- Author: Stephanie Larson
UCCE Sonoma County along with other UC colleagues, recently received a grant to identify the impact of grazing on the frequency and severity of wildfire in California. The project will ask three specific questions:
- Does grazing reduce the likelihood of fires at the landscape scale?
- Does fire severity differ between grazed and ungrazed lands?
- What are the synergies and tradeoffs of grazing management as a tool to directly reduce wildfire risk?
Our results will be used to:
- Suggest to individual land owners the potential for grazing to reduce their risk of wildfire
- Influence policy makers to reduce barriers to grazing in California.
With the reduced frequency of wildfires, woody plant cover increased and shrublands and woodlands expanded (Miller et al., 1994). Burning was reintroduced around 1945, with the primary purpose to convert bushlands to grassland and to maintain the rangelands brush-free. An average of 67,000 acres of brush was burned annually under State permit from 1945 to 1951; and from 1951 through 1952, 133,000 acres burn annually (Biswell, 1954). With environmental conservation movement in the 1960s and 70s, controlled burning again was not favored and fire suppression was the referred management tool. This allowed ecosystems to accumulate more fuels that are prone to burning on a regular interval. Management practices can greatly affect a landscape's fuel amount and distribution. Fuel load, or biomass, is one of the most influential and easily manipulated fuel variation affective fire intensity (Strand et al., 2014). Livestock grazing is one management technique that has been shown to decrease fine fuel loading and subsequent wildfire severity (Davies et al., 2010).
Fire fuel treatments are designed to alter fuel conditions so that wildfire is easier to control and less destructive (Reinhardt et al., 2008). Cattle grazing primarily alters fuel conditions by reducing the amount of herbaceous fine fuels, whereas goat and sheep grazing can potentially also reduce the shrub component. Other fuel treatments that can be used to accomplish these same objectives include herbicides, mechanical treatments such as mowing, prescribed/controlled fires, or a combination of these treatments (Nader et al., 2007). Many studies have reviewed and describe factors affecting fuel treatment costs but studies specifically on rangelands are limited. Least cost fuel treatments will vary with conditions and objectives, but grazing alternatives appear to be cost-competitive especially if the objective is reduce fire fuel loads where mowing or a prescribed burn are potential alternatives (Strand et al., 2014).
Over the years, management has played a significant role in shaping California's rangelands. On a yearly basis, grazing can reduce the amount and alter the continuity of fine fuels, potentially changing wildfire fire spread and intensity (Stand et al., 2018). With changing climate conditions, it is now more critical than ever that grazing, as a fire fuel reduction tool, be scientifically quantified in order to demonstrate its use to landowners, managers and policy makers. California provides a unique opportunity to analyze how grazing effects wildfire trends due to the presences of long-term fire and climate datasets as well as diverse conditions under which grazing takes place. California is likely to see an increasing number of extreme fire danger days, almost doubling from current numbers over the next 50 years (Yoon et al, 2015).
The research project will use data from the past 30 years of wildfires across the whole state of California, along with data on climate, vegetation type, land ownership and biophysical variables to determine if grazed areas burned less frequently and/or with less severity than non-grazed areas. In addition, we will seek to identify trade-offs and synergies between grazing wildfire management. In areas where there is a high probability of ignition and the area is grazed, is there an optimum residual dry matter (RDM) to be managed for to reduce risk? Are there barriers to reaching the optimum RDM levels? Grazing by livestock is likely the most cost effective and practical treatment to apply across large landscapes scales to manage herbaceous fuels (Davies et al., 2015). Grazing can alter fuel characteristics of an ecosystem; however, little is known about the influence of grazing on fire, in particular ignition and initial spread and how it varies by grazing management differences (Davies, et al., 2017).
This project promotes the scientific significance andstrength of the UC network through collaboration of advisors and specialist to benefit California beef cattle producers and the rangelands they graze. It will address the priority of managing rangelands for multiple ecosystem services especially documenting the “why should we” and when to graze working landscapes to reduce fire severity in California. The research project will lead to more informed lands landowners, managers, policy makers and public on the importance of managing rangelands, through grazing. Research results will address the following issues:
Reducing Wildfire Risk. Increasingly severe wildfires are impacting an array of communities, including many lower income areas such as Lake and Mariposa Counties.
Wildfires increase air pollutants such as PM, CO and O3, amplifying problems that are already more severe in less affluent, inland areas. Wildfires put firefighter's lives at risk, reduce state funds available for other needs, jeopardize infrastructure, and increase insurance and utility costs. Improved wildland management for fire has already become a critical issue, with important implications for Low-Income Communities.
Sustaining Water Supply. Concerns were raised about the water supply that serves many counties during recent years up and down the state. East Bay Municipal Utility District rerouted staff from projects on district owned land in the Mokelumne watershed to burned areas above their reservoirs to help revegetate the watershed, and decrease erosion into Pardee Reservoir, drink water supply for the East Bay. Fires in Sonoma County about Lake Sonoma could have impacted the water source for both Sonoma and Marin County residence. In addition, the severity of wild fires in Santa Barbara and Ventura caused mud slides which lead to reductions in water quality and reservoir capacity. Improved wildland management will become increasingly important for maintaining California's water supply.
Maintaining Tourism Economy. Many of the state's rural areas, especially in the Sonoma, Santa Barbara, and Ventura depend heavily on tourism for local economies. The occurrence of fires impacted the number of tourist visiting, along with the commodities grown in those counties, i.e. grapes, vegetables, etc. The 2018 Ferguson Fire closed Yosemite National Park for an unprecedented two weeks, a large impact for a heavily touristy area around Yosemite and central California Foothill communities. Improved wildland management is becoming an important issue for maintaining tourism economies across rural California.
Increasing Grazing Lands. Many state lands are not currently managed to control fine fuels. Using livestock to manage them will open opportunities for more grazing lands, potentially allowing for greater flexibility of managing herds already in the state and providing opportunities for newer ranchers. In addition, controlling brush and reseeding an area has been documented to provide up to 2,000 lbs./acre in additional forage (Biswell, 1954), providing not only access to more forage for livestock, but also decreasing brush as a fuel. Both the coast range foothills and the Sierra Foothills can benefit from reduced brush encroachment.
Citations upon Request
- Author: Stephanie Larson
- Editor: J. M.
Prescriptive Grazing as a Vegetation Management Tool
Stephanie Larson & John Gorman
Working landscape ecosystems provide benefits to the landowner and to all life forms living or passing through that land. Neighbors benefit with open viewscapes, to clean water and air, and carbon sequestration from well-maintained working landscapes – rangelands, grassland, and open space. There also a potential health benefits received from working landscape from properly managed vegetation removal to reduce the fire fuel loads. However, there are many challenges for landowners to control excessive vegetation on working landscapes, including vast roadless areas that limit access for weed control and lands of low economic value that make chemical and mechanical control impractical. These challenges favor biological control methods; such as insects and microbes for biocontrol, which can be effective but are difficult, expensive, and time consuming to develop. There is, however a readily available and under-exploited tool that has gained interest to manage vegetation – livestock grazing. Along with prescribed fire, grazing of domestic livestock may be the earliest vegetation management tool employed by humans. We suggest that the challenges of vegetation management on working landscapes may be addressed with the careful sharpening of this old tool. Prescription grazing is the application of livestock grazing at a specified season, duration and intensity to accomplish specific vegetation management goals. Controlled grazing of this type is being employed throughout California on public and private land and is proving to be a promising tool in reducing the fire fuels and unwanted, excessive vegetation. Furthermore, livestock grazing has one distinct advantage over other control methods; in the process of controlling an undesirable plant, grazing animals convert it into a saleable product.
Steps in Developing a Grazing Prescription
Formulating an effective grazing prescription requires a solid understanding of plant ecology, animal behavior, and plant-animal interactions. A grazing prescription should include specific information on the season and intensity of defoliation, the species, breed, sex, and age class of animal to use, and the stocking rate that will result in the most harm to the target plant and still maintain healthy rangeland ecosystems. A successful grazing prescription should: 1) cause significant damage to the target plant; 2) limit irreparable damage to the surrounding vegetation; 3) be consistent with livestock production goals; and, 4) be integrated with other control methods as part of an overall weed management strategy.
Selecting the Right Species
The species of livestock best suited for the specific vegetation management goals depends on both the plant species of concern and the production setting. Cattle have large rumens that are well adapted to ferment fibrous material and are classified as grass and roughage eaters. They are therefore generally superior to goats or sheep to manage fibrous herbaceous vegetation such as dormant grasses. Goats have narrow and strong mouths well designed for stripping individual leaves from woody stems and for chewing branches. Goats also have a large liver mass relative to cattle or sheep and may therefore more efficiently process plants that contain secondary compounds such as tannins or terpenes. Sheep are generally considered an excellent species to accomplish control of herbaceous weeds. Sheep possess a narrow muzzle and a relatively large rumen per unit body mass. These characteristics allow them to selectively graze and yet tolerate substantial fiber content, and results in diets generally dominated by forbs. Sheep are also small, sure-footed, and well suited for travel in rough topography which may not be easily accessible for chemical weed control.
Grazing Workshops for Working Landscapes in Sonoma & Marin Counties
Creating resiliency in the rural landscape of Sonoma and Marin Counties is critical in preparing for the next natural disaster, managing biodiversity or achieving ecosystem service goals such as carbon sequestration, wildlife habitat and viewsheds. This growing recognition of the ecological benefits livestock grazing is important to our County's resiliency. However, grazing can be difficult to landowners that have never grazed their properties before. UC Cooperative Extension will hold several workshops on prescriptive grazing techniques to address the sustainability of our working landscapes while reducing the vegetation that leads to catastrophic wild fires. Private land owners manage the majority of the open spaces in Sonoma and Marin Counties and these workshops are aimed at those private citizens and other public land owners that are interested in using grazing as a vegetation management tool. Increasing the number of agriculture land grazed will benefit both public and private open space and the residents that benefit from them. The goal of the workshops is to increase understanding, interest and acceptance of using grazing as a vegetation management tool. Workshop series include:
Series 1-Understanding the use and benefits of grazing:
- examples of properly managed grazing sites stopping and slowing wildfires
- Education on positive effects of grazing on ecology including plant and animal biodiversity
- Benefits of livestock on local community and resiliency
Series 2- Site assessments of properties interested in implementing a grazing program:
- Identifying feasible sites on property
- Site plans and proper fencing (permanent/electric/ mobile)
- Animal husbandry
- Choosing the right animals for you and your property (sheep, goats, cattle)
Series 3- Livestock Economics – assessing sustainability and profitability from grazing livestock:
- Potential marketing of livestock products and associated costs of care and processing
- Infrastructure costs and value added from grazed lands
- Leasing options – how to find the right grazer
- Applying for cost share programs – NRCS, RCD, CalFire
Sonoma and Marin County's working landscapes, properly managed with prescription grazing, could prove to be a winning solution for all parties involved. Grazing not only provides a service to land owners and managers that may not be easily achieved in other ways, but it can also provide an income stream to aspiring livestock grazers just starting their grazing businesses. These workshops will provide educational opportunities for all parties to learn the “how to” in grazing, landowners who what to graze themselves, landowners who want to hire grazes and grazers who are looking to start or increase their grazing business enterprise. Let's work together to sharpen the “old” tool of “livestock grazing” into the “new vegetation management tool” for working landscapes. For more information on grazing workshop dates and locations: http://cesonoma.ucanr.edu/Livestock_and_Range_Management/.
- Author: Stephanie Larson
- Author: Reid Johnsen
- Editor: J. M.
Eight months after devastating fires swept through Sonoma County, our community has rallied to an ongoing recovery. Still, the tragedy of those wildfires remains fresh in the minds of our friends and neighbors. The lives and property that were lost last year can never be replaced. As the dry season begins a new and unfortunate truth comes to mind: California is a drought-prone state, and there will always be some risk of wildfire. In Sonoma and Marin Counties, active rangeland management is one of the most important actions that can be taken to reduce the risk of wildfire to our community.
Sonoma and Marin Counties comprise large amounts of rangeland. The key to reducing fire risk on rangeland parcels is effective management of the volume of flammable grasses, known as Residual Dry Matter (RDM), which exists on the land during the summer months. Historically, three methods have been employed to manage RDM: mowing, controlled burning, and grazing. However, mowing is rarely cost-effective at the landscape scale, and concerns over air pollution have significantly restricted the viability of controlled burning as a management technique. Grazing is the best remaining tool for RDM management, and it provides the additional social benefit of producing agricultural income.
There is only one affirmative agricultural easement in Sonoma County, Marin County has many more. Many conservation easements in Sonoma and Marin Counties have been managed by the same families for multiple generations, many have changed ownership with the easement attached. One of the primary advantages of conservation easements is that they typically allow existing agricultural practices to continue on the conserved parcel; however the economics of agriculture change over time. It might be more advantageous to sustain local agriculture, reduce fire risks, and keep our working landscapes “working” if conservation groups reassessed conversation easements written years ago. Climate change, ranching and farming economics and agricultural practices have changed and keep evolving. Agricultural operations that remain economically viable will keep our cultural heritage for generations to come.
Traditionally, when a landowner sells a conservation easement to a conservation group, the landowner receives a one-time lump sum payment in exchange for accepting permanent development restrictions on their land. It may be possible for a land trusts to manage its finances for greater returns or less risk relative to the options available to landowners.
The University of California Cooperative Extension (UCCE) is finalizing a research project that has examined that equivalent, alternative payment structures, such as a perpetuity or variable annual payment, could provide greater welfare to both the landowner and the conservation group. Our preliminary research findings shows that many landowners state a preference for an alternative payment structure, and that heterogeneity in those preferences is correlated with self-identification as a rancher/farmer.
In order to evaluate changing perceptions of conservation easements over time, UC Cooperative Extension of Sonoma County, is conducting a phone survey of landowners in Sonoma and Marin Counties. This brief survey is aimed at all owners of parcels greater than 50 acres that currently support livestock or have the potential to support livestock. Full participation in the survey will help UC Cooperative Extension better meet the needs of the agricultural communities in Sonoma and Marin Counties. If you receive a call, your participation will be greatly appreciated. It's your opportunity to help us direct the future of conservation easements in Sonoma and Marin Counties.
- Author: Stephanie Larson
- Author: Adam Livingston
- From: California Economic Summit
To accelerate California's policy leadership in the face of global crises like water scarcity, climate change and uneven economic development between urban and rural areas, it is essential to recognize of the importance of the state's natural capital, especially in relation to working landscapes and rural economies. The California Economic Summit defines working landscapes to include farmland, ranches, forest, wetlands, mines, water bodies and other natural resource lands, both private and public. Carbon is the energy currency of most biological systems, including agricultural ecosystems. All agricultural production originates from the process of plant photosynthesis, which uses sunshine to combine carbon dioxide (CO2) from the air with water and minerals from the soil to produce plant material, both above and below ground.
Agriculture is the ONE sector that can transform from a net emitter of CO2 to a net sequestered of CO2.
There is no other human-managed realm with this potential. Common agricultural practices, including driving a tractor, tilling the soil, grazing, result in the return of CO2 to the air. However, all farming is “carbon farming” because all agricultural production depends upon plant photosynthesis to move carbon dioxide out of the atmosphere and into the plant, where it is transformed into agricultural products, whether food, flora, fuel or fiber. Agriculture contributes only 9 percent of the carbon dioxide emissions in the US (EPA); and agricultural landscapes, particularly grassland/rangelands, have great potential to function as a sponge for carbon dioxide from our atmosphere. The maximum capacity of soil to store organic carbon is determined by soil type (percent clay); management practices implemented to maximize plant growth and minimize losses of organic carbon from soil can increase organic carbon storage in soil. Keeping working lands “working” can result in long-term carbon storage (decades to centuries or more) in soils.
There is a growing body of work suggesting that significant amounts of carbon can be stored in soil. This is particularly true on rangelands, which house approximately 30 percent of terrestrial carbon stocks in addition to a substantial amount of aboveground carbon in trees, plants and grasses, and can hold carbon over longer periods of time (FAO, 2009; Flynn, A., et al., 2009; White, R., et al., 2000). Management of rangelands, through grazing, can lead to increased forage production, longer growing seasons and a potential conversion to a perennial system. Grazing stimulates plant growth through a variety of mechanisms, resulting in increased carbon capture by the grazed ecosystem. The potential to increase the amount of carbon held in rangeland ecosystems or to minimize losses of existing carbon offer landowners an opportunity to manage their lands in ways that contribute to climate change mitigation by encouraging carbon sequestration. This can be done by increasing carbon inputs and uptake, decreasing or preventing carbon releases, or both. Given that there are 57 million acres of rangeland in California alone, and that rangeland is the largest land type on our planet today, these practices can make a significant contribution to carbon sequestration.
How to increase carbon stored:
An approach known as “Carbon Farming” involves implementing practices that are known to improve the rate at which CO2 is removed from the atmosphere and converted to plant material and/or soil organic matter. Carbon farming is successful when carbon gains resulting from enhanced land management and/or conservation practices exceed carbon losses. These practices increase the amount of photosynthetically captured carbon held, or “sequestered”, in long-term carbon pools on the farm or ranch, including soil organic matter, perennial plant roots and standing woody biomass. This results in a direct reduction of carbon dioxide in the atmosphere.
Expanding Carbon Markets:
Expanding investment in programs that support carbon sequestration in soil, such as the Healthy Soils Program, can create stronger financial incentives for ranchers to implement these practices (De Gryze, S., et al., 2009). Moreover, given the well-established relationship between soil organic matter (of which an average of 50 - 56 percent is carbon) and the ability of soils to retain water (Huntington, 2007; Pribyl, 2010; Rawls et al., 2003), such a market could contribute to watershed function, natural groundwater recharge and overall water provision. The scientific consensus surrounding the relation between greenhouse gas (GHG) emissions and global climate change has indicated a clear need for the U.S. to find new ways to reduce emissions of these gases and the concentrations in the atmosphere to avoid significant and potentially catastrophic environmental changes. Land management for carbon sequestration is one of many opportunities available to the U.S., more locally in California, to reduce their net emissions of GHGs, particularly CO2. Carbon-oriented management of working landscapes may offer landowners the opportunity to obtain a new source of income while simultaneously helping to mitigate climate change. The payment for ecosystem services, such as carbon sequestration, may be a potential solution to climate change. The value of California's natural capital will be an important part of the conversations at the 2017 California Economic Summit taking place in San Diego on November. Solutions like improving the state's ecosystem services management represent ways to boost California's triple bottom line: simultaneous growth in the economy, improvement in environmental quality, and increased opportunity.
Stephanie Larson is director of University of California Cooperative Extension, Sonoma County; and Adam Livingston is director of planning and policy at the Sequoia Riverlands Trust
- Author: Stephanie Larson
Carbon is the energy currency of most biological systems, including agricultural ecosystems. All agricultural production originates from the process of plant photosynthesis, which uses sunshine to combine carbon dioxide (CO2) from the air with water and minerals from the soil to produce plant material, both above and below ground.
Agriculture is the ONE sector that can
transform from a net emitter of CO2
to a net sequestered of CO2
There is no other human-managed realm with this potential. Common agricultural practices, including driving a tractor, tilling the soil, grazing, result in the return of C02 to the air. However, all farming is “carbon farming” because all agricultural production depends upon plant photosynthesis to move carbon dioxide out of the atmosphere and into the plant, where it is transformed into agricultural projects, whether food, flora, fuel or fiber.
Agriculture only contributes 9% of the carbon dioxide emissions in the US.1 Agriculture, particularly grassland/rangelands, have a great potential to function as a sponge for carbon dioxide from our atmosphere. The maximum capacity of soil to store organic carbon is determined by soil type (% clay). However, management practices, implemented to maximize plant growth and minimize losses of organic carbon from soil, will result in greatest organic carbon storage in soil. Keeping working lands “working” can result in carbon stored long term (decades to centuries or more) beneficially in soils in a process called soil carbon sequestration; long-term carbon storage (decades to centuries or more) in soils.
Keeping working lands “working” can result in
carbon stored long term
Rangelands: There are 23 million hectares of rangeland in California alone, and it is the largest land type on our planet today. Management of rangelands, through grazing, can lead to increased forage production, longer growing season and a potential conversion to a perennial system. Implementation of practices can meet both ranch goals while increasing the carbon sequestration on rangelands. Grazing stimulates plant growth through a variety of mechanisms, resulting in increased carbon capture by the grazed ecosystem. The potential to increase the amount of carbon held in rangeland ecosystems or to minimize losses of existing carbon offer landowners an opportunity to manage their lands in ways that contribute to climate change mitigation by encouraging carbon sequestration. This can be done by increasing carbon inputs and uptake, decreasing or preventing carbon releases, or both.
How to increase carbon stored: A practice, known as “Carbon Farming” involves implementing practices that are known to improve the rate at which CO2 is removed from the atmosphere and converted to plant material and/or soil organic matter. Carbon farming is successful when carbon gains resulting from enhanced land management and/or conservation practices exceed carbon losses. Management practices that increase the amount of photosynthetically-captured carbon held, or “sequestered”, in long-term carbon pools on the farm or ranch, include soil organic matter, perennial plant roots and standing woody biomass. This results in a direct reduction in the amount of carbon dioxide in the atmosphere.
Loren Poncia, Stemple Creek Ranch, has implemented a carbon farming plan to not only sequester carbon but enhance the quality and quality of his forage. Loren owns a grass based beef operation, and his animals are born, raised and finished on grass. He needs to supply adequate nutrition for his cattle have proper growth to his meet market goals. As part of his carbon plan, Loren implemented a grazing management plan, to promote perennial grasses growth. Perennials have deeper root systems, and will store more carbon, deeper in the soil. Loren checks the quality of his forage using a spectrometer, measuring sugar levels in the grasses, (Figure 1).
Expanding Carbon Markets: There is a growing body of work suggesting that significant amounts of carbon can be stored in soil. This is particularly true on rangeland, which houses approximately 30 percent of terrestrial carbon stocks in addition to a substantial amount of aboveground carbon in trees, plants and grasses, and can hold carbon over longer periods of time.2 Expanding investment in programs, such as Carbon Farming and the Healthy Soils Program, can support agricultural practices that add to these stocks, creating potential markets to pay ranchers for sequestering carbon.3 Moreover, given the well-established relationship between soil organic matter (of which an average of 50 - 56% is carbon) and the ability of soils to retain water,4 such a market could contribute to watershed function, natural groundwater recharge and overall water provision.
The scientific consensus surrounding the relation between greenhouse gas (GHG) emissions and global climate change has indicated a clear need for the US to find new ways to reduce emissions of these gases and the concentrations in the atmosphere to avoid significant and potentially catastrophic environmental changes. Land management for carbon sequestration is one of many opportunities available to the US, more locally in California, to reduce their net emissions of GHGs, particularly CO2. Carbon-oriented management of rangelands may offer landowners the opportunity to obtain a new source of income while simultaneously helping to mitigate climate change. The payment for ecosystem services, such as carbon sequestration, may be a potential solution to climate change.
2 FAO, 2009; Flynn, A., et al., 2009; White, R., et al., 2000.
3 De Gryze, S., et al., 2009.
4 Huntington, 2007; Pribyl, 2010; Rawls et al., 2003.