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UC Cooperative Extension ramps up its climate change response

While scientific reports continue to mount confirming that global climate change is increasing temperatures, causing more frequent weather extremes and raising the sea level in California, UC Cooperative Extension is working to ensure the worst predictions are avoided and California residents and businesses will be able to adapt to the change.

Each year, a diverse group of UC Agriculture and Natural Resources academics and program implementation professionals meet to share and collect the latest climate change experiences, ideas, science and solutions. The team works with farmers across the state to improve production practices and minimize environmental impact, conduct agricultural and natural resources conservation research, and coordinate programs like California Naturalist and UC Master Gardener, which recruit and educate volunteers to reach out to communities statewide to extend research-based information.

A possible climate change outcome in California may be returning farmland to less-intensive uses, such as grazing.

Reaching real people

In 2019, extension practitioners explored new approaches to delivery of information and services. For example, the first speaker addressed the way climate change impacts may be viewed through the lens of African-American or First Nation experiences, influenced by poverty, historical trauma and even spirituality.

Theopia Jackson, clinical psychologist at Saybrook University in Oakland, encouraged the team to consider whether assisting Americans navigating the changing climate or suffering the consequences of extreme weather events have “the bandwidth to take in one more helping hand.” Jackson has a long history of providing therapy services, specializing in serving populations coping with chronic illness and complex trauma.

Jackson suggested helpers ask themselves, “Are we inadvertently causing more stress than good? Do I have a sense for what they are already dealing with before bringing something new into the community?”

Jackson said the conversation about climate change in many communities might be more productive focused less on whether climate change exists or not, and instead on how to “join with them around the human experience.”

“If I'm trying to ‘talk them into it,' I need to step back,” Jackson said. “The conversation could be about scarcity or lifestyle. We need to find a way to join and hope they will get it before we've done irreversible damage.”

The careful selection of terminology and approach in climate change conversations was also raised by Dan Sonke, director of sustainable agriculture for Campbell's Soup. The company's primary and best-known product is soup, but it owns other familiar brands, including Pepperidge Farms, Snyder Pretzels, Kettle Chips and Emerald Nuts.

In California, Sonke works closely with farmers producing fresh produce to be used in Campbell's products, particularly processing tomatoes. During his career, he also worked in Campbell's marketing, based on its “corporate purpose.”

“We make real food for real people,” says the Campbell's corporate purpose. “People love that our food fits their real lives, fuels their bodies, and feeds their souls. And they appreciate knowing what goes into our food, and why — so they can feel good about the choices they make, for themselves and their loved ones.”

Sonke was hired to increase the use of sustainable farming practices by the company's producers and help farmers apply for grant funding from the state to implement climate-smart irrigation practices. The company was able to track a 20 percent reduction in water use and document a significant reduction in the emission of nitrous oxide, a greenhouse gas. The program is successful, but isn't driving their farmer communications or soup sales, Sonke said.

“Farmers don't think in terms of climate change, but they respond to what they know,” Sonke said. “Consumers don't respond to climate change adaptation in terms of what products they buy. They respect sustainability, but have no understanding of ‘sustainable agriculture' and ‘carbon sequestration.'”

More extreme weather events - such as heavy rain, flooding, cold snaps and heat waves - are expected due to climate change.

Growing UCCE climate mitigation, adaptation and resilience programs

UC ANR is working on new ways to reach out to farmers and the public with information on climate change. Six community education specialists have been hired and four more are being recruited to work in counties around the state to help farmers access programs that will help them reduce greenhouse gas emissions on farms and dairies, build resilience to climate change and increase profit.

The Climate-Smart Farming Program is a collaborative effort with the California Department of Food and Agriculture focused on implementing on-farm solutions to improve soil health, nutrient management, irrigation management, on-farm composting and manure management.

The CDFA programs involved are:

The new community education specialists are already deployed in Mendocino, Glenn, Yolo, Santa Cruz, Ventura and San Diego counties. The four positions under recruitment will serve Imperial, San Joaquin, Fresno and Kern counties. To get information about these programs, contact:

Climate stewards

To reach a broad swath of California residents with research-based information on climate change mitigation and adaptation, UC ANR's California Naturalist program is leveraging its well-established partnerships with formal and informal science education institutions across the state to create a legion of climate stewards. At the team meeting, CalNat coordinator Greg Ira announced that the California Naturalist program has hired an academic coordinator to develop curriculum that will allow existing partners to deliver the material as part of the California Naturalist program. The graduates of this California Naturalist course focused on climate change will be encouraged to engage in volunteer service that helps build community resilience to climate change. These include participation in local adaptation planning efforts, community and citizen science projects, or addressing issues of social justice. The coordinator begins Feb. 19.

Areas where peaches and cherries have flourished in the past may no longer provide adequate winter chilling due to climate change.

The future

Renata Brillinger of the California Climate Action Network shared optimistic thoughts about the opportunities for climate change mitigation, adaptation and resilience. In terms of politics, she said California leadership has accepted climate change as a settled matter and are supportive of programs to address the issue. At the federal level, it is not easy to talk about climate change, but “that will change,” she assured.

Brillinger said biodiversification of California is an exciting area for climate change adaptation. Research is needed to understand how to shift crop locations for future production, and determine where, for example, water-intensive crops or orchards with chill requirements should be grown. More information is needed, she said, on how healthy soil will relate to climate resilience in agriculture.

 “We have to reinvest in extension and Resource Conservation Districts,” Brillinger said.

Other possible climate change outcomes in California may be returning farmland to less-intensive uses, such as grazing. Fallowing land was one way that the agriculture industry coped with the drought of 2011-16, and implementation of the Sustainable Groundwater Management Act – a direct result of the drought – is estimated to take 1 million acres of farmland out of production. This approach won't be a solution for all farmers and ranchers, said David Lile, UC Cooperative Extension natural resources advisor.

“Ranchers and farmers interested in long-term sustainability, keeping the farm in place, will need help to integrate competing forces,” Lile said. “Economics will not be the only driving force.”

Posted on Wednesday, January 30, 2019 at 8:36 AM
Tags: Climate change (35)
Focus Area Tags: Agriculture Natural Resources

New Cannabis Research Center to explore environmental, social impacts of legalization

 

A new Cannabis Research Center will be directed by Van Butsic and Ted Grantham, both UC Cooperative Extension specialists in UC Berkeley's Department of Environmental Science, Policy and Management. (UC Berkeley graphic by Hulda Nelson)

Cannabis is unlike any other agricultural crop. Because of its circuitous history — once illegal to grow, and now legal but heavily regulated — cannabis has cast a unique footprint on the environment and the communities of farmers who grow it.

UC Berkeley's new Cannabis Research Center, announced today by a multidisciplinary team of faculty, will explore how cannabis production impacts the environment and society, and how these impacts will evolve under new regulations set in place by legalization.

While other research groups in the University of California are focusing on the individual and public health ramifications of cannabis, the center will be the first in the UC system to explore oft-overlooked dimensions of cannabis growth.

Berkeley News spoke with center co-directors Van Butsic and Ted Grantham, both assistant cooperative extension specialists in UC Berkeley's Department of Environmental Science, Policy and Management, to learn more about the state of cannabis production in California and the center's goals.

A small cannabis-producing farm in Northern California. Photo by Ted Grantham
Berkeley News:  What are some of the ecological and community impacts of cannabis production?

Ted Grantham: My research primarily focuses on the impacts of water use. These farms are taking water directly from streams or from groundwater wells connected to streams. Most farms are located in smaller watersheds, so even though the total amount of water taken can be small, it can have a big impact on streams that support sensitive species, such as salmon. Other potential ecological impacts relate to the use of pesticides and fertilizers, and habitat fragmentation from building roads and clearing trees.

The social scientists in the center are also concerned about equity and the sustainability of growing communities. Historically many growers would be characterized as small-scale, and there is concern that through this process of legalization, there is going to be a consolidation of cannabis production following models of industrial agriculture. We are trying to understand if there is a way to have cannabis cultivation continue to sustain local economies and rural communities, while limiting impacts to the environment.

How have legalization and associated regulations affected cannabis production so far?

Van Butsic: We're about a year into the formal legalization of recreational cannabis production and it has been a rocky start. There have been fewer participants in the market — producers — than were anticipated. Some growers appear to have gone out of production, many appear to remain in black market production and a relatively small subset of growers have gone through the process of compliance. And the grower community that has pursued legal production are very vocal about the issues and challenges facing their group. We have been trying to better understand what are the barriers to compliance and, ultimately, if there can be changes made in policies that can really help to catalyze this transition.

Tree leaves and needles are removed because they block sunlight needed for marijuana plants. Pacific Southwest Region 5 photo, via Flickr
Cannabis production makes up only a very small percentage of agriculture in California. Why is it important to study its impacts in particular? 

Van Butsic: This is a great system to study really big sustainability problems. How do we develop an agricultural system that's good for the environment and good for farmers?  And cannabis is a really interesting spot to look at it because the regulations enforcing cannabis are totally different than in the rest of agriculture, so it would be really interesting to see if we get different outcomes.

How do regulations differ between cannabis production and the rest of agriculture?

Van Butsic: Cultivators need to be permitted by the state water board, by local government and by state government to grow cannabis legally, and there are environmental regulations in all three of those levels that they need to comply with that require a higher order of environmental performance than most other agricultural crops.

So you think that understanding these regulations might help you apply them to other types of agriculture?

Van Butsic: Exactly. Agriculture has been notoriously difficult to regulate in the past, and this is a system where the regulators got the upper hand, and so it will be interesting to see how the producers respond, and if cannabis producers can be profitable and meet these super-high environmental performance measures, then perhaps there is knowledge and technology that can transfer from the cannabis industry to the rest of agriculture that can improve environmental performance of food production.

We are working on a big project right now where we are mapping where all the farms are after the latest regulatory changes. We want to know, if we could take down these barriers and everybody became compliant, what would that mean for local water budgets, environmental health and for the amount of cannabis that would be produced?

Ted Grantham: This is a rapidly changing industry, and no one really knows where it is headed. Everyone is playing catch up to a certain extent, and we believe researchers have an important role in bringing independent scientific information to conversations around cannabis policy.

Posted on Tuesday, January 29, 2019 at 2:18 PM
  • Author: Kara Manke
Tags: cannabis (2), Ted Grantham (4), Van Butsic (4)
Focus Area Tags: Environment

Livestock grazing helps California tackle wildfire

California is searching for solutions to the wildfire crisis. Livestock ranchers believe they can help.

At the 14th Annual Rangeland Summit in Stockton in January, more than 150 ranchers, public land managers and representatives of non-profit organizations that work on land conservation gathered to share research and experiences that outline the value of cattle and sheep grazing on rangeland.

Since California was settled by Europeans, cattle and sheep have been an integral part of the state's history.

“Cattle can control brush,” said Lynn Huntsinger, UC Cooperative Extension specialist at UC Berkeley in a presentation on brush management. She discussed research she conducted in the early 1980s to understand the role of cattle in Sierra Nevada brush control.

“We need to make livestock into firefighters,” she said. “Constant, deliberate, targeted grazing is needed for fire management.”

However, thick, overgrown brush requires intensive treatment that cattle can't handle on their own.

“You have to start from a good place,” Huntsinger said. “Start early, such as post fire. Plan when you have a blank slate for the forest you want.”

UCCE specialist Lynn Huntsinger suggested cattle may be viewed as a team of firefighters.

The tragic loss of homes and lives to wildfire in the last few years has increased the public demand for answers and action. However, the reasons for greater frequency and intensity of wildfire are not well understood.

“Is it climate change? Past decisions? Land use? What can we do about it?” asked UC Cooperative Extension specialist Van Butsic. “Research.”

At the summit, Butsic presented the results of his recent research to determine whether ownership has an impact upon whether land will burn. He and his colleagues studied the burn histories of forest and rangeland areas that were matched with the same characteristics, except in ownership.

“We controlled for all factors – slope, elevation, the likelihood of ignition,” he said. “We found that on forest and rangeland, federal ownership led to .3 percent higher fire probability. Ownership is dwarfing the impact of climate change.”

There is still much more research to be done.

“We can't say the impact of grazed vs. ungrazed land,” Butsic said. “We also need to look at fire severity as well as fire frequency.”

Research by UCCE advisor Laura Snell and her colleagues showed that rangeland doesn't need to be 'rested' following a fire.

The UC Cooperative Extension advisor in Modoc County, Laura Snell, shared preliminary results at the rangeland summit that provide information for landowners making decisions about returning livestock to burned areas.

She and a team of colleagues studied the fire history of U.S. Forest Service and Bureau of Land Management rangeland in Lassen and Modoc counties where fires had burned through 5, 10 and 15 years before. The dataset included information about whether the land was “rested” for two years after the fire, or whether livestock were returned to graze soon after the blaze.

The scientists set out to determine whether fire intensity and climate at the site (measured by soil temperature and moisture) had an impact on the future diversity of plant species and growth of cheat grass, an invasive species that animals don't like. 

“No matter what we did, graze or not graze, after 15 years, the species richness stayed the same,” Snell said. “Grazing was not the driving factor.”

The results are also important in terms of fuels accumulation and the prevention of future wildfires.

“Federal land managers have typically used a policy to rest the land for two years after a fire. During the interval, the fuels sometimes burn again and livestock producers have to wait another two years,” Snell said. “Our research showed you don't necessarily need to rest the land after the fire.”

Sheep and cattle grazing can reduce the fuel load for a potential wildfire. (Photo: Dan Macon)

Two ranchers who were recently impacted by wildfire presented their experiences and perspectives during the rangeland summit.

Mike Williams of Diamond W Cattle Company had livestock on 6,500 acres of leased land in Ventura County when the Thomas Fire ignited on Dec. 4, 2017. Over more than a month, the fire burned 281,893 acres and consumed 1,000 structures.

Williams had stockpiled feed on certain pastures by limiting grazing, which during the fire turned into hazardous fuel.

Adam Cline, rangeland manager for the Yocha Dehe Wintun Nation Preserve in the Capay Valley, had a similar experience when the County Fire burned more than 90,000 acres in western Yolo and eastern Napa counties in June and July 2018. To reserve feed for later, Cline had left 2,500 pounds per acre of residual dry matter on grazing land as a drought mitigation strategy. He said he plans to reconsider this grazing plan.

“Now, cattle feed looks like a lot of fuel,” he said.

Posted on Tuesday, January 22, 2019 at 8:40 AM
Tags: cattle (7), Laura Snell (2), Lynn Huntsinger (4), rangeland (14), sheep (5), Van Butsic (4), wildfire (35)
Focus Area Tags: Environment

Documenting urban nature in the City Nature Challenge

Have you ever been on a walk and observed an interesting plant you couldn't identify? Encountered an unusual insect trapped in your home? Have you wondered why you used to see certain species in nature and you don't now? Or have you thought it might be neat to compile a species list for a special place, like a favorite park or your own backyard? All California Naturalists already know that there's an app (and website) for all that!

What is iNaturalist?

The free iNaturalist app is an online social network of people sharing biodiversity information to help each other learn about nature. Available for android, iPhone, and by a website, iNaturalist is a joint initiative by the California Academy of Sciences and the National Geographic Society that allows users to upload one or more pictures, provide a location, and make relevant notes like whether the subject is captivate or wild.

In response, the artificial intelligence in the app suggests what the species might be based on visual similarity and whether the species has been observed nearby. Members and organizations can set up projects and download data within defined taxa or locations to follow presence and absence, abundance, seasonality and change over time.

All California Naturalists use the iNaturalist app.

Verified observations are sent to the Global Biodiversity Information Facility, an international network and research infrastructure funded by the world's governments and aimed at providing anyone, anywhere, open access to data about all types of life on earth. Valuable open-source data is available to aid scientific research, government and conservation organizations, and the interested public. Nearly instant gratification for species ID combined with the ability of members to contribute to a greater good whenever they venture outdoors are huge motivators for much of the existing iNaturalist community, which currently exceeds one million users and 14 million observations.

iNaturalist observations and the upcoming City Nature Challenge

One of the biggest BioBlitzes naturalists and others can participate in is the annual City Nature Challenge. The City Nature Challenge — essentially a four-day global urban bioblitz — began in 2016 as a friendly nature-observation competition between the San Francisco Bay Area and Los Angeles County, organized around a simple charge: “which city can find the most nature?” Participants use the iNaturalist app to photograph, catalog, identify and organize observations of wildlife in their areas. The city with the highest number of observations wins. Since the first challenge, the competition has expanded rapidly, and this year more than 150 cities will participate worldwide.

How does it work?

The City Nature Challenge takes place April 26-29, 2019. During this window, anyone can contribute observations via iNaturalist. There will are also be a variety of events organized to help cities win the challenge. Cities are competing against each other to see which city can make the most observations of nature, find the most species, and engage the most people. At the end of the observation window on April 29, other events will be held to help participants identify and complete their observations in iNaturalist. 

A California Naturalist from the Dominguez Rancho Adobe course takes a photo to upload to iNaturalist.

How can we participate in 2019?

The UC Agriculture and Natural Resources' California Naturalist program is teaming up with the UC Davis School of Education's Center for Community and Citizen Science, UC Davis Evolution and Ecology Department, and other partners in the region to put the Sacramento region in the competition for the first time. Stay updated and learn more information about how to join the fun on the Sacramento City Nature Challenge website as we add events. Experienced and beginner naturalists alike are invited to attend these events.

For those outside of the Sacramento region, participate in the Natural History Museum of LA County's Los Angeles County City Nature Challenge, San Diego Natural History Museum's San Diego County City Nature Challenge, and the California Academy of Sciences' San Francisco Bay Area City Nature Challenge. All you have to do is log in to your account and join the project. Any observations uploaded from within the project boundaries from April 26-29 are automatically contributed to the challenge.

Last year, 6 percent of the nearly 7 billion total observations uploaded to iNaturalist were contributed during the City Nature Challenge, making the challenge the single-most uploaded period of 2018. With the City Nature Challenge growing internationally in 2019, even more observations will be added in the hopes of getting more people outside, engaging with the natural spaces within urban environments, spending time with fellow nature enthusiasts and community organizations, and learning and contributing to science.

California Naturalists learn to identify flora and fauna using iNaturalist at the UC Berkeley Sagehen Creek Field Station.
Posted on Tuesday, January 8, 2019 at 9:01 AM
Focus Area Tags: Environment

Is habitat restoration actually killing plants in California wildlands?

In 2014, plant biologists with the California Department of Agriculture reported an alarming discovery: native wildflowers and herbs, grown in nurseries and then planted in ecological restoration sites around California, were infected with Phytophthora tentaculata, a deadly exotic plant pathogen that causes root and stem rot.

While ecologists have long been wary of exotic plant pathogens borne on imported ornamental plants, this was the first time in California that these microorganisms had been found in native plants used in restoration efforts. Their presence in restoration sites raised the frightening possibility that ecological restoration, rather than returning disturbed sites to their natural beauty, may actually be introducing deadly plant pathogens, such as those related to Sudden Oak Death, into the wild.

New work by a UC Berkeley team in the College of Natural Resources shows for the first time just how widespread and deadly the threat of pathogens from restoration nurseries may be.

The exotic soilborne Phytopthora cinnamomi was introduced in the Ione area of the Sierra Nevada foothills, where it is literally wiping out two native manzanita species. This picture shows how vehicles spread the pathogen along roads and tracks by kicking up infected soil, killing nearby manzanita. (Photo: Matteo Garbelotto)

The team surveyed five native plant nurseries in Northern California and found that four harbored exotic, or non-native, Phytophthora pathogens. Strains of the pathogens from native plant nurseries were shown to be at times more aggressive than strains found in the wild, and some of them are rapidly developing resistance to the fungicides that can be used to control them, the researchers found.

Working with restoration nurseries around the state, the researchers showed that new management techniques, coupled with new methods for detecting pathogens, can help these nurseries limit the spread of exotic pathogens.

"Some of these restoration projects cost tens of millions of dollars, but of course their actual value is much higher, because of the wealth of services healthy natural ecosystems provide, including supporting animal and plant biodiversity, providing good water and air quality, and enjoyable recreation sites," said Matteo Garbelotto, UC Cooperative Extension specialist and adjunct professor of environmental science, policy and management at UC Berkeley.

"Such services are highly diminished in ecosystems affected by exotic plant diseases, while water runoff and erosion, the establishment of exotic plants and animals, and even hotter wildfires may increase in conjunction with disease outbreaks in natural ecosystems," Garbelotto said.

Pathogens evolve to outwit fungicides

Bacteria that make humans sick are constantly evolving to resist the antibiotics designed to fight them, and resistance to fungicides has been documented in microbes causing diseases in agricultural plants. Garbelotto and his team wanted to know if the widespread use of fungicides in in native and ornamental plant nurseries could also accelerate the development of fungicide-resistance in plant pathogens.

Their research was spurred in part by their discovery of a new strain of the Sudden Oak Death pathogen in Oregon forests that is highly tolerant of a fungicide commonly known as phosphite, one of the main weapons used against plant parasites in the wild because its application does not cause any known negative environmental side effects.

Together with a group of New Zealand researchers, they decided to study fungicide resistance of Phytophthora -- a genus of plant pathogens that can case lethal cankers and root rot -- to two important fungicides, including phosphite.

The researchers gathered numerous samples of Phytophthora from 11 species present both in forests and plant nurseries. They then tested the sensitivity to phosphite of multiple individuals per species.

While most of the species tested were overall still sensitive to phosphite, strains of four species were able to resist the effects of the chemical, the researchers report in PLOS ONE. These include Phytophthora ramorum, the parasite behind Sudden Oak Death in North America and Sudden Larch Death in Europe, and Phytophthora crassamura, a species first discovered recently by the same UC Berkeley researchers in native plant nurseries and restoration sites in California.

Some strains within each of these four species, although genetically almost identical to strains still susceptible to phosphite, were resistant to it. The presence of chemical tolerance or chemical sensitivity when comparing nearly genetically identical strains suggests that the development of resistance occurred relatively recently, perhaps in response to the widespread use of phosphites in native and ornamental nurseries, Garbelotto said.

"These pathogens can be literally flooded with these chemicals in plant production facilities, and at the beginning of the study, we hypothesized that in such predicaments these pathogens would be forced to evolve resistance" Garbelotto said. "Indeed, our hypothesis was correct, and we found that some of them evolved the ability to tolerate exposure to phosphite."

While phosphite can still help to spur a plant's immune system, this may not be enough to quell the spread of the disease, Garbelotto said.

"By pressuring these pathogens to evolve resistance to phosphites, we are effectively taking out phosphite as a potential tool to manage these disease outbreaks," Garbelotto said. "Furthermore, the ability to quickly develop tolerance to a fungicide may be an indication these pathogens can adapt quickly to new environments. Thus, they may become formidable invasive organisms, infesting larger swaths of natural areas and causing significant disease and mortality of essential native flora."

A widespread - but reparable - problem.

Since the first discovery of Phytophthora in California restoration sites, research by the UC Berkeley team and others have traced the deaths of wild trees and plants back to strains of the pathogen originating in native plant nurseries, rather than strains already found in the wild. However, few studies have documented just how prevalent the problem is.

In a recent study published in the journal Plant Pathology, UC Berkeley researchers examined 203 individual plants across five restoration nurseries in California and found that 55 of the plants were infected with Phytophthora.

"We were able to prove that this is a widespread problem in California," Garbelotto said. "Most of the stock that they used is infested, and the levels were very high. For some species more than 50 percent of the plants we tested were infected."

The team then worked with the infected nurseries to implement new best management practices to try to limit the spread of disease without the use of phosphite or of other fungicides. These simple guidelines, which included more careful management of water runoff and soil to reduce cross contamination, reduced the prevalence of disease to nearly zero a year after implementation.

"We were able to prove that after a year of following the guidelines, those facilities were clear of pathogens, and other facilities that did not follow the guidelines still had the pathogens," Garbelotto said. "As a result of these findings, people are now putting a lot of money and effort into making sure that the plants are clean, by following similar guidelines and by making sure that no fungicides are used to avoid the development of resistance."


Co-authors on the PLOS ONE study are Shannon Hunter of the University of Waikato in New Zealand and Nari Williams, Rebecca McDougal and Peter Scott of Forest Protection in New Zealand. Co-authors on the Plant Pathology study are L. Sims of UC Berkeley and S. Tjosvold and D. Chambers of the University of California Cooperative Extension.

This research was supported by the Endemic and Invasive Pests and Diseases Strategic Initiative of the University of California, Agriculture and Natural Resources; and by the San Francisco Public Utilities Commission in collaboration with the U.S. Forest Service (Region 5).

Posted on Friday, January 4, 2019 at 10:07 AM
  • Author: Kara Minke, kjmanke@berkeley.edu, (510) 643-7411
Focus Area Tags: Environment

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