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:

1. Does grazing reduce the likelihood of fires at the landscape scale?
2. Does fire severity differ between grazed and ungrazed lands?
3. What are the synergies and tradeoffs of grazing management as a tool to directly reduce wildfire risk?

Our results will be used to:

1. Suggest to individual land owners the potential for grazing to reduce their risk of wildfire
2. Influence policy makers to reduce barriers to grazing in California.

Our ecosystems evolved with fire and a short fire return interval in many ecosystems maintained a more fire safe habitat. Management of California rangelands have evolved over the years. Between 1853 and 1905, burning together with overgrazing and undesirable forest practices resulted in less dense woody vegetation and more successional vegetation dominated by annual grass (Heady, 1972). This led to a conservation movement of the early 1900s with an abrupt policy change on burning (Stephens et. al, 2007) including effective legislation against pervasive burning; however, according to Heady (1972), overgrazing probably had more influence on the grassland than over burning. And one of the greatest effects of the “excessive overgrazing pressure” was a reduction of the fine fuels that had previously carried wildfires (Miller et al., 1994).

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).

Manipulating management can help mitigate these climate driven trends (Starrs et al, 2018).Livestock grazing has been removed from many rangelands due to concerns that grazing negatively impacts plant communities. Historically, however, grazing pressure was one of greatest tools for reducing fine fuels that carry wildfires (Miller et al., 1994). There is a growing concern about the negative impacts of wildfires on rangelands, forest and communities across California, which has seen increasingly larger and more severe wildfires. These trends are predicted to continue (Yoon et al 2015). Livestock can play a role in reducing wildfire risk by removing fine fuels; the removal of livestock grazing can result in increased buildup of dead herbaceous biomass and potential conversion to shrub species such as coyote brush and Himalayan blackberry. Grazing treatments decrease fine fuel biomass, cover and height and increase fuel moisture, thereby decreasing ignition and initial spread of fire compared with ungrazed areas (Davies, et al., 2017). Livestock grazing can reduce the standing crop of perennial and annual grasses to levels that reduce fuel loads, fire ignition potential and spread; thus reducing the continuity of fuels including the amount of herbaceous biomass between woody species (Strand et al., 2014). Yet, while such data suggest that grazing may reduce fire severity and size, there is little research into the effects of grazing on fire at the landscape scale.

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

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/.                                                                                               

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. 

Any social program or economic structure that incentivizes grazing therefore indirectly incentivizes the most effective fire management tool available for use on rangelands.  A conservation easement is one such economic structure.  A conservation easement is an agreement between a landowner and a land conservation group, such as the Sonoma County Agriculture Preservation & Open Space District, Sonoma Land Trust, Marin Agriculture Land Trust or the California Rangeland Trust.    Under a conservation easement agreement the landowner receives a lump sum payment from the conservation group in return for accepting legally-binding prohibitions on further development of the land.  In addition to the lump sum payment, landowners often receive a reduction in their annual property tax liability.  Conservation groups, as well the community in general, receive benefits ranging from views of open space to preservation of wildlife habitat.  If the easement is “an affirmative agricultural easement” and on rangelands, it will most likely be grazed.  An affirmative agricultural easement is a voluntary legal agreement that restricts the use of land only to agriculture.   Affirmative agricultural easements are one of several different legal tools to help ranchers balance goals of: 1) generating revenue for ranching or retirement; 2) making their land more affordable to future ranchers; 3) keeping their rangelands “working”; and 4) maintaining a treasured legacy of sustainable working landscape stewardship.

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.

Also, where land trusts can improve landowner welfare, and landowners can select the payment structure that best aligns with their preferences.  Tailoring payment structures to individual landowners, conservation groups may be able to stretch their conservation dollar further, improving the welfare of the taxpayers or donors that support the group.  Additionally, building trust between landowners and conservation groups has the potential to improve welfare for both. UCCE is exploring alternative payment structures for conservation easements, in addition to lump sums.

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.

 

On a global scale, rangelands are a fairly diverse array of biomes - deserts, scrub, prairies, and chaparral, but in Sonoma County, they comprise oak savannahs and grasslands; one such is our vernal pools. Vernal pools are defined by the US Environmental Protection Agency as “…seasonal depression wetlands that occur under the Mediterranean climate conditions”. They are a rare and interesting sight to see in the spring after they have filled up with water. Especially this year, you could see the most beautiful concentric rings of various wildflower species as the water evaporates or infiltrates into the ground.

Vernal pools exist in areas of a grassland where there is an isolated area of compacted clay or bedrock. This is because the water cannot penetrate it and therefore, stays on the surface instead of absorbing into the soil. Depending on their size and amount of rainfall, they may fill and dry up many times within a season, or may not fill at all in a drought. Many species of wildlife, including birds and amphibians, depend on these pools. They are a cache of fresh water and food and, for some, a good place to lay their eggs because they are safe from predation by fish. 

For the first time in four years, US Fish and Wildlife Service (FWS) opened grazing permits for several properties in the Santa Rosa plains, allowing grazing. Grazing was returned to these properties because its removal caused vegetation to over grow, reducing habitat for the endangered species present. Not having this grazing “disturbance” resulted in a species loss; the very species that were to be protected. Two examples of grazing benefits are listed below. 

Fig 1 California tiger salamander (Ambystoma californiense), CaliforniaHerps.com

Fig 2 Sonoma Spineflower (Chorizanthe valida), UC Berkeley

Fig 3. Contra Costa goldfields (Lasthenia conjugans), UC Berkeley

Fig 4. Santa Cruz tarplant (Holocarpha macradenia), UC Berkeley

California Tiger Salamander

Managed livestock grazing is thought to benefit the habitat for California tiger salamander (Ambystoma californiense) (Fig 1). Some Bay Area populations of these salamanders depend on ground squirrel burrows for refuge sites. Livestock grazing keeps vegetation low, making the grasslands more suitable for California ground squirrels (USFWS 2003). Salamanders that inhabit vernal pools may also benefit from grazing. These ephemeral pools are wet only during the winter/spring rainy season, and too much vegetation in and around their edges can cause drying pools to lose depth too quickly. Because it reduces this vegetation, grazing can keep the pools wet longer, giving salamander larvae more time to grow up (USFWS 2004).

Opportunities for Native Plants

Grazing of non-native vegetation is essential to create opportunities for many native grassland plants. For example, there is only a single remaining natural population of the federally-endangered Sonoma spineflower (Chorizanthe valida) (Fig 2) and it declined dramatically after livestock was removed from its habitat area (Davis and Sherman 1992). Similarly, populations of the federally-endangered Contra Costa goldfields (Lasthenia conjugans) and Santa Cruz tarplant (Holocarpha macradenia) plummeted and died out when grazing was removed from their habitats (USFWS 2005; Hayes 1998).

Nowadays, 90% of the US's vernal pools have disappeared due to human encroachment and land conversion. Like the rangelands they exist on, they can be beautiful and vital places if properly managed! With the arrival of the Spanish missionaries, Sonoma County's grasslands changed dramatically. They became dominated by non-native annual plants, mostly from the grasslands of the Mediterranean Basin. Despite the general replacement of native plants by these non-natives, enough native species have survived to prompt global recognition of our grasslands as hot spots of biodiversity.

Because livestock grazing (primarily by cattle) can effectively reduce the biomass, height, and thatch accumulation produced by non-native annual plants, it has become an essential tool for managing our local grasslands. Grazing has been shown to be a benefit by 

reducing the risk of a catastrophic wildfire, maintaining and enhancing habitat for many native grassland plants and animals,

and maintaining the open character of our iconic grasslands and oak savannas.

Ranchers should be encouraged to continue their sustainable livestock production practices and their long history of good stewardship. In addition, they should be compensated for implementing other conservation services on rangelands.