthier ecosystems by promoting biodiversity, enhancing soil health, and mitigating environmental risks. These benefits demonstrate the potential for cattle ranching to align with ecological stewardship.
Cows grazing at Pepperwood Preserve. Personal photo
Pepperwood Preserve is a great example of what is possible when prescribed grazing and burning are carefully combined. This organization stewards just over three thousand acres of land in the Mayacamas mountains near Santa Rosa, California. Situated in the interior Coastal Range, it experiences a temperate coastal climate typical of the area. Within the preserve are conifer forests, oak woodlands, and nine hundred acres of grassland. This spring, I got the chance to see and learn about Pepperwood’s conservation grazing program firsthand at a workshop called “Stewarding our Native Grasslands”. The Preserve uses a herd of Belted Galloways that are moved between paddocks 20 to 40 acres in size from October to May. The cattle belong to Markegard Family Grass Fed, a sustainable beef cattle operation based out of Half-Moon Bay. Conservation grazing using cattle has been employed at Pepperwood since 2013. Cattle were chosen over goats or sheep for the conservation grazing program at Pepperwood because they can eat more–the preserve has an extensive grassland to manage. Goats tend to prefer the leaves of hardier, woody species over grasses and are better suited for fuels management in shrub ecosystems. An added benefit of cattle is that they facilitate the recycling of dead and dried grasses. Beneficial hoof activity is when cattle and other grazing animals recycle the dead and dried grasses by pushing the material back into the soil. In addition to recycling biomass, beneficial hoof activity increases the water retention of the grassland. (Read more about beneficial hoof activity on Beef Magazine) Little divots are created in the soil, which catch puddles of water when it rains. Sometimes it is better to use smaller animals like goats or sheep if there is a concern for sensitive habitat or erosive soil types. Different livestock also move differently across various topographies. (National Forage and Grasslands Curriculum, Oregon State University) Sheep and goats, by virtue of being lighter animals, will physically impact the landscape less than cattle. It is important to consider the physical effects your grazing animals will have on the land.
The complex interplay between land stewardship, cattle grazing, and ecosystem health in California rangelands presents both challenges and opportunities. Droughts and heat waves exacerbate wildfire behavior, and are also threatening the health of our grasslands. However, farmers and ranchers are uniquely positioned to be at the forefront of management for wildfire resilience in their communities. With deeply rooted local knowledge of the land and its ecology, and the knowhow required for operating heavy equipment, there is potential for climate resilience work to be done across agricultural communities in California. Cattle ranching is often portrayed as environmentally detrimental, but the reality is far more nuanced. Sustainable practices, rooted in traditional ecological knowledge and supported by ongoing research, demonstrate that agricultural production and land stewardship can coexist. By implementing strategies such as prescribed fire, ranchers can not only sustainably manage their lands but also enhance grassland health and increase resilience against wildfires. Through careful management of cattle, conservation grazing shows improvements in forage quality and nutrient cycling, highlighting the effectiveness of grazing as a land management tool.
A Yolo PBA burn in Capay, CA. Photo credit, Yolo PBA.
Partnerships between ranchers and Prescribed Burn Associations (PBAs are community organizations that gather volunteers, gear, and expertise to help their neighbors implement beneficial fire) are popping up across California. Last June, the Yolo PBA held its inaugural burn on a private ranchland near Capay. The objective of the burn was to remove barbed goatgrass and other invasive species. The burn was completed safely, and post-fire site monitoring continues for evaluation of the treatment effectiveness. These partnerships are invaluable for exchanging information and training, and for providing ranchers with the personnel to implement burns.
Pilz Produce, a recipient of CAFF’s Fire Foundation Grant, after a mechanical fuels reduction treatment on a steep slope. Goat grazing will maintain the fuel load from here on out. Personal photo
Sustainable practices for ranching operations must be incentivized and supported through grant funding and education. The Community Alliance with Family Farmers recently completed a pilot project which provided funds from the California Fire Foundation to farmers and land managers in Placer County for small scale fuels management projects. Furthermore, permitting pathways to the implementation of prescribed fire must be streamlined, and liability funds expanded. There is a disconnect between land management for production and for conservation. While many good reasons exist for that rift to have occurred, California has arrived at an all-hands-on-deck situation for increasing resilience to drought and wildfire. By prioritizing land stewardship alongside agricultural production, California rangelands can serve as models of ecological resilience, benefiting both rural communities and the environment.
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