- (Public Value) UCANR: Protecting California's natural resources
This is a recent USDA report on the state of the Mexican citrus industry. It's interesting to hear how this industry is doing faced with HLB. And Drought.
Significant and ongoing drought conditions in many citrus-producing states have resulted in a reduction in all citrus production, compared to the previous report, with orange production forecast to fall forty-five percent. As a result of low orange supplies for processing, fresh concentrated orange juice exports to the United States are expected to fall to nearly half of the MY 2018/19 export level. COVID-19 sanitary measures are affecting domestic consumption of citrus fruit and juice, as many hotels and restaurants have been closed since mid-March. Full consumption effects will depend on the length of ‘stay at home' orders and the long term effect on the hotel and restaurant industries.
Drought and high temperatures
Orange production is estimated at 2,53 million tons for 2019/2020. That is 45% less than previous estimates. It is also the lowest expected harvest since the early 90s. This estimate is based on grower data and discussions with sector representatives.
The persistent drought and high temperatures have had a more drastic effect on orange production that other citrus. That is because many of the orange groves are older and need more energy to produce fruit. Many small farmers also lack irrigation technology. They practice bad pest control too, which compounds cultivation issues. Large-scale growers mostly have several irrigation mechanisms. They use fertilizers and apply other mitigating measures too. These include leaving weeds growing around the tree trunks. This retains moisture.
There have been intense temperatures and lack of rain throughout the growing season. That has resulted in a widespread decline in the orange's quality. Most fruit in the orange-growing region are smaller and of lower quality. In the state of Veracruz, October and November 2019 were the hottest months.
It usually rains throughout the growing season. However, this season, it was concentrated in two months. That resulted in a shorter growing season. The last flowering cycle indicates the harvest's end. This was between December and March. In Veracruz, oranges can usually be harvested until June.
Mexico is typically the world's second-largest producer of limes, and the fruit is the second-largest planted citrus crop in Mexico after oranges. While drought has affected lemon and lime production throughout the country, they have not been as affected as oranges. This can be attributed to newer plants and more widely available irrigation infrastructure. Persian lime trees in Veracruz are newer and more efficient, with 12 blooms, or harvests per year.The Post planted area for all limes and lemons in MY 2019/20 is forecast at 208,000 hectares, similar to previous MY; however, harvested area is expected to decrease eight percent due drought and high temperatures that caused some producers to abandon harvest or replant trees.
Italian lemons (Eureka) are grown in the states of Tamaulipas, Yucatan, San Luis Potosi, Colima, and Nuevo Leon. According to producers, there are currently attempts to grow the Italian lemon in the state of Veracruz with very good results. According to official sources, for MY 2018/19, production of Italian lemons was 131,469 MT on about 9,264 hectares. Sources indicate that lemon supplies for MY 209/20 are tight, and prices are high.
As with other citrus-producing countries, Mexico is facing issues with citrus greening, or Huanglongbing (HLB). The disease, caused by bacteria introduced by psyllids, makes citrus trees produce misshapen, partially green fruit (taste is typically not affected, but has no marketability for fresh consumption). Mexico's first detection was in 2009, and since then, the National Service of Agricultural Food Safety and Quality (SENASICA) has implemented a monitoring program for the disease. HLB has been detected throughout Mexico in citrus production areas. Producing states, including Veracruz, Tamaulipas, San Luis Potosi, and Nuevo Leon, have had HLB detections. In 2019, Baja California had HLB positive detections along the California/Mexico border region
On the map, dark outlined areas are where citrus is grown and yellow shaded is drought area.
From Fox Weather by way of CA Avocado Commission, hot weather is forecast for mid- to late- June
This is a time to make sure that trees are adequately hydrated prior to the heat spell. Once trees start losing water through transpiration, it's hard for them to absorb water and heat stress and sunburn damage can result. The trees need to be fully water, so that they can continue to transpire to cool themselves during the heat spells.
And don't forget people in the field:
- Be sure shade is available on demand when the temperature is below 80 degrees F, shade must be provided at all times when the temperature exceeds 80 degrees F, as close as practicable to where employees are working;
- Shade must be provided to all employees on a rest or meal break,except those who choose to take a meal break elsewhere (editor's note: provision of shade as usual may not be consistent with social distancing recommended by various COVID-19 guidance; ag employers implementing heat illness shade requirements can ensure adequate shade consistent with social distancing requirements by staggering meal and rest breaks, but additional shade may be necessary);
- Fresh, pure, and suitably cool water must be made available in sufficient quantities (replenishment is permissible) to allow each employee to drink one quart per hour;
- Water is to be provided as close as practicable to location of work;
- Employees must be trained about heat illness and the Cal/OSHA Heat Illness Prevention (HIP) Standard before they work in conditions where they might be exposed to heat;
- Supervisors must be additionally trained in HIP compliance procedures, emergency responses, and ensuring effective communication to facilitate emergency response.
- A written copy of your HIP program in English and the language understood by the majority of the employees and be available to employees and Cal/OSHA inspectors on request — this is the most frequently-cited part of the HIP standard — and probably the most easily-avoided HIP citation!
- Remember: When temperatures exceed 95 degrees, employers must implement “high heat” procedures, including a mandatory 10 minute break every two hours (meal and rest periods can serve as these breaks, but if employees work beyond eight hours or waive meal or rest periods, you must still ensure the mandatory rest break occurs).
30-Day Weather Outlook for May 31, 2020, to June 22, 2020
Summary- The prevailing pattern is a high pressure ridge from N California westsouthwest or southwestward. Cold fronts coming S through California will tend to extend southwestward from southcentral-S California to the area SW – W of S California.
A long-lived pattern of troughing or low pressure will continue from southwest of Central California to about 25N then extend west toward Hawaii.
The MJO is showing a slow increase in activity over the next two weeks.
CFSDailyAI and CFSv2 suggest some rains primarily in northern California and the Sierras, and into Siskiyou Mountains and southern Oregon at times.
It is early for monsoonal showers and thunderstorms (TSTMS). However, the presence of upper lows may begin to bring tropical moisture northward into SOCAL and the Sierras, despite the lack of a usual summer monsoonal pattern.
Potential Dates of Precipitation (from Fox Weather's CFSDAILYAI system):
Salinas Valley-San Luis Obispo Co- S SierraNV:
Salinas Valley Showers: 6/2-3. Hot spells 6/4, 6/8-9, 6/11-12, 6/14-17, 6/22-27.
San Luis Ob/Edna: Hot spells 6/6, 6/9, 6/12, 6/15-17, 6/20-27th, 7/1.
Southern California Citrus/Avocado Area, San Luis Obispo Co to San Diego Co:
Southern California Citrus/Avocado Area: May 31-June 15.
Santa Barbara, Ventura to San Diego Co: No rainfall of consequence.
Santa Barbara Co: 6/6, 6/12. 6/16-17th, 6/22-26th.
Ventura Co: Hot 6/16-17th, 6/22-26th.
San Diego/Orange: Hot 6/16-17, 6/22-26.
Summary – June 15 – July 15… In Northern and Central California, Hottest: 6/14-17, 6/22,27, 7/1-2.
San Luis Obispo Co... Hottest periods 6/15-17, 6/22-27.
Southern California… Shallow marine layer and hot inland. Hottest: 6/16-17, 6/22-26, 7/1-3.
Seasonal Outlook July 15 – August 31... Northern and Central California overall pattern…. Near normal rainfall (minimal). Above normal temperatures occur during all of July and all of August. Usual thunderstorms (TSTMS) in the central and N Sierra and Plateau.
Southern California: San Luis Obispo Co, Santa Barbara Co, and Ventura to San Diego Counties east through Los Angeles to San Bernardino, Riverside and Imperial Counties…. Our latest guidance is suggesting a hot period in N and Northcentral California during mid-July, but near normal behavior of the marine layer at the SOCAL coast and valley areas. Although cloud amounts should be about normal, temperatures will drift above normal due to warmer sea surface off SOCAL and Baja. Weak troughs and upper lows will intermittently develop and deepen the marine layer as is normal for summer.
Looking further ahead into Sept – Nov, Dry and persistently warmer than normal conditions develop during the late Sept through Nov Santa Ana season.
Alan Fox...Fox Weather, LLC
Copyright © 2020, Fox Weather, LLC, Used by permission.
The news stories and social media comments about the Asian giant hornet detected last year in British Columbia and Washington state and labeled “the murder hornet,” are drawing the ire of entomologists throughout the world.
And well they should.
UC Davis wasp expert and researcher Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology, UC Davis Department of Entomology and Nematology, called the name "ridiculous" and said "it's no more likely to sting and kill a human than a honey bee." (See Bug Squad blog)
Lynn Kimsey, director of the Bohart Museum of Entomology, UC Davis, shows a queen Asian giant hornet, one of 20 in the Bohart's global collection. The largest in the collection, it is about an inch and a half long, she said.
Kimsey, a two-term past president of the International Society of Hymenopterists, told us yesterday that “Actually it's less likely, as honey bee venom packs quite a punch and it is exclusively designed to defend against vertebrates."
“The colony everyone is hyperventilating over was actually found on Vancouver Island, British Columbia, last September when it was destroyed and then a single, dead hornet was found in December in Blaine, Wash.,” Kimsey said. “There is no evidence that there are any more hornets in the vicinity of Vancouver or anywhere else on the West Coast.”
A colony of the Asian giant hornet (AGH), Vespa mandarinia, was found and destroyed Sept. 18, 2019 in Nanaimo, Vancouver Island, and the single dead hornet was found Dec. 8, 2019 in Blaine.
These were the first detections of this species in North America, and no, the so-called "murder hornets" are not out to get us. They're not out to kill you. They're not taking over the world. (Expect some upcoming horror movies, though!)
Twenty Asian giant hornet (AGH) specimens are housed in the Bohart Museum of Entomology, home of a global collection of nearly 8 million species. The largest AGH, a queen, measures about an inch and a half long, Kimsey said. She's never seen any larger than that.
Meanwhile, entomologists are bemoaning the name, "murder hornet" and the sensationalism and fear-mongering ensuing. Apparently the name originated with a Japanese researcher; out of the translation came "murder hornet."
“It's a bloody dumpster fire,” said entomology advocate, traveler and photographer Stephane De Greef, administrator of a newly created Facebook page, “Is This a Murder Hornet?”
“Some poorly-worded media reports about Asian giant hornets have triggered a veritable avalanche of nonsense online, but I can help set the record straight, wrote senior museum scientist and hymenopterist Douglas Yanega of UC Riverside Entomology Research Museum.
“One colony was found and exterminated in Nanaimo on Vancouver Island in September of 2019, with a few sightings associated,” Yanega wrote. “One wasp believed to be from that colony was found--dead--on the U.S. side of the border near Nanaimo in December. Right now, all the authorities are doing is asking people to keep their eyes peeled JUST IN CASE there were queens that escaped the destruction of the Nanaimo nest, and established their own nests nearby. I was one of the authorities brought in to consult on this case, and to my knowledge there have not been any sightings in 2020 that would suggest the eradication attempt was unsuccessful. Put bluntly, as far as we know, there are no Asian giant hornets alive in either the U.S. or Canada as of 2020, and if there are, then they would be in the immediate vicinity of Vancouver Island (about a 50 mile radius or so).”
Want to know more about them? Read the fact sheet published by Washington State University Extension. It's the work of the husband-wife team of Susan Cobey, bee breeder-geneticist and Timothy Lawrence, county director of Island County Extension (both formerly of UC Davis), and also Mike Jensen, county director of Pend Oreille. (See https://bit.ly/2SA3TxS)
“It is critical that we identify, trap, and attempt to eliminate this new pest before it becomes established and widespread,” they wrote. “Attempts to contain the spread and eradication of this invasive insect will be most effective in trapping queens during early spring before their nests become established. Finding the nests can be a bit of a challenge. Their nests are typically in the ground though they can also be found under overhangs and within wall voids. The AGH is a strong flier and often will fly up and away and have an extensive flight range. Thus tracking can be difficult.”
They advise residents to “proceed with extreme caution and contact WSDA immediately. Do not try to exterminate the nest yourself.”
The sensationalism on the media is a concern, said Lawrence, "but...we need to find out just how extensive this infestation is."
Facebook users are posting images of so-called Asian giant hornets that are actually such species as cicada killers, European hornets, southern yellow jacket queens, sawflies, hoverflies, a beetle, and even a moth.
“Yes, it is possible this species could establish,” wrote Sloan Tomlinson, a parasitoid wasp specialist and educator. “Has it yet? No. Until concrete evidence is presented about any further establishment by this species, it's simply conjecture. Additionally, even IF this species is established, their infamy is overhyped and sensationalized. In Japan they do indeed kill around 30 people a year. Around 40 people are killed annually in the US by domestic dogs.”
Doctoral candidate and researcher Ellie Field of Iowa State University wrote on Facebook that “the murder hornet articles are making the rounds quickly and they seem to be doing more harm than good. Yes, it is awesome to track insect populations (particularly staying watchful for non-native and potentially invasive species). But no, the Asian giant hornet (Vespa mandarinia) is not going to destroy America. The one nest and individual that was found around Vancouver last year was destroyed, and this doesn't indicate any establishment. Introduction events happen all the time, all across the world! That region should continue to keep a watchful eye, but for everyone else this is not going to be relevant. There is no invasion, just a small possibility that some may have overwintered in that area.”
Those unsure about insect identification can email an image to Lynn Kimsey at firstname.lastname@example.org or contact the Entomological Society of America at https://www.entsoc.org/ or https://bit.ly/2W2jRmi.
Meanwhile, they're trying to douse the "bloody dumpster fires."
(Update: UC Davis distinguished professor Walter Leal, who studied and worked in Japan, asked a Japanese friend today about the origin of "murder hornet": The Asian giant hornet, Vespa mandarinia, is called “Kiiro Suzume Bachi (キイロスズメバチ)” in Japanese. It injects its venoms, sometimes inducing severe anaphylaxis. The article in BBC introduced Asian giant hornet, Vespa mandarinia as “murder hornet” is at https://www.bbc.com/news/52533
- Author: Royce Larsen
Oaks and Oak Woodlands Explained
“Natural History of the Central Coast Bioregion” (adapted from Gregory Ira's announcement: https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=31003) The publication's lead author, Bill Tietje (Environmental Science, Policy, and Management, University of California, Berkeley), with co-authors William Preston (Geographer Emeritus, Cal Poly, San Luis Obispo) and Anne Polyakov (University of California, Berkeley; currently a Masters Student, University of Washington), created a highly readable and engaging description of the Central Coast Bioregion. “We strived to write in everyday English and create a scientifically accurate and engaging presentation.” The authors succeeded on both counts by use of plain language, common plant and animal names, and short paragraphs supported with over 65 high-quality photographs, four maps, two diagrams, ten vignettes, and 70 references for further reading.
The Central Coast Bioregion, an area between the Pacific Ocean and the San Joaquin Valley, and extending from Monterrey south to Santa Barbara, is home to wildly popular and lesser known destinations. Well known areas include the Big Sur Coast, the estuaries at Elkhorn Slough and Morro Bay, and Monterrey Bay Aquarium. Some of the hidden gems are Pinnacles National Park, Santa Barbara Botanic Garden, and the Gardens of the La Purisima Mission. Together, the authors describe the origins and present composition of the region's environments: “Across the region's 15,000 square miles, physical, and biological processes, combined with time and human actions, have resulted in a broad range of ecosystems, each harboring distinct assemblages of plants and animals.” The publication uses engaging vignettes to highlight local conservationists, regional wildlife, historical and contemporary restoration efforts, and interesting places to explore. It begins with a brief history of the region, providing context to descriptions of subsequent environmental and land-use changes, a reminder to readers that while the future of the central coast is uncertain it will be shaped by our actions. You can find the publication at:https://anrcatalog.ucanr.edu/pdf/8597.pdf
Sharing Oak Woodland Research through a Popular Website (adapted from Devii Rao, Bill Tietje,Luke Macaulay, and Judi Young) Since its creation in 1995, the University of California Oak Woodland Management website has been a valuable educational resource. Based on Google Analytics data from 2011 to 2017, the website receives an average of 45,000 users annually. It is a repository of nearly 30 years of research and outreach data on the ecology, management, and conservation of California's 8 million acres of oak woodlands.
Recent staff retirements and changes in website standards created a need for an update and redesign. To accomplish this, the University of California Cooperative Extension received a Renewable Resources Extension Act Capacity Grant that allowed us to reformat the website for mobile devices; make the website more functional and visually appealing; add some of the latest research; and promote the website to groups who have not historically used it, in particular, the ranching community.
To increase user friendliness, we developed links at the top of the home page for the three primary target audiences: homeowners, land-use planners, and ranchers. On the home page, we also highlighted five topics that receive the most hits: species identification and ecology; oak regeneration and restoration; economic and ecological values of woodland stands; threats to oak woodlands; and woodland wildlife. The new website, now called UC Oaks, went live in June of 2020.
The new flexible website design will allow us to continuously meet the needs of our clientele. With its new look and expanded reach, we hope that the website will be a one-stop-shop for everything people need to know about oak woodland conservation and management. https://oaks.cnr.berkeley.edu/
This Webinar will be tomorrow, March 18, 2020
Tune In and Register below
Dr. Ben Faber will discuss plant growth regulators (PGRs), a powerful tool available for increasing fruit size and yield in an existing avocado orchard. Gibberellic acid (GA3) was registered for use on California avocados in March 2018 to improve fruit productivity. The handling, timing and application rate are critical and the reasons will be included in this discussion. Approval of one hour of DPR continuing education unit is pending.
Avocados in some parts of coastal California have been blooming. Some of them got hit by the cold weather in the first part of February. In the coldest areas there was a little bit of new leaf damage, but this has been minimal.
Some browning of some flowers and stems (pedicels - the little stalks the connect the flowers to the larger raceme/panicle) may have occurred, but I haven't heard of major flower damage.
It's early days for flowering, though, and most ‘Hass' trees are not very far along, but seem like they area about to burst. A recent visit on a 40 acre farm in Saticoy had trees in a whole range of stages, some with no flowers pushing, some with panicles just starting to open individual flowers and many trees on their north sides' completely quiet. Many are still just pushing into the cauliflower stage,
which is the ideal time is for applying Pro-Gibb to improve fruit set in healthy orchards.
Application time is when 50% of the trees in the block have 50% of their bloom in the cauliflower stage. This is a judgment call when there can be such huge variation in bloom across and orchard. It's going to be a best estimate call for when to do the application. As usual with a new technology/practice don't apply to the whole orchard so that you can see whether the application is warranted.
For a more detailed discussion of gibb application, read Carol Lovatt's article: