- Author: Houston Wilson
- Author: Jhalendra Rijal
- Author: David Haviland
Crop sanitation will be key to controlling the invasive carpophilus beetle
Growers and pest control advisers (PCAs) should be on the lookout for a new pest called carpophilus beetle (Carpophilus truncatus). This pest was recently found infesting almonds and pistachios in the San Joaquin Valley, and is recognized as one of the top two pests of almond production in Australia. Damage occurs when adults and larvae feed directly on the kernel, causing reductions in both yield and quality.
Populations of carpophilus beetle were first detected in September in almond and pistachio orchards by University of California Cooperative Extension Specialist Houston Wilson of UC Riverside's Department of Entomology. Pest identification was subsequently confirmed by the California Department of Food and Agriculture.
Wilson is now working with Jhalendra Rijal, UC integrated pest management advisor, North San Joaquin Valley; David Haviland, UCCE farm advisor, Kern County; and other UCCE farm advisors to conduct a broader survey of orchards throughout the San Joaquin Valley to determine the extent of the outbreak.
To date, almond or pistachio orchards infested by carpophilus beetle have been confirmed in Stanislaus, Merced, Madera and Kings counties, suggesting that the establishment of this new pest is already widespread. In fact, some specimens from Merced County were from collections that were made in 2022, suggesting that the pest has been present in the San Joaquin Valley for at least a year already.
“It has likely been here for a few years based on the damage we've seen," Rijal said.
This invasive beetle overwinters in remnant nuts (i.e. mummy nuts) that are left in the tree or on the ground following the previous year's harvest. Adults move onto new crop nuts around hull-split, where they deposit their eggs directly onto the nut. The larvae that emerge feed on the developing kernels, leaving the almond kernel packed with a fine powdery mix of nutmeat and frass that is sometimes accompanied by an oval-shaped tunnel.
Carpophilus beetle has been well-established in Australia for over 10 years, where it is considered a key pest of almonds. More recently, the beetle was reported from walnuts in Argentina and Italy as well. Carpophilus truncatus is a close relative to other beetles in the genus Carpophilus, such as the driedfruit beetle (C. hemipterus) that is known primarily as a postharvest pest of figs and raisins in California.
Monitoring for carpophilus beetle is currently limited to direct inspection of hull split nuts for the presence of feeding holes and/or larvae or adult beetles. A new pheromone lure that is being developed in Australia may soon provide a better monitoring tool for growers, PCAs and researchers.
“We're lucky to have colleagues abroad that have already been hammering away at this pest for almost a decade,” said Haviland. “Hopefully we can learn from their experiences and quickly get this new beetle under control.”
The ability to use insecticides to control carpophilus beetle remains unclear. The majority of the beetle's life cycle is spent protected inside the nut, with relatively short windows of opportunity available to attack the adults while they are exposed. The location of the beetles within the nut throughout most of their life cycle also allows them to avoid meaningful levels of biological control.
In the absence of clear chemical or biological control strategies, the most important tool for managing this beetle is crop sanitation.
“Given that this pest overwinters on remnant nuts, similar to navel orangeworm, crop sanitation will be fundamental to controlling it,” Wilson said. “If you needed another reason to clean up and destroy mummy nuts – this is it.”
In Australia, sanitation is currently the primary method for managing this pest. And here in California, new research and extension activities focused on carpophilus beetle are currently in the works.
“It's important that we get on top of this immediately,” said Wilson. “We're already starting to put together a game plan for research and extension in 2024 and beyond.”
If you suspect that you have this beetle in your orchard, please contact your local UC Cooperative Extension farm advisor (https://ucanr.edu/About/Locations/), County Agricultural Commissioner (https://cacasa.org/county/) and/or the CDFA Pest Hotline (https://www.cdfa.ca.gov/plant/reportapest/) at 1-800-491-1899.
/h3>- Author: Jeffrey P. Mitchell
Soil health monitoring conducted at SJV reduced disturbance and cover cropped fields!
As part of the USDA NRCS Conservation Innovation Grant, Creating a no-till network in California, extensive baseline soil sampling has now been done at several San Joaquin Valley farms that are employing the soil health management practices of no-tillage, strip-tillage and/or cover crops. These farms include sites at the diversified permanent and annual crop farm of Eddie Sajian in Hanford, CA, the dairy silage fields of Rick Adams near Laton, CA, the grazing pasture lands of Paul Strojan in Farmington, CA, cotton fields at Bowles Farming in Los Banos, CA, and tomato acreage of Woolf Farming in Huron. Determinations of soil carbon, aggregation, infiltration, and % residue cover have been done at each site and findings have been discussed with partner farmers for each location. In addition, participating farmers have been encouraged to begin conducting their own ongoing monitoring by using the assay techniques shown here. They were also provided with a PVC meter square quadrat to use in sampling surface biomass and a set of sieves as shown below that are used for determinations of soil aggregate stability.
- Author: Mike Hsu
The Fresno-Merced Future of Food Innovation Initiative (F3) – of which UC ANR is an anchor institution – took a big step forward during the UC Regents meeting May 18.
The Regents unanimously approved the formation of F3 Innovate – a new 501(c)(3) nonprofit that will raise funds for the partnership initiative that also includes the Central Valley Community Foundation (CVCF), California Department of Food and Agriculture, UC Merced and CSU Fresno.
Largely funded by a $65 million Build Back Better grant from the U.S. Economic Development Administration, F3 aims to advance innovation and entrepreneurship in agrifood technology, strengthen food systems, bolster local and regional economies, and bring greater prosperity to the San Joaquin Valley and beyond.
The new F3 Innovate nonprofit will focus on agrifood systems research and commercialization, services for micro-enterprises and small businesses in under-resourced communities, ag-tech innovation seed funding, and building a talent pipeline to sustain these efforts.
“This 501(c)(3) is critical to all of that, because it really lets us bring together the public and private partners, and ensures that broader stakeholder participation and benefit,” said Glenda Humiston, UC vice president for agriculture and natural resources, during her presentation to the Regents (view recording of the meeting).
UC Merced Chancellor Juan Sánchez Muñoz and CVCF President and CEO Ashley Swearengin also spoke passionately during the meeting about the need to form the nonprofit as a key connector and catalyst for the F3 initiative.
F3 – and the new F3 Innovate – will continue to take shape through the work of Gabe Youtsey, UC ANR chief innovation officer; Josh Viers, associate dean for research of UC Merced's School of Engineering; and many other academics and staff across UC ANR and UC.
"Establishing F3 Innovate as a 501(c)(3) nonprofit organization is a strategic move designed to unlock and accelerate agriculture technology from lab to market. It will pave the way for a wider range of collaboration opportunities between the UC and industry, and ensure the inclusion and representation of all our stakeholders, from small and socially disadvantaged farmers to startups and corporates," said Youtsey, who is also founder of The VINE, UC ANR's Innovation & Entrepreneurship program that is co-leading F3.
"The UC Regents were enthusiastic about this partnership as it aligns perfectly with our mission of transforming cutting-edge agricultural research into practical, market-ready solutions while doing the hard work of engaging our local workers, communities and farmers to adopt these new technologies," Youtsey added. "It enables us to foster deep and meaningful collaborative relationships with industry partners, advancing technology commercialization that is inclusive and truly beneficial to all involved."
- Author: Sandipa Gautam
Monitoring California red scale populations by using pheromone traps and degree days
California red scale is an armored scale that attacks all citrus varieties. It attacks all aerial parts of the tree including leaves, fruits, twigs, and branches by sucking on plant tissue with its long filamentous stylet. Heavy infestations cause leaf yellowing and drop, dieback of twigs, and occasional death of the infested tree. Heavily infested fruits with patches of California red scale may be downgraded in the packinghouse. Growers use monitoring methods, i.e., pheromone trapping, examining fruit, and bin counts (at harvest) for making treatment decisions.
In the San Joaquin Valley, many citrus growers rely on the use of pheromone traps to monitor male-scale flights. Following the biofix (first male flight) degree day units (DD) are used to predict when the next crawler emergence or next-generation flights is occurring. Degree days are heat units accumulated above the lower developmental threshold of an insect and have been long used to monitor the seasonal activity of California red scale populations. Knowing when the most vulnerable life stage of the insect is present helps growers make timed insecticide applications.
Citrus IPM research group led by Dr. Sandipa Gautam at Lindcove Research and Extension Center updates degree day accumulation in the San Joaquin Valley counties. Information for different counties can be found here.
Pheromone traps are used to monitor either weekly changes in male flights or to track densities during flights, especially the fourth flight.
The squares represent 20% of the card – you count what is inside the squares on both sides and multiply by 5 to estimate the total number.
How to use pheromone traps for weekly monitoring male flights?
- Monitor 5 to 6 orchards that have a known population of California red scales every week,so thatyou can determine when flights are occurring and time sprays.
- Change the sticky cards weekly and the pheromone lure caps monthly through October.
- Use two to four pheromone traps per10-acre block;add two traps for each additional10 acres.
How to use trap card information to make management decisions?
- Hang pheromone traps with a fresh lure in early March to detect the biofix (first male flight). Historically, biofix for Kern County occurs around the 1st of March, and biofix for Tulare, Fresno, and Madera Counties occurs around March 15.
- Use the biofix and degree-days to predict when crawler emergence or next flight is occurring. Degree days are accumulated heat units over the lower developmental threshold of California red scale.
- Crawler emergence for first-generation will occur 550 degrees days after biofix.
- Subsequent flights will occur at intervals of 1,100-degree days after the biofix of the first male flight (1,100 DD for 2nd flight; 2,200 DD for 3rd flight; 3,300 DD for 4th flight and 4,400 DD for 5th flight). Subsequent crawler emergence for the 1st, 2nd, and 3rd generation occurs at 550 DD, 1650 DD, and 2750 DD after the biofix.
- Check the Lindcove Research and Extension Center Website for updated information on accumulated degree day
How to use pheromone traps to determine areas of heavy infestation?
- Use 2 to 4 pheromone traps per10-acre block;add 2 traps for each additional10 acres.
- Time placement of traps at the beginning of the biofix for the flight and remove them at the end of each flight and count scales and record the numbers.
In the past, when an average of more than 1,000 scales are trapped during the 4th flight and fruit is infested with scale at harvest, a pesticide application is planned for the next season. However, this threshold of 1,000 scales per flight developed in the 1980s is no longer a stand-alone tool for determining when treatments are necessary. It is critical to use other tactics, such as fruit and twig examination.
Note that pheromone cards are not reliable predictors of scale populations on their own. In all orchards in all growing regions,whether Aphytis wasps are released or not, conduct visual inspections of citrus fruit once a month during August, September, and October to confirm that fruit is free of scale.
Situation 1: Scale densities on traps may be high, but the fruit is free of scale:
- When Movento or Admire (and generics) are used because they remove scale from leaves and fruit but not the wood of the tree.
- Aphytis prefer to attack virgin female scales and the males may escape parasitization, resulting in a high number of male scales on traps.
Situation 2: Very few male scales on traps, but the scale is found on fruit
- When insect growth regulators (buprofezin and pyriproxyfen) are used, the frequently molting male scales are more affected than female scales.
- When mating disruption is used, males cannot find the trap cards so their densities on traps can be very low. A threshold of 50 scales per flight is helpful in determining if mating disruption is effective.
Consult UCIPM guidelines for management options.
- Author: Anthony Presto
Residential wood burning is the largest single source of particulate matter pollution in the Valley during winter months. For this reason, the District's residential wood smoke reduction program imposes restrictions on the use of fireplaces, wood stoves, fire pits and chimneys. The District recommends using other methods to heat your home unless wood burning is your sole source of heat. For full details on the District's Residential Wood Smoke Reduction Program, visit www.valleyair.org/rule4901.
Another source of air pollution are small engines on gas-powered yard care equipment, which have no emission controls. One gas-powered lawn mower can pollute as much as 12 late-model cars.
For every gas-powered lawn or garden tool, there is an electric or manual alternative that works just as well.
The District's Clean Green Yard Machines yard care incentive program provides significant rebates on electric lawn mowers, trimmers, edgers, pole saws and chain saws. For details on these incentives visit www.valleyair.org/cgym.
In addition, the Valley Air District suggests using a rake or broom instead of a blower. Leaf blowers create particulate matter in the form of dust and can be a nuisance to your neighbors.
Anthony Presto is the Outreach & Communications Representative for the San Joaquin Valley Air Pollution Control District