- Author: Whitney Brim-DeForest
This field day is open to the public. Please share broadly to those who may be interested in attending.
UCANR California Rice Virtual Field Day
When: August 26, 2020, 1:00-3:00 PM
Where: Online Zoom Webinar
Host: Whitney Brim DeForest, UC ANR County Director, Sutter-Yuba Counties and CE Rice and Wild Rice Advisor
Registration: $20.00
Objectives/goals: The UC Cooperative Extension and California Rice Research Station will update attendees in the areas of variety development, disease and arthropod management, weed control, weedy rice, and fertility.
The full agenda can be viewed here.
Who should attend: California rice growers, Pest Control Advisers, and others interested in California rice production systems.
Continuing education units: Applied for 1 CEU from the California Department of Pesticide Regulation (DPR) and applied for 1 CEU from Certified Crop Adviser (CCA)
Featured speakers:
- Russell Rasmussen, Associate Director, California Rice Experiment Station, California Cooperative Rice Research Foundation
- Bruce Linquist, CE Specialist, Dept. of Plant Sciences, UC Davis
- Kassim Al-Khatib, CE Specialist, Dept. of Plant Sciences, UC Davis
- Whitney Brim-DeForest, CE Rice and Wild Rice Advisor & County Director, Sutter-Yuba Counties
- Luis Espino, CE Rice Farming Systems Advisor & County Director, Butte County
- Ian Grettenberger, CE Assistant Specialist, Dept. of Entomology, UC Davis
- Michelle Leinfelder-Miles, CE Farm Advisor, San Joaquin County
Contacts for more information:
- Logistics and registration: Rachel Palmer, ANR Program Support Unit, (530) 750-1361
- Course content:Whitney Brim-DeForest, UC ANR County Director, Sutter-Yuba Counties and CE Rice and Wild Rice Advisor
This field day is open to the public. Please share broadly to those who may be interested in attending.
THIS EVENT WILL BE RECORDED FOR EDUCATIONAL OR PROMOTIONAL USE BY THE UNIVERSITY OF CALIFORNIA. CONTACT THE ORGANIZERS OF THIS EVENT FOR MORE INFORMATION.
- Author: A. Katrina Hunter
- Author: Pamela Kan-Rice
While most Californians are staying home to slow the spread of the novel coronavirus, California farmers, farmworkers and other agricultural professionals are out in the fields and packing houses working to produce food. With increased demand for personal protective equipment, or PPE, to protect against COVID-19, these essential workers are facing shortages. Agricultural commissioners in 28 counties are hearing from farmers who are having trouble getting PPE for their employees and farmers in another 11 counties who are worried about running out of PPE in the next month or two according to a California Department of Pesticide Regulation survey.
Gloves, N95 respirators, coveralls and other gear that workers wear to protect themselves from COVID-19, pesticides, dust and other health hazards are in short supply as priority is given to health care workers during the pandemic.
To reduce the spread of COVID-19, workers may wear homemade face coverings, but for applying pesticides, they must wear respirators specified on the pesticide product label, said Whitney Brim-DeForest, UC Cooperative Extension rice advisor.
Pesticide applicators may use gear that is more protective than required by the product label and regulations.
“Although this could change in the days ahead, half-mask and full-mask respirators are more available than disposable N95 respirators for now,” said Lisa Blecker, coordinator for the UC Pesticide Safety Education Program.
Before the pandemic, 10% of N95 respirators from 3M went to health care, but that number is now 90%, the company said in a letter to distributors. This has led to significant backorders of PPE supplies for distributors.
Carl Atwell, president of Gempler's, an online distributor of worker supplies,, said that before the crisis, normal lead times for PPE was up to 10 days. He estimated disposable respirators will become available in the fall and other PPE supplies in August.
In the meantime, there is alternative PPE that agricultural professionals can use during the shortage.
Atwell suggests looking for lesser-known brands of PPE as opposed to the first tier of choice: “It's sort of like searching for Purell hand sanitizer. Purell brand might be out of stock, but can you find a different disinfectant?”
On Gempler's website, the more recognizable Tyvek coverall from Dupont is sold out, however disposable protective clothing is available from other brands. Reusable chemical-resistant clothing is also available as opposed to their disposable counterparts. Supplies in high demand are reusable and disposable nitrile gloves, protective clothing, disposable respirators and certain protective eyewear, such as goggles and face shields.
For workers who will be applying pesticides, Blecker and Brim-DeForest offered some guidelines on how to meet PPE requirements as the shortage continues.
General PPE requirements: “Remember, the label is the law,” said Brim-DeForest. “PPE requirements for agriculture are not being loosened.” The UCCE advisor recommends purchasing only what you need for the season and choosing reusable PPE whenever possible. Growers who have excess supplies of PPE can coordinate with their county agricultural commissioner or UCCE advisor to help other producers in their area.
Respirators: If you can't find the respirator required on the label, Blecker said, “Use an alternative, more-protective respirator. For example, if an N95 is required, you can use a half-mask with N95 particulate filters; these can be stand-alone filters or ones that attach to an organic vapor cartridge. You could also use a different pesticide that doesn't require a respirator. Consult with your PCA (pest control adviser) for options.”
Gloves: Chemical-resistant gloves, usually 14 mil or more in thickness are required for most California pesticide applications and should be worn by mixers, handlers and applicators. If nitrile gloves are not available, viton and laminate gloves are universal chemical-resistant materials for most pesticide labels. If the glove material is specified on the label, that instruction must be followed.
“Disposable gloves less than 14 mil can be worn, but not for more than 15 minutes at a time,” Blecker said. “Farmers should also note that thinner gloves cannot be layered on top of one another.”
Coveralls: Coveralls should be worn when required by the pesticide label or when the signal word is “WARNING” or “DANGER,” or when applying by backpack or airblast. “Coveralls can be made out of high-density polyethylene fibers (Tyvek and other brands), which are disposable, or cotton, which are reusable,” Brim-DeForest said. “If reusable coveralls are worn, the employer must ensure employees are provided clean coveralls.”
Goggles/faceshields: Faceshields are required for mixing and loading pesticides only if it's stated on the label. “If a faceshield is unavailable, a full-face respirator can be used,” Blecker said. “Goggles or protective eyewear should always be worn in California when handling pesticides, regardless of what the label says. The faceshield, goggles or safety glasses must provide front, side and brow protection and meet the American National Standards Institute Z87.1 standard for impact resistance.
For more information about PPE, contact your county agricultural commissioner or see the California Department of Pesticide Regulation's posters at https://www.cdpr.ca.gov/docs/whs/pdf/gloves_for_pesticide_handling.pdf and
https://www.cdpr.ca.gov/docs/whs/pdf/n95_alternatives_for_pesticide_handling.pdf.
UC IPM also covers these topics in their pesticide safety webinar series at http://ipm.ucanr.edu/IPMPROJECT/workshops.html.
UC Agriculture and Natural Resources brings the power of UC research in agriculture, natural resources, nutrition and youth development to local communities to improve the lives of all Californians. Learn more at ucanr.edu.
MEDIA CONTACTS:
Lisa Blecker, coordinator for the UC Pesticide Safety Education Program and Office of Pesticide Information and Coordination, lblecker@ucanr.edu
Whitney Brim-DeForest, UC Cooperative Extension rice advisor in Sutter and Yuba counties, wbrimdeforest@ucanr.edu
Katrina Hunter, UC Integrated Pest Management Program pesticide safety writer, akhunter@ucanr.edu
- Author: Luis Espino
As you know, we have been monitoring armyworm flights with pheromone traps across the valley since 2018. This year, the first set of traps were put out on 4/10 near Princeton, and today we put out a few more. We checked the first traps today, and we got an average of 2 moths per night per trap. That is high for this time of year; in 2018 and 2019 we were not catching any moths until the first week of May. We will start updating our website, UC Rice Online, once a few more traps are established. Remember you can subscribe to receive email alerts every time the numbers are updated on the website.
- Author: Ian Grettenberger
- Author: Luis Espino
Want to help make sure your freshly planted rice fields don't look like the muddied mess on the left below (vs. clear on right) following a pyrethroid application? Wondering if your tadpole shrimp are becoming less susceptible to pyrethroids? We do too! Pyrethroids are widely used for managing resistance and resistance seems to be a growing issue.
We are looking for additional fields where we can sample tadpole shrimp to test for pyrethroid resistance. We will be gathering soil/shrimp and then using these samples to run laboratory bioassays and measure susceptibility. The goal is to start measuring precisely how susceptible populations are in different fields. This will help us determine precisely how resistant known resistant populations are, how prevalent low levels of resistance are, and how “susceptible” currently susceptible populations are to generate baseline data. This will help generate the long-term baseline data we need to stay on top of this issue. We will anonymize any publicly available data. In addition, we hope that by measuring resistance in individual fields, we can help you by noting any susceptibility slippage that may not have shown up yet in terms of control. We can also help address questions about whether lack of control is due to resistance or application issues.
Types of fields:
- Fields with known resistance to pyrethroids in tadpole shrimp (control issues).
- Suspect fields where you think resistance is an issue, but it is a just a hunch or a concern.
- Any other field. Even if pyrethroids have been working well, it is still good to know susceptibility levels and for us to generate baseline data.
What we need:
- Access to field(s)
- Summary of your ability to manage tadpole shrimp with pyrethroids, any declines in susceptibility, etc.
If you are interested please email or call (Ian) at imgrettenberger@ucdavis.edu or 530-752-0473.
- Author: Luis Espino
The last time we saw a severe blast epidemic was 2011. Since then, we haven't had much blast; in fact, I had not see any blast at all during several years. I don't think 2019 qualifies as a severe blast year, but there is more blast than in the previous few years.
Blast is caused by a fungal pathogen, Pyricularia oryzae. This fungus can affect any plant part, and usually we refer to blast according to the tissue affected. Leaf blast, node blast, collar blast, and neck blast (when it affects the node right below the panicle) are all caused by the same pathogen.
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Typical and larger leaf blast lessions, collar and node lessions.
Neck blast
Blast can surive in crop residue, move with seed, and move between fields by producing airborne spores called conidia. In California, we typically see leaf blast starting at mid tillering. Blast infection at this time causes leaf lesions that in severe cases can burn plants to the water level. However, most of the time these severe symptoms are limited to small areas of the field. During heading, neck blast can cause empty heads when infections occur soon after the panicle emerges from the boot.
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Left, leaf blast that has burned plants to water level in circular pattern. Right, larger area of field affected with leaf blast.
Several factors favor blast development. Moderate warm daytime temperatures, cooler nights, and long periods of leaf moisture are good for blast development. High nitrogen rates tend to aggravate blast, and typically one can see blasted circles where plants have been killed to the water level in areas of aqua overlap. Draining fields during the season increases the risk of blast infection.
Of the rice varieties grown in California, M-205 and M-104 were considered more susceptible than M-206. Variety M-205 has been replaced by M-209, which was released in 2015. Since there hasn't been much blast pressure in the past few years, it was not known how M-209 was going to react to blast. This year seems to indicate that M-209 might be more susceptible to blast than M-206. I still have not heard much about M-105, the M-104 replacement released in 2011. Variety M-210, released in 2018, is resistant to the blast races present in California.
If leaf blast is very severe, a fungicide application may be appropriate. However, this level of disease is uncommon under our conditions. Leaf blast does indicate the need to protect the panicles during heading with a fungicide application at about 50% heading.
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