- (Focus Area) Agriculture
- Author: Sandipa Gautam
Upcoming Citrus Extension Outreach Meetings at LREC
August 20, 2024. Register here for AAIE Organized Citrus Roundtable for SJV growers: This is an opportunity for citrus pest control advisors to get together and talk about how they manage pests. The round table will discuss Ant Control, ACP, Thrips, Red Scale, Mealybug, Weed management, current regulations and pest management problems citrus pest control advisors have had. UCANR's Dr. Sandipa Gautam, Cooperative Extension Area Citrus IPM Advisor, David Haviland, Entomology and Pest Management Farm Advisor, Jorge Antonio Angeles, Weed Management Advisor, Dr. Bodil Cass, UCR Subtropical crops Specialist, and Chris Greer Assistant Ag Commissioner, Tulare County will be presenting at this meeting.
September 24, 2024: Register here for Citricola Scale Field Day: Citricola scale has been a problem in year 2024. This 2 hour event will focus on teaching PCAs on pest identification, monitoring, and best management practices manage citricola scale.
October 2, 2024: Register here for California red scale and its natural enemies workshop. A day dedicated to California red scale and its natural enemies is back! This hands-on workshop at Lindcove will teach PCAs how to recognize the various life stages of California red scale and their parasites with dedicated time to work with each life stage. With this knowledge PCAs can determine the level of parasitism of California red scale in their citrus orchards and make better decisions about scale control tactics. Seat is limited to 30 students.
October 9, 2024: Register here for Fall Citrus Meeting at Lindcove. Are you looking for one meeting where you can learn about various issues in citrus production? UC Researchers bring to you a Fall Citrus Meeting at Lindcove Research and Extension Center on October 9, 2024. This meeting will cover nutrient management and irrigation, insect pest, disease, weed management and regulatory pest and top issues and regulations followed by a group discussion to identify grower needs pertaining to various topics.
September 11, 2024: Register here for “Workshop on the Biology and Identification of Phytoseiid Predatory Mites in Agriculture” This workshop will teach students about the importance of predatory mites in agricultural crops and the basics of how to identify them to species level. Each student will have their own phase contrast microscope and access to a set of slide-mounted specimens to work through “The Key to Genera of Phytoseiidae Found on Crop Plants in California”. Learn from the experts – Dr. Beth Grafton-Cardwell will be leading the class with David Haviland. Seat is limited to 30 students. Full Agenda attached. This workshop will be held at Kearney REC, 9240 S. Riverbend Avenue, Exeter, CA.
Attached Files CRS Annoucement October 2 2024
Local Citrus Round Table Agenda AAIE
Workshop on the Biology and Identification of Phytoseiid Predatory Mites in Agriculture
Citricola Scale Field Day Announcement - September 24 2024
Fall Citrus Meeting at Lindcove
- Author: Daniel K Macon
Folks new to the world of working livestock guardian dogs (LGDs), whether they are producers or dog aficionados, often ask, “What's the best breed?” or “What breed is your dog?” I usually begin my answer with a joke: “He's a North American BWD – Big White Dog!” I then go on to explain that all of my successful dogs have usually been a mix of breeds, and that I put more emphasis on the working abilities of my dogs' parents and on desirable phenological traits (like a short coat) than I do on selecting specific breeds. My most recent dogs have all been mixes – Maremma-Anatolian, or Pyrnees-Akbash, for example. And I suspect that most working LGDs here in North America are not purebred – dogs that work in a production setting are also those who get to reproduce, regardless of whether they are purebred. Sometimes this breeding is intentional! A new paper published in iScience sheds light on the varied ancestries of modern livestock guardian dogs.
In “Multiple ancestries and shared gene flow among modern livestock guarding dogs,” the authors generated genome-wide single nucleotide polymorphism (SNP) data from 304 LGDs and combined it with public-genomic data from 2183 modern and 22 ancient dogs. Their analysis suggests shared ancestry and extensive gene flow among modern LGD breeds, which they attribute to historic livestock migrations.
The authors developed genome-wide SNP data from specific LGD breeds extended geographically from the Iberian Peninsula, through Europe, Italy, the Balkans, Western Asia, and Eastern Asia. While much of their analysis goes beyond my very simplistic understanding of genetics, their findings “strongly support the hypothesis that modern LGD breeds from East Asia and the rest of Eurasia are part of two lineages that have evolved independently for millennia.” I find this fascinating – humans who were raising livestock on rangelands in separate regions of the planet looked to dogs as protectors of their livestock! And they developed separate genetic lines with similar physical and behavioral traits!
Transhumance migration – the seasonal movement of people and livestock between high- and lowlands (following the feed) – seems to have played a significant role in the genetic flow between regionally-specificLGD breeds.Transhumance seems to have occurred across many cultures and geographic regions (and still persists today). The nomadic herders of the Mongolian steppes and the open-range sheep outfits of theIntermountain West would recognize eachother's day-to-day work.
Similar to today's Big White Dog breeding strategies, I can imagine multiple family groups taking their sheep and goats along adjacent (or overlapping) migration routes into (and back from) the high country. Perhaps my modern notions of livestock ownership doesn't exactly apply, but I suspect that each family would have tried to keep their livestock separate from the adjacent flocks. But the dogs would have mixed on the margins between these flocks! And they would have reproduced.
In his essay, “Let the Farm Judge,” Wendell Berry describes the powers of observation and adaptation employed by thousands of shepherds over thousands of years on the British Isles that allowed the development of 80 distinct sheep breeds and cross-breeds on a group of islands smaller than California. I can imagine similar observations and adaptations leading to LGD breeds in a transhumance system of livestock production. The dogs that stayed with their flocks – that protected livestock from wolves, brown bears, big cats, other dogs, and even 2-legged human predators – were noted by their owners. And allowed to reproduce – either with other dogs guarding the same flock, or with dogs guarding adjacent herds. If the offspring of these couplings didn't work, they left the gene pool.
The paper notes that reproductive management has not always been intentional in LGD breeds (nor is it today, for that matter). The authors' genetic analyses suggest that there is ongoing gene flow between LGD breeds and free-ranging dogs in specific geographic regions, stating, “Whereas breed clubs and registering bodies forbid dog owners from crossbreeding to dogs from other breeds for the purpose of maintaining traits, such restrictions are not imposed on working landrace populations and, as such, may be challenging to maintain in working dogs frequently left unattended.” In other words, dogs will be dogs – especially LGDs!
Finally, the authors discuss the relatively recent transition of some LGD breeds from working landraces to a registered system of pedigreed pets (notably the Great Pyrenees and Kuvasz breeds). In comparing pet dog genetics with those of working lines, the authors found a higher degree of inbreeding in pet dogs, likely reflective of the use of a handful of popular pedigreed sires.
These last two findings, as the authors indicate, suggest that selecting LGDs for specific guarding behaviors (attentiveness to surroundings, lack of prey drive, or submissiveness to livestock) and other factors (likelihood of roaming, or lack of aggressiveness towards people) may not be entirely (or even mostly) genetically based. In other words, reproductive isolation (that is, only breeding working LGDs to other working LGDs) may not the core mechanism for maintaining the specialized skills of LGDs. Assessing the behavior and performance of a prospective LGD during the puppy selection process becomes even more critical, given these findings – as does the bonding process. While I'm not suggesting that a well-managed bonding process will overcome poorly bred LGDs, this paper seems to confirm that genetics is just one part of a very complicated puzzle! It was a fascinating read!
Coutinho-Lima, D., et al., "Multiple ancestries and shared gene flow among modern livestock guarding dogs." iScience. 110396. August 16, 2024.
- Author: Ben A Faber
In a recent meeting the topic of where to go for irrigation information came up. Well there's no substitute for attending a class in irrigation, such as offered at Cal Poly SLO (http://www.itrc.org/classes/iseclass.htm ,
but here's some written sources to get you started thinking.
http://ciwr.ucanr.edu/california_drought_expertise/droughttips/
http://www.salinitymanagement.org/Salinity%20Management%20Guide/ei/ei_1.html
http://www.avocadosource.com/tools/IrrigationCalculator.asp
http://lawr.ucdavis.edu/cooperative-extension/irrigation/manuals
http://lawr.ucdavis.edu/cooperative-extension/irrigation/drought-tips
http://biomet.ucdavis.edu/index.php/evapotranspiration-mainmenu-32
- Author: Ben A Faber
Farm Advisor UCCE Ventura County
Plants, therefore avocados, go through different growth stages, so called phenological stages, regular periods where they grow and differentiate from seed to various vegetative stages, flowering and finally seed production. Avocado has a preset pattern of phenology that occurs depending on variety and where it is grown, driven by light, temperature, water availability and often by different stresses, such as cold, heat, and heavy or light crop load.
The successive stages of avocado phenology are demonstrated in the photomontage below, from bud break to harvestable fruit:
Main phenological growth stages of ‘Hass' avocado according to the extended BBCH scale. From: http://avocadosource.com/journals/elsevier/scientiahort_2013_164_434-439.pdf
And, depending on where in California the avocado is growing, the latitude, or on what side of the slope (in the shade or full sun, on the top of the slope, etc.), the tree will go through these successive stages at different times of the year, offset by weeks or even months. A general plan for the California coastal region was developed from accumulated experiences and tests by a variety of groups and is shown below:
Research-based information that allows producers to anticipate the regionally appropriate times for major phenological evets is limited in California. From work conducted at South Coast Research and Extension Center in Irvine, the onset of flowering in early March extends into May, normally, and the main fruit set period is between mid-April and May. In later work from the same location, a mean beginning bloom date for “on” and “off” crop years differed between Julian date 66 (March 7) and 80 (March 21), respectively. From avocado research in Carpinteria, flower abscission (as a measure of bloom) during “on” and “off' crop years peaked on two different Julian dates, (May 4 and June 2). Mid-June has been reported as the middle of the commercial ‘Hass” season for the Irvine area. Harvest in Santa Barbara and San Luis Obispo Countries may just be staring in mid-June and continue through November in the most northern growing areas.
Difference in crop development impact the timing of cultural practices, such as fertilization, irrigation, phytophthora treatment, pollination and gibberellin sprays. For instance, nitrogen fertilization is often recommended by month of the year, rather than growth stage of the tree. Several recent efforts indicated that the timing of nitrogen fertilizer may have significant impacts on yield and that two times the fertilizer rates in April and November may result in substantial yield increase. Available information indicates the April timing might correspond to fruit set for the Irvine area compared to early bloom for Santa Barbara and San Luis. By November, Irvine's current year's crop may have been harvested three months previously. In San Luis Obispo, harvest may have just ended. So just going by date is insufficient for guiding many horticultural activities.
California's trees often have two crops maturing at the same time. It becomes especially pronounced the further north the production. The management of multiple crops on each tree becomes more important and more confusing as the length of time the fruit remains on the tree. Carrying two and even three loads of crop increases the potential for alternate bearing. Reduction in alternate bearing has been determined to be an important strategic requirement for California's growers. Understanding the impacts of cultural practices on alternate bearing is important. For example, the chart below demonstrates a stylized calendar of the avocado growth cycle for California. Rate and application timing of nitrogen as predicted by the Avocado Nitrogen Model proposed by Rosecrance et al. (2013 and Calculator) are noted for a 15,000 per acre yield outcome. The “on” year suggests nitrogen rate for the late fruit growth/harvest/summer and fall flush period is 15 lbs. This application coincides with the fruit set timing for 16 lbs of N for the “off” bloom crop during the later bloom/fruit set/spring shoot growth phase. Rates and timings to support these crops ought then be combined and represent the 2X fertilizer rate that Lovatt (2001) found to have significant effects on yields.
Calendar of avocado growth cycles with both “on” and “off” years represented when they overlap, and suggested nitrogen fertilization timings and amounts.
Taking into account the actual phenology, what is happening in your trees, then is important for assessing when to make N applications. In the winter and spring of 2023, it seems like everything was on a different cycle. Thrips delayed their appearance, flowering was erratic. Honeybees seemed to have found somewhere else to hang out, because they were not flying in the avocado trees. And then suddenly, we had some fruit set in Ventura in late June. This is a really clear example of the problem of following a cookbook to farming avocados. The point here is that just going by the calendar is not going to meet the needs of the tree. The phenological stages of the tree in your environment needs to be taken into consideration.
Notes:
Lovatt, C.J. 2001 Properly Timed Soilapplied Nitrogen Fertilizer Increases Yield and Fruit Size of ‘Hass' Avocado. J. Amer. Soc. Hort. Sci. 126(5): 555?559.
Rosecrance, R., Lovatt, C.J., 2013. Management tools for fertilization of the 'Hass' avocado. FREP final report.
Calculator: https://rrosecrance.yourweb.csuchico.edu/Model/AvoModel/Avo2NKModel.html
- Author: Saoimanu Sope
UCCE scientists study feasibility of specialty crops for small urban growers
The vacant lots around your neighborhood could be growing fruits and vegetables and making local produce more accessible – while reducing energy needed to transport and distribute the food. Could turning those empty lots into small farms also become opportunities for economic development?
To answer this question, a team of researchers from University of California Cooperative Extension in San Diego County are investigating the economic feasibility of growing high-value specialty crops in urban settings like vacant lots. The project – led by Eric Middleton, UCCE integrated pest management advisor for San Diego, Orange and Los Angeles counties – is currently in progress at The Flower Fields in Carlsbad, a seasonal attraction for locals and tourists.
Tucked away in the back of the field is the Small-Scale Urban Ag Demonstration Site where Middleton and his team established a small farm on approximately 17,000 square feet, starting fall 2023. Funded by the U.S. Department of Agriculture National Institute of Food and Agriculture, the farm is designed to evaluate containerized production both outdoors and under high tunnels.
Growers don't necessarily need land, just space
High tunnels, also referred to as hoop houses, are semi-permanent structures that act similarly to greenhouses in providing a controlled environment. For the experiment, Middleton will compare cost, effort and durability of two types of high tunnels: one made of steel and the other out of PVC pipes.
“We want to give interested growers information on as many options as we can,” said Middleton, who explained that the project is motivated by the challenges of urban settings, including limited space and lack of arable land.
In the trial, they are growing turmeric, ginger and blueberries. The high-value crops were selected because of their potential to earn a profit. Data evaluating plant variety, soil mix, fertilizer, growth performance, yield and pest and disease pressures will be collected and reported when the project concludes in 2026.
As the crops develop in containers – blueberries in pots and turmeric and ginger in grow bags – Middleton pointed out the mobility aspect of the study, noting that growers don't necessarily need land, just space.
Whether it's a backyard or a rooftop, containerized production means easier transport, especially since vacant land doesn't always remain vacant forever and urban lots may often need soil remediation. Growing in containers solves the anticipated problem of having to relocate.
Where to set up shop in San Diego County
Jan Gonzales, project coordinator and community education supervisor for UCCE San Diego County, is leading the effort to identify available urban land in San Diego County as well as the policies and procedures for growers to access these spaces.
Gonzales is collaborating with community members who are working on similar projects to identify space for prospective growers.
“This has been done before for different objectives and for specific areas in the region, but the information was either project-specific and not publicly available, or not easy to find,” Gonzales said.
Having spoken with people associated with previous or ongoing agricultural land mapping projects, Gonzales has agreed to coordinate and facilitate an advisory work group to discuss areas of potential collaboration and develop project efficiencies. She anticipates holding the first group meeting before the end of the summer.
A production guide to help community members re-create the project
The ideal audience for a study like this is anyone who wants to grow specialty crops, according to Lindsey Pedroncelli, interim director of UC South Coast Research and Extension Center in Irvine, who worked on the project alongside Middleton when she was a staff research associate with UCCE San Diego.
“If you're a new grower or a grower who wants to diversify your crop production, what we're learning here can be applied to you,” said Pedroncelli.
Pedroncelli has been instrumental in bringing the experiment to life and documenting its step-by-step workflow thus far. The production guide, which is being created as the study unfolds, will include instructions detailing how to replicate the experiment from the ground up. Currently, it contains information on how to design your farm, the materials to buy, building structures, irrigation setup and crop management.
The most intriguing open question, whether the operation is profitable, is the driving force behind the production guide and will certainly be addressed, Pedroncelli said.
Book a tour and visit the farm
When visiting the farm, you'll encounter three varieties of blueberries: Star, Snowchaser and Misty. Snowchaser has been a top producer since it was planted in January, but the variety is known to be an early season producer.
Using only one variety of each, the turmeric and ginger were planted in late March-early April. With some unanticipated cold weather in San Diego County, both crops struggled when transitioning out of dormancy, leading to very slow progress, which the team is still navigating today.
Visually, Middleton and his team have noticed differences between the crops growing under the high tunnels versus those grown outdoors, although the data has not been analyzed to confirm or explain notable differences.
Attempting to demonstrate how to profitably grow high-value crops in urban settings using limited space and resources, Pedroncelli said she hopes this study will also encourage people to grow culturally significant crops for their communities.
To tour the Small-Scale Urban Ag Demonstration Site at The Flower Fields in Carlsbad, email Eric Middleton at egmiddleton@ucanr.edu with "Urban Agriculture Demonstration Site Tour" in the subject line.
To learn more about the project and its progress, visit https://ucanr.edu/sites/socalIPM/Small_Scale_Urban_Agriculture_Project_/.
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