- (Public Value) UCANR: Safeguarding abundant and healthy food for all Californians
- Author: Mike Hsu
UC researchers studying how practice can help farmers manage drought, pests, other challenges
Due to severe water shortages, rice acres planted in California plummeted by 37% from 2021 to 2022, according to numbers released recently by the U.S. Department of Agriculture's National Agricultural Statistics Service. But now, thanks to University of California researchers, growers have a new tool they could potentially use to cope with droughts and other environmental and socioeconomic changes.
A crop rotation calculator provides farmers in the Sacramento Valley – where 97% of California rice is grown – with projections on the economic impacts of transitioning their fields from rice into four less water-intensive crops: dry beans, safflower, sunflower or tomato.
The tool represents an initial attempt to address the dearth of research on rice crop rotation in California, while giving growers much-needed, science-backed data on whether the practice would make financial sense for their farms.
“I believe more rice growers could benefit from the many advantages of crop rotation, and this new tool is an excellent first step by the UC to help growers look into making such a transition,” said George Tibbitts, a Colusa County rice farmer.
Funded in part by the USDA National Institute of Food and Agriculture, through the Western Integrated Pest Management Center, the calculator is a collaborative effort of UC Agriculture and Natural Resources, UC Integrated Pest Management and UC Davis to fill a major gap in rice research.
“I do think there are people who would have tried rotational crops in the past, but it's just so unknown, we didn't have anything we could give them and be like, ‘Hey, this is the recommended crop for your area,'” said Whitney Brim-DeForest, UC Cooperative Extension rice advisor. “This tool gives them some preliminary data they can use to make a more informed decision.”
Crop rotation a potential boon to growers, environment
UC Davis doctoral student Sara Rosenberg and Brim-DeForest, alongside other members of the UC rice research team, surveyed California rice growers in 2020 on their experiences with and perceptions of crop rotation. Although the practice is rare in the Sacramento Valley (only an estimated 10% of rice acreage is under rotation), some farmers reported benefits that could be crucial in a water-scarce future.
“From having conversations with growers who do rotate, one of the biggest benefits they describe is their flexibility in times of drought, where they can keep producing on their land when there isn't enough water to grow rice,” said Rosenberg, noting that crop rotation could be one option in a “toolbox” of strategies that growers also use to manage fertilizer price shocks, herbicide resistance and other challenges.
During the ongoing drought that caused about half of California's rice acreage to go fallow in 2022, Tibbitts said his water district was only able to allocate 10% of his usual allotment.
“With such a limited supply, it would have been tough to grow even one field of rice,” he said. “But it was enough water so that we could rent two of our fields to a tomato grower – tomatoes under drip irrigation use much less water than a flooded field of rice. We were also able to grow one field of sunflowers, which doesn't need any irrigation at all if you can plant the seeds into existing moisture in the early spring.”
While drought is one motivating factor to rotate crops, Tibbitts said that on principle he avoids planting all his acreage in rice and “not have all (his) eggs in one basket.”
“My primary motivation for rotating into and out of rice has been to help with weed and disease control,” he added. “Crop rotation is a primary tool of IPM (integrated pest management), and I feel it has helped me greatly over the years.”
According to Brim-DeForest, rotating cropping systems can allow for the use of different weed control tools, such as different herbicide modes of action, and different cultural controls such as tillage, reducing the chances of selecting for herbicide-resistant weeds – an increasingly pervasive issue in rice systems.
Rosenberg noted that, in some situations – and depending on the crops in rotation – the practice can also disrupt the life cycles of insects and diseases and potentially improve soil structure and increase nutrient cycling and uptake, which may lead to a reduction in inputs such as fertilizer.
More research on crop diversification needed in rice systems
The benefits of crop rotation for California rice growers are largely theoretical and anecdotal, however, so the UC rice team is looking to add evidence-based grounding through a variety of studies – from looking at long-term effects on soil health indicators to testing various cover crops (which may deliver some benefits of diversification, similar to those of rotation).
“In California, there is no quantitative data on crop rotation in rice,” said Brim-DeForest. “You'd think after a hundred and some odd years (of UC agricultural research), all the research would have been done, but, no – there's tons still to do.”
Through interviews with Sacramento Valley growers, researchers found that cost was frequently mentioned as a barrier to trying crop rotation, along with incompatible soil conditions and a lack of equipment, knowledge and experience.
To help clarify those economic uncertainties, the new calculator tool allows growers to enter baseline information specific to their circumstances – whether they rent or own their own land, whether they contract out the work to plant the rotational crop, and other factors. The calculator then generates potential costs and benefits of staying in rice versus rotating to dry beans, safflower, sunflower or tomato, during the first year and in an “average” year for those crops.
The upfront costs of rotation during “year one” can be daunting. Therefore, the tool only focuses on a short-term profitability perspective. Researchers are currently working on longer term modeling for crop rotation – incorporating the possibility of reduced herbicide use over time, and under different crop yield scenarios, for example – that could significantly change the growers' calculus.
“You could actually be profitable in the long term, whereas this first, short glimpse is showing you a negative,” said Rosenberg.
In addition, thanks to collaboration with the UC IPM team, the rice rotation calculator is an evolving tool that will be continually improved based on user feedback and additional data. Brim-DeForest also said that it could be adapted to other cropping systems – for example, alfalfa going into another rotational crop.
The rice calculator tool can be found at: https://rice-rotation-calculator.ipm.ucanr.edu/.
Other contributors to the project include Bruce Linquist, Luis Espino, Ellen Bruno, Kassim Al-Khatib and Michelle Leinfelder-Miles of UCCE; Cameron Pittelkow of UC Davis; as well as UC IPM team members Chinh Lam, Tunyalee Martin and Hanna Zorlu; and the California rice growers and industry members who participated in the research.
- Author: Michelle Leinfelder-Miles
- Posted by: Gale Perez
In 2022, I estimate rice acreage in the Delta, south of the Yolo Bypass, was at least 8,000 acres. Most Delta rice is grown in San Joaquin County, but there is some acreage in Sacramento County. While Delta rice acreage is relatively small compared to that in the Sacramento Valley, it has been steadily increasing over the last several years (Table 1).
Given the increasing interest in rice production among Delta growers, and the differences in production practices from the Sacramento Valley, UC Cooperative Extension and UC Davis will be releasing a cost of production report specifically for Delta rice later this year or in early 2023. A Delta rice cost study was last produced in 2007, so updating the study was long-overdue. I want to thank all the growers who participated in a focus group to update the study.
Cool temperatures can make the Delta a challenging place to grow rice. Low night-time temperatures can cause blanking, which results in empty grains. Growers are limited to using only very-early and early maturing varieties. Most of the Delta acreage was planted with variety M-206, but some growers also planted a portion of their acreage with M-105. In 2022, we continued the UCCE Delta variety trial, which will help to identify and advance cold-tolerant varieties. The Delta trial is part of a statewide network of trials, led by UC Rice Extension Specialist, Bruce Linquist, and coordinated by Staff Researcher, Ray Stogsdill. I anticipate that the statewide results will be ready in time for the February Field Notes newsletter.
This year, I worked with growers and consultants on a handful of pests. Weed management is always top-of-mind for rice growers. There are limited practices and products that can control problematic weeds, and in some circumstances, the weeds may develop resistance to the herbicides that are available. If herbicide resistance is suspected, please contact me so that we can submit weed seeds for testing. We would collect the seeds in the late summer or early fall when they have matured but have not shattered. Resistance testing is overseen by UC Weed Science Extension Specialist, Kassim Al-Khatib, and takes place in greenhouses during the winter. By the following spring, we provide the grower with information on which herbicides are still working and which are not.
Over the last several years, I have conducted trials to evaluate the efficacy of a new herbicide product, Loyant (florpyrauxifen-benzyl; Corteva Agriscience), on grasses and sedges in the Delta drill-seeded system. (See https://ucanr.edu/sites/deltacrops/files/361256.pdf for project reports.) Loyant is now registered and will be available for the 2023 season. This year, I collaborated with graduate student, Deniz Inci, and Kassim Al-Khatib to evaluate product efficacy on cattails. With only one year of data, we cannot make too many conclusions, but it appeared that Loyant had efficacy on small cattails (less than three feet tall, Figure 1). The results were promising, and we will continue our investigation next year to see what more we can learn.
I have been trapping armyworms in the Delta since 2016 (Figure 2), in collaboration with fellow farm advisor, Luis Espino. The traps catch true armyworm moths. They were deployed on three ranches and monitored weekly. In 2022, we recovered the highest moth counts since 2017, and the peak flight occurred about one week earlier than in 2017. This is important information for management because, based on the armyworm life cycle, we know that peak worm populations occur approximately two weeks after peak moth flight. In other words, growers can make informed decisions based on the monitoring data and adapt their management to the field conditions. Trap monitoring is one part of an integrated pest management program for armyworms, which also includes scouting for feeding damage and the worms themselves. Over the years, I have observed armyworms in riparian and wetland vegetation that neighbor rice fields, so it is important to scout those areas, too. More information about Delta armyworm trapping is available on my website (https://ucanr.edu/sites/deltacrops/Rice/Armyworms/).
I observed a couple important diseases this year – stem rot and rice blast. In recent years, we have observed stem rot on certain ranches at harvest. As fields were getting drained, the plants turned brown instead of golden, and grains hadn't filled (Figure 3). We developed post-harvest straw management programs that included burying the residue to try to break down the fungal inoculum. This year, we noticed the problem in some locations early enough to make treatment decisions. We walked the fields at late-tillering and early-heading and found black lesions on the stems at the water line (Figure 4). We submitted samples to UC Plant Pathology Extension Specialist, Cassandra Swett, and confirmed stem rot. Treatment timing is critical for managing stem rot, and treatment at early-heading has been observed to be most effective. There is a tendency for stem rot to be more severe on low potassium soils, and many Delta soils are naturally low in potassium. A potassium fertility program may help mitigate disease severity, but management should include a multi-pronged approach that also includes post-harvest straw management and possibly fungicide applications. Currently, there is no varietal resistance to the disease. The rice blast that was confirmed was in one field. We observed lesions below the panicle (“neck blast”) that caused blanking. Blast spores can move by air, are favored by warm, wet conditions, and can be exacerbated by excess nitrogen. Fungicides are registered and are most effective at early-heading. For more information on both of these diseases, see the fact sheets written by Luis Espino (https://rice.ucanr.edu/FactSheets/Rice/), or give me a call.
We should continue to keep weedy rice on our radars because we have seen it in the Delta in the past. Where we have observed light infestations, it appears that keen management – including in-season rogueing, post-harvest management that includes straw chopping but not incorporation, and winter flooding – can reduce, if not eliminate the pest. These are our management tools until a herbicide is approved for spot-spraying. Growers should also pay attention to equipment sanitation – harvesting weedy rice fields last (if possible) and thoroughly cleaning out equipment after harvesting fields where weedy rice has been observed.
Finally, I will be starting new projects this winter, in collaboration with fellow farm advisor, Whitney Brim-DeForest, and graduate student, Sara Rosenberg, to evaluate winter cover cropping between rice crops. Our objectives are to evaluate carbon and nitrogen cycling and variety survivability during the cool, wet (we hope!) winter conditions. These projects are supported by the CDFA Healthy Soils Program and the CA Rice Research Board. I look forward to sharing results in the years to come.
I am grateful to work with a great team of UC colleagues on these rice projects. I am also grateful for all the growers who have collaborated with us. I wish everyone a good end to the year, and I look forward to working with you again in 2023.
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Michelle Leinfelder-Miles is the UC Cooperative Extension Delta Crops Resource Management Advisor serving San Joaquin, Contra Costa, Sacramento, Solano, and Yolo counties.
Original source: Rice Notes -- November 2022 newsletter
- Author: Pamela Kan-Rice
UCCE, USDA California Climate Hub launch CalAgroClimate decision-support tool
Climate and weather variability pose increasing risks to farmers. As world leaders gather in Egypt at COP27 to address the climate crisis, University of California Cooperative Extension and the USDA California Climate Hub are launching new web-based tools to provide farmers with locally relevant and crop-specific information to make production decisions that reduce risk.
“Integrating historical weather data and forecast information with meaningful agricultural decision support information holds the potential to reduce a crop's vulnerability to such risks,” said Tapan Pathak, UC Cooperative Extension climate adaptation specialist at UC Merced.
Pathak is collaborating on building the decision support tool with partners from the U.S. Department of Agriculture, California Climate Hub, UC Cooperative Extension and UC Agriculture and Natural Resources' Informatics and Geographic Information Systems or IGIS.
“CalAgroClimate has been designed to support climate-enabled decision making for those working in the California specialty crop industry,” said Steven Ostoja, Director USDA California Climate Hub. “The USDA California Climate Hub is a proud collaborator on this important initiative to ensure the state's agricultural industry can continue to thrive in a future of climate change.”
Shane Feirer and Robert Johnson of UC ANR IGIS designed the interactive tools on the website and Lauren Parker of the USDA California Climate Hub contributed to content organization.An advisory panel composed of colleagues from UCCE and the Natural Resources Conservation Service ensure CalAgroClimate tools are relevant to stakeholder needs.
“CalAgroClimate is an amazing new tool that puts comprehensive past and forecast weather data at any grower's disposal,” said Mark Battany, UC Cooperative Extension water management and biometeorology advisor for San Luis Obispo and Santa Barbara counties.
“California's high-value crops are subject to a myriad of weather-related risk factors; this tool will allow growers to better address both near-term and long-term risks, and in the end grow more profitably, said Battany, who is a member of the CalAgroClimate advisory panel.
Growers and crop consultants can use CalAgroClimate's crop and location-specific tools and resources to help make on-farm decisions, such as preparing for frost or untimely rain and taking advantage of expected favorable conditions.
CalAgroClimate currently includes heat advisory, frost advisory, cropphenology and pest advisory tools.
Heat advisory tool: Extreme heat poses a danger for people, animals and crops. With this tool, users can select location and temperature threshold (e.g. 90 F, 95 F 100 F) based on their crop-specific heat tolerance level and the tool will provide a customized map of heat risk for next seven days for that location, including the number of consecutive days with temperature above that threshold. Users can also assess overall heat risks across the state for a selected temperature threshold as well. Having an early warning about hot temperatures, growers can take steps to reduce risks associated with extreme heat such as providing shade, changing farm workers' schedules and applying additional irrigation.
Frost advisory tool: Frost risk is a very serious issue for many specialty crops across California. Similar to the heat advisory tool, this tool provides a customized map of frost advisory for next seven days for a user's location, and forecast of consecutive days with temperature falling below the selected temperature thresholds (e.g. 35 F, 32 F, 28 F). Similar to the heat advisory, early warning about cold temperatures can provide growers some time to protect their crops from frost damage.
Crop phenology tool: The scientists have developed a-crop specific and location-specific crop phenology tool to help users keep track of growing degree days accumulations and estimate critical growth stages. CalAgroClimate uses a high-resolution PRISM dataset to provide near real-time crop phenology information to users. This tool will inform growers about how their crop development compares to previous years, which can be helpful in planning activities specific to critical growth stages.
Pest advisory tool: Similar to crops, development of certain pests and diseases is controlled by temperature and heat unit accumulations. With the pest advisory tool, growers can keep track of estimated pest generations during the growing season to make pest management decisions.
“We are launching the website with this initial set of tools while working on adding more crop-specific information and several new tools in the near future, ” Pathak said. “We look forward to getting feedback from growers who use CalAgroClimate to make it even more useful.”
- Author: Mike Hsu
Preliminary results indicate 3.5% of ACP collected showed signs of bacterium that can cause huanglongbing
An ongoing study in the commercial citrus groves of coastal Southern California is looking at whether Asian citrus psyllids – the insect vector of huanglongbing “citrus greening” disease – are carrying the bacterium that can cause HLB.
Thus far, the project has tested more than 3,000 adult ACP collected from 15 commercial citrus sites across the region, of which 138 – just over 3.5% – had some level of the bacterium present, according to researchers from UC Agriculture and Natural Resources, UC Davis, UC Riverside and the University of Arizona, Tucson.
“While the results are a cause for concern, the situation in California is much better than in Florida and Texas, where ACP carrying the bacterium make up the majority of the population and HLB is widespread in commercial citrus,” said Neil McRoberts, a UC Davis plant pathologist and UC Integrated Pest Management program affiliate advisor. “The results indicate that there is no room for complacency, but also no cause for panic.”
Since the first HLB-infected tree in California was found in 2012, nearly 4,000 infected trees have been detected and removed from residential properties in Southern California, mainly in Orange and Los Angeles counties. According to McRoberts, “to date, no HLB has been found in commercial citrus” in California.
He stressed, however, that the aforementioned ACP study – funded by the HLB Multi Agency Coordination Group and managed by USDA-APHIS – does not involve any testing of trees for HLB and focuses only on looking at the insect which spreads the bacterium.
McRoberts also emphasized that the project's detections of the bacterium cannot be considered “official” because the researchers' lab procedures differ from the official testing protocols of the California Department of Food and Agriculture.
“Follow-up sampling by CDFA staff would allow official samples to be collected for further investigation, but is entirely voluntary for the growers involved,” he said, adding that his research team is currently wrapping up the sampling phase of the project, with data analysis continuing into 2023.
While commending the “huge coordinated effort” by the California citrus industry, California Department of Food and Agriculture, UC ANR and other partners to suppress the ACP vector and slow the spread of HLB, McRoberts also urged continued vigilance.
“Our study results indicate that it is not time to declare the emergency status for ACP/HLB in California over – the situation is still evolving,” he said.
For further information about the research, contact Neil McRoberts at nmcroberts@ucdavis.edu or (530) 752-3248.
- Author: Deborah Schnur
For the first time in three years, the California Agriculture in the Classroom Conference was held in-person this past September. Ventura County, with its rich agricultural heritage, was the perfect location for the conference to make its comeback. Growing up on the beaches of Long Island, New York, I was excited to attend the conference and spend some time by the shore. The conference agenda was filled with opportunities to learn and network through tours, presentations, exhibits, workshops, and discussions. Best of all, I returned home with three full bags of materials to use for school and environmental education.
Pre-Conference Tour and Reception
My second favorite part of the tour was walking through Air Force One and seeing how it was used during Reagan's time. The plane was retired after Reagan left office and moved to the site of the Library, where the building was constructed around it. The Air Force One Pavilion also houses vehicles from the presidential motorcade.
After the tour, I returned to the hotel for conference registration and a reception with Maureen McGuire,CEO of the Farm Bureau of Ventura County. I also took some time to network with exhibitors including the California Farm Bureau, California Women for Agriculture,Ventura County Farm to School, Students for Eco-Education and Agriculture (SEEAG), and the Ventura County Agricultural Museum.
Opening Session
The last speaker was Christine Birdsong, the Undersecretary of the California Department of Food and Agriculture, who emphasized the importance of agricultural literacy for students and teachers. Because California has about 24 million acres of agricultural land and $20 billion in agricultural exports, the state's economic health is closely tied to agriculture. Agriculture is a growing career field that increasingly relies on technology, and a diverse group of young farmers is needed to replace those who are retiring.
Workshops
The opening session was followed by two workshop sessions. The first workshop I attended was “Youth Can Run a School Garden Program”, presented by Abbi Mars of UC CalFresh Healthy Living and students from Arthur Hapgood Elementary in Lompoc. I was inspired to hear how fifth and sixth grade students run all aspects of the school garden and teach younger students about gardening and nutrition. The student leaders rotate through different teams to learn about composting, fruit tree care, hydroponics, harvesting, and teaching. At the end of the workshop, the students gave a demonstration of the “Pest or Pal?” lesson from the CalFresh TWIGS (Teams with Intergenerational Support) curriculum.
My second workshop was “Bringing Gardening into the Classroom”, led by Veronica VanCleave-Hunt of CalFresh Healthy Living. She and her colleague presented three TWIGS garden lessons that can be taught in the classroom without a garden. The first lesson was “Seed Magic” where students dissect a seed and identify the parts. The workshop attendees received lima bean seeds that had been soaked in water and were instructed to remove the seed coat and identify the leaves, root, and cotyledon (food source). Who knew a simple seed could be so interesting?
The second lesson was “Soil” where we used our senses to observe the soil components of sand, silt, and clay. Then we learned how to conduct a soil test by mixing a soil sample with water in a jar and watching the layers separate. The final lesson was “Eat Your Plants” about how food can come from all plant parts: roots, stems, leaves, flowers, fruits, and seeds. The workshop instructors passed around bags, and the attendees tried to identify the fruit or vegetable inside and the plant part.
After the workshops, we were treated to a hearty lunch and an engaging talk from Coach Kiah Twisselman Burchett, “Grow Through It: Blooming Through Hardship”. Coach Kiah is a cattle rancher turned motivational speaker who shares her triumphs and struggles with body image and weight loss to empower others to find joy in life.
Field Trips and Taste of California Dinner
The day ended with the Taste of California at the Ventura County Agriculture Museum in Santa Paula. Each of the 13 tables was decorated according to a theme by a host organization. Hosts ranged from the Santa Paula High School Ag Department to the California Farmland Trust. I opted for the “CA Central Coast Cornucopia of Freshness” table hosted by the California Women for Agriculture, Ventura County. After a welcome from Shannon Douglass of the California Foundation for Agriculture in the Classroom, Coach Kiah took the reins as the emcee for some table games. At the end of the night, I filled a bag with take-home gifts of seeds, citrus, trail mix, and local Blue Ridge honey from my table host.
Closing Sessions
After the panel were the Make ‘n Takes, 20-minute activities to share with students. During the Beads and Books session, I made a daisy beaded bookmark from natural materials. From the Orange You Glad We Have Farmland? session, I learned the percentage of land available to grow food for the world–only 3 percent! The MyPlate Nutrition activity demonstrated ways to introduce the five food groups to students and help them list foods in each group.
I was sad to see the California Ag in the Classroom Conference come to an end but happy to spend a few hours on the beach before heading home. Next year, I look forward to attending the state conference again and maybe even the national conference in Orlando! If you're involved in agriculture education, I highly recommend checking out the resources that Ag in the Clasroom offers at https://learnaboutag.org and https://agclassroom.org.
Have you enjoyed reading this blog? Do you have questions? Need help with school gardens or environmental education? If so, send an email to dschnur@ucanr.edu. I look forward to hearing from you.
