UPDATED: Viticultural area is Kelsey Bench, not Kelseyville Bench.
UC Cooperative Extension study shows smoke damage to grapes not uniform across vineyards
By the time the Mendocino Complex Fires were officially contained on Oct. 4, 2018, five weeks after igniting, they had burned approximately 450,000 acres in Colusa, Lake, Glenn and Mendocino counties, making it the largest wildfire in California history, according to CalFire.
The fire not only destroyed 280 homes and other buildings, its smoke destroyed the market for wine grapes grown in vineyards near burned areas.
Fearing grapes near the fire would impart smoke flavors to the wine, some wineries rejected all fruit from nearby regions of Lake County and Potter Valley, leaving grape growers to hastily find new destinations for their 2018 crop.
“It can be difficult to determine if fruit has been compromised in quality when exposed to wildfire smoke, and whether or not smoke flavors will result in wine when fermented,” said Glenn McGourty, UC Cooperative Extension advisor in Mendocino County.
A new UC Cooperative Extension study shows wind direction and speed, temperature and a vineyard's proximity to an active fire are factors that can help growers and winemakers predict smoke damage to fruit.
“Fruit in my own vineyard, 60 feet across the street from where the fire started, had no smoke damage because the wind was blowing away from it,” McGourty said.
Due to the Mendocino Complex Fires, an estimated $41 million worth of winegrapes, which would have been sold at full price, were impacted – some were sold at a discount, some were sold to other customers, some were custom crushed, while some were left hanging in the vineyard, according to the Lake County Winegrape Commission and Mendocino County Farm Bureau.
The wine industry needed a scientific method of determining whether grapes could be made into a wine untainted by smoke. With funding from the Lake County Winegrape Commission, McGourty formed a workgroup of local growers and winemakers with Anita Olberholster, UC Cooperative Extension enology specialist in the Department of Viticulture & Enology at UC Davis, to research when fruit quality has been compromised.
“The need for industry standards regarding the impact of wildland smoke on winegrapes and the resulting wines has become even more pressing over the past few years,” said Debra Sommerfield, president of the Lake County Winegrape Commission.
Science showed the intensity, duration and timing of the exposure to wildfire smoke affects the grape's uptake. Generally, the closer to harvest, the greater risk to the fruit.
“Both the fruit and wine samples in our study showed a wide range of volatile phenol and glycocide concentrations, indicating that smoke damage to fruit was not uniform across the vineyards sampled,” McGourty said.
Volatile phenols and glycosides create off-flavors
Fresh smoke contains volatile phenols and glycosides that can affect fruit, but these chemicals tend to dissipate in the atmosphere in 1 to 2 hours. Vineyards close to actively burning fires and in the path of fresh smoke are most likely to be affected by smoke taint. Smoke that travels long distances is less likely to affect grapes and the wine made from the fruit.
The combination of volatile phenols and glycosides create “smoke taint” – both aromatic and tactile in the mouth. Wine drinkers may smell smoke or other off flavors and experience a drying of their mouth when high concentrations of the chemicals are present in wine.
“At lower concentrations, smoke taint reminds you of brett-affected wines,” Oberholster explained, referring to the yeast brettanomyces. “There is a shortness of fruit, a kind of dryness in the mouth that you know isn't normal. There may be barely perceptible aromas that aren't normal as well.”
Following wildfire smoke exposure, the researchers sampled fruit from 14 cabernet sauvignon vineyards around the viticultural areas of Lake County, including Upper Lake, High Valley, Big Valley, Kelsey Bench, Red Hills, Lower Lake and Guenoc Valley. As a control, fruit was also sampled from a Napa Valley vineyard that was not exposed to wildfire smoke.
“The volatile phenols guaiacol and 4-methyl guaiacol are detected in the fruit by gas chromatography, so it is possible to sample fruit before harvest to make picking decisions,” McGourty said. “Based on our study, berry sampling and guaiacol/ 4-methyl guaiacol analysis are useful for a quick evaluation of whether or not fruit from a particular vineyard may have the presence of volatile phenols that can potentially result in smoke-affected wine.”
Testing the fruit for volatile phenols and glycosides is both expensive and not completely predictive as standards are not well defined for damage based on smoke chemical concentration, he cautioned.
These two compounds aren't the only ones that cause smoke flavors. More than 70 other compounds in forest fire smoke can also produce undesirable flavors and odors described as “like licking an ash tray, burnt garbage, a burnt potato, a campfire that has been drenched with water.”
The taste test
To assess the levels of the compounds that produce the off-flavors, Oberholster convened a panel of 14 wine industry professionals to taste the sample wines. The wine tasters detected stronger off-flavors in the wines made from riper fruit, which also contained higher concentration of smoke compounds. Less than 6 micrograms per liter of the smoke compounds were difficult for the tasters to detect, leading the researchers to conclude they will have a minimal effect on wine quality.
Smoke from a distant fire
The scientists also looked at the influence of distance from the fire and elevation on smoke taint. They found some vineyards close to the edge of fires and immediately downwind were heavily affected, with the grapes containing high concentrations of the smoke flavor-causing compounds. But they determined elevation was not a factor in smoke flavors in wines.
Wind direction and speed, temperature and vineyard proximity to active fires are highly likely affect whether there will be smoke damage to the fruit, their research showed.
“Smoke generated in the first one or two hours from a wildfire is most damaging to nearby vineyards,” McGourty said. “Even though a vineyard may be enveloped in smoke, if the source of the smoke is from a distant fire, it will probably won't seriously damage the fruit quality because most of the volatile gases are gone.”
Lake County Winegrape Commission's Sommerfield said, “Today, the results of this study are already proving to be useful in deepening our understanding of smoke and the risks it poses to grapes and wine, in enabling grape growers and winery buyers to engage in fruitful discussions and make informed decisions, and, in turn, in helping to propel the development of industry standards and protocols.”
To read more about the study by McGourty, Michael I. Jones, Oberholster and Ryan Keiffer, see the January 2020 edition of Wine Business Monthly at https://www.winebusiness.com/wbm.
“This is a great little study, the first one that I know of that takes a systems approach to evaluating the effects of wildfire smoke,” said McGourty.
Glenn McGourty, UCCE viticulture advisor for Mendocino County, describes for Hannah Bird the UC project to analyze the effect of wildfire smoke on winegrapes.
DPR, Fresno State and UCCE create pesticide safety videos with Hmong farmers
A series of videos describing California pesticide rules and safety in Hmong is now available to view for free online. The videos were produced by California State University, Fresno and UC Cooperative Extension in Fresno County with funding from the California Department of Pesticide Regulation.
The nine-part video series – Complying with Pesticide Laws and Regulations in California – is part of DPR's mission to reach California's farming communities. The videos cover a number of topics including using personal protective equipment, understanding pesticide product labels and application permit requirements.
The innovative educational tool blends peer-to-peer communication with traditional extension methods to include the knowledge and experience of both farmers and extension experts. Hmong farmers featured in the video helped develop scenes in which they educate other farmers, purchase and use personal protective equipment, and interact with extension staff.
“We worked with Hmong farmers who are following pesticide regulations themselves, and are now giving back to educate their peers,” said Ruth Dahlquist-Willard, UC Cooperative Extension small farm advisor, who collaborated on the video production. “Their voices and expertise helped make the scenarios more realistic and accessible to other farmers in the Southeast Asian community.”
Michael Yang, longtime UC Cooperative Extension small farms and specialty crops agricultural assistant, stars in the videos, interacting with farmers based on his extensive experience and trusted relationships in the Hmong farming community, and narrating the educational content in Hmong.
“We hope the videos broaden the reach of our local extension programming to help more farmers understand pesticide regulations and avoid fines, as well as improve their safe handling, selection and use,” said Yang.
Dahlquist-Willard and Yang plan to show the videos at UC Cooperative Extension meetings with Hmong farmers and distribute copies on flashdrives to county Agricultural Commissioner's offices in Fresno County and beyond. The videos are captioned in English.
“DPR works with all types of farmers on pesticide issues and it's critical that they use these tools safely – regardless of the language they speak,” explained DPR Director Val Dolcini. “This video project, the first of its kind to use Hmong speakers, will help foster safer use of pesticides.”
The videos can be viewed at http://bit.ly/fs-dpr-hmong-pesticide-video. The modules in the series cover:
- Introduction to California Pesticide Laws
- Checking for Crops Registered on the Label
- Pests and Application Rates on the Label
- Understanding Signal Words
- Following the Restricted Entry Interval (REI)
- Following the Pre-harvest Interval (PHI)
- Knowing Common Restrictions on the Label
- Using Personal Protective Equipment (PPE)
- Pesticide Permits and Reporting requirements
The project took 700 hours over 18 months to complete, including filming and post-production. Twelve Fresno State students were also involved in producing the videos with the Hmong farmers in Fresno County. Dahlquist-Willard and Yang provided the creative direction in partnership with the farmers involved, and Fresno State's MCJ Multimedia Production Service under Professor Candace Egan brought professional video production and editing skills to make a high-quality finished product. Fresno State student video editor Mali Lee, a fluent Hmong speaker, completed the final edits of the Hmong language material.
“This was one of the most rewarding projects I have ever worked on,” said project director Bill Erysian of Fresno State. “We brought together a unique group of agricultural specialists, students, farmers and video professionals to create a high impact, professional set of educational videos on pesticide compliance for our Hmong farmers here in California.”
DPR has comprehensive pesticide safety and outreach material available in Punjabi, Spanish and English at https://www.cdpr.ca.gov/docs/whs/worker_protection.htm.
Six University of California Cooperative Extension advisor positions have been released for recruitment by UC Agriculture and Natural Resources. Glenda Humiston, UC vice president for agriculture and natural resources, is thrilled to resume strengthening the UC ANR network to address California's current and emerging needs. Due to UC ANR's budget constraints, recruitment for positions identified in the 2018 Position Call had been on hold since July.
The new positions include:
- production horticulture advisor, San Diego County
- agronomy area advisor, Merced County
- livestock and natural resources advisor, Siskiyou County
- nutrition, family and consumer sciences area advisor, San Mateo-San Francisco counties
- vegetable crops and small farms advisor, Riverside County
- pomology and water/soils area advisor, Kings County
“These were difficult decisions to make because while we need the above positions, there are many more needs for both UC Cooperative Extension specialist and advisor positions that continue to wait for additional funding,” Humiston said. “Additionally, while we have grown the UCCE specialist numbers over the last several years, the number of UCCE advisors in the field has steadily declined. For this reason, we are focusing on recruitment of UCCE advisors at this time.”
The farming community lauded adding more county-based UCCE advisors to conduct research and work with farms of all sizes to improve water efficiency, soil health and many other issues.
“Farm advisors represent a vital link from University of California research sites to the state's fields and pastures,” California Farm Bureau Federation President Jamie Johansson said, “and filling these positions will help address a statewide shortage of advisors.
“Knowledge shared by farm advisors through the decades has helped California reach and retain its position as the nation's top producer of high-quality food and agricultural products, and we need to keep that resource alive.”
In January, UC ANR's Human Resources unit will begin recruitment planning for the newly released UCCE advisor positions, which will be posted at https://ucanr.edu/About/Jobs.
Currently they are working on recruitment for the following positions from previous calls:
- viticulture advisor for Kern County
- climate & agriculture project scientist
- human-wildlife conflict advisor for the San Mateo/San Francisco Bay Area
- 4-H STEM academic coordinator
- small farms and specialty crops assistant specialist for Fresno County
“I hope to release five or six more UCCE positions in the spring/summer,” Humiston said. “This is possible, in part, due to the advance notice provided by individuals planning to retire June 2020. In addition, we will complete recruitment of other academic positions currently advertised, including those that are funded through partnerships.”
UC Agricultural Issues Center has released new studies estimating the cost and returns of establishing an almond orchard and producing almonds for three growing regions of California.
“These cost studies are valuable for agricultural producers all along the continuum – growers considering entering into a new crop production business, less experienced growers, and those with decades of experience,” said Emily Symmes, UC Cooperative Extension integrated pest management advisor for the Sacramento Valley. “The information in these cost studies allows growers to evaluate their production practices and associated costs relative to an exemplary hypothetical orchard specific to their geographic region, and can help with development of business models, crop insurance and lending.”
In 2018, almonds ranked third among California commodities with almond growers receiving nearly $5.5 billion in cash receipts.
The cost analyses are based on hypothetical farming operations of well-managed almond orchards, using cultural practices common to the region. Local growers, UC Cooperative Extension farm advisors and supporting agricultural representatives provided input and reviewed the methods and findings of the studies.
“The recent almond updates for the Sacramento and San Joaquin valleys reflect costs associated with the continually evolving conditions facing agriculture,” said Symmes, who co-authored the almond cost studies. “Some of the notable updates include labor, irrigation and pest management costs – all integral to producing and delivering a high-quality crop.”
The researchers based one study in the Sacramento Valley, one in the northern San Joaquin Valley and the other in the southern San Joaquin Valley.
The southern SJV study is based on an orchard that uses double-line drip irrigation, whereas the other two locations use microsprinkler irrigation. All are multi-year studies, estimating costs from removal of the previous orchard, through almond orchard re-establishment and the production years. The economic life of the orchards used in these analyses is 23 to 25 years.
Navel orangeworm (NOW) is a major pest in almond production; Symmes and her co-authors describe in detail the pesticide applications and winter sanitation methods for each location for NOW control and include the costs.
The authors describe the assumptions used to identify current costs for orchard establishment, almond production, material inputs, cash and non-cash overhead. A ranging analysis table shows net returns over a range of prices and yields.
The new studies are titled:
- Sample Costs to Establish an Orchard and Produce Almonds in the Sacramento Valley - 2019
- Sample Costs to Establish an Orchard and Produce Almonds in the Northern San Joaquin Valley - 2019
- Sample Costs to Establish an Orchard and Produce Almonds in the Southern San Joaquin Valley - 2019
The studies are available for free download at the UC Davis Department of Agricultural and Resource Economics website at http://coststudies.ucdavis.edu. Sample cost of production studies for many other commodities are also available on the website.
For additional information or an explanation of the calculations used in the studies, contact Donald Stewart at the UC Agricultural Issues Center at (530) 752-4651 or firstname.lastname@example.org. To contact a local UC Cooperative Extension advisor, find the UCCE office in your county at http://ucanr.edu/County_Offices. The Agricultural Issues Center is a statewide program of UC Agriculture and Natural Resources.
California's working landscape and the industries associated with agriculture and natural resources contribute significantly to the state's economy, according to a new study by the California Community Colleges Centers of Excellence for Labor Market Research, California Economic Summit and the University of California's Division of Agriculture and Natural Resources.
“When people think of California's economy, they think of entertainment, information technology and other industries. They may not think of working landscape,” said Glenda Humiston, University of California vice president, agriculture and natural resources. “People may be surprised to learn that California's working landscape accounts for 6.4% of the state's economy, supports more than 1.5 million jobs and generates $333 billion in sales.”
To measure the economic impact of the working landscape, researchers from the Centers of Excellence, California Economic Summit and UC Agriculture and Natural Resources analyzed federal data associated with employment, earnings and sales income of the nine segments that are essential to the working landscape: agricultural distribution, agricultural production, agricultural processing, agricultural support, fishing, forestry, mining, outdoor recreation and renewable energy.
Their analysis of 2018 data from the North American Industry Classification System showed the value of the working landscape in California comes in ahead of the health care, real estate, retail and construction industries. The top five economic drivers were government (21.9%), manufacturing (10.2%), information (9.3%), professional, scientific and technical services (7.5%), and finance and insurance (6.4%).
The researchers found the nearly 70,000 businesses associated with the working landscape paid $85 billion to workers in 2018 and generated $333 billion in sales income. In terms of job numbers, earnings, sales income and number of establishments, four segments dominate: agricultural distribution, agricultural production, agricultural processing and agricultural support.
Agricultural production provides the greatest number of jobs, more than 325,000, and generates the second highest sales income, $61 billion in 2018. Although agriculture accounts for 79% of working landscape sales income, it is important to note that other working landscape segments are still sizeable when compared to the rest of the nation.
In addition to evaluating the contribution of the industries to the state's economy, the researchers measured the importance and impact of the nine working landscape segments by region. For example, some segments, although relatively small in terms of employment or sales income, are cornerstones of local economies and play a critical role in the livelihoods of communities.
The Los Angeles/Orange County region, the San Francisco Bay Area, and San Joaquin Valley have the greatest concentration of jobs for agricultural distribution, agricultural processing, agricultural support, mining and renewable energy. The San Joaquin Valley leads in agricultural production, followed by the Central Coast. Los Angeles/Orange County has the most forestry, fishing and outdoor recreation jobs.
This report does not include economic values for ecosystem services provided by California's working landscape such as clean water, nutritious food and a livable climate, or intangible goods that contribute to human well-being, such as recreation, aesthetic inspiration and cultural
To read the report “California's Working Landscape: A Key Contributor to the State's Economic Vitality,” visit http://ucanr.edu/WorkingLandscape. A one-page executive summary is available at http://bit.ly/2WTA7Vz.