ANR Green Blog
For millennia, fires periodically burned through California forests, thinning trees, reducing shrubbery and clearing out downed branches and debris. Without periodic fire, the forests became more dense, with spaces between large trees filling in with a thick carpet of duff, seedlings and shrubs.
As a result, today's forests are prone to more intense and damaging fires, like the Rim Fire, King Fire, and — most recently — the Camp Fire in Butte County. These fires are burning with unprecedented severity and speed, threatening large swaths of forest, towns, and even urban areas.
Using fire as part of forest management is not a new concept. Native Americans were known to burn brush to open up hunting grounds and clear shrubbery for gathering. Decades ago, iconic Berkeley forestry professor Harold Biswell said, “Fire in the Sierra Nevada is as important as rain.”
Competing forces, however, pushed foresters and fire officials toward fire prevention and suppression, particularly the cataclysmic fires of the early 20th century that leveled entire towns and left dozens of residents and firefighters dead. The fear of out-of-control blazes and the perceived damage to timber resources launched a war on fire that has lasted a hundred years. Some forest managers are urgently trying to negotiate a truce.
Making peace with fire and turning it into a useful tool, rather than a raging threat, was the objective of an October meeting in Shaver Lake of UC Cooperative Extension forestry and natural resources scientists, Southern California Edison forest managers, CALFIRE officials and U.S. Forest Service representatives.
The event also raised awareness of “pyrosilviculture,” a new forest management term coined by UC fire scientist Rob York to emphasize the importance of fire in silviculture, the management of forests for wood.
Forests have myriad benefits – recreational, environmental and economic. Nature lovers value the whisper of pine trees in the wind and green shade over hiking trails and ski slopes. Owls, bears, deer and other wildlife make their homes among firs, pines, oaks and cedars. Forests stabilize mountain slopes, which store water as snow for agriculture and drinking. People build their homes, businesses and schools out of the planks and boards cut from the straight, soft wood of conifer trees.
The value of California forest products was about $429 million in 2017, according to the USDA. Because fires can damage and destroy trees, the timber industry has historically been reluctant to use fire as a tool. That's changing.
“Fire is such an important ecological process, you can't manage for timber without fire,” York said.
York is the manager of the Blodgett Forest Research Station, UC Berkeley's 4,000-acre mixed conifer and oak forest near Georgetown where researchers study forest management practices for increasing timber yield while taking advantage of fire to enhance forest health and make forest stands more resilient to wildfire.
Controlled burning can be used to treat fuels and reverse these trends, but it has been inhibited by a number of barriers, including landowners' concerns about liability, risk aversion among fire management agencies, narrow burn windows, air quality limitations and other regulatory challenges. Now, public demand for prescribed fires is growing.
“I believe what moved the needle was, for several years in a row, there were high-severity fires in the news,” York said. “Wildfires were in the pubic zeitgeist. People began asking, ‘Why aren't we doing more prescribed fire?'”
Climate change is also intensifying the interest among the public and silviculture professionals. Because California is getting warmer and fire seasons are growing longer, high-severity fires are expected to increase.
“There would logically be a tipping point. Even though we reduce the growth of trees when we use fire, if it can prevent the loss of the forest entirely, it would be meeting the timber objective,” York said.
The vast tree die-off during the 2011-2016 drought was another jarring sign that the Sierra Nevada ecosystem is out of balance.
The U.S. Forest Service, which manages 20 million acres of forest in California, is using prescribed fire to reduce fire risk on federal forestlands, but scientists say it's not nearly enough to reduce the threat of catastrophic wildfire. CAL FIRE is ramping up its controlled burn efforts, but it will take time to address far-reaching areas of overgrown forestlands. The agency sometimes uses mechanical measures such as mastication and chaining before burning to pre-treat fuels and prepare units for burning.
“We need to work around communities first, and then move out to the wider landscape,” said CAL FIRE division chief Jim McDougald. “If a prescribed fire moves into a subdivision and burns houses, we take 100 steps back.”
“Burning is a key element of forestland management and it can be safe if done properly,” Kocher said. “We provide classroom instruction and invite participants to join a live prescribed fire at Blodgett Forest as part of their training so they become familiar with the process.”
At the training sessions, UC Cooperative Extension advisor Lenya Quinn-Davidson said that in some cases, private landowners can conduct burns themselves. In her hometown in Trinity County, many ranchers and landowners conduct small broadcast burns to reduce fuels and improve forage. These burns are typically quite small and usually conducted in the winter.
“This can be a good option for landowners who wish to burn small areas, but we need other options for bigger, more complex burns” Quinn-Davidson said.
In other parts of the country, landowners have formed Prescribed Burn Associations (PBAs) that allow landowners to work with neighbors and other community members on controlled burns, sharing equipment and labor while developing skills. The PBA model provides a low-cost, grassroots option for prescribed burning, and empowers landowners to work together, and with other key experts and partners, to bring fire back to the landscape, says Quinn-Davidson.
“People are desperate to do something about fire, and the PBA model gives them an option to actively engage with each other and with fire as a tool—it's very empowering,” said Quinn-Davidson.
UC scientists, students and water agency professionals took a critical look inwards and a radical look outwards when they gathered in Sacramento in October to reimagine California water.
The event was the fourth annual gathering sponsored by UC ANR's California Institute for Water Resources and the University of California Water Security and Sustainability Research Initiative, UC Water.
While science is the hallmark of a research-oriented institution like UC, the participants were asked to recognize their important role not just as scientists but also communicators.
“We have a big role in educating the public,” said Roger Bales, engineering professor at UC Merced who has been active in water and climate research for more than 30 years. “Scientists are political actors. Facts do not speak for themselves.”
Felicia Marcus, chair of the California Water Resources Control Board and a conference panelist, asked the scientists to make their work accessible, and if they are uncomfortable with plain language, “write it both ways.”
“Complexity can lose people easily,” she said.
The conference keynote speaker, futurist Kim Stanley Robinson, also addressed the divide between scientific discourse and popular understanding, in particular when speaking about climate change.
“There is a strange disconnect between what the scientific community is telling the world and what the world is hearing. As a result of data analysis, science is announcing to the world there is climate change. Individuals cannot perceive climate change,” he said. “Show them in ways that can be understood by the senses. The story has to be told with pragmatism and common sense.”
The Reimagining California Water Conference pursued the water journey from the high-mountain headwaters of the Sierra Nevada to the vast groundwater basins in the valleys below. Over the last century, the mountains were blanketed with snow each winter, storing water that melted slowly in the spring and summer to provide a reliable source of water for farming and communities below. However, climate change is telling a new tale. Warmer weather means less snow and more rain will fall on the mountains during the winter. The quick runoff must be managed in a way that preserves it for use in the summer.
“We need groundwater recharge because we're losing the snow pack quicker than we thought we would,” Bales said.
The new California water narrative has prompted scientists and policy makers to take a serious look at the potential for “flood-managed aquifer recharge” or Flood-MAR. Flood-MAR is a management strategy that uses water from rain or snowmelt to flood agricultural lands and working landscapes, such as refuges, floodplains and flood bypasses.
Successful implementation of Flood-MAR requires the identification of land for groundwater recharge, understanding the economic and agronomic impact of using agricultural land for recharge, and impacts of high-volume recharge on groundwater quality. But the potential is enormous.
“The state's underground basins are capable of storing 500 million acre-feet of water,” said Graham Fogg, UC Davis professor of hydrogeology. “That's like 500 Folsom reservoirs.”
Though the enormity of rewriting the California water story might seem an insurmountable challenge, panelist Debbie Franco noted that the passage of Sustainable Groundwater Management in 2014 happened when the state's unsustainable reliance of groundwater spiked during the 2011-2016 drought, reducing municipal water quality, drying domestic wells and causing land to sink.
“What seems impossible, after four years of drought, can be possible,” Franco said. “What will be the next thing? Get a sense of the solutions now.”
“When first-generation ranchers succeed, we all succeed,” says Kate Munden-Dixon, a Ph.D. student working with Leslie Roche, Cooperative Extension rangeland specialist with the UC Division of Agriculture and Natural Resources and the UC Davis Department of Plant Sciences.
Munden-Dixon and Roche recently discovered that many new livestock managers aren't plugged into information networks such as UC Cooperative Extension and rancher coalitions that provide science and strategies for making sustainable rangeland management decisions. This lack of connection can make first-generation ranchers more vulnerable when dealing with challenges like drought and climate variability, according to their study, which was recently published in Rangeland Journal.
To help bridge the gap, Munden-Dixon landed a $25,000 Graduate Student Grant from Western Sustainable Agriculture Research and Education, a USDA program, to reach out to new ranchers and rangeland managers.
Why rangelands matter
More than one half of California — 38 million acres — is rangeland that provides open space, healthy watersheds, carbon storage, food, fiber and habitat for diverse plants and wildlife. UC Davis research indicates grasslands and rangeland have become more resilient at sequestering or consuming carbon dioxide pollution than forests in California, making them especially important in a warming world.
But rangeland and livestock production are at risk because more rangeland is being converted to housing and crop production. The average age of ranchers in California is 62, and fewer children are taking over the family ranch.
Enter a new wave of rangeland managers. Many of these young ranchers don't yet have access to the capital required to purchase land and large head of cattle and other livestock. Instead, they often contract with public and private landowners to graze goats, sheep and cattle to restore landscapes and reduce fire vegetation.
“What we really need is support in connecting land and contract opportunities,” says Brittany Cole Bush, an “urban shepherdess” and former contract sheep and goat grazer. She now consults with land owners and public agencies from her home base in Southern California. “We need market research that shows the value that grazing brings to fire abatement, soil conservation and so much more. Market research would increase our value and help us become viable players.”
Munden-Dixon is interviewing 40 new rangeland managers from across California to explore how decision-making by different demographics influences adaptation to climate change and quality of life. Munden-Dixon and her team are also hosting workshops to make sure Cooperative Extension specialists understand and can respond to all ranchers' needs.
“There is both a need and opportunity for a new generation of livestock managers that is able to adapt to California's changing climate,” Munden-Dixon says. “This next generation may not look like your typical rancher, so we want to ensure organizations are helping all ranchers succeed, regardless of their demographics or land tenure.”
The power of connection
Munden-Dixon would like to become a Cooperative Extension specialist herself one day. Working with first-generation ranchers reminds her that collaboration and public engagement are critical to addressing issues in sustainable agriculture.
“There is no one answer or single expert when it comes to building healthy food systems,” Munden-Dixon says. “We find solutions when we work together.”
Berkeley — With a body the size of a fist and wings that span more than a foot, the big brown bat must gorge on 6,000 to 8,000 bugs a night to maintain its stature. This mighty appetite can be a boon to farmers battling crop-eating pests.
But few types of bats live on American farms. That's because the current practice of monoculture – dedicating large swathes of land to a single crop – doesn't give the bats many places to land or to nest.
Diversifying working lands – including farmland, rangeland and forests – may be key to preserving biodiversity in the face of climate change, says a new review paper published this week in Science by conservation biologists at the University of California, Berkeley.
Diversification could be as simple as adding trees or hedgerows along the edges of fields, giving animals like birds, bats and insects places to live, or as complex as incorporating a patchwork of fields, orchards, pasture and flowers into a single working farm.
These changes could extend the habitat of critters like bats, but also much larger creatures like bears, elk and other wildlife, outside the boundaries of parks and other protected areas, while creating more sustainable, and potentially more productive, working lands.
“Protected areas are extremely important, but we can't rely on those on their own to prevent the pending sixth mass extinction,” said study co-author Adina Merenlender, a UC Cooperative Extension Specialist in the Department of Environmental Science, Policy and Management at UC Berkeley. “This is even more true in the face of climate change, because species will need to move around to adapt to shifts in temperature and climate.”
A win-win for wildlife and for farms
Maintaining even small pieces of the original landscape – even a single tree– can help conserve the original diversity of species, Merenlender said. Clearing oak woodlands and shrublands to establish large vineyards hits many native species hard. Animals that are well adapted to urban and agricultural areas, such as mockingbirds, house finches and free-tail bats, continue to flourish, while animals that are more sensitive to disturbance, like acorn woodpeckers, orange-crowned warblers and big brown bats, begin to drop away. “If you can leave shrubs, trees and flowering plants, the habitat suitability -- not just for sensitive birds but also for other vertebrates – goes way up,” Merenlender said. This is true not only in California's vineyards, but on working lands around the world.
Incorporating natural vegetation makes the farm more hospitable to more creatures, while reducing the use of environmentally degrading chemicals like herbicides, pesticides and man-made fertilizer.
The ideal farming landscape includes woodland pastures and vegetable plots bumping up against orchards and small fields, said Claire Kremen, a professor in the Department of Environmental Science, Policy and Management. Integrating livestock produces manure which can fertilize the crops, while those same crops produce feed for livestock. Birds and bats provide pest control, and bees boost crop production by pollinating plants.
“It is possible for these working landscapes to support biodiversity but also be productive and profitable,” Kremen said. “And ultimately, this is where we have to go. We just can't keep mining our soils for their fertility and polluting our streams – in the end, this will diminish our capacity to continue producing the food that we need. Instead, we must pay attention to the species, from microbes to mammals, that supply us with critical services, like pollination, pest control and nutrient cycling”
“We have some amazing diversified farms, sustainably managed forests and species-rich rangelands here in California that exemplify working lands for conservation around the world,” Merenlender said. “We are calling for a scaling up of this approach around the world, and to do that we champion community-based action and more supportive polices” Kremen concludes.
Claire Kremen, firstname.lastname@example.org, 510-367-2100 (cell)
Adina Merenlender, email@example.com, (707) 489-4362
Overall, 3.5 percent of the trees (based on those areas sampled during the blitzes) were found to be P. ramorum positive, a threefold drop from 2017. Yet, in San Mateo, Santa Clara and Santa Cruz counties, infection levels were estimated to be as high as 19 percent, followed by 12.7 percent in the East Bay.
"Oaks and tanoaks were infected last year and will be showing symptoms such as bleeding in the stem and canopy drying this year and in the next two years to follow. Hence, despite a reduction of SOD infection on leaves of California bay laurels and leaves of tanoaks in 2018, we can expect a sharp increase in oak and tanoak mortality in 2018, 2019 and 2020."
Notable outbreaks were detected in Alameda (El Cerrito and Oakland urban parks, San Leandro, Orinda, Moraga), Marin (Novato, Day Island, Woodacre, Sleepy Hollow, McNears Beach, China Camp State Park, north San Rafael, Tiburon Peninsula, east and west peak of Mt. Tamalpais, Marin City), Mendocino (south of Yorkville), Monterey (Carmel Valley Village, Salmon Creek Trail in southern Big Sur), Napa (east Napa city), San Mateo (Burlingame Hills, west of Emerald Hills and south of Edgewood Rd, Woodside ), Santa Clara (Los Altos Hills, Saratoga, Los Gatos, along Santa Cruz Co border), Santa Cruz (along the Santa Clara Co border, Boulder Creek), and Sonoma (near Cloverdale, east and west of Healdsburg, west of Windsor, east of Santa Rosa, west of Petaluma) counties.
Several popular destinations where P. ramorum was found positive during the 2017 Blitz were negative for the pathogen in 2018, including Golden Gate Park and the Presidio of San Francisco, the UC Berkeley campus, and Mount Diablo State Park. Samples from San Luis Obispo and Siskiyou counties were also pathogen-free as were those from the southern portion of Alameda County.
“It is encouraging that SOD has yet to be found in the forests of California's northern-most counties, San Luis Obispo County and southern Alameda County,” said Garbelotto.
“It is also encouraging to see that despite its continued presence in the state for more than 20 years, SOD infection rates drop during drier years,” he said. “However, in 2018, we identified a number of communities across several counties where significant outbreaks were detected for the first time, and the Salmon Creek find in Monterey County is the southernmost positive WUI (wildland-urban interface) tree detection ever. Until the 2018 Blitz, only stream water had been found positive in the Salmon Creek area. We encourage everyone in affected counties to look at the Blitz results online and to attend one of the fall workshops to learn how to protect their oaks from SOD.”
Citizen-science SOD Blitz workshops
SOD Blitz Workshops are being held this fall in Santa Rosa (Oct. 10), Portola Valley (Oct. 16) and Berkeley (Oct. 17). The trainings will discuss Blitz results and recommendations for protecting oaks in the WUI. Workshops are intended for the general public, tree care professionals and land managers (see www.sodblitz.org for details). Two International Society of Arboriculture continuing education units will be offered at each training. Data collected from the Blitz (both positive and negative samples) have been uploaded to the SOD Blitz map (www.sodblitz.org ) as well as to SODmap (www.SODmap.org) and to the free SODmap mobile app, which can serve as an informative management tool for people in impacted communities.
Twenty-five SOD Blitz surveys were held in 2018 in the WUI of 14 coastal California counties from the Oregon border to San Luis Obispo County and included three tribal land surveys. The 304 volunteers surveyed approximately 13,500 trees and submitted leaf samples from over 2,000 symptomatic trees to the Garbelotto lab for pathogen testing.
SOD Blitzes are a citizen science program, which train participants each spring to identify symptomatic tanoak and California bay laurel trees in the WUI and to properly collect samples in the interest of generating an informative map of P. ramorum disease symptoms over time. Samples are tested for the presence of the pathogen at UC Berkeley and results are posted electronically each fall. Now in its eleventh year, the SOD Blitz program is one of the first in the world to join researchers and volunteers in a survey for a tree disease.
SOD Blitz surveys were made possible thanks to funding from the US Forest Service State and Private Forestry, Midpeninsula Regional Open Space District, and the PG&E Foundation. The Blitzes were organized by the UC Berkeley Garbelotto lab in collaboration with the National Park Service, Presidio Trust, San Francisco Public Utilities Commission, Midpeninsula Regional Open Space District, Save Mount Diablo, Land Trust of Santa Cruz County, East Bay Regional Park District, Santa Lucia Conservancy, Sonoma State University, UC Santa Cruz Arboretum, Los Padres National Forest, City and County of San Francisco Department of Recreation and Parks, UC Berkeley Botanical Garden, and California Native Plant Society.
For information on the status of P. ramorum/SOD tree mortality in California wildlands, see the US Forest Service 2018 Aerial Detection Survey results at https://www.fs.usda.gov/detail/r5/forest-grasslandhealth/?cid=fseprd592767.
For more information on the SOD Blitzes, visit www.sodblitz.org or contact Katie Harrell at (510) 847-5482 or firstname.lastname@example.org. For more information on Sudden Oak Death and P. ramorum, visit the California Oak Mortality Task Force website at www.suddenoakdeath.org or contact Harrell.