- (Focus Area) Agriculture
- Author: Emily Kraus
Hello Small Farms Community! My name is Emily Kraus and I am excited to announce that I have joined the UCCE Small Farms team in Fresno. Back in June (2024), I made the treck to Fresno from Florida. I had a little time to settle in before beginning my new role here in July. Since then I have been BUSY trying to figure out how to serve the community of small farmers in the area. Please read on to learn a little more about me and my hopes for the program.
My Background
My journey began like many others, with one step out the door of my parents' home in Indiana. The first big stop was at Purdue University where I received my B.S. in Entomology, the study of insects! The projects I worked on there involved biological control of soybean aphid and genetic work on the human body louse. Both agricultural and medical entomology were interesting to me and I had a hard time deciding which to pursue. I ended up going to Kansas State University next where I completed my M.S. in entomology with a focus on mosquitoes. It turned out I didn't like being indoors all the time so I decided to join the U.S. Peace Corps as a Sustainable Agriculture Extension Agent. They sent me to Senegal West Africa! That was an amazing experience.
From there I decided to continue to pursue agriculture and worked briefly at Monsanto before going on to Louisiana State University. There I did my PhD work in rice production. I loved working on the universities rice farm and talking to rice growers at Extension meetings. Ultimately, I graduated and had to decide what to do next. I decided to do a postdoctoral fellowship at Rhodes University in South Africa. There I worked on biological control of invasive weeds. It was very interesting work. There are not many places where your field work might put you in a river with crocodiles and hippos!
When I came back to the U.S. I wanted to move to Florida to spend more time with my family. First, I worked at the Florida Department of Agriculture and Consumer Services (FDACS). This role also involved biological control of invasive pests. I learned about the Asian citrus psyllid and met a whole new group of farmers. After a few years I switched over to the University of Florida and spent two years in the Pesticide Information Office as an Extension Scientist. It was from this work that I learned all about becoming a certified pesticide applicator. The only problem was that there was no research opportunity in this position which is one of many reasons I wanted to become a Farm Advisor here in Fresno.
Getting Started in Fresno
It has taken me a couple of months to get going in this role. Many of you reading this know I am coming in after Ruth Dalquist-Willard. Due to her extensive success I have quite a large program to take over! I have been spending my time meeting the team and making connections with other organizations in the area. Also, I have made a point to get out on the farms. There is so much diversity in the small farms in this region and it seems it could take a lifetime to learn about them all.
As a team we intend to continue many of the projects that Ruth had going. These include investigating benefits of cover crops and compost, working with growers to pass food safety inspections, supporting growers with information on pesticide regulations, trouble-shooting various issues with water access and quality, and tracking the expansion of new pests like the Mexican Rice Borer. There is no shortage of things to do! As I learn more about the specialty crops and challenges our stakeholders face, I am designing new projects and will be keeping the team busy!
Looking Forward to Meeting You!
The most important part of getting started in this role is for me to meet our partners and stakeholders. Please reach out and introduce yourself! I will certainly be making the rounds to local farms and networking events, but don't hesitate to put yourself on my radar. The team here in Fresno is excited to continue to serve our stakeholders as I transition into this role. We want to hear about your concerns and figure out how we can continue to support small farms in Fresno and Madera counties, as well as contribute to projects across the state. I'm looking forward to meeting you!
/h2>/h2>/h2>/h2>
- Author: Ben A Faber
Get an airblast sprayer in the right condition so it can do its job right.
Read a summary of calibrating an airblast sprayer
https://www.sacvalleyorchards.com/almonds/foliar-diseases/pre-season-airblast-sprayer-calibration/
Using a calibration guide
https://ccag-eh.ucanr.edu/files/241473.pdf
Read it as written by Lynn and Franz
https://ucanr.edu/sites/ucexpertstalk/files/328586.pdf
or watch it as played by Peter
https://www.youtube.com/watch?v=c48h75tb-CY
or take the course on calibration for CEU credits
- Author: Kathy Keatley Garvey
YSP is a six-week summer residential program that introduces several dozen high-achieving high school students to original research within the fields of biological, agricultural, environmental, or the natural sciences.
The lab of nematologist Shahid Siddique, associate professor, UC Davis Department of Entomology and Nematology, mentored Anderson Van Wang, a 17-year-old senior at California City High School, Kern County, and Mason Walline, now 18, and a senior at Harvard-Westlake School, Los Angeles.
Anderson worked with doctoral student Veronica Casey of the Siddique lab to investigate the effects of bacterial supernatant to plant parasitic nematodes. Walline worked with Ching-Jung Lin, a doctoral student in the Siddique lab and the lab of Professor Gitta Coaker, Department to Plant Pathology, to transiently express nematode proteins in the plant system.
Also mentoring them were Siddique and lab members Bardo Castro Esparza, a postdoctoral fellow; and Alison Blundell, a doctoral candidate.
Each scholar receives five units of University Group Study Credit. All work is graded. Not only do they engage in university-level course work, attend lectures, and work on their projects, but they experience “the climate and culture of living and learning on a university campus,” according to YSP director Megan Bettis.
Mason won second-place honors in the research competition, the "YSP Summer Slam" (Elevator Pitch or short-version), competing with some 35 other students. His topic: “Advancing Transient Nematode Peptide Expression: A Pathway to Co-Immunoprecipitation Optimization." Said Lin: "He delivered a compelling two-minute presentation with a single slide. His expertise and professionalism were evident, and he was awarded second-place among the six finalists."
Neither plans a career as a nematologist, but what an amazing program and what an amazing experience.
“Working in Dr. Shahid Siddique's lab was an absolutely amazing experience," Anderson said.
“The lab environment was very high energy and upbeat," said Mason. "I'm so glad I was a temporary part of such a strong and inclusive community.”
And they learned a lot about nematodes.
Siddique defines plant-parasitic nematodes as "destructive pests causing losses of billions of dollars annually. Economic, health, and environmental considerations make natural host plant resistance a preferred strategy for nematode control, but there are limitations to this approach. In many cases, the resistance conferred by resistance genes is partial, and some of the nematodes are able to survive. Similarly, nematode resistance genes are often effective against only one or a few species, whereas plants are exposed to several pathogens in the field. Another concern is the emergence of pathotypes that can overcome resistance. In view of all these limitations, it is important to identify additional mechanisms and tools that can be used to develop novel and sustainable approaches to the management of nematodes."
The 2025 YSP summer program is set June 22-Aug. 2, with applications opening Jan. 15. High school students can apply at https://ysp-app.ucdavis.edu/.
- Author: Ben A Faber
There has been a recent expansion of Avocado Lace Bug into parts of the Carpinteria area. It was more or less located in the San Diego coastal area. It spreads mainly with people.......
Read about it at the UC-IPM website and the observations of Mark Hoddle, IPM Specialist at UC Riverside.
https://ipm.ucanr.edu/agriculture/avocado/avocado-lace-bug/#gsc.tab=0
- ALB does better in the slightly cooler more humid orchards in Oceanside when compared to the hotter inland Bonsall orchards.
- In the lab, under a fluctuating 24 hr temperate cycle similar to an avocado orchard in Escondido, optimal temps for development are a daily average of around 31-32oC (88-90oF)
- ALB life stage densities tend to be greater on leaves over June-Oct
- % leaf infestation measures (i.e., the proportion of sampled leaves with ALB lifestages) tend to be peak over fall-winter (Sept-Feb), but ALB densities on leaves are not as high as what are seen over June-Oct, there are basically more leaves with ALB and those per leaf densities are lower that numbers counted over June-Oct.
- Its hard to predict what the next season's ALB will be as lots of ALB are shed when leaves drop, but like persea mite, some manage to get back onto the new leaves to start the next round of infestations. Adults don't seem to be very flighty, well, at least they don't seem to exhibit mass flight activity that would suggest searching for new hosts as leaves deteriorate.
Keep your eyes open for a future edition of the CA Avocado Commission's magazine - From The Grove - for a more thorough discussion of the pest.
https://www.californiaavocadogrowers.com/publications/from-the-grove
images:
Adult
Adults, young, and fecal pellets
Leaf damage
- Author: Elizabeth J Fichtner
- Author: Carol Lovatt
The alternate bearing (AB) nature of olive is one of the top physiologically-driven challenges faced by olive growers. AB refers to the tree's habit of producing a heavy crop in one year followed by a light crop the next year. The heavy crop is referred to as the “ON crop,” which is characterized by large yields with small size fruit that may mature late and have reduced commercial value due to size. Conversely, the “OFF crop” has characteristically low yields with large sized fruit that may not be cost effective to harvest. AB adversely affects the consistency of the fruit supply, thus having a negative economic impact on every step within the production chain from farm to consumer. Because mitigation of AB can best be achieved by management of crop load, UC researchers have conducted recent studies evaluating the efficacy of a new chemical flower thinning strategy using naphthaleneactic acid (NAA) (Figure 1) applied at full bloom to only on side of the tree annually or biennially to reduce the severity of AB and maintain higher annual yields of commercially valuable size fruit.
There are currently four known mechanisms by which the ON crop reduces flowering and fruit number to contribute to AB of ‘Manzanillo' table olive orchards. The first mechanism of AB is the suppression of summer vegetative shoot growth by the current crop (Figure 1). Flowers and fruit on olive are borne on one year-old shoots; consequently, the vegetative growth in the current year provides the nodes at which inflorescences form in the subsequent spring. Research studies conducted in Tulare County California have demonstrated that the fruit's suppression of vegetative growth is irreversible after pit hardening. As a result, crop management strategies designed to reduce the current season's crop must be implemented by June to promote summer vegetative growth and increase return bloom the following year. The second mechanism of AB is inhibition of floral development (typically initiated in July) by the current season's crop. The third mechanism of AB is the inhibition of spring bud break. As a result of bud break inhibition, even floral buds that have formed may not open at bloom. Last, the current season's crop causes the abscission of floral buds. Since the OFF crop has an effect opposite to that of the ON crop, once AB is initiated in an olive tree, cycles of ON and OFF floral intensity and cropping are perpetuated by the opposing effects of high and low crop loads on these mechanisms.
Historically, olive growers have used NAA, a plant growth regulator, as a fruit thinning agent to reduce the current season's fruit load. Upon application, NAA is absorbed by leaves and developing fruit and is translocated to the peduncle where it incites an abscission layer at the point of attachment to the stem. As an olive fruit thinning agent, NAA is typically applied 12-18 days after full bloom, i.e., during fruit set. Treatments are made with an NAA ammonium salt product, such as Liqui-Stik Concentrate (Loveland Products) applied as a dilute spray (300-500 gallons per acre). Chemical thinning with NAA can be risky; too early an application may result in overthinning, whereas too late an application may not thin sufficiently. Additionally, hot temperatures (> 100°F) within one week of application may enhance the efficacy of NAA resulting in excess thinning. Due to the greater risk of spring heat waves in the south, chemical thinning has been more commonly utilized by table olive growers in the Sacramento Valley than in the southern San Joaquin Valley.
With support from the California Olive Committee, researchers have been evaluating the use of NAA at full bloom (rather than 12-18 days after bloom) as a crop management tool to reduce the severity of AB, which is measured as alternate bearing index (ABI) on a scale from 0 (no AB) to 1 (total AB, crop one year, no crop the other year). These studies tested a full bloom NAA application to one side of the tree with the goal of eliminating crop on one side of the canopy (Figure 2) while maintaining crop on the opposite side. Annual and biennial applications of NAA to just one side of the tree were compared. To implement the annual NAA application strategy in a commercial orchard, growers would apply NAA to one side of the tree at full bloom in year 1, then on the other side of the tree in year 2. In the biennial strategy for NAA application, there would be a year of rest (no treatment) between the application to one side of the tree in year 1 and the other side in year 3.
After 4 years of research, NAA application either annually or biennially at full bloom did not affect cumulative total yield. However, full bloom NAA applications to one side of the tree significantly reduced the severity of AB from near total AB (ABI = 0.94) for the untreated ON/OFF control trees by 20% when applied annually and 38% when applied biennially. The results indicate that annual total yields were more uniform from year to year, especially for trees treated biennially, which improves the economics of all steps in the production chain from farm to consumer.
In addition, both annual and biennial applications of NAA to one side of the tree at full bloom had positive effects on the yield of commercially valuable size (CVS) fruit (medium plus large) compared to the untreated ON/OFF control trees. Biennial NAA application at full bloom reduced the ABI for CVS fruit 43% compared to the untreated control trees, whereas annual NAA application at full bloom only reduced the ABI for CVS by 12.5%. Importantly, application of NAA at full bloom to one side of the tree biennially resulted in 40% greater cumulative yields of medium plus large fruit than untreated control trees, with annual treatment increasing yield of medium plus large fruit only 20%. The increased and more uniform yields of CVS fruit resulting from biennial NAA application at full bloom to one side of the provide growers with greater, more reliable annual income. Moreover, biennial application of NAA (once every three years) is half the cost of annual NAA application. Since NAA is applied to only one side of the tree at full bloom, for which total removal of the crop is desired, the risk of over thinning with NAA is eliminated in this strategy compared to the standard practice of applying NAA to the whole tree during fruit set. Whereas a grower must decide to treat once every three years based on floral intensity and without knowledge of the year's fruit set, the fact that only one side of the tree is treated lessens the effect of a subsequent poor set. The NAA standard practice provides the grower a window of 12-18 days after full bloom to evaluate fruit set when deciding to treat. If the grower sprays NAA according to the standard practice and set is subsequently negatively impacted (potentially by even NAA itself interacting with high temperatures), the whole tree will be affected.
The results of this research demonstrate the potential value of NAA applied at full bloom to shift the crop load to one side of the tree and then the other side biennially. This technique essentially creates a bearing and non-bearing side to each tree, allowing for unsuppressed vegetative growth on the treated side and documents the need for a rest period with no NAA application until year 3 to allow the tree to fully recover. Biennial application of NAA at full bloom to one side of ‘Manzanillo' olive trees successfully reduced the severity of AB and increased yields of commercially valuable size olive fruit better than annual application of NAA or the untreated ON/OFF control trees. The use of NAA at bloom to mitigate AB warrants further investigation. Researchers are also actively investigating the use of pruning 28 days after full bloom to only on side of the tree annually or biennially as a means of mitigating AB to achieve consistent yields of commercially valuable size fruit.