Posts Tagged: REC

West Side REC study: A cradle of California regenerative agriculture

In 20-year study, UCCE specialist Mitchell, colleagues, growers advance no-till and cover cropping practices

In the 1990s, long before “regenerative agriculture” was a buzzword and “soil health” became a cause célèbre, a young graduate student named Jeff Mitchell first learned about similar concepts during an agronomy meeting in the Deep South.

Mitchell was astonished to hear a long list of benefits attributed to practices known internationally as “conservation agriculture” – eliminating or reducing tillage, cover cropping and preserving surface residues (the plant debris left after harvest). Potential positive impacts include decreasing dust in the air, saving farmers money on fuel and equipment maintenance, improving soil vitality and water dynamics and a host of other ecosystem services.

“All of these things start adding up and you kind of scratch your head and say, ‘Well, maybe we ought to try some of this,'” recalled Mitchell, who became a University of California Cooperative Extension cropping systems specialist at UC Davis in 1994.

In 1998, Mitchell launched a long-term study of those practices at the West Side Research and Extension Center (REC) in Five Points, Fresno County. “We started this because, way back when I first began my job, nobody was doing this,” he explained. “This was brand-new, uncharted territory for California.”

For the next 20 years, Mitchell and his colleagues studied changes to the soil and ecosystem, learned from their failures and successes, and shared those hard-won lessons with fellow scientists and farmers across the state. A summary of their findings was recently published in the journal California Agriculture.

Conservation agriculture in California: ‘No trivial undertaking'

Mitchell and the Conservation Agriculture Systems Innovation Workgroup – a network established in 1998 comprising farmers, researchers, public agency personnel and members of private entities and environmental groups – started with a virtually blank slate. According to Mitchell, surveys at the beginning of the 21st century found that conservation agriculture practices were used on less than one-half of 1% of annual crop acreage in California.

Although no-till is common in the Midwest and Southeast of the U.S. and across wide swaths of the globe, it was almost unheard of in the Golden State. With the development of irrigation infrastructure in the 1920s, California farmers saw continually phenomenal growth in yield over the last century – and thus had little incentive to deviate from tried-and-true methods that relied on regular tillage.

Nevertheless, intrigued by the potential benefits of conservation agriculture, Mitchell wanted to see which of those practices could be feasibly applied to California cropping systems. During the 20-year study at West Side REC, the researchers grew a rotation of cotton-tomato, followed by a rotation of garbanzo, melons, and sorghum, and finally tomatoes.

But at first, it was a struggle to grow anything at all – as they had to master the basics of how to establish the plants in a no-till, high-residue system.

“This was no trivial undertaking,” Mitchell said. “Early on we struggled – we failed the first couple of years because we didn't know the planting techniques and we had to learn those. There was an upfront, very steep learning curve that we had to manage and overcome.”

Then there was the long wait to see any measurable improvements to soil health indicators, such as the amount carbon in the soil.

“For the first eight years, we didn't see any changes whatsoever,” Mitchell said. “But then they became strikingly different, between the no-till cover crop system and the conventional field without cover crops, and the divergence between those two systems became even starker.”

The two-decade time horizon for the West Side REC study is one major reason why it has been so valuable for growers and scientists alike.

“It's so hard to capture measurable changes in soil health and soil function metrics through research because those changes are really slow,” said Sarah Light, UCCE agronomy farm advisor for Sutter, Yuba and Colusa counties and a co-author of the recent California Agriculture paper. “Often in the course of a three-year grant you don't actually get statistically significant differences.”

Reaching, teaching and learning from farmers

The study site on the west side of the San Joaquin Valley also has been a vital teaching resource. Even though Light works with farmers in the Sacramento Valley, she has conveyed findings from that research with her clientele and uses soil samples from the site to vividly illustrate a significant benefit of conservation agriculture practices.

In one demonstration, she drops soil aggregates – which look like clumps of soil – into two containers of water. One clump, from heavily tilled land, falls apart quickly and the water becomes dark and murky. The other, comprised of soil that has been no-till and cover cropped for 20 years, holds together – a sign of healthy, resilient soil – and the water remains relatively clear.

“It's a really simple demo, but it's very effective because it shows how easily soil aggregates break apart with water – or not,” Light said.

That aggregate stability is a key factor in soil's ability to both move water (infiltration) and hold onto water (retention). Those dynamics are crucial for farmers to avoid ponding in their fields, preserve water for drier months, and generally endure the flood/drought whiplash of climate change.

Over the years, Mitchell has hosted thousands of visitors at the West Side REC study site to showcase the potential benefits of adopting soil-health management practices.

“I don't think I'm exaggerating in saying that this is probably the most-visited agricultural field station project in the history of UC ANR (UC Agriculture and Natural Resources),” he said.

Both the West Side REC – and Mitchell himself – are greatly valued by the local grower community.

“Jeff is a microcosm of the university's applied research on the West Side of the San Joaquin Valley,” said John Diener, who grows almonds, fresh market garlic, canning tomatoes, cotton, masa corn and wheat for production and seed on land adjacent to the field station.

Growers adopt, adapt and adjust practices

Tom Willey, a retired farmer and longtime collaborator with Mitchell, has actively encouraged peers to visit the Five Points site – especially in the early years.

“It was very innovative and there weren't many examples of that anywhere in the state,” Willey said. “So, I helped encourage people to go out there and learn and possibly think about doing similar work on their own farms.”

Willey himself was a pioneer in experimenting with no-till practices in organic vegetable cropping systems.

“As organic farmers, we were probably more tillage dependent than conventional farmers because it was the only method we had for weed control; we weren't able to use herbicides,” Willey said.

Despite early struggles, he persisted in trying different techniques and mechanical means of weeding. And Willey later partnered with a group of progressive vegetable growers and UC and California State University Chico personnel to secure a Conservation Innovation Grant from the Natural Resources Conservation Service to support more on-farm trials and share their experiences.

In the end, however, no-till proved too risky to continue, given the losses they incurred. One tricky issue is nutrient cycling. The organic growers found that after mowing down a cover crop and spreading compost, leaving those nutrients on the surface without incorporating into the soil through more vigorous tilling (or adding synthetic fertilizers, as conventional growers could do) results in lower yields. In the short term, farmers simply did not see yields that could sustain their operation.

“It's very difficult in vegetable systems, and particularly difficult in organic vegetable systems,” Willey said. “I would say a number of us have learned to diminish the over-reliance that we had on tillage, but not to completely eliminate it.”

Cover cropping is also a challenge for some farmers, with certain cover crops making a perfect haven for devastating pests such as lygus bugs and stink bugs, according to Diener.

“We do everything we can to eliminate the host crop from which they come, so why am I going to bring the enemies to my house?” he said. “It's about making enough money to be there next year. You're not going to be there next year with these pests. It's just not a practical management option, in light of our significant pest pressure and disease hosts for our crops of value.”

Instead of planting cover crops, Diener said he opts for mixing in grain crops that can similarly contribute to soil health – while generating revenue at the same time. According to Diener, a longtime collaborator with Mitchell, the best way to adopt conservation agriculture practices is to tailor them to specific localities and each grower's circumstances. And in his corner of the San Joaquin Valley, that means not following the template of the high-precipitation, no-till systems found in the Midwest.

“We've adapted Jeff's principles to our program; it won't look like Iowa to you, which is what everybody comes to expect to see. It ain't how it works, folks,” Diener said. “It's a different methodology. We do those things that fit our environment and that's why that West Side field station is important – because it's our environment.”

Promoting and enhancing soil health, one step at a time

More widespread adoption of soil-health management practices can be driven by a variety of factors. With the rise of drip irrigation in tomatoes, for example, more growers began using no-till or reduced till to minimize disruptions to the delicate driptape in their fields.

And, according to Mitchell, the dramatic increase in no-till practices in dairy silage production – from less than 1% to over 40% – was the result of entrepreneurial efforts by a small but extraordinarily dedicated group from the private sector that worked with farmers, one by one.

Because optimizing these practices requires close and intensive attention – and no small amount of courage and gumption – Mitchell and Light understand that growers might need to take an incremental approach. Even one fewer pass over the field, or cover cropping every other year, can provide some benefit for soil health, Light said.

“The value is that when you can prove the concept, then you can motivate every step of the way,” Light explained. “Jeff is showing the shining light of the goalposts, and that can motivate us to take every challenging step along the way.”

Shannon Cappellazzi, who helped with the data analysis on the recently published California Agriculture paper, agrees that there is value in taking a stepwise approach in building soil health.

Cappellazzi was the lead project scientist on the Soil Health Institute's North American Project to Evaluate Soil Health Measurements, which looked at 124 different long-term soil research sites across the continent – including the Five Points site.

After analyzing 2,000 samples from the various study sites, Cappellazzi said the evidence suggests that layering on each component of a conservation agriculture program – doing no-till, adding cover crops and then integrating livestock, for example – can have additive, cumulative benefits for soil health.

“I think having the data to show the long-term benefit makes people willing to do the short-term change, even if it's a little bit hard for a couple years,” Cappellazzi said.

The research at the West Side REC also produced another key takeaway.

“To me, what really stood out was that for most of the soil health indicators, cover crops had a huge impact. Both the cover crops that had no till – and the cover crops that had standard tillage – had considerably higher carbon and soil health indicator measurements than those without cover crops,” said Cappellazzi. She added that the data also indicated improvements in how the water moved into the soil, and how the soil held that water.

Vital research drives an enduring legacy

Water management and conservation, of course, will be paramount in California's increasingly volatile climate reality. Mitchell's Five Points research – and related studies across the San Joaquin Valley by UC Davis agroecologist Amélie Gaudin and others – contributed data that overturned a long-held belief about winter cover cropping.

“There's a lot of preconceived ideas about cover crop water use,” Mitchell said. “One of the things that we learned was that compared to bare soil water loss in the wintertime, cover crop water loss during that same growing period – from about November through March – tends to be almost a wash.”

That crucial finding provided researchers and soil health advocates with invaluable evidence to preserve the practice as an option for farmers.

“They've needed to go around and give a dog-and-pony show to a lot of Groundwater Sustainability Agencies (GSA) that had been on the brink of banning the growing of cover crops because the perception out there is that they use a lot of water,” said Willey, the retired vegetable grower. “But over the winter months, cover crops don't use a lot of water. In fact, they may not use any net water at all.”

The young researchers who studied cover-crop water use represent another important legacy of the Five Points study site. It has been an experiential training ground for many of the next generation of soil scientists, agronomists and ecologists.

“The number of students who have been trained by and through this study has been really phenomenal,” said Mitchell, noting that they have worked on topics ranging from air quality to soil carbon related to no-till and cover cropping.

Their contributions will be essential in continuing to refine and optimize these practices that are fundamental to conservation agriculture. On Diener's concerns about lygus bugs and stink bugs, for example, Cappellazzi – in her new role as director of research at GO Seed – is studying and breeding cover crops with an eye on characteristics that make for less hospitable habitats for certain pests.

Indeed, while the California Agriculture paper effectively wraps up the 20-year study at Five Points, its lessons will continue to resonate and inspire for years to come.

“This is a step in a long journey,” Light said. “It's a launchpad – this paper might be able to tie a bow on it in terms of the data collection, but in terms of the extension impact, this is really just the beginning.”

And for Willey, the omnipresent climate crisis compels the entire sector to pick up the pace along that journey.

“We've got a lot of pressure now to evolve agriculture very rapidly in response to climate change and I don't think we can sit around and twiddle our thumbs,” he said. “We know the directions we need to be heading – with more natural systems mimicry and less reliance on toxic inputs and synthetic fertilizers – and we need to figure out how to incentivize and support farmers in moving in those directions.”

Understanding cattle grazing personalities may foster sustainable rangelands

Matching herds to landscape can support animal growth and ecological needs

Not all cattle are the same when it comes to grazing. Some like to wander while others prefer to stay close to water and rest areas.

Recognizing those personality differences could help ranchers select herds that best meet grazing needs on rangelands, leading to better animal health and environmental conditions, according to a new paper from the University of California, Davis, published in the journal Applied Animal Behaviour Science.

“Cattle can actually be beneficial for the rangelands,” said lead author Maggie Creamer, who recently earned her Ph.D. in animal behavior at UC Davis. “Vegetation in rangelands actually need these kinds of disturbances like grazing.”

Ranchers can add elements to the rangeland such as water, mineral supplements and fencing to influence where cattle graze, but little research has been done on how those efforts affect individual cows. Considering personalities could save money.

“If you're spending all this money to add a management tool in order to change the distribution of your animals, that's a huge cost to ranchers,” said Creamer. “Thinking about other tools, or selecting certain animals with these grazing traits, might be a better way to optimize the distribution on rangeland rather than spending a bunch of money for something that may ultimately not pan out for all your animals.”

Effects of grazing

Livestock graze on an estimated 56 million acres in California, and healthy rangelands host native vegetation and animals, foster nutrient cycling and support carbon sequestration.

Uneven grazing can degrade water quality, soil health and habitats. Optimizing grazing — including the even spread of cow pies — can improve the ecosystem while also reducing fuel loads for wildfires.

To better understand individual grazing patterns, researchers went to the UC Sierra Foothill Research and Extension Center in Browns Valley and tracked 50 pregnant Angus and Hereford beef cows fitted with GPS collars.

The research

The cattle, which were tracked from June to August over two years, had access to 625 acres of grasslands and treed areas ranging in elevation from 600 to 2,028 feet. In the second year, a new watering site was added at a higher elevation.

Across the two years, the cows showed consistent and distinct grazing patterns even when water sources changed. Age and stage of pregnancy did not affect patterns, though cattle tended to clump near water and rest sites on hotter days.

The cows that ventured into higher elevations and farther from watering sites had more variability in their grazing patterns than those that stayed at lower elevations near water. That suggests it may be harder for non-wanderers to adjust to some landscapes.

“Thinking about the topography of your rangeland and your herd of cows can benefit both the animals and the sustainability of the land,” said Creamer, who next month begins work as a postdoctoral scholar in North Carolina.

Gauging personalities

Keying in on personality type may sound difficult, but the researchers also found some clues as to how to pinpoint the wanderers and homebodies. Unlike cattle at feedlots, the breeding cow population, especially on rangelands in California and other western states, live largely “wild” lives and are rarely handled, save for vaccinations and weaning.

Research due to be published later this year found that paying attention to individual cow reactions during those events can help determine personalities. The cows that appeared more passive during those handling interactions tended to be nomadic.

“We found that you can maybe predict those hill climbers if you kind of look at how they act when the veterinarian or rancher handle them,” said senior author Kristina Horback, an associate professor in the Department of Animal Science at UC Davis.

Informing practices

For ranchers, the findings could be invaluable, said Dan Macon, a livestock and natural resources Cooperative Extension advisor in Placer and Nevada counties for UC Agriculture and Natural Resources.

“Any time we can improve our understanding of cattle behavior, particularly at the individual level, it can improve how we handle livestock and manage the landscape,” he said.

Macon said that during the recent drought, it was hard to get cattle into higher country, but if ranchers could have selected the nomads, it may have saved money in terms of ranch labor and other efforts.

“If you ask a rancher who has been attentive to their cattle over many years, they know the personalities,” Macon said.

For Creamer and Horback, the research opens new doors into understanding herd behavior and dynamics, one that could be a cheaper alternative to high-tech solutions.

“Animal science tends to look overlook the mind of the animal when searching for solutions to challenges,” Horback said. “It's always been a direct line to genetics for immunity or nutrition, but nothing about the mind of the animal. And that's such a loss. There's so much we can learn from behavior in the end.”

The Russell L. Rustici Rangeland and Cattle Research Endowment supported the research.

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

From Sharqia to Rome to Fresno: Renowned irrigation expert comes to UC ANR

Atef Swelam begins as director of Kearney and West Side Research and Extension Centers

In the fields around the Egyptian city of Minya Al-Qamh, “port of wheat” in Arabic, a boy rubbed his eyes wearily as he helped his father irrigate their crops at 2 a.m. – when they could access the scarce water that reached their farm, located at the tail end of the canal. The family, which had been farming the land around the village of Sharqia for many generations, barely had enough water to sustain their wheat and vegetables.

Swatting in the darkness at the incessantly biting mosquitoes, a young Atef Swelam made a vow.

“I said: ‘I will do my best to not let anyone suffer like I have suffered, like my father suffered – I will help to improve the lives of others,'” recalled Swelam, who went on to become an irrigation engineer improving water-use efficiency.

During the World Food Forum (Oct. 16-20), Swelam was recognized by the United Nations' Food and Agriculture Organization as a “Water and Food Hero” for developing irrigation techniques that save water and boost yields across the Nile Delta and beyond.

Swelam started on Aug. 10 as director of both the Kearney Agricultural Research and Extension Center in Parlier and the West Side REC in Five Points. Both facilities are part of a network of centers operated by University of California Agriculture and Natural Resources.

“Our organization, and more importantly the communities we serve in the Central Valley and across California, are so fortunate that Atef has joined our team,” said Brent Hales, UC ANR associate vice president for research and Cooperative Extension. “He brings not only a record of truly impactful research and innovation but a genuine passion for learning the needs of people, working with them and developing collaborative, science-based solutions.”

Making a difference in the lives of people

After earning his master's degree in land and water management from the Mediterranean Agronomic Institute of Bari in Italy, Swelam returned to Egypt for his Ph.D. in agricultural engineering at Zagazig University. There, he advanced to become a professor of irrigation and drainage engineering in 2019; he was also a senior scientist and research team leader with the International Center for Agricultural Research in the Dry Areas (CGIAR-ICARDA). Most recently, Swelam was the agricultural research officer of the U.N.-FAO's Office of Innovation in Rome.

Swelam explained that the mandate, function, mission and vision of UC ANR's research and extension network – and its strong reputation for making an impact through co-creation with clientele – attracted him to this position in California.

“I'm always looking to make a difference on the ground and in the lives of people,” he said. “If you look at the locations where all RECs are located, they are inside the communities themselves, and in the heart of the farming system.”

Swinging between Kearney and West Side RECs, Swelam said he feels he works in an empowering environment, created and supported by the leadership as well as by the staff at both centers – “a dynamic is which hard to find elsewhere.”

Darren Haver, recently named director of the statewide system of RECs, said he will work with Swelam to explore ways to secure the resources that the Kearney and West Side teams need.

“Atef brings a wealth of experience in conducting research as well as working to elevate and amplify the research and outreach of others,” said Haver, formerly the director of South Coast REC in Irvine. “He clearly is committed to making a difference locally, nationally and globally and we are excited to support him as his vision for these two RECs evolves.”

Being a farmer and a scientist, Swelam feels he is on the same wavelength with both of the RECs' clientele groups – researchers and growers. In his first months on the job, Swelam said he will get to know the needs of the grower community and the researchers at the RECs.

“What I like most about this job is that the REC system, with its research for development approach, supports the scientists, who are in turn supporting the farmers and communities that are on the front line in achieving food and nutrition security,” he explained.

When tailoring solutions to meet local conditions, Swelam added that it's essential that community members are involved so they feel a sense of ownership and are committed to sustaining its impact beyond the time limits of a research or extension project.

Innovative irrigation technique used worldwide

A prominent example of Swelam's community-based work is his long-term mechanized raised-bed (MRB) irrigation program, the technology for which he has garnered numerous international honors.

While he was a researcher at the CGIAR-ICARDA, Swelam led several projects between 2010 and 2020 to study new soil and water practices at farm level. Through a project at his home village, he developed a cost-effective, small-scale machine to enable growing wheat on raised beds. This was in contrast to flat flooded land – the traditional, labor- and resource-intensive method that produced irrigation inefficiencies and caused shortages for downstream farmers like his father, Haj Ibrahim.

With MRB, precisely placed trenches between the raised beds would hold exactly the amount of water the adjacent crops need and thus leave more water for all. And while the technique seemed promising, Swelam had to convince skeptical farmers to adopt the practices – including his neighbors and his own father.

“He was very resistant to me in the beginning, because this was the first time ever in Egypt using raised beds for wheat cultivation…he even tried to convince people not to follow me,” Swelam said, with a chuckle.

So father and son divided their fields, with one half planted and irrigated using traditional methods, and the other using the raised-bed approach. Gradually, as MRB began to prove its worth, Haj Ibrahim warmed to the technology and became an active collaborator on the research – even helping the scientist when he was puzzled by experiment results.

“My father was my mobile library,” Swelam said. “He was illiterate – he had never been in a school – but his thinking and knowledge about the real agriculture and farming system were much better than those of a professor like me!”

After the initial research trials produced successes in his village and the larger governorate (a political division within Egypt), the technique was replicated in other governorates across the country – which then attracted the attention of other nations and international organizations.

Overall, Swelam said, the technology helped the growers reduce applied water by 25% and cut farming costs by 25%, while boosting fertilizer use efficiency by 30% and increasing yield by 25%.

Today, MRB is applied by more than 2 million farmers in the Middle East and North Africa to a variety of crops and is recognized as a good agricultural practice by the U.N. Food and Agriculture Organization.

“The biggest recognition and reward for me out of this impactful innovation is seeing the smiles on the faces of farmers,” Swelam said.

Spreading best practices across San Joaquin Valley and beyond

Swelam said he hopes to see similarly positive results for farmers here in California with a wide range of innovations. He and other researchers at Kearney and West Side RECs will continue to make sure that the science and knowledge generated at the centers reach farmers. He added that partnering with local growers to optimize their on-farm practices is crucial on a host of issues, from pest management to water conservation.

“Whatever we do to improve supply management at system level, if the water is not used efficiently at farm level, then we lose everything we had achieved at that macro level,” he explained.

Swelam added that investing intensive time and effort in developing practical, cost-effective solutions will pay off in the long run as they become naturally adopted across the grower community.

“Farmers are very clever and skilled with their farming systems,” he said. “When they see or get benefits from something, they promote it among themselves.”

Swelam's father was one example. After leading the resistance against mechanized raised beds initially, he eventually became its most vocal proponent.

“He became the biggest promoter for this technology; he even promoted it on local and international TV and radio programs,” Swelam said. “I was proud of my father.”

Haj Ibrahim died in 2017 and Swelam continues to pay tribute to his father through his life's work on research and extension – inspired by their long struggles to bring water to their crops, and the shared triumph of their new techniques.

New avocado proves tasty, safer to harvest at UC ANR Research and Extension Centers

A new avocado, one that complements the widely known ‘Hass,' will hit the world market soon. The ‘Luna UCR' variety (trademarked and patent pending) has several characteristics that should be of interest to both growers and consumers, said Mary Lu Arpaia, University of California Cooperative Extension subtropical horticulture specialist based at UC Riverside.

From the grower perspective, the tree is about half the size of the leading variety while producing approximately the same yield per tree as ‘Hass,' meaning that growers could plant more trees per acre, therefore increasing yield. It also makes harvesting easier and safer.

Another advantage is the flowering behavior of the tree. Avocado trees are categorized into either Type A or Type B flower types. It is generally accepted that you need both flower types in a planting to maximize productivity. The ‘Hass' is an “A” flower type and ‘Luna UCR' is a Type “B.”

This is a potential boost for growers since the current varieties that are “B” flower types ripen green and generally receive lower prices for the grower. Similar to ‘Hass,' however, the ‘Luna UCR' colors as it ripens.

“Hopefully, it will receive similar returns to the ‘Hass' once it is an established variety,” Arpaia added.

Fruit breeding is a long-term process that she has navigated by building upon the work of her predecessors. Of course, Arpaia has had strong support from colleagues as well, including Eric Focht, a UC Riverside staff researcher and co-inventor of ‘Luna UCR.'

“We had been looking at ‘Luna UCR' for some time and it was always a very good eating fruit,” Focht said. “After the 2003 release of ‘GEM' (registered and patented as ‘3-29-5', 2003) and ‘Harvest' (patented as ‘N4(-)5', 2003) varieties, ‘Luna UCR' was always the top contender for a next release due to the small, narrow growth habit, “B” flower type and the fruit quality.”

“It's a very nice-looking fruit as well and seemed to be a pretty consistent bearer from year to year.”

A glimpse at how it all started

In spring 1996, Arpaia took over the UC Avocado Breeding Program following Guy Witney who led the program from 1992 to 1995, and Bob Bergh whose initial efforts in the 1950s were foundational in the inception of ‘Luna UCR.'

Arpaia recalls the first trials in the early 2000s of ‘Luna UCR,' which were tested alongside other promising selections from the Bergh program. “There were a lot of varieties that didn't perform well, some of which had poor storage life, an important trait that we need if we are going to get the fruit to consumers across the country,” said Arpaia.

The original seed and selection were planted at the Bob Lamb Ranch in Camarillo, and originally advanced trials of the ‘Luna UCR' variety were planted in four locations: UC Lindcove Research and Extension Center in Tulare County, UC South Coast Research and Extension Center in Orange County, a privately owned farm in San Diego County and another one in Ventura County.

The RECs are among the nine hubs operated by UC Agriculture and Natural Resources to support research and educate the public on regional agricultural and natural resource challenges. 

ANR Research and Extension Centers become vital

Unfortunately, the 2017 Thomas Fire burned the avocado trees in Ventura, said Arpaia. After a change in management, the trial located in San Diego County was also terminated, leaving the two trials at Lindcove and South Coast REC. 

“South Coast REC has a long history of supporting research and extension activities of high value crops important to California, including avocados,” said Darren Haver, director of the South Coast REC, which was often used to show growers the new varieties that were being developed.

“Many of the REC staff have worked with the avocado-breeding program researchers for more than two decades and continue to work closely with them to ensure the success of new avocado varieties, including ‘Luna UCR',” he added.

In addition to the support provided by South Coast and Lindcove RECs, Arpaia said that UC Kearney Agricultural Research and Extension Center in Fresno County – another UC ANR facility – made it possible for her team to conduct critical postharvest and sensory research, and consumer testing of the fruit, which included up to six-week trials of fruit ratings for storage life and taste.

“UC ANR has played an important role in our ability to not only identify ‘Luna UCR', but in preparing it for the world market, too,” she said.

Preparing to share with the world 

Since 2015, Focht had been collecting data for the patent application. Now that he and Arpaia have successfully patented and trademarked ‘Luna UCR,' they are preparing to expand production by engaging interested growers with the commercial partner, Green Motion who is based in Spain.

“Green Motion contracted for 1,000 trees to be generated by Brokaw Nursery and those trees are currently being distributed, with earliest field plantings likely taking place in fall,” explained Focht.

Focht also said that Mission Produce, based in Oxnard, CA has contracted to graft over a small number of “B” flower type pollinizer trees to the new ‘Luna UCR' variety, possibly making way for a small number of avocados to be available the following year. 

Once planted, the avocado trees will come into “full” production in about five years.

To read this story in Spanish, visit: https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=58991

Winter atmospheric rivers gave pathogens, diseases path to infect crops

Outbreaks similar to El Niño-influenced issues of the 1990s

The wave of atmospheric rivers that swept across the state this winter has created the right conditions for plant pathogens that haven't been seen for decades in California. University of California, Davis, plant pathologist Florent “Flo” Trouillas is getting more calls from growers and farm advisors concerned about potential crop damage.

“Generally, whenever you have rain events, you're going to have problems,” said Trouillas, a Cooperative Extension specialist who is based at the Kearney Agricultural Research and Extension Center in Parlier. “In wet years we get really busy because most pathogens need and like water.”

Trouillas is like a disease detective. He splits his time between the field and the lab, working to diagnose pathogens, diseases and other ailments that strike fruit and nut crops such as almonds, cherries, olives and pistachios.

On a recent visit to an almond orchard near Fresno, Trouillas joined Mae Culumber, a nut crops farm advisor for UC Cooperative Extension Fresno County. A few weeks earlier, the two had walked the orchard, taking note of the base of some trees that had gumming — a thick, jelly-looking substance indicating a pathogen had taken hold.

“A lot of what Florent is doing is trying to assess patterns on a landscape,” Culumber said. “Sometimes things may look like they are one thing, but it could be another problem.”

When the two returned weeks later, the amber-colored gumming had moved into the canopy, looking like gumballs stuck to branches, some of which were already dead. “It's getting out of control from before,” Trouillas says. “This branch was killed. This is widespread.”

From the field to the lab

Lab testing confirmed what Trouillas believed was the culprit: Phytophthora syringae, a pathogen that can affect almond crops but is rarely seen in California. If it is found, generally the site of infection are wounds caused by pruning, but that is not the case here, where the infection began in the canopy at twigs, or small branches.

It is a threat to a key crop, which according to the California Department of Food and Agriculture, generates $5 billion annually. The last time Phytophthora syringae hit California was in the 1990s after a series of El Niño-influenced storms. Trouillas, who has a photographic memory, remembered reading about it in an old manual.

“It's rare for California and one that we see mostly following atmospheric rivers,” he says.

“The disease will only happen following these extremely wet winters.”

Phytophthora is soilborne, mostly found in tree roots, and doesn't generally spread up into branches. But the intense storms created the right conditions for the pathogen to “swim” up trunks as winds blew spores into the air and rain dropped them back down into the canopy, Trouillas said.

Some of the trees in this orchard will die; others can be saved by pruning infected branches and applying a recommended fungicide, he said.

Identification, diagnosis, education

Trouillas is one of more than 50 Cooperative Extension specialists at UC Davis and each is charged with identifying problems and developing solutions for those issues in support of agriculture, the ecosystem and communities throughout the state.

In his role, Trouillas focuses not only on pathology and research but also on educating growers, nursery staff, pest control advisers and others in agriculture about ways to manage potential threats and how to prevent crop damage.

“His role is very crucial,” said Mohammad Yaghmour, an orchard systems advisor for UC Cooperative Extension Kern County. “He's not only on this mission to educate growers but he's also a source of education for us.”

Trouillas typically conducts one or two site visits a week, usually after a farm advisor reaches out about a problem they can't solve on their own.

“This allows us to be at the forefront of disease detections in California,” he said.

He likens these visits to house calls a doctor would make, only to fields instead. And one of those calls recently took him to a cherry orchard in Lodi.

“These guys help me quite a bit,” said Andrew Vignolo, a pest control adviser with Wilbur-Ellis who asked for a consult. “I bug them a lot.”

The visit starts like any consult in a doctor's office, only the questions come fast as they walk around the Lodi orchard where branches are dying, there is gumming and the trees appear stressed. Some look to be sunburned from exposure. Old pruning wounds show cankers, indicating that past disease treatments didn't get rid of whatever was affecting the trees.

Trouillas asks about the cultivar of the trees because some varieties are more susceptible to pests or diseases. He focuses on stress because that opens the door to disease.

Do they prune in the dormant winter months or in summer when pathogens are more prevalent? Does the soil get tested? How old are the trees? What about nutrition?

“I'm trying to figure out how they got infected so bad,” Trouillas said, walking the orchard. “Bacterial canker is a very mysterious disease.”

He thinks it might be a bacterial canker disease and shaves some bark to take to the lab for testing. He wants to come back next winter to take some samples to see where the pathogen is overwintering.

“We'll know in a few weeks if we have a fighting chance,” Vignolo said.

Be it Lodi, Fresno or elsewhere in the state, Trouillas focuses on local conditions. But what is learned in one field can be passed on to others, providing early warnings or advice for those in similar situations. “All these efforts at collaboration, from the field, to the lab, going through research projects, there's only one goal here — to help the farmers of California.”

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