Posts Tagged: innovation

Grape seeds, stems and skins can reduce dairy cattle emissions

A UC Davis-led pilot research project, to be detailed in a paper later this year, found that mixing in grape pomace reduced methane emissions, improved feed efficiency and increased healthful fats. Archive photo by Elena Zhukova

Low-cost wine industry additive also improved feed efficiency and milk quality

Researchers at University of California, Davis, added fresh grape pomace left over from winemaking operations to alfalfa-based feed for dairy cows and found that methane emissions were reduced by 10% to 11%.

The preliminary findings could offer a low-cost sustainable pathway for vineyards to reduce waste while helping dairy operations maintain quality while cutting back on emissions of methane, which is a powerful greenhouse gas.

“This is the first time anybody has shown that this can work in California,” said Ermias Kebreab, an animal science professor and associate dean of global engagement at UC Davis. “You're reducing emissions, you're improving the quality and it may also reduce the cost of production.”

The pilot research project, which will be detailed in a paper later this year, also found that mixing in grape pomace improved feed efficiency and increased healthful fats, said Selina Wang, an associate professor of Cooperative Extension in small scale fruit and vegetable processing.

“We found that the feed with the additive of grape pomace changed the fatty acid composition of the milk and, in particular, increased the polyunsaturated fats, which are the main fats in grape pomace,” Wang said. “This suggests that supplementing the feed with an optimal fatty acid profile may have positive impact on the fatty acid profile of the milk and increase their health benefits.”

Symbiotic commodities?

In 2022, California was the leading dairy producer in the country, generating $10.40 billion in sales, while 90% of wine production came from the Golden State, with a market value of $5.54 billion.

Processing grapes for wine generates thousands of tons of waste in the form of grape pomace, which consists of leftover seeds, skins and stems. Dairy and livestock are responsible for more than half of the state's methane emissions, owed largely to cow burps.

They are the top two agricultural commodities in California, according to state production statistics, and reducing waste and emissions for both industries are key to the state meeting its climate goals.

From left to right: wet, dry, and dry and ground grape pomace. Photo by Edwin Grey, UC Davis

Tannins for emission reductions

Wine grapes are high in fats and tannin, which is known to reduce methane emissions, so Kebreab sought to test if adding grape pomace to feed could have a positive effect while not adversely affecting production.

“It's a byproduct that's not being used much,” he said. “This is something that can be included in our efforts to try to reduce emissions.”

A mix of feed options

To do the research, scientists worked with Holstein dairy cows and gave the animals feed consisting of alfalfa, wheat, almond hulls, cottonseed and grain. After two weeks, the cows were split into three groups: A control group with no change in diet, another where the feed combination included 10% grape pomace and a third that received 15% grape pomace.

Every four weeks, the cow groups would change feed combinations.

They were fed twice daily by postdoctoral students and interns, and emissions were monitored daily. Milk production was documented in the morning and evening and milk samples were collected weekly to analyze for fat, protein, lactose and other measurements, which showed no differences between the control and other groups.

Methane and hydrogen emissions were reduced compared with the control group, suggesting that grape pomace reduced enteric emissions without affecting production.

“I think the dairy industry will be very interested in this,” Kebreab said. “Sometimes when you're using additives, they have palatability issues. With grape pomace, they absolutely love it.”

Next on the list is a trial with olive pomace and working to understand the mechanism that reduces emissions. “If we have a better understanding of the mechanisms, we can select the feed additive or a mix of feed additives to reduce dairy cattle emissions and make dairy milk healthier while making use of the agriculture byproducts,” Wang said. “There's a lot of room to grow in this space and we're excited about this work.”

The research was supported by the California Dairy Research Foundation.

This article was first published on the UC Davis news site.

AI and sustainable farming focus of May 7 workshop with UC, partners

Drip-irrigated date palms in the Coachella Valley. Artificial intelligence may help farmers save water. Photo by Ali Montazar

On May 7, scientists from University of California, Riverside, UC Agriculture and Natural Resources, Colorado State University Extension, Kansas State University, University of Arizona, Central Arizona Project, and USDA-Agricultural Research Service will gather with growers in Palm Desert to discuss how artificial intelligence can be used in agriculture.

“Artificial intelligence can be used by farmers to save water, improve fertilizer efficiency and increase productivity,” said Khaled Bali, UC Cooperative Extension irrigation water management specialist and organizer of the workshop. “At this workshop, growers will hear about the latest research on AI technology for agriculture and about the experiences of growers who are already testing it in their fields.”

Speakers and topics will include:

• Raj Khosla, Kansas State University - AI for precision nitrogen and water management in row crops
• Michael Cahn, UC Cooperative Extension - CropManage decision support tool for irrigation and nutrient management
• Daniele Zaccaria, UC Cooperative Extension - Citrus crop water use and open ET in the low desert of California
• Nan Li, UC Riverside - Estimating soil moisture using remote-sensing and land surface parameters in the Central Valley of California.
• Ali Montazar, UC Cooperative Extension - Promises and pitfalls of drip irrigation in desert cropping systems
• Khaled Bali, UC Cooperative Extension - Deficit irrigation strategies for alfalfa in California
• Philip Waisen, UC Cooperative Extension - Environmentally conscious practices for managing soilborne diseases in low desert vegetable production
• Peter Moller, Rubicon Water - On-farm water conservation projects: surface irrigation
• Ronnie Leimgruber, Imperial Valley grower - On-farm water conservation projects: linear move, basin and subsurface drip irrigation
• Rick Benson, Imperial Valley grower - Alternative cropping systems for the low desert region of California: olives and other crops

The workshop will be held at the UCR Palm Desert Center at 75080 Frank Sinatra Drive in Palm Desertfrom 8 a.m. to 3 p.m. on May 7. It costs $30 per person and includes lunch. Register at https://bit.ly/AImay7.

Organic strawberry yields boosted by technique refined through UCCE research

There is a stark difference in plant vigor between an ASD-treated plot (left) and a standard untreated plot in an organic field infected with charcoal rot. Photo by Joji Muramoto

Anaerobic soil disinfestation helps suppress weeds, disease without fumigants

Troubled by puny plants, low yields and persistent mite problems, third-generation Southern California strawberry grower Glen Hasegawa was ready to give up on his transition from conventional to organic 12 years ago.

“I've always liked a challenge – but it turned out to be more of a challenge than I thought it would be!” he said.

But then, with the help of scientists including Oleg Daugovish, UC Cooperative Extension strawberry and vegetable crop advisor in Ventura County, Hasegawa tried a technique called anaerobic soil disinfestation (ASD). When applied correctly, the multi-step ASD process creates a soil environment that suppresses pathogens and weeds and makes for healthier, more robust crop growth.

“Back in the day, it was really hard to get the plant growing vigorously in organic,” said Hasegawa, owner of Faria Farms in Oxnard. “So we started using the ASD and then you could definitely see that the plant had more vigor and you could grow a bigger, better plant using it.”

Seeing that he could produce yields “in the neighborhood” of those grown in conventional strawberry fields fumigated with synthetic fumigants, Hasegawa was able to expand his original 10 acres of organic strawberries to 50 acres.

“I guess you could say I'm kind of a convert,” he said, noting that he now applies ASD to all his acreage each year in late spring.

Joji Muramoto, UC Cooperative Extension specialist in organic production based at UC Santa Cruz, has been experimenting with ASD since it was first brought to the U.S. from the Netherlands and Japan in the early 2000s. Carol Shennan, a professor in the Department of Environmental Studies at UCSC, and Muramoto were among the first to try the technique in California. They found that ASD successfully controlled an outbreak of Verticillium wilt – caused by the pathogen Verticillium dahliae – at UCSC's small organic farm in 2002.

Since then, Shennan, Muramoto, Daugovish and their colleagues have seen encouraging results at 10 trial sites across the state.

“We demonstrated that ASD can provide comparable yields with fumigants, in side-by-side replicated trials,” Muramoto said.

The strawberry plants in the ASD-treated plot (left) are more robust than those growing in untreated soil. A plastic mulch (typically opaque is used by growers, but clear was used here for research purposes) is crucial as part of the ASD process to improve plant productivity and control weeds. Photo by Oleg Daugovish

ASD promotes host of beneficial changes to soil ecosystem

ASD comprises three basic steps: incorporating a carbon source that is easily digestible by microbes in the soil (traditionally, rice bran has been used), further encouraging fermentation by covering the soil with plastic to limit oxygen supply, and finally adding water through drip irrigation to initiate the “anaerobic” decomposition of the carbon source and maintain the three-week “cooking” process.

The resulting cascade of chemical, microbiological and physical changes to the soil creates an ecosystem that is both conducive to strawberry growth – and inhospitable to pathogens and weeds.

“It's not like a pesticide where you have a mode of action, and thus resulting in ‘A' and ‘B' for you,” Daugovish explained. “There's a sort of cocktail of events that happens in the soil; they all happen interconnectedly.”

Compared to similar fields that did not undergo the process, ASD-applied organic strawberry fields across California have seen yields increase by 60% to 70% – and even doubling in some cases, according to Daugovish.

The UCCE advisor also shared the story of a longtime grower in Ventura County, who came to him with fields in “miserable” condition; they were plagued by one of the world's worst weeds, yellow nutsedge, and infected with charcoal rot, a disease caused by the fungus Macrophomina phaseolina. But after applying rice bran and following the ASD recipe, the grower saw phenomenal results.

“The only complaint he said to me was, ‘Now I have too many berries – we have to have more pickers to pick the berries!'” Daugovish recalled.

Via researchers' meetings, online resources, on-farm demonstration trials and word of mouth from peers, use of ASD by California strawberry growers has grown significantly during the past two decades. Tracking the purchase of rice bran, Muramoto estimated that about 2,500 acres were treated by the ASD-related practices in 2023 – covering roughly half of the 5,200 total acres of organic strawberries in California.

Muramoto directly links the growth of California organic strawberry production – which now comprises about 13% of total strawberry acreage in the state – with the increasing adoption of ASD.

“If you remove the acreage with the applied rice bran over the last 10 years or so, organic strawberry acreage is just flat,” he said.

Applying rice bran provides the easily digestible carbon source that soil microbes feed on. Once covered by plastic mulch, anaerobic conditions develop and microorganisms that prefer such an environment thrive, while pathogenic organisms and germinating weeds are suppressed. Before planting, holes are cut in the plastic to let oxygen back into the soil and encourage the growth of the strawberry plants. Photo by Oleg Daugovish

Within the last decade, acreage of organic strawberries with ASD-related practices increased by 1,640 acres, which is a boon for air quality, human health and long-term soil vitality. According to Muramoto's calculations, that increase in organic acreage translates to a reduction of about 465,000 pounds of fumigant active ingredients that would have been used in growing conventional strawberries.

“There are hundreds of reports of acute illnesses related to fumigation in the record, so it's very important to find alternatives to fumigants,” said Muramoto, citing California Department of Pesticide Regulation documents.

Research continues to make ASD more economical, effective

The popularity of ASD has come at a price, however, for organic strawberry growers.

“There's more organic out there, and I think most of the organic guys are using it, so there's more demand on the rice bran; the price has been steadily going up every year, like everything else,” said Hasegawa, adding that he has been trying to decrease the amount of carbon while maintaining ASD's efficacy.

On top of greater demand from other growers and from beef cattle and dairy producers (who use rice bran as feed), the price also has increased due to higher costs in transporting the material across the state from the Sacramento Valley. So Daugovish and his colleagues – including Peter Henry, a U.S. Department of Agriculture plant pathologist – have been searching for a cheaper alternative.

“We all want an inexpensive, locally available, reliable, easy to use and functional carbon source, which sounds like a big wish list,” Daugovish said.

Carbon sources such as bark, wood chips, or compost are ineffective, as the crucial ASD microorganisms are choosy about their food.

In a field of 'Victor' strawberries, researchers saw a 41% increase in yield using ASD with midds, in comparison to untreated soil. Photo by Oleg Daugovish

“Microbes are just like cows; you can't feed them straight wood; they get pretty angry,” Daugovish explained. “And if you feed them something with too much nitrogen, they can't digest it – they get the runs. Microbes are the same way – you have to have the right proportion of stuff so they feel comfortable doing what they're doing.”

In search of an ideal replacement, researchers tried and ruled out grass clippings, onion waste, glycerin and coffee grounds. Finally, they pivoted to a material with properties very similar to rice bran: wheat bran, in the form of wheat middlings (also called midds, a byproduct of flour milling) and dried distillers' grain (DDG, a byproduct of ethanol extraction).

After field experiments in Santa Paula, the UC and USDA researchers found that midds and DDG were just as effective at controlling soilborne pathogens and weeds as rice brain – but at 25% to 30% less cost. Their results were published last year in the journal Agronomy.

“Not surprisingly, the wheat bran has worked almost exactly the same as rice bran,” Daugovish said.

He and Muramoto are now conducting trials with wheat bran at commercial fields, and the initial results are promising. Daugovish said the grower at one site in Ventura County has seen a 90% reduction in Macrophomina phaseolina, the causal pathogen of charcoal rot, in the soil – and an 80% to 90% drop in yellow nutsedge germination. They are waiting for final yield numbers after the coming summer.

While ASD has been beneficial to organic productivity and soil health, both Daugovish and Muramoto acknowledged specific limitations in suppressing the “big three” strawberry diseases: Verticillium wilt, Fusarium wilt and charcoal rot. In coastal areas with cooler soil temperatures, for example, ASD can actually exacerbate the latter two diseases, as the fungal pathogens feed on the rice bran.

“We know it works at warmer temperatures, but, practically, it's hard to do in coastal California,” Muramoto said. “It would be nice if we can find a way to suppress Fusarium wilt at a lower temperature, but we don't have it right now.”

That's why researchers emphasize that ASD is not a “silver bullet.” It's just one tool in the organic toolbox, which includes careful crop rotation, disease-resistant strawberry varieties and better diagnostic tests that help growers pinpoint outbreaks and make the application of various methods more targeted and more efficient.

And scientists will continue to optimize ASD to make it more effective and economical for growers in the different strawberry regions of California – from the Central Coast to the Oxnard Plain.

“We know it can work really well; it's just finding the most sustainable way to do this in our region,” Daugovish said. “We've got to just have an open mind and keep trying.”

$1.7M granted for climate-smart planning led by UC ANR scientists

Cover crop from a UCCE led research project focused on adapting to climate change using smart land management practices. Photo courtesy of Cristina Murillo-Barrick.

In California, natural and working lands make up 95 million acres of the state and play a vital role in building resilience to the impacts of climate change. University of California Agriculture and Natural Resources was awarded $1.7 million for the California Next Generation and Equitable Climate Action Plan, as part of the state's Natural and Working Lands Climate Smart Strategy and California's 30x30 Initiative, an effort to conserve 30% of the state's lands and coastal waters by 2030.

Natural and working lands include both unmanaged and managed areas actively used for agriculture, forestry or production purposes.

Chandra Richards, UC Cooperative Extension agricultural land acquisitions academic coordinator for Southern California, and Cristina Murillo-Barrick, UCCE's Black, Indigenous and People of Color community development advisor for the Bay Area, are leading the California Next Generation and Equitable Climate Action Plan project.

To build capacity and technical assistance for climate-smart action planning, Richards and Murillo-Barrick will use the Climate Smart Land Management Program funding, awarded through the California Department of Conservation, to focus on two of the most pressing climate action issues: equitable land access and land management diversification.

According to the 2022 U.S. Department of Agriculture census, demographic data indicates that California agricultural land ownership and production is concentrated within an aging and mostly White demographic. However, research suggests diverse management practices promote healthy landscapes. This has been shown to benefit the environment, human health and climate resilience in multiple ways.

For this reason, this project centers on “historically underrepresented communities,” a term that includes California Native American Tribes, communities of color, landless farmers, immigrant and non-English speaking communities and other agency-designated minority groups (racial, ethnic and non-male groups, socially disadvantaged farmers and ranchers, and California designated severely disadvantaged communities).

Focusing on Southern California, UC Cooperative Extension scientists will identify barriers to land access, management and opportunities to increase land manager diversity. They also will engage historically underrepresented communities in coalition building, capacity assessment and climate action planning.

Within the last few decades, Californians have faced increased ecosystem stressors and decreasing diversity of natural systems. This pattern continues to damage already-vulnerable communities (disproportionately historically underrepresented communities), while also worsening and intensifying climate impacts, including drought, wildfire, flooding and disease. Overcoming these kinds of systemic and structural challenges will require the next generation of land managers to reflect California equitably, while preparing them to take on climate resilience. The project will determine clear solutions and plans that enable long-term, strategic land use and protection.

To do this work, UCCE is collaborating with the Community Alliance with Family Farms (CAFF), California Association of Resource Conservation Districts (CARCD) and the California Bountiful Foundation, all of whom serve as subgrantees and will deepen connections with communities.

Organizations like CARCD have long served as “boots on the ground” personnel and have close relationships with landowners and land managers. “RCDs have been hearing the land equity need for a long time and are actively collaborating with different partners to tackle this pressing issue,” said Qi Zhou, program manager of Justice, Equity, Diversity and Inclusion at CARCD and member of the Strategic Growth Council Land Equity Task Force.

“California RCDs are excited about this project because it will allow major California agriculture and conservation partners to collaboratively develop plans and implement projects centering on equity land access and land management diversification,” Zhou added.

Project lead Richards said $270,000 of the grant will be reserved for new partnerships with organizations in Southern California that have experience with, and strong ties to, historically underserved communities.

UC ANR is collaborating with the California Department of Food and Agriculture as well as California Climate and Agriculture Network (CalCAN), and World Be Well, a Southern California nonprofit.

Tawny Mata, CDFA's director of the Office of Environmental Farming and Innovation, described technical assistance providers as being grounded in their local agricultural communities and recognized their importance to partners in the success of CDFA's incentive programs.

“When we do succeed in reaching historically underserved farmers and ranchers with our grant programs, it is often with the thoughtful support and planning of a technical assistance provider,” Mata said. “I look forward to this project helping us refine our own technical assistance funding programs and bringing technical assistance providers together to network and share best practices for improving land access and promoting climate-smart agriculture.”

“The successes of this project will elevate the voices of historically underrepresented communities, strengthening efforts in these communities to support climate action,” said Richards. Additionally, the project will increase sharing of regional reports, needs assessments and community plans surrounding climate-smart management practices. Finally, it will boost technical assistance for these groups specifically.

To learn more about the  Climate Smart Land Management Program and this year's awardees, visit:

https://www.conservation.ca.gov/index/Pages/News/California-award-8-5-million-climate-action-natural-working-lands.aspx.

REC System Director Haver encourages systemic approach to agriculture

Darren Haver (center) and fellow roundtable participants raise their hands when asked the question, "how many of you work in agriculture?" All photos by Saoimanu Sope.

Agriculture generates $59 billion and employs nearly 400,000 individuals in California. The industry, however, is often threatened by challenges like climate change, land conversion and water scarcity. Motivated to act, Sustain Southern California – an organization associated with UC Irvine Beall Applied Innovation – hosted a roundtable discussion on Feb. 20 featuring subject matter experts including Darren Haver, director of UC Agriculture and Natural Resources' Research and Extension Center System.

During his keynote address, Jose Arriaga, Orange County Agricultural Commissioner, defined sustainability as food and fiber production that does not compromise the ability for future generations to meet their needs. In doing so, he acknowledged the benefit of discussing such timely topics with key players, especially for places where agriculture is not as prevalent as it used to be. 

“Many people don't think of Orange County as a place for agriculture. It's probably because less land is being reserved for agriculture, not like back in the day. And that worries me,” said Arriaga. 

Jose Arriaga (left) and Haver (right) during the Sustain SoCal event hosted at the UC Irvine Beall Applied Innovation Center.

The first roundtable discussion centered on sustainable agriculture, with Haver participating alongside other industry leaders based in Southern California, including A.G. Kawamura of Orange County Produce, Steve Brazeel of Sunterra Produce and Elevated Foods, Anthony Curci of Buttonwood Ranch and Parker Cohn from Performance Resource Management.

In discussing today's generation, Haver said that he has seen a shift over the last few decades away from yield alone, which used to be the most important aspect of production in agriculture. Today, much more attention is dedicated to sustainability – a change that Haver attributes to the younger generation of researchers and plant scientists working in agriculture.

There has also been an emphasis on sustaining the environment while maintaining economic progress. Haver recognized these important elements, but highlighted the social impact of sustainability, too.

“I don't have all the answers, but I do believe that addressing the environmental, economic and social aspects of agriculture is important. I also think that these factors should be addressed systemically rather than in silos,” said Haver.

Southern California agricultural producers, in particular, are responsible for $7.8 billion in gross receipts and nearly 100,000 jobs directly related to agriculture. In Orange County alone, where Haver is based at the South Coast Research and Extension Center, agriculture makes up $86 million of total economic output, with nurseries leading as a top commodity followed by fruit trees, vegetable production and livestock and apiary.

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