Nutrition Policy Institute rolled out an online evaluation tool, EATS, for local health departments to evaluate school-based CalFresh Healthy Living during pandemic-related school closures. EATS data showed that students receiving school meals during the closures were more likely to eat fruits and vegetables, an important insight that could impact school nutrition policy in the future.

The Issue

In March 2020, schools across California shuttered in an effort to protect students and staff from COVID-19 infection. School closures impacted provision of the National School Lunch Program and School Breakfast Program, and thus, the nutrition safety net they provided. School districts across the state pivoted to centralized meal distribution via grab-and-go and drive-up, or even utilized home delivery in some cases. Despite monumental efforts to get school meals to the children who needed them most, meal participation declined significantly during this time. 

The California Department of Public Health's CalFresh Healthy Living Program (CDPH-CFHL) prioritizes improving child nutrition security and diet quality. Local health departments partner with K-12 schools to implement CFHL nutrition education and policy, systems, and environmental (PSE) change strategies that aim to increase consumption of fruits and vegetables and decrease consumption of sugary drinks. Their existing relationships with school districts enabled them to support efforts to ensure that school meals met dietary standards and student needs during school closures. 

How UC Delivers

During the pandemic, local health departments modified their school-based programs to continue to reach students outside of the school setting. For example, they delivered nutrition education remotely via Zoom or pre-recorded lessons, and they pivoted to PSE change strategies like modifying school meal distribution practices to help ensure students continued to have access to healthy foods.

Nutrition Policy Institute supports local health department evaluation of school-based CDPH-CFHL interventions, and without modifying the existing data collection methodology to reach students learning at home, evaluation would not have continued. Evaluators adapted their methods, including migration of the Eating and Activity Tool for Students (EATS) to an online platform. This survey measures student eating and physical activity behaviors, and during pandemic school closures, included questions about if and where students ate school breakfast and lunch. Nutrition Policy Institute prioritized school data collection during this extraordinary period, understanding that analysis of these data could draw attention to the impacts of COVID-19 on California's youth, in particular, those already facing nutrition disparities.

The Impact

During the 2020-21 school year, as a result of Nutrition Policy Institute's development and coordination of the online EATS tool, local health departments were able to collect data from 3,297 4th and 5th grade students from 67 CFHL-eligible schools (where at least half of students are eligible for free or reduced-price meals). About half of students were female (52%) and half identified as Latino (50%). Most students were attending school exclusively by distance learning at the time of the survey (83%). Approximately one quarter of students had eaten at least one school meal the previous day (27%), with about 1 in 7 reporting they ate both breakfast and lunch (15%).

We found that students who ate one or two school meals a day had significantly higher intakes of vegetables, whole fruits, and 100% fruit juice, compared to students who did not eat school meals. Specifically, students who ate one school meal a day ate more beans and orange vegetables, while those who ate two school meals a day consumed a wider variety of vegetables, including beans and orange vegetables. However, children who ate one school meal a day drank more fruit drinks (non-100% juice) and flavored milks than those who did not eat school meals. Further, students who ate two school meals consumed more fruit drinks, flavored milks, and sports and energy drinks than those who did not eat school meals.

Our findings suggest that school meals continued to be an important source of fruits and vegetables for school-aged children during the pandemic. This highlights the importance of focusing PSE efforts on improving school meal distribution and overall quality, should students' in-person attendance be challenged again. Despite this, findings also underscore the need to reduce consumption of sugary drinks, which are a primary source of added sugars and nutrient poor energy in children's diets. This highlights an opportunity to strengthen school-based CFHL interventions by incorporating nutrition education and PSE strategies that focus specifically on healthy beverage consumption. Nutrition Policy Institute's leadership of CDPH-CFHL local program evaluation not only highlights the successes of CFHL, but just as important, the areas for program improvement. Nutrition Policy Institute's commitment to strengthening CDPH-CFHL interventions in California schools is a hallmark of UC ANR's public value of promoting healthy people and healthy communities.

This study was conducted as part of a contract with the California Department of Public Health with funding from the United States Department of Agriculture (USDA) Supplemental Nutrition Assistance Program-- SNAP. These institutions are equal opportunity providers and employers. 

UC Digital Agriculture Program's innovative spray backstop system reduces airborne pesticide drift by 78% in almond orchards– a big step forward for improving air quality and working conditions in California's agricultural production areas. 

The Issue

Pesticide drift is a significant concern, especially in California's almond orchards. It's not just an environmental issue. Pesticide drift can pose a public health risk by contaminating the skin, lungs, and gut of people in nearby communities. These chemicals can lead to respiratory issues, skin irritation, and other adverse health effects. Another study highlights that pesticide poisoning is a significant cause of morbidity and mortality, affecting not just agricultural workers but also the general population.The challenge has been to control this drift without reducing the effectiveness of the pesticide application. This project aims to tackle this pressing issue head-on.

How UC Delivers

Addressing the issue of pesticide drift requires a multi-disciplinary approach, combining engineering, agriculture, and environmental science expertise. The UC Digital Agriculture Program team rose to the challenge by developing an innovative spray backstop system. This system is a blend of practicality and advanced technology, designed to be both farmer-friendly and effective in reducing pesticide drift.

The core components of this system are a foldable mast and a shade structure. The mast is the backbone, providing the necessary height and stability, while the shade structure acts as a barrier covering the trees from the top. This barrier is crucial in preventing the upward movement of pesticide droplets, thereby reducing the potential for drift.

Figure 1: Schematic design of the backstop prototype installed on a sprayer in an almond orchard.

To validate the effectiveness of this system, a series of tests were conducted in young almond orchards. The sprayer was operated at a 3.2 km/h speed to simulate real-world conditions. But before hitting the field, the team employed advanced uncrewed aerial systems equipped with thermal and RGB cameras. These cameras captured images and videos of the spray pattern from multiple angles, providing invaluable data for analysis.

The aerial imagery was not just for show; it played a pivotal role in the project. It allowed the team to monitor the spray application in real-time and understand the spray cloud's movement pattern. This imagery was then used to refine the design of the shade structure, ensuring it effectively blocked droplet movement beyond the treetop.

Figure 2: Aerial views showing the efficiency of the backstop prototype in blocking the spray cloud.

The results were more than just promising. The backstop system effectively blocked the spray cloud, ensuring that the pesticides stayed precisely where they were intended to be—on the trees. This was further validated through a ribbon test, a simple yet effective method to measure drift. A ribbon placed in the spray path remained in its resting position when the backstop system was used, indicating a significant reduction in drift.

The project didn't stop at just reducing drift; it also ensured that the reduction did not come at the cost of effectiveness. The on-target deposition of the pesticide was not compromised, affirming that the system could achieve dual objectives: reducing drift while maintaining efficacy.

The Impact

The spray backstop system's impact goes beyond just numbers. It represents a significant stride toward sustainable agriculture and community well-being. The system successfully reduced the drift potential by 78%. This isn't merely a statistic; it's a tangible change that has far-reaching implications for both environmental stewardship and human safety.

Figure 3: Statistical results showcasing a significant reduction in drift potential.

The environmental impact is equally noteworthy. Reduced drift means fewer chemicals in the air, contributing to "improved air quality," a UC ANR condition change. This is a step forward in reducing air pollution, which has wide-ranging implications for human health and climate change.

One of the most noteworthy aspects of this innovation is that it managed to reduce drift without compromising the effectiveness of the pesticide application. The on-target deposition remained consistent, ensuring the almond trees received the necessary pesticide coverage for optimal growth and yield. This is a crucial factor for farmers who are often caught in the dilemma of choosing between effective pest control and environmental responsibility.

Figure 4: Comparative leaf samples illustrating consistent on-target deposition and coverage.

The project aligns with another UC ANR's condition change, "improved living and working conditions for California's food system and farm workers." One of the goals of reducing pesticide drift is to mitigate the health risks associated with working and living in agricultural production areas. Therefore, the work directly supports UC ANR's commitment to promoting the public health of California's communities.

Looking ahead, the project has set the stage for further research and development to adapt the system for different types of orchards and terrains. Additional modifications are being considered to make the system even more robust and versatile, ensuring its long-term sustainability and broader applicability.

Want to learn more? See the method in action here.

UC ANR supports California's almond crop protection workforce through Airblast Sprayer Calibration Trainings to maintain or improve their technical knowledge. 100% of participants reported both learning professional skills and their intent to adopt practices that can improve the sustainability and profitability of California ag.

UCCE farm advisor Dr. Franz Niederholzer and UCCE specialist Dr. Peter Larbi pose behind an airblast sprayer in Arbuckle, CA

The Issue

For efficient and effective pesticide spray application, all sprayers should be calibrated as often as necessary throughout the growing season of almonds, especially when dealing with orchards of different ages and sizes. Calibration is considered a best practice in pesticide spray application ensuring accurate application rates and adherence to pesticide labels which is the law. As such, proper understanding of sprayer calibration objectives and steps is needed to avoid using incorrect methods that give a false sense of accuracy. Educating growers and applicators in calibration methods will therefore empower them to ensure the use of properly calibrated sprayers well-adjusted to the target canopy to deliver maximum crop protection while minimizing pesticide loss. 

How UC Delivers

In June 2023, UC ANR co-hosted two Calibration Safety & Compliance Training events, one for Northern California and the other for Central California, with the Almond Board of California (ABC), AgSafe Food and Farms (AgSafe), and the Western Agricultural Processors Association (WAPA). The Northern California training was held at the Nickels Soil Lab in Arbuckle, CA, while the Central California event took place at the UC's Kearney Agricultural Research and Extension (KARE) Center in Parlier, CA. The events were aimed at providing practical calibration training on how to prepare and calibrate airblast sprayers as well as compliance training such as how to manage required documents for pesticide applications. The 4.5-hour trainings included “Welcome” by the ABC, “Regulatory Update” by WAPA, “Calibration Training” by UC ANR, “Headquarters Compliance Training” by AgSafe, and “DPR Laws & Regulations Update” also by AgSafe. The DPR approved 4.0 hours of continuing education credits – 2.0 ‘Laws' and 2.0 ‘Other' – for qualifying participants. Overall, 50+ attendees participated in both events: 30+ in Arbuckle and 23 in Parlier.

The Calibration Training by UC ANR was a 2-hour practical session conducted in an almond orchard along with airblast sprayer demonstrations. It was presented in an interactive format allowing participants to interject with questions, comments, and observations. The Northern California training was led by UC Cooperative Extension advisor Dr. Franz Niederholzer in collaboration with UC Cooperative Extension specialist Dr. Peter Ako Larbi. Alternatively, the Central California training was led by Dr. Larbi in collaboration with Dr. Niederholzer. Both sections covered: “Sprayer parts review”; “Sprayer calibration basics and calculations”; “Sprayer speed determination”; “Sprayer air profile assessment and nozzle configuration”; “Flow rate measurement”; and “Spray coverage evaluation”. Staff from the Nickels Soil Lab, the Agricultural Application Engineering (AgAppE) Lab, and KARE Center provided Logistical, technical, and documentation support. The participants completed evaluation forms to provide feedback for just the Calibration Training section. Comments from the evaluation forms included…

“Very good class.”

 “Great rapport with participants.” 

UCCE farm advisor Dr. Franz Niederholzer leading calibration training section in Arbuckle, CA

UCCE specialist Dr. Peter Larbi leading calibration training section in Parlier, CA

The Impact

In all, 22 participants provided feedback on their learning for the combined Calibration Training sections for the Northern and Central California events. Overall, 100% reported “much” to “very much” learning from the combined Calibration Training sections indicating that they were very effective and provided participants with a great amount of learning. Likewise, 100% also indicated their intent to adopt the practices learned from the section. Looking at each section of the training, 82% reported learning “much” to “very much” from the “Sprayer parts review”, 100% the same for “Sprayer calibration basics and calculations”, 91% for “Sprayer speed determination with flagging”, 91% for “Sprayer air profile assessment and nozzle configuration”, 91% for “Flow rate measurement”, and 82% for “Spray coverage evaluation” (full breakdown of feedback by section in the graphic below). Additional written comments were mostly positive.

Combined evaluation results of the Calibration Training sections

The needs assessment conducted by Dr. Larbi for his Agricultural Application Engineering Program in 2019 showed that 56% of perennial specialty crop growers and applicators in the San Joaquin Valley used airblast sprayers, 12% used tower sprayers, 15% used electrostatic mist blowers, and 17% used other sprayers. Also, 22% calibrated their sprayers 10 or more times a year, 32% calibrated 4-6 times, and 46% calibrated only 1-3 times a year. According to the California Pesticide Use Report, in 2021, 456,802 pesticide applications delivered 34,323,828 lbs. of pesticide across 24,147,968 acres of almond orchards. This amounts to 75.14 lbs. per application or 1.42 lbs. per acre. If even 1% of the application was overapplied and another 1% was underapplied due to using uncalibrated sprayers in the year (a conservative guess if nearly half of applicators only calibrate 1-3 years times a year), then 686,477 lbs would have been misapplied leading to either reduced pest control or increased pesticide loading on the environment. This number is very significant considering that the situation does not apply to only almond production. Thus, by increasing the competency of California's almond crop protection workforce for properly calibrating sprayers as a best practice, UC ANR potentially improved environmental sustainability.

UCCE academics Dr. Niederholzer and Dr. Larbi have an extended collaboration in providing spray application and sprayer calibration training in both Northern and Central California since 2019. The results presented here exemplify the impact of such trainings. Expanding this collaboration to include industry stakeholders reaches other audiences, potentially new participants, and increases the extent of impact. UC ANR will continue to support California agriculture through such trainings and the dissemination of science-based information to promote operational efficiency and profitability.

UC ANR supports California's crop protection workforce to become more qualified through hands-on Airblast Sprayer Calibration Training. 100% of participants reported learning professional skills that also can improve the sustainability and profitability of California ag.

Dr. Peter Larbi teaching sprayer calibration basics during the Airblast Sprayer Calibration Training

The Issue

As a best practice in pesticide spray application, growers and pesticide applicators should calibrate their sprayers to ensure accurate application rates and compliance with the law as represented by pesticide labels. However, proper understanding of sprayer calibration objectives and steps is needed to avoid a false sense of accuracy using incorrect methods. Educating growers and applicators in calibration methods will therefore empower them to ensure the use of properly calibrated sprayers well-adjusted to the target canopy to minimize pesticide waste and drift loss.

How UC Delivers

A half-day “Airblast Sprayer Calibration Training” was conducted in November 2022 at the Kearney Agricultural Research and Extension (KARE) Center. The in-person extension education event was supported by a California Department of Pesticide Regulation (DPR) grant. It involved classroom and field exercises focused on axial airblast spray applications directed to tree and vine canopies. The training was instructed by Dr. Peter Ako Larbi and assisted by his postdoc scholar Dr. Abiodun Abioye, with logistical support from his Agricultural Application Engineering (AgAppE) Lab and KARE Center personnel. It covered the basic steps and calculations involved in sprayer calibration, with practical follow up via hands-on demonstrations in the field. The DPR approved 3.5 hours of continuing education credits in ‘Other' category for qualifying participants. Sixteen participants were in attendance consisting of growers, applicators/operators, pest control advisors/certified crop advisors, scientists/researchers, and others.

The training started with classroom instruction covering “Welcome, Introduction, and Purpose” (comprising an overview of spray application goals, spray application outcomes, and sprayer calibration and adjustment objectives) and “Sprayer calibration basics and calculations” by Dr. Larbi. It then transitioned to in-field setting in a citrus block in an interactive format allowing participants to interject with questions, comments, and observations. With active participant involvement, the field experience included a presentation on “Sprayer Equipment Parts/Nozzles” by Dr. Abioye, hands-on exercises covering the calibration steps led by Dr. Larbi, a wrap-up discussion and answering of additional questions, and ended by evaluating participant learning. Engaging participants in various hands-on activities corresponding to the recommended calibration steps was intended to reinforce their learning. The spray equipment was operated by KARE Center staff research associate Ryan Puckett.

“Really helped me understand calibration much better.”

 “Excellent speakers, demonstrators, trainers.” 

Postdoctoral scholar Dr. Abiodun Abioye speaking about sprayer equipment parts

UCCE specialist Dr. Peter Larbi leading hands-on experience.

 

Participants engaging in hands-on exercises during the training. Top left: Observing sprayer travel time in next row to determine travel speed. Top right: Observing and reviewing sprayer air profile to determine number of nozzles needed. Bottom left: Affixing tubes to nozzles for measuring spray liquid flow rate from nozzles. Bottom right: Measuring nozzle flow rate with automatic nozzle calibrators.

 

The Impact

The participants were fully engaged throughout the training, and all (100%) provided feedback on their learning. Overall, those who reported gaining “much” to “very much” learning are: 94% for “Welcome, Introduction, and Purpose”; 100% for “Sprayer calibration basics and calculations”; 100% for “Equipment: Sprayer parts/Nozzles”; and 100% for “Hands-on calibration exercise”. On average, 97% reported gaining such learning in the classroom portion and 100% in the field. Overall, 100% reported “much” to “very much” learning from the entire training, indicating that it was very effective and provided participants with a great amount of learning. Additional written comments were mostly positive, and many participants verbally expressed their appreciation for the thoroughness of the training.

 

Evaluation results of the Airblast Sprayer Calibration Training

Dr. Larbi and his AgAppE Program plan to continue providing similar trainings in the future on both ongoing and need bases to arm his clientele with science-based knowledge and skills that will promote their operational efficiency and profitability.

Dr. Larbi addressing a participant's question

According to the 2021 California Pesticide Use Report, 82,550,620 lbs. of pesticide was used in 941,751 applications for the top five (5) crops in all counties in the San Joaquin Valley covering 45,087,167 acres. Eighty-nine (89) percent of the quantity was applied on 39,742,883 acres of perennial specialty crops, which are the systems of primary focus for Dr. Larbi and his AgAppE program, amounting to 79.38 lbs. per application or 2.34 lbs per acre. Moreover, Dr. Larbi's 2019 Agricultural Application Engineering Program needs assessment revealed that only 22% of growers and applicators calibrated their sprayers 10 or more times a year, 32% calibrated 4-6 times, and 46% calibrated only 1-3 times a year. Hence, assuming a mere 1% of the application done in perennial specialty crop in 2021 was overapplied and another 1% was underapplied due to using uncalibrated sprayers, then 1,467,100 lbs would have been misapplied leading to either reduced pest control or increased pesticide loading on the environment. This number is very significant considering that the situation does not apply to only the top five crops. Thus, by increasing the competency of California's crop protection workforce for properly calibrating sprayers as a best practice, the AgAppE Program potentially increased workforce retention, improved environmental sustainability, and increased the profitability of growers.