David W. Cudney, UC Cooperative Extension specialist emeritus, passed away in Riverside on March 30. He was 82.
Cudney joined UCCE in 1964 as a farm advisor for Imperial County. In 1978, he became a UCCE weed science specialist for Southern California, based at UC Riverside. While working as a specialist, he earned his Ph.D. from UC Riverside in 1989.
In 1992, Cudney and six Extension specialist colleagues from all over the western United States, published Weeds of the West, a guide book to identifying weeds in Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming. The 11th edition, containing more than 900 color photographs showing the early growth stages, mature plants and features for positive identification of each weed, was published in 2012.
Cudney, who was active in professional organizations, served as president of the California Weed Society in 1995. He retired in 2003.
“I met Dave as a grad student at UC Davis when I started my program working on a basic study of herbicide resistance,” said Jodie Holt, director of the UC Riverside Botanic Gardens and professor emerita. “Dave’s the one who cajoled me into presenting a poster at a Weed Day and becoming active in the weed science community. Throughout my career he was a great mentor who kept me and my students connected to on-the-ground weed science.”
Jodie Holt, left, and Dave Cudney inspect perennial ryegrass for bermudagrass invasion in the 1990s.
Holt also remembered Cudney’s kindness as a friend.
“On a personal note, when our son was interested in flight simulation software, for his 14th birthday, Dave surprised him by taking us all on a flight and letting Doug fly the plane,” she said. “He was a wonderfully positive, kind and generous friend and colleague!”
Cudney is survived by his wife, Loretta Cudney, and his children Michael Cudney of Riverside; Jana Cudney of Ontario; and Lisa Zaldivar and her husband, Anthony Zaldivar, and their children Alyssa and Christopher, all of San Dimas and Anthony Zaldivar of Palm Desert; his sister, Rita Suminski and her husband, Russell Suminski of Minden, Nevada. — By Pam Kan-Rice, UCANR
USDA Foreign Ag Service — We see them every time we purchase fresh fruits and vegetables: price look up (PLU) labels. The little coin-size stickers are stuck to everything from apples, bananas, and cantaloupes to watermelons, yams, and zucchini.
According to the Sustainable Packaging Coalition , PLU labels have been used globally for more than 30 years with the International Federation for Produce Standards issuing more than 1,400 PLU codes.
PLU labels offer many benefits to the agriculture, trade, and retail industries. The labels lower costs and optimize handling by digitizing supply chain management, minimizing packaging, and reducing time at the point of purchase – something we can all appreciate when rushing through the self-checkout lane. When it comes to agricultural trade, PLU codes also help exporters and importers consistently and quickly identify and track products across the globe. Whether you purchase a Red Delicious apple in the United States, Mexico, or Vietnam, the PLU code is the same.
USDA Research Chemist Dr. Gabriel Patterson pours one of the experimental home compostable adhesives to sticker backing during the research process. The team tested more than 100 formulas to determine the top three adhesive (photo by James McManus).
Unfortunately, PLU labels have also created a sticky situation for composters, the environment, and even U.S. exporters. Why? PLU labels are not biodegradable, which means they contaminate produce that’s tossed in the compost pile or sent to commercial composting facilities. As a result, the produce generally ends up in landfills, which creates more food waste, increases methane emissions, and negatively affects climate change.
Several countries, led by France and New Zealand, have enacted legislation that will require PLU labels to be certified home compostable. This has posed a challenge for U.S. exporters by creating a trade barrier that puts millions of dollars of U.S. fresh fruit and vegetable exports at risk. The U.S. Department of Agriculture (USDA) has stepped in to help solve the problem in an effort to help reduce trade barriers and mitigate climate change.
With research and development funds provided by USDA’s Foreign Agricultural Service’s (FAS) Technical Assistance for Specialty Crops Program, FAS and USDA’s Agricultural Research Service are working to produce compostable PLU labels. FAS and ARS are collaborating with the International Fresh Produce Association (IFPA) and Sinclair Systems International to meet the EU standards. The goal is to develop adhesives that are both food-safe and compostable. When achieved, this will allow American companies to export fruits and vegetables as usual while helping to decrease food waste and methane emissions.
Scientists at the USDA Western Regional Research Center in Albany, CA apply test and control PLU labels to grapefruits and sweet potatoes to evaluate their effectiveness (photo by James McManus).
To date, the research team has tested more than 100 formulas to determine the top three adhesives that produce the desired biodegradation process. The team is performing final tests to confirm that these bio-based adhesives pass the home-compostable degradation test. They will then tackle scale-up adhesive coating trials as a key milestone toward commercialization.
USDA has also coordinated closely with the IFPA on outreach and education to U.S. produce exporters to demonstrate the benefits of greener, environmentally friendly PLU labels and adhesives. Once implemented, the new PLU labels and adhesives will solve a sticky problem for U.S. exporters and ultimately help reduce methane emissions, another step towards more sustainable agricultural production and trade.
In the United States, blueberries are the second-most produced berry, and their popularity has grown exponentially in less than 30 years – up from 45,000 tons grown in the 1990s to 339,000 tons in 2019. ARS researchers are working hard to help farmers keep up with consumer demand.
“In blueberry, we focus on improving the shelf life of fruit so that it reaches consumers with consistently better texture and flavor,” said Claire Luby, plant geneticist with HCPGIR. “This also means developing new types of blueberries that are easier to harvest using mechanical harvesting equipment.”
Blueberries are notorious for being difficult to harvest with machinery because they bruise so easily.
Perhaps a larger challenge for Luby and her colleagues is developing a cultivar that is resistant to a disease known to be a scourge of the berry: blueberry shock virus.
“We’re studying diverse blueberry plants to understand the genetic basis for blueberry shock virus, which can significantly impact yields for farmers,” she said. “Our hope is to use the insights from this project to develop new cultivars that are resistant, or at least more tolerant to, the disease.”
Blueberry shock virus has caused annual crop losses of 34-90% in the Pacific Northwest.
“The fruits that we focus on in this project are some of the most consumed fruits in the United States and contribute important nutritional benefits to consumers,” Luby said. The fruits are also economically important to the region, with Washington and Oregon being the nation’s top two producers.
According to Luby, researchers combine traditional plant breeding with genomics to find the right genetic mix for their disease-resistant cultivars.
Their plant breeding programs use traditional techniques of taking pollen from one plant and using it to pollinate a different plant with complementary characteristics. They then determine if the progeny of these crosses have the new characteristics that meet the goals of the breeding programs. In general, these techniques have been used in one form or another by people trying to improve agricultural crops for millennia.
“Where the genomics piece comes in is to try to improve the accuracy and speed of the plant breeding process,” Luby explained. “We are now able to obtain a lot more genetic information about the plants and we can use that information to potentially predict whether an offspring of a given cross might have the characteristics we are looking for before we plant it out in the field. This is important because it can increase the speed of the plant breeding process.”
Traditional blueberry breeding can take more than 20 years from the time an initial cross is made to when a consumer might eat from a resulting cultivar.
“Our goals are to develop blueberries that require fewer chemical inputs to fight disease, which can be better for both the environment and for growers’ bottom lines,” Luby said. – By Scott Elliott, USDA-ARS Office of Communications
Ocean Mist Farms, the leading year round producer of fresh California artichokes, is expecting an outstanding 2023 spring crop of artichokes from their northern California growing region in Castroville.
“The storms that devastated parts of California during the winter months put the season behind about 4 weeks,” said Ben Wilson, Ocean Mist Farms artichoke commodity manager. “That being said, we have recovered nicely, and are seeing outstanding quality artichokes focused primarily on large sizes – jumbos/12-count.”
“We are excited to see the way our spring crop has lined up this year across our entire family of artichoke offerings,” continued Wilson. “We are expecting excellent quality and plentiful volumes of both our conventional and organic green artichokes, as well as our proprietary and sought-after purple artichoke variety.”
Ocean Mist Farms Sr. Director of Marketing, Mark Munger
Sr. Director of Marketing, Mark Munger noted, “Our spring crop peak is an excellent opportunity for our customers. Our research shows that when retailers create displays with a variety of packs, products, and colors, it generates excitement with consumers resulting in increased sales.”
This abundant volume ensures retailers will have:
Promotable volumes through the end of May
Great promotional opportunities with multiple artichoke products
Availability on various packs and sizes
Ocean Mist Farms is currently running the “Gold Standard” promotion, which is a national consumer sweepstakes aimed to get consumers primed and excited about the spring artichoke season.
To learn more about Ocean Mist Farms, visit www.oceanmist.com. To receive weekly trade information, please sign up HERE.
About Ocean Mist Farms
Ocean Mist Farms, a fourth-generation family-owned business in Castroville, CA, the largest grower of fresh artichokes in North America, is committed to delivering the highest standards in the industry for food safety, product quality, customer service, innovation, and sustainability. The company’s full line of 30+ fresh vegetables include their award-winning green and purple artichokes, as well as their Season & Steam value-added line of products. To stay up to date on the 2023 artichoke season, follow Ocean Mist on Instagram. To learn more about Ocean Mist Farms, visit www.oceanmist.com. For great recipe inspiration and preparation tips, consumers can follow the brand on Pinterest, Facebook,Instagram,LinkedIn and Twitter.
Announced by the California Department of Food and Agriculture’s (CDFA) Citrus Pest and Disease Prevention Division (CPDPD), the CDFA’s Asian citrus psyllid (ACP) quarantine program now requires all harvesters/farm labor contractors (FLCs) – referring to any person/establishment who employs people to perform work related to grove management and/or harvesting commercial citrus fruit – to have a valid compliance agreement to harvest citrus groves.
FLCs will have until June 15, 2023 to obtain and sign a compliance agreement. Any FLCs operating in citrus groves without a compliance agreement by the June 15th deadline will be in violation of quarantine requirements.
Compliance agreements can be provided to you by directly reaching out to your local CDFA ACP/HLB Program contact. Completed compliance agreements can be returned to CDFA via local regulatory staff or by email to ACPCompliance@cdfa.ca.gov. Contact details by region can be found below:
The 2022-23 Valencia orange forecast is 16.2 million cartons. This forecast was based on the results of the 2022-23 Valencia Orange Objective Measurement (O.M.) Survey, which was conducted from January 9 to February 28, 2023. Estimated fruit set per tree, fruit diameter, trees per acre, bearing acreage, and oranges per carton were used in the statistical models estimating production.
The season experienced scattered precipitation in some areas which caused a rainy start to the growing season. Survey data indicated an average fruit set per tree of 616, a 13.9% increase from the previous year and 12.2% above the five-year average of 549. The average March 1 diameter was 2.391 inches, down 2.8% from the previous year and 5.1% below the five-year average of 2.520.
SURVEY HISTORY
A Valencia Orange Objective Measurement Survey was conducted from the 1985-86 to 1993-94 seasons before suspension due to a lack of funding. The survey has been conducted since it was reinstated for the 1999-00 season, with the exception of the 2006-07 season due to a substantial freeze. The data from the first three years after the survey was reinstated were used for research purposes in developing crop- estimating models.
SURVEY SAMPLE
A sample of 375 Valencia orange groves were randomly selected proportional to acreage, county, year planted, and variety representation in the state, with 340 of these groves being utilized in this survey. Once a grove was randomly chosen and grower permission was granted, two trees were randomly selected for each grove. For each randomly selected tree, its trunk was measured along with all connected branches. A random number table was then used to select a branch, and then all connected branches from the randomly-selected branch were measured.
This process was repeated until a branch was reached with no significant limbs beyond it. This randomly-selected branch, called the terminal branch, was then closely inspected to count all fruit connected to it, as well as all of the fruit along the path from the trunk to the terminal branch. Since each selected path has a probability of selection associated with it, a probability- based method was then applied to estimate a fruit count for the entire tree.
In the last week of the survey period, fruit diameter measurements were collected on the right quadrant of four trees surrounding the two sampled trees of every third sampled grove. These measurements were used to estimate an average fruit diameter per tree. The sampled groves were primarily in the top Valencia orange producing counties of Tulare, Kern, Fresno, Ventura, and San Diego.
Growers are now spending an average of $500,000 a year on automation in response to the persistent ag labor shortage, according to the Specialty Crop Automation Report released today and commissioned by Western Growers.
This is the second year the Specialty Crop Automation Report has been released by WG in collaboration with consultants at Roland Berger. The report, which tracks and measures industry progress in harvest automation across the fresh produce industry, is part of WG’s Global Harvest Automation Initiative, which aims to accelerate ag automation by 50 percent in 10 years.
“This year’s report takes a deep dive into some new areas: The European market, Controlled Environment Agriculture, and the innovator’s side of automation,” said Walt Duflock, VP of Innovation at WG. “We found progress from a fundraising and traction perspective in key areas like weeding, spraying and harvest assist – and less progress in other key areas, notably harvest.”
Among the report’s findings:
Around 70 percent of participating growers indicated that they had invested in automation in 2022, with an average annual spend of $450,000-$500,000 per grower. This shows a considerable increase since last year when average investments in automation were around $350,000 to $400,000 per grower per year.
Most progress was made in the weeding and harvest assist segments; market-ready solutions are able to meet grower economic targets and alleviate key challenges, such as lack of labor availability. Growers reported ROIs for weeding solutions of less than one to two years depending on the type of crop and technology used.
Growers want more trained agtech personnel, with 50 percent indicating that they had internal employees who dedicated the majority of their time to the integration of automation investments. This suggests that the process of elevating and upskilling the agriculture workforce is well underway.
The time it takes to build automation solutions is getting shorter and the costs are getting smaller thanks to overall advances in robotics and nonagriculture fields that benefit agtech startups, as well as the increasing talent pool that agtech startups are able to add to their teams.The Specialty Crop Automation Report is available for download by clicking here.
About Western Growers:
Founded in 1926, Western Growers represents local and regional family farmers growing fresh produce in California, Arizona, Colorado and New Mexico. Western Growers’ members and their workers provide over half the nation’s fresh fruits, vegetables and tree nuts, including half of America’s fresh organic produce. Connect and learn more about Western Growers on Twitter and Facebook.
Nearly 500 people with a professional stake in the safety of fresh fruits and vegetables consumed worldwide will gather at Sherwood Hall in Salinas on May 3-4 for the 18th Annual Western Food Safety Conference.
The conference will be held at Sherwood Hall at 940 N. Main St., in Salinas, and will focus on the theme, “Food Safety: The State of the Industry” through speakers, intensive dialogue and education concerning how to keep consumers safe and maintain their confidence.
The conference will provide participants with current produce safety information, research, and regulatory developments in the fresh produce industry that they can apply to today’s environment. The event features industry-leading scientists, executives, and professionals for the latest science-based industry information and networking opportunities. Speakers and panelists include experts in water quality, data science, sustainable agriculture and state and federal regulation.
The May 3 keynote speaker will be William (Bill) Marler, attorney and national expert in food safety with Marler Clark, The Food Safety Law Firm. The May 4 keynote speaker will be Karen Ross, secretary of the California Department of Food and Agriculture.
Topics for the 2023 conference include:
FDA Field Sampling
Rethinking Recalls and Communication in the Supply Chain
Registration fees and sponsors’ support in 2022 helped raise $15,000 for scholarships for Hartnell College agricultural students, adding to more than $100,000 previously shared as a result of the conference.
The Western Food Safety Conference is committed to the inclusion of people with disabilities participating in the event. Online activities are designed to be accessible, meeting the Rehabilitation Act (Section 508). If a person with a disability is requesting reasonable accommodations due to a disability to participate in the event, requests need to be sent to Hartnell College Foundation, (831) 755-6702. Requests for disability accommodations received three business days in advance of the event will be given priority, although an attempt to fulfill all requests will occur.
Celebrating the theme “Thistle be Fun,” the 63rd annual Artichoke Festival takes place June 10-11 at the Monterey County Fair & Event Center, with online ticket sales now available.
The 2023 festival will feature a wide-ranging variety of entertainment, including the popular Chef’s Demo, a farmers market, live music, wine tasting, NEW this year a Saturday Night comedy show, and a quilting challenge.
Following is this year’s lineup, with information about tickets: who wish to sign up should contact joaquin@harmony-at-home.org.
Comedy show
A new event this year is a Saturday night-only standup program called “Thistle Be Funny Comedy Show.” It features comics K-Von at 6:30 p.m., and Jose Sarduy at 8 p.m. The festival offers a special Comedy Combo discount package (two festival tickets, two comedy show tickets, two Saturday wine tasting passes) for $170 plus processing fee. A standalone comedy ticket is $40 for adults only, must be 18 and over.
Doors open to all comedy show guests at 6 p.m., with the entry for festival attendees at the Monterey Room east entrance. Entry for non-festival guests is at the Monterey Room street entrance, on Fairground Road. Remember, children are not allowed inside the Monterey Room for this event. Participants must show a valid ID to enter.
K-Von could be the most famous half-Persian comedian in the world. Millions have seen his appearances on Netflix, NBC’s ‘Last Comic Standing’, and his popular TED Talk that introduced him to a global fanbase. He is the author of the book “Once You Go Persian,” a funny detailing of his upbringing and how he got into comedy.
Jose Sarduy takes audiences on the rollercoaster ride that’s been his life. Born in Cuba and deported because of his father’s political prisoner status, he came to the U.S. at a young age. Growing up with a hard working, and always quirky Cuban family brought loads of funny moments. A graduate of the U.S. Air Force Academy and former officer in the Air Force, Sarduy is also an accomplished aviator and war veterans.
Chef’s Demo
Currently five chefs have confirmed participation for the Chef’s Demo in the Seaside Room, including Chef Brandon Miller of Paella LLC, who will open the demos at 12:30 p.m. on Saturday and Sunday, June 10-11. He will offer recipe inspiration, tips and tricks for cooking artichokes, as well as samples and small bites to enjoy.
In addition, Kevin Fisher from Sea Root at Hyatt Regency Monterey Hotel & Spa will return to the stage at 1:30 p.m. Sunday, June 11. Chefs Ivan Guadarrama from Tarpy’s and Chef Luis Osorio from Rio Grill will also be back for a second year performing demos at 1:30 and 3 p.m., on Saturday, respectively. More chefs are expected to be announced by festival organizers.
Live on the Main Stage
Free with festival general admission, the festival’s lineup of live music Saturday June 10th features the John Michael Band at noon, followed by Wild at Heart at 2 p.m. and Mustache Harbor hardcore soft rock band at 4:30. Sunday June 11th The Chicano All-Stars will start at 12:30, with Shane Dwight appearing at 3 p.m. Also on the Main Stage will be volunteer awards at 11:30 a.m. Saturday, an artichoke-eating contest at 3:30 p.m. Saturday and 2 p.m. Sunday, and a canasta contest at 4 p.m. Saturday and 2:30 p.m. Sunday.
John Michael Band formed in 2010, and features the following: guitarists Dylan Rose, Markus Yamamoto, D.B Walker, Patrick Golden, Vinny Johnson and 17-year-old Becca Kachman; drummers John Brearton, Keith Wieland, Keith Graves (played with Starship, The Tubes and Quicksilver Messenger Service), Tim Burke, Ric Williams, Craig Underwood; bassists Tiran Porter (Doobie Brothers) David De Silva, Ryan Price, Avey Gonzalez, Chuck Pagano. An upbeat and versatile band playing rock, funk, soul, blues and reggae, they perform all over the Central Coast.
Wild at Heart holds a reputation as one of the Central Coast’s premier country/classic rock music, dance, party and show bands This dynamic band includes Lisa Kincad (lead vocals), Sam Nilsson (lead guitar and vocals), Jack Aiello (percussion), Eric Rowe (keyboards and vocals) and Jon McClean (bass guitar). They play everything from RnB and folk-Americana to electronica and synth-pop.
Shane Dwight is a critically acclaimed blues maverick best known for his hit song “No One Loves Me Better,” out on Red Parlor Records. He is known for blues, rock, soul, country and a little bit of hip-hop that shows his California roots. Shane grew up on a ranch in Morgan Hill. His musical roots were FM radio, Album Oriented Rock artists. He has performed over 3,500 shows over the past 20 years, headlining at some of music’s most significant events, including Beale Street Festival, Portland Waterfront, Reno Blues Festival and Legendary Rhythm and Blues Cruise.
Known as a Mustache Harbor hardcore soft rock band, has thrilled audiences across the country with their spot-on renditions of the smoothest music from the 1970s and ’80s. The group performs with the highest level of musicianship and state-of-the-art sound and lighting.
The Chicano All Stars, led by Sam Martinez (lead vocals, guitar and percussion), The Chicano All Stars have established themselves as one of Monterey’s local legends as a favorite dance band and has been quoted to be the top Latin Rock band in the area. The band was voted the Monterey County Herald Reader’s Choice “Best Local Band” Award for 2019. They have had the pleasure of performing and sharing the stage with such names as: Los Lobos, Tierra, Malo, Tower of Power, El Chicano, La Sonora Dinamita, Jorge Santana, Brenton Wood, Eddie Money, The Turtles, Ramon Ayala, Los Tucanes, Sista Monica, The Delfonics and The Intruders.
Wine tasting
Pouring of quality wines from around the state begins at 11 a.m. and ends at 5 p.m. Saturday, and 11 a.m. to 4 p.m., on Sunday. A raffle drawing for a barrel of wine takes place at 2 p.m., on both days.
A one-day Wine Tasting Pass for one adult (does not include general admission) costs $30 (plus $3.85 online fee), with onsite purchases $40. Pouring stops one hour before festival gates close.
Participants must show a valid ID to enter the wine tasting room, and no children are allowed.
Quilt Challenge
The fourth annual Artichoke Festival Quilt Challenge invites fabric artists to win prizes and show off their quilting talents in two categories. The Judge’s Choice winner gets a $250 cash prize.
With the help of the Valley Heritage Quilt Guild from King City, the Quilt Challenge has been a resounding, creative success.
Farmers Market
Some claim this to be the “crown jewel” of the Artichoke Festival. Where else can you shop for the best locally grown, hand-harvested fresh vegetables at amazingly low prices? The farmers market includes artichokes in a variety of sizes, lettuce, spinach, cauliflower, onions, berries, peaches, apricots, plums, and so much more. The market is open Saturday and Sunday in the Salinas Room, at the festival grounds.
Ticket information
The Artichoke Festival sells a variety of ticket packages available online here. The popular Family Pack includes general admission for two adults and two children, good for one day only, with the cost $50 (processing fees).
The special It’s A Date package costs $90 (processing fees.) and includes general admission for two adults (21-over), plus two wine tasting passes. The festival also offers special rates for seniors, children and military. Parking passes are available for $15 an $20. There are no refunds.
All guests will be required to comply with current CDC, California Dept of Public Health and Monterey County public health guidelines regarding safety protocols. A clear bag policy will be enforced, with clear bags available for sale on the website store and at the gates.
California’s artichoke history began in 1922 when the first artichoke shoots were planted in Castroville. Today, more than nine decades later, nearly 100 percent of America’s fresh artichoke supply is grown in California and nearly two-thirds is grown in the small town of Castroville. The first Artichoke Festival was held in 1959 under the sponsorship of the Marinovich Marching Units, with the assistance of the Castroville Rod and Gun Club. In 1961 it was a joint venture of the Marinovich Marching Units and the Castroville Chamber of Commerce to produce a larger festival, and Sally DeSante was chosen as the first Artichoke Queen. In 1963, 1964 and 1965 it was solely sponsored by the Castroville Chamber of Commerce under the direction of the Artichoke Festival Board with Bill Price, one of the originators of the festival idea. In 1994 the Artichoke Festival became a non-profit and became the sole producer of the Artichoke Festival. The festival is currently held at the Monterey County Fair & Event Center, 2004 Fairground Road, Monterey.
Spotted wing drosophila (SWD), a small fly native to Asia that first appeared in Michigan in 2010, isn’t like most pests. Populations of crop-damaging insects tend to have distinct generations. Not SWD. Several generations overlap and build through the year, attacking vulnerable agricultural crops and wild plants. The situation has created a major challenge for the Michigan berry and cherry industries.
Spotted wing drosophila in the lab.
Rufus Isaacs, a professor in the Michigan State University Department of Entomology, was one of the first to discover the pest in the state 13 years ago. While researchers didn’t know much about SWD then, they’ve had to get up to speed quickly.
Rufus Isaacs, professor of entomology at MSU.
“SWD is so destructive because it can insert eggs into ripening fruit,” said Isaacs, whose work is supported in part by MSU AgBioResearch. “Larvae can be present in harvested fruit, which can be a big problem for producers. It is also able to reproduce so quickly to build up the population, and it can infest wild fruit outside of farms, creating a reservoir population that continually invades crop fields after they’re treated.”
After hearing about SWD arriving in California in 2008 and then being detected in Florida in 2009, concerns began to mount.
“Shortly after SWD was found in Florida, I went to a conference in Oregon where we discussed measures we may need to take to get ready for the pest,” Isaacs said. “We expected it would be in Michigan before too long.”
Sure enough, Isaacs was right. He received a grant from Project GREEEN — a partnership among MSU AgBioResearch, MSU Extension and the plant agriculture industries of Michigan — in 2010 to monitor for SWD. Isaacs worked with members of the MSU Fruit Team to set small plastic traps with holes that were filled with a cider vinegar lure.
In late 2010, SWD was collected from a site in West Michigan. At that point, the difficult work began and persists today. Research in Isaacs’ lab has been performed in partnership with mostly blueberry and raspberry growers.
The team has tested already-registered pesticides to determine their efficacy, as well as non-chemical controls such as pruning, mulching and physical exclusion methods, where growers place netting around and on top of crops as they begin to ripen.
As a result of this research, online resources have been created to assist growers with SWD identification, pesticide timing and other management strategies.
“We want to ensure we’re responsive to grower needs, first and foremost,” Isaacs said. “That’s why the pairing of research and grower education programs through MSU Extension is so valuable to our team.”
Dennis Vander Kooi, a blueberry grower and owner of Woodland Enterprises Berry Farms in Zeeland, Michigan, and his family have been working with MSU researchers for many years. He is also a board member of the Michigan Blueberry Commission (MBC), helping to set research priorities for the industry.
“Rufus is one of the nation’s leading researchers on this issue, and we’ve worked with others at MSU as well,” Vander Kooi said. “He’s run several experiments on our farm, and we’ve learned a lot from them. The MBC has supported this work and will continue to in the future as we look for effective ways to manage this pest.”
Vander Kooi said the blueberry industry is undergoing a rejuvenation in Michigan, adopting newer genetics and planting varieties that meet the demands of today’s consumers. This, in conjunction with SWD, makes it a critical time for growers as they look to protect an industry that contributes nearly $132 million to the state’s economy, according to the Michigan Ag Council.
“With the creation of the MBC in 2017, we got the opportunity to start advocating for more dollars for research, and MSU has been instrumental in that,” he said. “To date, we’ve supported more than $390,000 worth of research, much of that going to MSU, and leveraged an additional $600,000 in other funding.”
In addition to the MBC, Project GREEEN has been a significant supporter of Isaacs’ SWD efforts, along with state funding through the Specialty Crop Block Grant program and national projects funded by the U.S. Department of Agriculture (USDA).
Assessing biological control options
One of the primary challenges for scientists is focusing on immediate grower needs while also investigating long-term management tactics. It’s a monumental task to balance both simultaneously.
Marianna Szucs, assistant professor of entomology at MSU.
Alongside Isaacs, Marianna Szucs, an assistant professor in the Department of Entomology, has been exploring biological control to reduce populations in the long run. As she noted, when SWD came to the U.S., its natural predators did not.
“Anytime there is introduction of an invasive pest, one of the main issues is that the new landscape doesn’t have natural enemies for it,” she said. “They don’t come with the pest, and the native insects in the new place aren’t equipped to deal with it right away. What we wanted to know is if we exposed parasitoid wasps native to Michigan to SWD, would they begin to see them as a food source?”
A parasitoid insect lays its eggs in or on a host insect, and the developing larvae consume the host until it eventually dies.
Szucs and her team chose two parasitoid wasp species commonly found throughout North America. Researchers initially saw that attack rates in the wild were quite low, and the ability of native species to rapidly adapt to a new food source was unknown. In the lab, the parasitoids were exposed to SWD and forced to prey on them.
Within three generations of selection from a small number of parasitoids — 30 wasps or fewer — successful parasitism improved by 259% for one species and 88% for the other.
“Obviously this is an artificial scenario because we only gave them one option, and in the wild they only attack something if they know to do it,” Szucs said. “But this was a novel way to show that there is some potential to raise native parasitoids and influence their fitness to attack SWD.”
Besides improving native species, the other biological control option is to introduce natural predators. That’s what an MSU team including Isaacs has done with the samba wasp, which is native to Asia. After years of testing and applying for permits, the USDA Animal Plant Health Inspection Service and Michigan Department of Agriculture and Rural Development (MDARD) approved the release of the samba wasp in SWD-threatened locations.
The samba wasp detects already-infested fruit and targets the smallest stages of SWD larvae. Laying its eggs inside its host, the growing samba wasp feeds and ultimately kills the larvae, emerging as a wasp in roughly a month.
The team will continue to evaluate the wasps’ success in the coming growing season, as well as assessing the ability to survive Michigan winters.
“Hopefully they’re able to survive the winter and the populations are robust enough to be successful next year,” Isaacs said. “We don’t expect results right away, but this is a long-term project for us to determine if this can help reduce the need for insecticides and other management strategies moving forward.”
‘Perfect conditions for SWD’
The northwest portion of Michigan’s Lower Peninsula is world renowned for its cherry production. Growers in the Great Lakes State are responsible for 70% of the U.S. supply of tart cherries, about 80% of which are grown in the northwest Lower Peninsula. But the industry is under siege from a variety of sources, from invasive pests and climate change to competition abroad.
SWD, however, has hit the industry particularly hard. Nikki Rothwell, the coordinator of the NWMHRC and fruit specialist with MSU Extension, said this challenge affects every Michigan cherry grower.
Nikki Rothwell, coordinator of the Northwest Michigan Horticulture Research Center.
“If an orchard starts with 100 flies in mid-June, and each female can lay 300 eggs each week, even the best growers with the best programs have a hard time controlling millions of flies,” she said. “Plus, cherries are so attractive that it’s hard to monitor the populations once the fruit get ripe, which makes it hard to make good management decisions based on traditional trapping and integrated pest management strategies we’ve successfully used with other pests.”
One of Rothwell’s initial studies showed that tart cherries create the optimal conditions for SWD. While the flies leave most cropping systems during the day to avoid the hot sun, tart cherry canopies provide a cool layer of protection for them to mate and infest fruit. She found that simply pruning the trees and keeping grass clipped helps immensely.
“We did a pruning study in which we removed different numbers of branches and found that if you remove six to 10 branches in a tart cherry canopy, you can reduce SWD infestation by 40% even without insecticides,” Rothwell said. “We also showed that mowing grass short between tree rows reduced infestation.”
Recent research includes modeling SWD in cherries. Rothwell hypothesized that flies seem to be in the orchard at all times during the summer and begin to lay eggs suddenly. She believed flies were present and waiting for the right time to infest ripening fruit.
To better understand this timing, Rothwell and her team have monitored tart cherries as they ripen over the course of the growing season and brought fruit back to the lab. There, they look at when flies begin infestation. Using this information, the team is producing a model for growers that will more precisely indicate ideal timing for pesticides and other management techniques.
“We’re refining the model now, but we’re hoping to have something soon that growers can use,” Rothwell said. “The industry really depends on MSU to help work through this problem.”
Rothwell’s work has been supported by the Michigan Cherry Committee, MDARD, Project GREEEN and the Foundation for Food and Agriculture Research. — By Cameron Rudolph, Michigan State University
