Posts Tagged: Natural Resources

Unique conditions in Modoc County drive organic agriculture adaptations

UC Organic Agriculture Institute visits area to hear innovations, needs of local producers

Modoc County, home to 8,500 people and tucked in the remote northeastern corner of California, has been a leader in advancing organic agriculture through its significant ranching and agronomic crop production, namely of potatoes and hay.

In fact, Modoc County is California's number one county for organic beef cattle production (119,782 acres in 2022), and consistently in the top five counties for total harvested certified organic acres in the state, according to the most recent California Department of Food and Agriculture statistics.

“Modoc County farmers and ranchers in many ways exemplify the values of organic agriculture, adapting and tailoring their operations to the contexts of the unique landscapes we live in,” said Laurie Wayne, University of California Cooperative Extension nutrition, community health and food systems advisor for Modoc, Siskiyou and Lassen counties.

This past summer, Wayne and Rob Wilson – UCCE farm advisor and director of the Intermountain Research and Extension Center operated by UC Agriculture and Natural Resources – shared their insights with a visiting team from the UC Organic Agriculture Institute.

Established in 2020 as an institute under UC ANR, OAI was created to develop research, extension and education support for certified, transitioning and aspiring organic farmers and ranchers across California. The OAI team has been visiting different regions to better understand the unique conditions of organic agriculture in those areas.

“These tours are our chance to build relationships with local farmers, partner organizations and colleagues and see how organic agriculture has grown and developed in that specific region,” said Houston Wilson, OAI director. “We also get to learn directly from farmers and ranchers about how regional contexts and community goals influence organic agriculture in their area.”

Modoc County's geography, climate spur adaptive strategies

Wayne, who previously operated a farm in Modoc County and also co-founded the Surprise Valley Saturday Farmer's Market and Modoc Harvest Food Hub, was the perfect person to introduce the OAI team to local agricultural producers.

“I hoped to show our visitors just a glimpse at the many lessons I've learned and inspiration I've gained from the agriculture community in Modoc,” Wayne said.

A common theme across Modoc County is the use of innovative and place-based strategies to farm within diverse ecosystems. For example, extensive rotational grazing is well-suited to the region's vast sage steppes, perennial grasslands and sagebrush ecosystems.

333 Ranch – a third-generation ranch in Lake City owned and operated by Sophie Sheppard, Lynn Nardella, and their son, Jason Diven – raises rotationally grazed beef cattle and calves, hogs and Icelandic sheep and grows organically managed vegetables.

Half of 333 Ranch is under conservation easement to preserve natural resources and wildlife. Their land stewardship practices include working with the Savory Institute – a nonprofit that supports the health of grasslands and the livelihoods of people on those landscapes – on ecological grazing techniques. They also partner with the USDA Natural Resources Conservation Service to convert barbed wire fencing into high tensile fencing for riparian habitat restoration. Sheppard reported that one year after the fence conversion, the ranchers saw nesting Greater Sandhill Cranes and beavers building dams in their creek.

Leah Larsen of Bidwell Canyon Farm in Fort Bidwell said she learned high tunnel production from Sheppard at 333 Ranch and others in the area. High tunnels allow farmers to extend their growing seasons to accommodate diverse crop rotations and opportunities for local food production.

Larsen – who grows vegetables, fruit trees and berries on 1.5 acres (including in two high tunnels) – also raises milk goats and chickens, maintains grazing pasture and operates a farmstay rental. With 11 years of experience farming in Modoc's high desert climate, Larsen offers mentorship to other growers in the region and shares information through channels such as the region's high tunnel Facebook group.

Canyon Creek Ranch in Alturas uses prescribed burns to manage invasive tree species in the sagebrush steppe. Richard (Dick) Mackey and his family operate 3,300 certified organic acres, with 350 head of cattle and 500 acres of hay, pasture and alfalfa. In addition to organic certification, Canyon Creek Ranch is also Ecological Outcome Verification (EOV)-certified; EOV is a program of the Savory Institute that gathers ecosystem data to verify that ranching practices are regenerating the land.

Mackey, whose family has owned and operated the ranch since 1946, brought the OAI team to an area of their property that is managed with fire, demonstrating how their agroecological stewardship has improved the land and suppressed invasive species.

“It was remarkable to see the difference ecological management such as prescribed burning and targeted grazing can make in promoting both healthy ecosystems and more productive organic agricultural systems,” said Krista Marshall, OAI policy and partnerships coordinator. “I feel incredibly grateful to have gotten the opportunity to learn from the innovative and thoughtful farmers and ranchers across Modoc County about how we can accomplish multiple goals in agroecosystems.”

Another example of ecological and agricultural goals being met simultaneously can be found at Tule Lake, where rotations incorporate a wetland wildlife refuge and crop production. Rob Wilson noted that this “Walking Wetlands” program has benefited organic producers with good pest and disease control from the flooded years in the rotation.

“The Walking Wetlands program is a great example of public and private land managers working together to meet land use objectives,” said Wilson, the UCCE farm advisor. “The program results in hundreds of acres of restored marshland habitat for migrating waterfowl each year, while providing organic potato and small grain growers with productive farmland largely devoid of soilborne pathogens and nematode pests.” 

Farm labor support, meat processing infrastructure investment needed in region

All ranchers on the OAI tour commented on the lack of U.S. Department of Agriculture-accredited meat processors in the county. Ranchers explained that they must transport animals hundreds of miles to other counties or across state lines to access facilities.

Jon and Kelsey Arreche of Cow Creek Meat, Inc. at Arreche Farms in Cedarville said that the year-long wait lists for processing complicates planning.

The Arreches manage 1,300 acres of pasture, alfalfa, wheat, barley and hay and raise 110 grass-fed and grass-fed/grain-finished beef cattle, as well as hogs, lamb and poultry. Cow Creek Meat was certified organic for 12 years and continues to farm organically despite not pursuing certification currently.

Jon Arreche commented that prices for commodities like alfalfa are not stable but rather fluctuate between organic and non-organic markets, with some years offering a better premium than others. He said that they may pursue certification again in the future.

“Greater investment in processing infrastructure and the need for organic market development are two concerns we heard consistently on the tour,” said Shriya Rangarajan, a postdoctoral researcher with OAI. “We have to ensure the long-term economic viability for these local ranchers.”

The remoteness of Modoc County also has contributed to labor challenges for farmers and ranchers across the region. Some growers have pursued hosting farm apprenticeships or internships, through programs like World Wide Opportunities on Organic Farms (WWOOF) or through direct hire.

Bidwell Canyon Farm has a farm internship program, which helps with labor on the farm and also contributes to mentoring and teaching the next generation of farmers. There was widespread interest in developing training programs, akin to Rogue Farm Corps in Oregon, to link beginning farmer apprentices with host mentor farmers.

“Hands-on experience working on farms is the best way to inspire and train the next generation of farmers,” said Marshall. “Farmers in Modoc are already creating these types of apprenticeship programs on their farms, so network and capacity building to support these efforts would benefit the agricultural community.”

Markets often dictate whether organic certification is useful

The number of certified organic farms and ranches in Modoc County declined from 34 in 2018 to 19 in 2022, according to CDFA statistics. The OAI visitors learned from growers in the region that markets often dictated if formal certification made business sense for their organically managed operations.

Kay and Erik Antunez de Mayolo grow vegetables, herbs, berries and natural dye plants on a quarter-acre and heritage apples, peaches and other fruit trees on an additional three acres at Oz Garden in Eagleville. They manage their farm organically, but are not certified. Kay Antunez de Mayolo, who markets produce and value-added goods at the Surprise Valley Farmers Market in Cedarville and the Alturas Farmers Market, also contributes to the Modoc Harvest Food Hub.

Most Modoc growers, certified or not, know their customers through direct sales and build trust around the integrity of their operations. Many farmers and ranchers ultimately don't see the financial benefit of certification because of these direct relationships with their customers – especially given the certification cost and administrative effort required.

While cost-share programs for organic certification fees exist (such as the USDA Organic Certification Cost Share Program), applying for and maintaining certification status takes valuable time – in addition to direct financial outlay.

Modoc growers contribute to conserving plant diversity

The lively local food and farming community in Modoc County also includes smaller-scale vegetable and fruit farms; the State Organic Program reported 1,281 organic vegetable acres in Modoc in 2023. Modoc fruit and vegetable growers are conserving heritage crops on farm and preserving unique plant varieties while producing food for the community.

At Oz Garden, the apple trees are over 125 years old. Through the Modoc Harvest Heritage Fruit Tree Project, Kay Antunez de Mayolo and others work to identify these cultivars through research and DNA fingerprinting at the UC Davis Genetics Lab. Oz Garden grows diverse plant varieties, including the “Old Fashioned Surprise Valley Tomato,” a locally adapted beefsteak variety stewarded by Modoc resident June Perry.

Bidwell Canyon Farm introduced the OAI team to honeyberries, also known as Haskap berries, which look like an elongated blueberry but have a distinct honeyed flavor and produce well in Modoc County.

“That bit of honeyberry was symbolic of the entire tour – a small but memorable taste of the richness and diversity of Modoc County organic agriculture,” Marshall said. “We are so grateful to Laurie and all the farmers and ranchers for taking the time to share their experiences and feedback with us.”

Foundation created to energize community support for UC ANR mission

Board of Directors to promote philanthropy through advocacy and fundraising in support of agriculture, natural resources and community health

The new University of California Agriculture and Natural Resources Foundation has been established to advance UC ANR's essential research and extension mission.

The foundation – to be incorporated as a 501(c)(3) organization following approval by UC President Michael Drake in October – will support programs that promote California's agriculture and food systems; natural ecosystems and working landscapes; and healthy and thriving communities.

“The establishment of this foundation could not have come at a better time, as it will inspire the vital resources and energy we need to meet the pressing challenges we pinpointed in our recently released Strategic Vision 2040,” said Glenda Humiston, UC vice president for agriculture and natural resources.

Modeled after similar entities at UC campuses, the UC ANR Foundation will be guided by a volunteer Board of Directors. Representing a variety of regions and communities across California, the directors collectively bring years of experience in the agriculture, natural resources, government, academic and nonprofit sectors.

“By tapping into the board's connections, relationships and knowledge of our work and its impact, UC ANR is well-positioned to undertake significant and truly transformative fundraising initiatives and campaigns,” said Greg Gibbs, executive director of UC ANR Development Services.

The Board currently comprises eight community leaders and three ex officio members:

Don Bransford
Owner and Operator
Bransford Farms

Tom Delfino
Sr. Principal
S.S. Papadopulos & Associates

Bill Frost
UC Cooperative Extension Advisor Emeritus and former Associate Vice President
UC ANR

Anne Haddix
Co-President, Board of Directors
UC Master Gardeners of Sonoma County (Volunteer)

Corinne Martinez, Board Chair
President and Chief Operations Officer
Berryessa Gap Vineyards

Soapy Mulholland
Principal
Sopac & Associates LLC

Sharon Nance
President
NTAPROBLM LLC Inc.

Stephen Reid
Head Gardener of the Rose Garden
The Huntington Library and Botanic Gardens

Ex Officio Members

Greg Gibbs, Board Secretary
Executive Director, Development Services
UC ANR

Glenda Humiston
Vice President
UC ANR

Tu Tran, Board Treasurer
Associate Vice President
UC ANR

“We are grateful to the members of the new board for their leadership, expertise and passion for our mission, and we're thankful to the many donors – past, present and future – who generously support our work to improve lives all across California,” Humiston said.

History of philanthropic support empowered creation of foundation

It has been that outpouring of support – channeled by Gibbs' fundraising team – that enabled the establishment of the UC ANR Foundation. Gibbs was part of a nascent development team created just seven years ago, in 2017, to increase private funding from individuals, foundations, companies and agricultural commodities groups.

Within that time, the Development Services team has raised crucial funds for a wide range of impactful programs and projects. For example, philanthropic support is fueling efforts to cultivate workforce development in agriculture and related fields in Orange County, drive innovations in the “circular bioeconomy” within the San Joaquin Valley, strengthen wildfire resiliency in communities across the foothills of the Sierra Nevada, and propel leading-edge research to benefit growers of citrus, grapes and other valuable commodities.

“People are seeing the true impact of UC ANR, and I think this foundation board is a testament to that,” Gibbs said. “It's a validation of all the work that's been done over the last seven years.”

In 2023, a Vice President's Cabinet began laying the groundwork for the foundation by establishing its bylaws and structure. That group comprised several current board members, as well as Andrea Ambrose, UC ANR director of advancement; Adina Merenlender, professor of Cooperative Extension in conservation science; and Kerry Tucker, chief strategic counsel at Nuffer, Smith, Tucker.

Then, presented with UC ANR's track record of robust fundraising and measurable impacts, UC President Drake approved the incorporation of the new nonprofit foundation on Oct. 2. The foundation will begin work with UC ANR leadership and staff in early 2025 to develop short- and long-term fundraising plans.

For the public, there is an immediate opportunity to support UC ANR's work – Giving Tuesday. From midnight to midnight on Tuesday, Dec. 3, visit give.ucanr.edu to donate and participate in a global online giving event.

“Just as UC ANR programs significantly improve lives in California and across the nation and world, our donors substantively improve those programs,” Gibbs said. “They believe in what we do, and they make our research and extension activities better in every sense – more impactful, more accessible and more sustainable.”

For more information on the UC ANR Foundation and opportunities to contribute, contact Greg Gibbs at glgibbs@ucanr.edu.

Good fire is back at the Hopland Research and Extension Center

Fire has been part of indigenous stewardship in California since time immemorial. These fire practices were deeply connected to cultural traditions, food ways, and enhanced the resilience of landscapes. Using fire for research and land management at the UC ANR Hopland Research and Extension Center (HREC) dates back to the early 1950s and fire was used as an effective tool for maintaining the health of the landscape for many years. However, the regulations and paperwork permitting controlled burns became increasingly restrictive after the catastrophic wildfires of 2017. 

Thanks to three years of perseverance by John Bailey, HREC director, and with help from trained UC ANR advisors and staff, we were able to execute a research burn once again, instead of relying on the more restrictive CalFire Vegetation Management Plan process. By carefully reintroducing fire, a tool essential for rangeland and oak woodland stewardship, we want to be able to use good fire for research and to recover biodiversity and make the landscape more climate resilient.

On Nov. 8, 2024, HREC successfully conducted a prescribed burn as part of ongoing research to advance the restoration of a unique perennial wetland. This prescribed burn is part of a larger initiative to enhance native biodiversity and control invasive species. Fire was used as a natural disturbance to open up the dense Tule stands surrounding the pond to create a habitat mosaic with a diversity of plant species and habitat structure for native frogs and other pond life. 

The burn was led by UCANR staff and academics, including Jeff Stackhouse, UC Cooperative Extension natural resource advisor, and Mike Jones, UCCE forestry advisor, whose leadership ensured its successful execution. We also had significant community participation from members of theHopland Band ofPomo Indians, including their Environmental Protection Agency director, as well as Grizzly Corps members, researchers and volunteers.

This event provided an opportunity for the diverse group to learn about controlled burns, engage in fire safety education, and explore how such practices contribute to ecological resilience. By involving community members in the process, the event not only restored habitat but also fostered a deeper understanding of fire's role in ecosystem health and stewardship.

HREC plans to work with UC ANR leadership and the UC ANR Fire Network to establish clear policies for conducting regular burns for research, stewardship and extension. Additionally, HREC will continue partnering with CalFire, leveraging their capacity for larger-scale projects, ensuring a variety of pathways are available for safely conducting prescribed fire and to strengthen the UC-CalFire relationship for better land stewardship outcomes statewide.

 

Virtual fencing ‘game-changer’ for ranchers grazing cattle

Tech can save ranchers time and benefit animals and land, becoming more viable

After the Caldor Fire destroyed seven miles of fencing on their cattle ranch in 2021, Leisel Finley and her family needed to replace the fence.

Finley, a sixth-generation rancher at Mount Echo Ranch in Amador County, said reconstruction costs were bid at $300,000 and would take at least a year to build, leaving the family without summer pasture and a herd of hungry cows to feed. Additionally, the U.S. Forest Service mandates that grazing be withheld for two years in postfire landscapes. This put the family in a difficult position.

While watching a recording of a California Cattlemen's Association meeting, Finley learned about a pilot program for virtual fencing. Desperate to find an alternative solution, she registered to try the livestock containment technology, which uses GPS enabled collars to monitor each animal's location in near real time.

Livestock producers can draw a perimeter on a map of their pasture using a laptop or smartphone application and send those instructions to the collar. The collar then uses audio and tactile cues to contain the animal in the area.

Eager to discover the short- and long-term benefits of virtual fencing, Finley turned to Scott Oneto, farm advisor, and Brian Allen, assistant specialist, from the University of California Cooperative Extension office in the Central Sierra. Since partnering with Oneto and Allen, Finley said she has come to understand and uncover more of the technology's potential.

The team has consistently observed the technology's value in integrating with and enhancing traditional livestock production systems across California. Though still in its early stages of development, the location tracking and containment system appears to provide time- and cost-savings that make it a game-changer for ranchers.

Ability to monitor location of animals in real time

Virtual fencing really stands out in its ability to monitor each animal's location in real time. During roundups, ranchers can use their smartphones to see their own location relative to their herd. The system can also send alerts if an animal crosses the virtual boundary or if a collar remains stationary for an extended period, potentially indicating that the animal is sick or that the collar has fallen off.

Rounding up cattle on large, forested grazing allotments can be challenging, as the process generally requires a group of people and many return trips to find every animal. Prior to virtual fencing, Finley and her father could gather about 85% to 90% of the herd in a week. Since using virtual fencing, Finley said one of their most recent roundups lasted three days, and they located every single cow.

Something that every livestock producer dreads is the notorious call from a neighbor or California Highway Patrol alerting them that one of their cows is out in the middle of the road. It always seems to happen at midnight or while they are out with friends or family. This scenario changes with virtual fencing.

Containment based on animal behavior

The containment system that virtual fencing is built on is based on animal behavior. When the animal crosses an invisible boundary, the collar emits an audio warning, prompting most animals to instinctively turn back into the desired area. If the animal doesn't respond, the collar delivers a mild electric pulse as a secondary deterrent.

Field trials by Oneto and Allen demonstrated the system's success. Recently, the team trained a herd of 37 cattle of mixed ages that had no previous exposure to virtual fencing. During the initial six-day training period, the cattle responded to the audio warning alone about 75% of the time when they approached a virtual fence boundary, with the remaining 25% of cases requiring an electric pulse.

After about three weeks, the herd was responding to audio cues alone about 95% of the time. The field trials also showed that the collars contain the livestock within the desired areas 90% to 99% of the time when the entire herd wears virtual fence collars and their basic needs for safety, connection to the rest of the herd, water, forage, shade, etc. are met.

Opportunities for improvement

While the technology is effective in its current capacity, there are notable areas where it can improve. One limitation to the system is the current reliance on cellular networks to operate. If an animal wanders into an area outside of coverage, the collar will continue to operate based on the last instructions but won't receive updates or report locations. This is especially a concern in many areas of California with poor cell reception, including the steep forested rangelands where many livestock producers have summer grazing allotments.

Another limitation is that some companies require a solar-powered base station with radio and cellular antennas to be placed on the pasture. These facilitate the transfer of animal locations and updates to the virtual fences. A base station going offline would create the same conditions as a drop in cell signal until the base station is repaired. Some companies are currently developing collars that bypass the need for these base stations.

The other major concern for ranchers is the cost for a virtual fencing system. The average rancher can expect to pay an estimated $20,000 to $30,000 in upfront costs. The cost to set up a base station alone is $5,000 to $10,000. However, this cost is highly dependent on several factors, including the manufacturer, the number of livestock to be collared, if the livestock are large or small ruminants, and the number of GPS base stations to cover the range.

According to Allen and Finley, the high cost of virtual fencing can be offset by the unique animal and land management benefits it can provide. “While physical perimeter fencing remains essential, VF is rapidly emerging as an innovative tool to control livestock with ease, precision, and flexibility in ways that were not previously feasible with traditional fencing,” Allen said.

Finley described the technology as a “game-changer” for her family.

Virtual fencing helps control invasive grasses, installing fuel breaks

While virtual fencing is designed to contain livestock without physical fencing, it is not intended to outright replace secure perimeter fencing. Instead, it operates best as a highly dynamic and adaptable cross-fence, allowing for more intentional grazing on the landscape to meet livestock production and natural resource conservation objectives within a secure physical perimeter.

With grant funding from the USDA Natural Resources Conservation Service, the UCCE team continues to work with Finley and other livestock producers to test these applications on California's diverse rangelands.

Within the Sierra Nevada and Coast Ranges foothills, these trials include using virtual fencing on cattle for targeted grazing of invasive grasses to support the recovery of native forage and installing fuel breaks within the wildland-urban interface to remove vegetation where the edge of a pasture meets urban housing.

Using virtual fencing, 25 cattle were successfully concentrated on a field of Medusahead (Elymus caput-medusae), an invasive annual grass. The herd respected the virtual fencing boundary 99% of the time despite nearby preferable forage. Grazing reduced medusahead seed heads from 2,072 per square meter in the ungrazed control area to just 68 per square meter in the grazed section.

In a different trial, 37 cattle with virtual fencing collars were contained within 120-feet-wide fuel breaks along the boundary of an annual rangeland and residential area. Cattle stayed within the boundaries 99% of the time, leading to an 81% reduction in fine fuel biomass and lowering wildfire risk in the wildland-urban interface.

Within rangelands on conifer forests, these UCCE trials concentrate cattle on brush to reduce the flammable plants and vegetation that competes with desirable timber species. It also can prevent livestock from entering sites that are sensitive to livestock presence.

Upcoming grazing trials will focus on how virtual fencing works with goats and sheep. In addition to Oneto and Allen, UCCE's contribution to virtual fencing research is in large part due to Leslie Roche, UCCE specialist and associate professor at UC Davis, Dan Macon and Jeff Stackhouse, UCCE livestock and natural resources advisors, Kristina Horback, associate professor at UC Davis and Lone Star Ranch in Humboldt County.

To learn more about the trials led by the UCCE team,visit https://cecentralsierra.ucanr.edu/Virtual_Fencing/ 

UC ANR experts, resources guide response to shothole borers in Bay Area

UC Cooperative Extension scientists, partners managed invasive beetle in Southern California

Late in 2023, a potentially devastating beetle was detected in the San Francisco Bay Area for the first time. But land managers, arborists and agency staff have one big advantage as they devise plans to control the invasive shothole borers (ISHB).

Thanks to collaborations led by University of California Agriculture and Natural Resources, they can draw upon the hard-earned experience of their colleagues in Southern California. Over the past decade, SoCal communities have lost “tens of thousands” of trees due to ISHB infestations, according to Beatriz Nobua-Behrmann, UC Cooperative Extension urban forestry and natural resources advisor for Los Angeles and Orange counties.

In one regional park, about 500 trees had to be removed in the span of just one year. “That kind of impact happened in many locations; a whole street might lose 90% of the trees – all of a sudden,” said Nobua-Behrmann, a member of a statewide network studying ISHB.

Spurred by such severe impacts, UC scientists have been studying ISHB and testing various control measures since about 2012. Their lessons are now informing efforts in San Jose – where the first case in the Bay Area was detected in November 2023 – and across the region.

“The UC ANR team is comprised of subject-matter experts,” said Drew Raymond, interim agricultural commissioner for Santa Clara County. “The team has compiled all of the experience from the agencies that have been doing work in Southern California and transplanted that experience here to Northern California.”

Lucy Diekmann, UC Cooperative Extension urban agriculture/food systems advisor, and Igor Lacan, UCCE environmental horticulture and urban forestry advisor, have coordinated regular meetings and trainings of Bay Area agricultural officials, land managers and arborists.

“Lucy and Igor have been instrumental in organizing our partners to establish an effective plan for shothole borers,” said Sara Davis, city forester for San Jose. “Because experts across the broader UC ANR network have many years of firsthand experience with this invasive pest, we are able to draw on their practical know-how to guide our monitoring, management and public education efforts.”

Davis is leading a trapping program in San Jose to determine how widespread ISHB is. Aside from a recent detection in the Santa Cruz Mountains, almost all of the approximately 30 confirmed cases in Northern California have been clustered along the riparian corridor of Coyote Creek through downtown San Jose. This pattern of intense but geographically limited damage was also seen across Southern California – notably in San Diego County along the Tijuana River Valley, where ISHB wiped out the willow population.

“I would expect us in the Bay Area to see this type of localized damage that is not fundamentally different from what they're seeing in Southern California,” Lacan said.

Unusually troublesome pest triggers deadly tree disease

The invasive shothole borers – a term for two species that are virtually indistinguishable, the polyphagous shothole borer and Kuroshio shothole borer – were first detected in Los Angeles in 2003. The tiny beetles, measuring 1.5 to 2 millimeters in length, became a major concern a decade later when swaths of urban forest began dying across LA County.

Infestations are harmful – and fatal for at least 17 tree species in California – because the fungus that the beetle “farms” as its food source causes a disease called Fusarium dieback. Alarmingly, ISHB make their home in a wide variety of trees; Nobua-Behrmann said 65 tree species in California have been identified as “reproductive hosts” where they can grow their populations.

“The fact that they are such a generalist species means that they can find a host almost anywhere,” she said, noting that sycamore, box elder, cottonwoods, oaks and willows are favorites of ISHB.

Furthermore, typical tools in the integrated pest management toolbox are unavailable or ineffective for this invasive beetle. Unlike most insects, these shothole borers mate with their siblings before leaving the tree, so they don't need to search for mates afterward. This means they are not attracted to the pheromone traps typically used for pest control; traps used for ISHB only work to track their numbers, not reduce them.

“Their biology limits what we can do,” Nobua-Behrmann said. “Since the beetles spend most of their lives inside the trees, it's also hard to reach them with insecticides.”

Largely hidden within trees, ISHB can build up their numbers, undetected for years. A tree with green and plentiful leaves may in fact be harboring a significant infestation. “It's easy for this beetle go under the radar and create a big population and a big problem before you even notice,” Nobua-Behrmann said.

Monitoring and early identification of infestations are crucial

Given this pest's elusive nature, monitoring and early intervention have proven to be essential in Southern California.

“All of the success stories have a major component of monitoring and detection; if you have a good monitoring program and you can quickly identify the trees that are infested, timely action can make a big difference,” said Nobua-Behrmann, citing Disneyland in Anaheim as one example where frequent surveys and robust monitoring prevented major impacts.

As most municipalities don't have the abundant resources of a world-famous theme park, Nobua-Behrmann pioneered a program in Southern California to train community members on recognizing telltale signs of the beetle. Specifically, they looked for its entry holes, which have a characteristically round shape and size, comparable to the tip of a ballpoint pen.

Beginning with UC Master Gardeners and UC California Naturalists and then members of the general public in LA and Orange counties (and later other SoCal counties), the program trained about 100 people on how to look out for the beetle. After verification by experts, volunteers were found to be nearly 90% accurate in identifying ISHB.

Although the volunteer monitoring program is on hiatus, Nobua-Behrmann said it had clear benefits that could potentially help other regions. “It would be great to get this program going in Northern California and hopefully get volunteers and people in the general public to help identify infestations there as well,” she said.

Statewide ISHB network spreads essential information

In addition to coordinating an in-person public training in San Jose in April, Lacan and Diekmann, the UC Cooperative Extension advisors, have been educating local UC Master Gardeners on how to spot signs of the invasive beetle.

For about a decade, Lacan has been warning people about the possibility of ISHB in Northern California, routinely including shothole borers in his presentations on “tree pests to watch.” “I've been doing this since before ‘day zero,' but there was not a whole lot of interest in ISHB, as you might imagine,” Lacan recalled. “But then all of that changed in fall of last year.”

In the past year, Lacan has done a dozen ISHB presentations, workshops and webinars, attended by a total of about 260 people – predominantly city foresters, land managers, production arborists and members of tree-related nonprofits.

Lacan noted that the most effective presentations have been at in-person events featuring UC ANR-affiliated experts such as Nobua-Behrmann, UCCE environmental horticulture advisor emeritus John Kabashima, and ISHB program staff Randall Oliver and Hannah Vasilis.

“Here is where we tap into our network,” Lacan said. “This is the power of the statewide shothole borers program.”

Another vital asset has been the collection of practical resources gathered by the ISHB program, the UC Integrated Pest Management team and partner organizations. One example is a deck of identification cards depicting how symptoms of infestation differ from species to species. Such detailed information can help managers determine whether a tree is truly infested – and thus allocate their limited resources more judiciously.

“These very specific, very seriously considered materials are the kind of thing that people really appreciate,” Lacan said. “It's not just a generic ‘it's kind of like this.'”

The symptoms, broken down by tree species, are also listed on the ISHB website. Raymond, the interim agricultural commissioner for Santa Clara County, said his team uses the website to get informed about ISHB and regularly refers community members to it.

“The ISHB website has been a great resource,” Raymond said. “It's full of important and user-friendly information.”

Communities learn to protect trees, adapt to shothole borers

If community members believe a tree is infested, they should review the symptoms of ISHB-Fusarium dieback. If the signs match what they are seeing, they should take a photo of the entry hole (with the tip of a ballpoint pen placed next to the hole as reference) and send images to their county agricultural commissioner's office or local UCCE advisor, who may then seek confirmation.

Extra eyes on urban forests are crucial to help experts identify potential “amplifier trees” – heavily infested trees, with more than 150 entry holes, that are often repeatedly reinfested by subsequent generations of beetles. They contribute to the recurring pattern of severe but localized infestations seen across Southern California – and now in San Jose.

New research suggests that removing severely infested trees – or just the most impacted limbs of those trees – can significantly lower the overall ISHB population and help less-infested trees in the area recover over time.

“You're not going to eradicate ISHB (at least not in Southern California); you're not going to get rid of them – you're going to have them forever,” Nobua-Behrmann said. “But you can keep them at a manageable amount.”

She also emphasized other actions the public can take to prevent the spread of ISHB, such as correctly disposing infested plant material – ideally chipping it to less than an inch in length (or as small as possible) and then composting the chips.

“It's also important to not move firewood and instead buy it where you will be burning,” Nobua-Behrmann said. “It's one of the best things people can do to protect trees from invasive pests.”

After identifying and removing amplifier trees, land managers and landscape arborists should have a plan for replanting, Lacan added. He said they should prioritize species that are less susceptible to the beetle, using his Pest Vulnerability Matrix tool that lists the major pests for different mixes of trees.

“We need to figure out how to have sustainable urban forests, even with this pest,” he said. “We know we can do it, largely thanks to our colleagues in Southern California. So the key lesson is to replant soon – choose smartly, but replant right away.”

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