Grape & Wine Magazine - May 2023

Page 1

A PET Project. Lightweight Plastic Bottles Make Winery Inroads, but Glass


Photo courtesy of J. Ramos.
Continues Dominance
for Selling Your Vineyard or Winery Volume 1: Issue 3
Heroes Considerations

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Christophe Bertsch Laboratoire Vigne, Biotechnologies et Environnement, Université de HauteAlsace, Colmar, France

Vicky Boyd Contributing Writer

Natalie Collins President, California Association of Winegrape Growers

Sibylle Farine

Ph.D., Laboratoire Vigne, Biotechnologies et Environnement, Université de HauteAlsace, Colmar, France

Marc Fuchs

School of Integrative Plant Science, Cornell University

Julie R. Johnson

Contributing Writer

Catherine Merlo Contributing Writer

Samuele Moretti

Ph.D., Laboratoire Vigne, Biotechnologies et Environnement, Université de Haute-Alsace, Colmar, France

Cecilia Parsons Associate Editor

Steve Pastis Contributing Writer


Surendra Dara Director, North Willamette Research and Extension Center

Kevin Day UCCE Pomology Farm Advisor, Tulare and Kings Counties

Elizabeth Fichtner UCCE Farm Advisor, Kings and Tulare Counties

Katherine Jarvis-Shean UCCE Orchard Systems Advisor, Sacramento, Solano and Yolo Counties

Steven Koike Tri-Cal Diagnostics

Jhalendra Rijal UCCE Integrated Pest Management Advisor, Stanislaus County

Mohammad Yaghmour UCCE Area Orchard Systems Advisor, Kern County

The articles, research, industry updates, company profiles, and advertisements in this publication are the professional opinions of writers and advertisers. Progressive Crop Consultant does not assume any responsibility for the opinions given in the publication.

January 2023
04 08 16

A PET Project Lightweight Plastic Bottles Make Winery Inroads, but Glass Continues


Corey Manning, co-owner of Chateau Diana Winery in Healdsburg, Calif., knew he had to do something because he was paying nearly as much to ship 750 ml bottles of wine direct to consumers as he was to make the wine. He turned to the manufacturer Amcor Rigid Packaging, which produces polyethylene terephthalate, or PET, bottles.

Manning said he’s been able to reduce his shipping costs by replacing glass bottles with those made from PET, and he hasn’t received push back from customers. They won’t replace glass bottles entirely, as Château Diana continues to use glass for more premium wines. But Manning said 750 ml filled PET bottles, which weigh about one-third

of comparable filled glass bottles, are a good fit for their value-priced lines and direct-to-consumer business.

Even with some wineries looking to alternative packaging for some markets, Scott DeFife, executive director of the Glass Packaging Institute, said his members haven’t seen a decrease in demand for glass bottles. In fact, DeFife said, just the opposite is true with domestic glass container plants shipping about 1.82 billion wine bottles through November 2022. That’s up 17 million bottles from the same period through November 2021. The vast majority of those were 750 ml.

“The industry is doing really well,” he said.

DeFife, who represents the North American glass container industry, said most of his members continue to address weight and shipping concerns by manufacturing lighter-weight bottles. Compared to 20 years ago, today’s bottles are 30% to 40% lighter, he said.

“Data shows the majority of the 750 ml bottles are actually lightweight and medium-weight bottles,” DeFife said. “So the production of lighter-weight glass bottles is up significantly from where it was, and in many cases, it’s the majority of bottles you can get.”

But freight costs are just one part of the sustainability equation, he said. One of glass’ attractions is its physical composition, which acts as a natural barrier to prevent oxidation, product interactions or external influences. For wines designed to age in the bottle, DeFife said this is a big draw.

“Anything that’s going to age, you’re going to want it in glass, and that goes to waste, food waste and shelf life, which are also important to sustainability,” he said.

Reduce, Reuse, Recycle

Glass also can be readily recycled and made into new bottles countless times without loss of quality or purity. DeFife

4 Grape & Wine Magazine May 2023
PET bottles, particularly the 187 ml size (center), have gained popularity in some market sectors because of their light weight, portability and cost (photo courtesy Amcor Rigid Packaging.)

said. Raw materials used to make glass include readily available sand, soda ash, limestone and cullet, an industry term for recycled glass. And up to 95% recycled glass can be used in place of raw materials to make new containers.

DeFife, who also serves as president of the non-profit Glass Recycling Foundation, admitted the California statewide consumer recycling rate for wine and spirits bottles could be better. But he pointed to Senate Bill 1013, which Gov. Gavin Newsom signed in September 2022, as a way to address that.

Beginning Jan. 1, 2024, the bill establishes a 10-cent California redemption value, or CRV, on most wine and spirits bottles. It also sets a 25-cent CRV on difficult-to-recycle wine packaging, such as boxes, bladders and pouches.

The legislation’s authors, President Pro Tempore Toni G. Atkins, D-San Diego,

and Sen. Bill Dodd, D-Napa, said they wanted to enhance wine and spirits bottle recycling. Those containers currently are not covered by the California Beverage Container Recycling and Litter Reduction Act passed in 1986.

The lawmakers estimate that California generates more than 500 million wine and spirits bottles annually, with less than 30% being recycled and more than 300 million ending up in landfills.

DeFife, who was involved in bill negotiations on behalf of his members, said it can only help but enhance the industry’s sustainability efforts.

“We think that the West Coast and the wine regions of the country are going to see some of the most sustainable glass bottles in North America,” DeFife said. “The recycled content rate is high and growing, and the recovery rates and the recycling rates are going to go up to well above national average.”

Similar Path to Screw Caps

Manning said he likes to compare the industry’s current packaging evolution to where it was in the 1990s when screw caps started making inroads. Back then, many people criticized the closures. But today, consumers widely accept them on many types of wines and in many price sectors.

“We were one of the first people to jump on screw caps because it made sense for what we were doing,” he said. “We were trying to develop an economical everyday wine that people could enjoy. Moving ahead into this, it’s the same

premise, the same experiences. We saw potential pushback, but our position was we want to try it. We live in California, and we’re really lucky to benefit from the economics. But people in the rest of the U.S. don’t have the money to spend $25 for a bottle of chardonnay.”

For more than a decade, many wineries have slowly switched their single-serve offerings from glass bottles to containers made from alternate materials as a cost-cutting measure. PET bottles’ popularity has grown because they have the same shelf appeal as glass but with less weight, said Matt Shaieb, commercial sales director for Amcor Rigid Packaging.

By nature, PET is a porous material, which can potentially lead to oxidation and an off-flavor over time. To address that, he said Amcor applies the ultra-thin KHS Plasmax silicon oxide barrier coating to the inside of their containers. A glass-like material, Plasmax is Food and Drug Administration-compliant and fully recyclable.

Manning said he, too, had heard concerns about PET bottles imparting an off-taste to wine. But in taste tests where wine was stored for up to a year in the containers, he said they found no sensory issues. Manning said they haven’t gone past a year because most of their value-priced wines are consumed less than a year after bottling.

Because of their portability, the single-serve 187 ml size has become popular for use on airplanes, in the hospitality industry, in sports venues and for other activities where glass isn’t convenient. The bottles are about onesixth the weight of comparable-sized glass containers, Shaieb said.

In addition, larger sizes of PET bottles have made inroads into the spirits business. But 750 ml PET bottles are relatively new to the wine industry.

The potential for cost savings seen with 187 ml bottles was what attracted Chateau Diana to try PET for industry-standard 750 ml bottles.

Manning said a case of wine using

6 Grape & Wine Magazine May 2023
750 A small but growing number of wineries are exploring 750 ml PET bottles for value-priced wines or because of their lighter weight and transportation advantages (photo courtesy Amcor Rigid Packaging.) Glass bottles remain an industry stalwart because of the material’s inherent physical characteristics such as impermeability and lack of chemical reactions. This allows wine to be aged in bottles for several years (photo courtesy Glass Packaging Institute.)

ml glass bottles weighs 36 pounds compared to 13 pounds for a case of filled PET bottles. He’s also able to put 70 cases of PET bottles on a pallet compared to 56 cases of filled glass bottles. Case dimensions have shrunk without the cardboard inserts needed to keep glass bottles from knocking against each other.

At the same time, a typical semi-truck can hold 2,000 cases of PET bottles compared to 1,230 cases of filled glass bottles bottles. Other factors constant, Manning said they’ve seen an 8% savings just by switching packaging.

Appealing to a New Generation

Much like early screw cap use, Manning said he’s heard industry concerns about potential customer pushback with PET bottles. But he really hasn’t experienced it in his business.

Based on customer demographics at the Chateau Diana tasting room, Manning said he’s seeing an influx of much younger drinkers aged 21 to 35 years

old. This is the same generation that grew up with bottled water, so they’re comfortable with plastic containers.

“It’s a huge group that the wine industry has been trying to figure out for years,” Manning said. “They’re more apt to drink in non-traditional settings, and I also think that cost-wise, it makes sense for them.”

Sustainability also resonates strongly with Generation Z, as these newly minted adults are dubbed, and Shaieb said PET bottles have a good story. Compared to other alternative packaging such as aluminum cans, he said PET containers have a 30% lower carbon footprint.

And unlike bag-in-a-box containers where the bladder must first be removed and separated from the cardboard exterior, Shaieb said PET containers can be directly recycled into programs that accept the international recycling triangle symbol for Plastic No. 1.

Senate Bill 1013, effective Jan. 1, 2024, would add a 10cent deposit to most wine and spirits bottles, enhancing recycling and the glass industry’s sustainability efforts (photo by V. Boyd.)

Despite his adoption of PET bottles for some market sectors, Manning said he believed glass bottles won’t fade away.

“We’re still using glass bottles, and they’ll still be around,” he said. “But I do think there’s room in the wine business for lots of people to try different things.”


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Wine Country Heroes

One is a native son who grew up with California farming in his blood. The other is originally from the East Coast and has practiced law for decades in the Golden State.

On the surface, vineyard manager Dana Merrill and attorney Jeanne Malitz might seem like polar opposites. But their diverse lives converged earlier this year when they were honored with the two highest awards given by the California Association of Winegrape Growers.

Merrill received the Grower of the Year Award, CAWG’s top honor. The award recognizes excellence in viticulture and management as well as innovation and industry leadership.

CAWG honored attorney Jeanne Malitz as Leader of the Year for helping ag employers with the H-2A program (photo courtesy Malitzlaw.) ContinuedonPage10

Grower of the Year award winner Dana Merrill is “a pillar in the winegrape industry,” says the California Association of Winegrape Growers (photo courtesy Mesa Vineyard Management Co.)

8 Grape & Wine Magazine May 2023
Through distinctly different roles, Jeanne Malitz and Dana Merrill earn the appreciation of California’s winegrape industry.
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Malitz was named CAWG’s Leader of Year for her efforts, extending to the national level, to help winegrape growers and agricultural employers with the federal H-2A guest-worker visa program.

CAWG recognized the two leaders at the Unified Wine & Grape Symposium Jan. 24 in Sacramento. CAWG President Natalie Collins singled out Merrill as “a pillar in the winegrape sector, from his dedication to sustainable farming to his innovation in developing new growing techniques.”

Collins acknowledged Malitz as “the industry’s go-to attorney on all H-2A matters. In a time when growers are continuing to look at diverse avenues to hire labor, Jeanne’s advice has been instrumental.”

Like winegrapes themselves, Merrill and Malitz have emerged from their own unique terroirs, with their diverse backgrounds and expertise producing big benefits for California agriculture.

From Federal Litigation to H-2A

Boston-born Malitz worked for a Wall Street law firm, then became a federal litigator before coming to California in the 1990s. She found her calling in employment and immigration law while working for a large law firm in San Diego.

“I loved it because it was people focused,” she said.

In 2002, the East Coast native established her own practice, Malitzlaw, Inc., in San Diego. Today, Malitz and her 12 employees work with clients in 11 states. The firm focuses on employment-based immigration matters, emphasizing permanent and temporary labor certification for agricultural employers. Her practice also counsels on employment verification, including e-Verify and I-9-related issues. It’s high-volume, fast-paced, often stressful work.

“We work with thousands of farmworkers and their employers,” she said. “We sometimes have 30 cases due on a single day.”

The Good and Bad of H-2A Malitz’s assistance in helping winegrape employers maneuver through H-2A’s legal and administrative paperwork and requirements has become more urgent as the need for foreign workers grows more acute.

Malitz cites a combination of factors for the labor shortage: domestic workers leaving the agricultural industry, the workforce aging out and greater enforcement of I-9 requirements and at the border, which reduces the pool of illegal immigrants who would go into agriculture.

“There aren’t even enough illegals to do agriculture,” said Malitz. “With all the enforcement, you don’t really want an illegal workforce, which is why people do H-2A. It’s reliable, consistent and dependable, versus a domestic workforce, which is very unstable.”

At the same time, Malitz acknowledged the H-2A program “is cumbersome and very expensive” for ag employers. To participate, they must work with multiple federal and state agencies. They’re required to offer free housing to their H-2A employees. Another problem is defining “the area of intended employment” and workers’ commuting distance.

Further challenging H-2A participation is the requirement that program workers must be paid $19.65 an hour for non-harvest work, $1 more than California’s regular H-2A rate. It’s a contentious issue.

“I think we’re going to see litigation on

this prevailing-wage issue in the winegrape industry,” said Malitz.

As a result of these hurdles, only a fairly low percentage of winegrape employers use H-2A, said Malitz. She advises those who do participate to apply well in advance of when they think they’ll need H-2A workers.

“Things can get delayed because of so many government agencies,” she said. “Employers need to be organized for us to be organized. They’ve got to set their expectations. They not only have to know the rules, they have to follow them.”

Malitz believes those who use the H-2A program “are the best employers who try to do everything right. They’re good players. That’s a message that never seems to get across to the public.”

Central Coast Wine Industry Pillar

Some 330 miles to the north, at his headquarters in Templeton, Calif. near Paso Robles, Merrill focuses on developing and managing winegrape vineyards. His Mesa Vineyard Management Company oversees 12,000 acres of winegrapes. While his son, Matthew, has taken over as general manager, Merrill remains company president and deeply involved in strategic planning and problem-solving.

Merrill is a seventh-generation Californian whose ancestors came from Spain in the 1700s to help build the missions. He grew up on his grandfather’s ranch in Santa Ynez in Santa Barbara County. After earning a degree in agricultural business management from California

10 Grape & Wine Magazine May 2023
The H-2A guest worker program is both necessary and cumbersome, say Malitz and Merrill (photo courtesy Paso Robles Wine Country Alliance.)

Polytechnic University at San Luis Obis po, Merrill and his brother leased land to farm. That venture wasn’t financially successful. He was later hired by a large vineyard management and development company in Monterey County. That

winegrape sales for 30 different grape varieties each year.

Merrill, along with his wife Marsha and son Matthew, also launched Pomar Junction & Winery in 2008 to showcase estate wines from their own 120-acre Templeton vineyard in the Paso Robles appellation. Named for a nearby convergence of two old railroad lines, the winery features a Sante Fe caboose in its logo. The Merrills closed their winery when the pandemic hit but maintain a private tasting room at their main ranch.

All those moving parts take unique skills, and Merrill has them. He de-

“generally positive attitude and dry sense of humor,” who’s budget-oriented but

May 2023 11
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Merrill’s positive outlook for California’s winegrape industry stems from the state’s ideal growing regions for high-quality wines. “Quality always sells,” he says (photo courtesy Paso Robles Wine Country Alliance.)

Those traits were put to use when Merrill served as CAWG’s board chairman from 1999-2001 and as the first chairman of the California Department of Agriculture’s Pierce’s Disease and Glassy-Winged Sharpshooter Board. He was a charter board member of the Central Coast Vineyard Team. Merrill also was named 2012 Wine Industry Person of the Year by the Paso Robles Wine Country Alliance as well as the San Luis Obispo County Farm Bureau.

Business Challenges

Still, life returns to normal after the awards presentations. Like Malitz, Merrill wrestles with labor issues. His company relies on hundreds of seasonal people, but it’s difficult to find adequate labor. He has long used third-party labor contractors but recently began using the H-2A program too. That’s on top of Mesa Vineyard Management’s 85 full-time employees.

But the challenges don’t stop with labor. Merrill points to California’s chronic water shortages, the vine mealybug, fewer approved labels for chemical use, and inflation. This winter’s storms also caused flooding and erosion in some of the vineyards he manages.

Local water-well issues also challenge the Paso Robles area, which is all groundwater-supplied. Over the past 20-plus years, Merrill has watched the area expand to 40,000 vineyard acres and more than 200 wineries, creating a wine-centric mecca that draws tens of thousands of people each year. Further bolstered by hotels, restaurants and tasting rooms, Paso Robles has been transformed into a cultural center.

But that growth has created land- and water-use challenges for commercial winegrape producers, who often operate adjacent to rural residents living on one- or two-acre lots. In fact, groundwater shortages have led to a moratorium on new irrigated farmland in the Paso Robles area.

“I have spent significant time working

with others to form the Estrella-El Pomar-Creston Water District in the west half of Paso Robles Basin,” said Merrill. “Trying to figure out how to comply with the Sustainable Groundwater Management Act and deal with less common cohesiveness everywhere makes a tough job even harder.”

Also high among his worries is the rising cost of wages. Mesa Vineyard Management has seen three state-mandated 8% increases over three consecutive years. On top of that are future wage increases tied to annual inflation. Those wage escalations “rippled through our company,” Merrill said. “When the lowest-paid people get a raise, everybody above them expects a raise too.”

Technology and Mechanization

Such labor problems have pushed Merrill and his team to use more mechanization and technology. Machines are doing more vineyard pruning, harvesting, tending of canopies and moving wires. Its grape harvesters are now programmed to calculate yields and unharvested blocks needed to fulfill grape contracts. Mesa Vineyard Management also has adopted more stringent irrigation management to comply with SGMA. The company has increased its precision application of chemicals.

It further relies on electronic trackers placed on its trucks, grape harvesters and other equipment. That’s eliminated the need for employees to contact vineyards and wineries to locate vehicles.

“Who knows what’s ahead, but more tech is a given,” Merrill said.

Despite the challenges, Merrill’s outlook remains positive in part due to California’s ideal growing regions and their high-quality wines. “Quality always sells,” he said.

Merrill and Marsha, married for 48 years, just bought a vacation house in Costa Rica. He hopes to spend more time there, improving his Spanish-speaking skills and enjoying his favorite wine, a Merlot from his own Pomar Junction label. Seeing the next generation succeed also remains a goal for him. His advice to younger winegrape growers and managers?

“Learn all you can,” he said, “and figure there will be many twists and turns to your career.”

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12 Grape & Wine Magazine May 2023
At this year’s Wine & Grape Symposium, Jeanne Malitz (left) receives a proclamation from California State Assembly member Tasha Boerner Horvath (center). CAWG President Natalie Collins is at right (photo courtesy CAWG.)
Dana Merrill accepts CAWG’s Grower of the Year Award from President Natalie Collins at the Unified Wine & Grape Symposium Jan. 24 (photo courtesy CAWG.)
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Considerations for Selling Your Vineyard or Winery

If you are planning to sell your vineyard or winery, the first thing to consider is the way it presents itself to a prospective buyer.

Appearance is “extremely important as you never get a second chance at a first impression,” said Joe Ramos, co-director of the Vineyard and Winery Division at Berkshire Hathaway HomeServices California Properties in Los Olivos, Calif. “Whether you’re selling a vineyard or winery, or a residential property, it’s ‘Salesmanship 101’ to have the property looking its very best.”

“Anytime you put a property up for sale, you want it to look sharp,” agreed Preston Smith, owner-broker at Prolacom Realty Advisors in Santa Rosa, Calif. “People are looking for cleanliness and sanitary conditions. You want your vineyard to be clean and well-manicured. The rows should look nice and clean.”

“At a bare minimum, the property should be cleaned up and any necessary maintenance attended to,” said Ramos. “We highly recommend our seller clients conduct presale inspections so issues regarding safety, health and permit violations are resolved prior to going on the market. Everything should be in working order.”

Smith noted when a prospective buyer sees something needing repair, “they automatically expect to pay twice what it

actually costs to fix it.”


Buyers need to know that the wells and pumps can adequately produce water for the property’s needs, said Smith.

Ramos said presale inspections should include a general well inspection that measures flow rate (GPM), depth of the well, water level and a drawdown test to determine the recharge rate. He recommends water quality tests, which include bacterial and chemical testing, be conducted.

“If the well is also supplying water to a dwelling, a potability test should be conducted to ensure the water is drinkable,” he said. “The results of these inspections should be readily available to all prospective buyers.”


“It’s very important that all your paperwork be in order and documentable,” said Smith. This includes weigh tags, “so you can prove to a buyer what the vineyard has been producing for the past five years.”

“Apart from local permits, the two major ones are obtaining permission from the Alcohol and Tobacco Tax and Trade Bureau (TTB), and [in California] a California Alcohol Beverage Control (ABC) Type 02 Winegrowers license,” said Ra-

mos, who suggests that sellers understand everything they can about their property.

“Sellers should become experts on what they’re selling and really know the ins and outs of their property because if they don’t, buyers will become the experts and use the information they learn to drive the price of the property down in secondary negotiations,” he said.


“It is better to include the equipment and offer the property as ‘turn-key’ as possible,” said Ramos. “Many buyers are just beginning their path in the wine industry and may not know everything that is needed to produce wine. Having a farm and winery that includes all the equipment needed breaks down a big barrier to entry and allows them to step into a vineyard and winery with relative ease. The equipment is often more valuable to an incoming buyer than it is in the used equipment market.”

Including equipment in a sale depends on what the seller plans to do, according to Smith. If the seller is only selling one of several properties, he will probably not include the equipment. Often, a new vineyard manager will bring in their own equipment, lowering the value of the seller’s items in the sale.


There are different opinions on the

14 Grape & Wine Magazine May 2023
It is recommended to sell a vineyard or winery in late spring as opposed to holiday times of year.

importance of having experienced and competent employees. Ramos considers them “invaluable” to a sale.

“Working properties often have an existing human element that should stay in place,” he said. “This includes vineyard managers, ranch managers, tasting room staff, other employees and third parties who assist immensely in the day-to-day operations, know the properties and business intimately, and keep properties operating smoothly. It’s important to understand the full scope of the day-today operations and what it entails before diving into a working property. It’s also important to tread softly upon entry and not try to reinvent the wheel.”

However, Smith explained the importance of employees to a sale depends on the buyer. If a 300-acre vineyard is being sold to a supergrower, “they already have a staff and their own vineyard management.”

Brands and Bottom Line

The quality of a winery’s product “is paramount, especially when that product leads to the formation of a reputable brand and high demand,” said Ramos.

“If you have a high-end brand, a bestof-show, award-winning wine, you can command a higher price,” said Smith. “If you have Safeway and Costco buying your wines, you can command a higher price.

“Your bottom line is important in the evaluation of a winery,” he added. A prospective buyer wants to know “the net dollar amount they can depend on.”

“Recent profits are very important to the marketability of the property and operation as they provide a road map of what a buyer can expect when they take ownership,” said Ramos. “This allows incoming buyers an opportunity to plan better and manage expectations. However, a successful business often comes at a higher cost than businesses that are losing money. If the business has experienced losses, especially over a long period of time, it is often recommended the seller not include the business and simply focus on the real property component.”

However, the bottom line may not matter to the sale.

“Oftentimes, buyers are purchasing the property as a heritage property with the intent that the venture be multi-generational,” said Ramos. “Many buyers want to craft a business that is personal to their tastes and vision, including branding and the wine’s characteristics. In these instances, the business is less important because the buyer desires to form the business from the ground up.”

Tasting Rooms and Homes

“Wineries with a tasting room are often easier to sell because the buyer pool is larger,” said Ramos. “Many buyers enjoy the social aspect of the wine industry, and there’s no better way to interact and mingle with patrons than in a tasting room environment.”

“Homes are secondary,” said Smith, who added if the property has a home or two, they are generally for employees.

Ramos believes some attention should be given to any homes on the property but urges caution before making any improvements.

“We typically recommend being careful as many buyers have their own aesthetic preferences and may not like what the seller decides to do, oftentimes at considerable costs,” he said. “If improvements are going to be made, focus on items that will provide the biggest bang for your buck. These might be particular items that really date the house and scream that it’s due for a major overhaul. Often, these are features that were popular 10 or more years ago and have fallen out of favor. If you have purple carpet, that may be an item worthy of tackling. Remember to put your personal preferences aside and take a more neutral route. A quick Google search can help by providing trending materials, color schemes and ideas.”

When to Sell

“The holidays are horrible,” said Smith, explaining when definitely not to sell. “People are home with their families. If you put property for sale in November, you’re not going to get activity until Janu-

ary when people are back in business.”

He advises sellers, if possible, to put properties on the market in late spring. “May and June are always nice,” he said. “It’s always good after the vines leaf out.”

But spring brings another challenge.

“As spring begins, so do the costs,” said Smith, raising another major consideration in a sale. “Who’s going to get the crop?”

When selling a vineyard, it’s important to determine whether the buyer or seller gets the crop, and who pays the expenses to grow it.

Ramos recommends prospective buyers evaluate things such as acreage, size of the vineyard and winery, location, varietals, soil, water, weather, American Viticultural Areas, pedigree of neighboring vineyards, management, condition of the vines, entitlements granted under the permit and whether there is disease or a virus present.

Comments about this article? We want to hear from you. Feel free to email us at

May 2023 15
If you are planning to sell your vineyard or winery, the first thing to consider is the way it presents itself to a prospective buyer (all photos courtesy J. Ramos.) It is good to include any winemaking or vineyard equipment in a sale to ease the buyer in.


Leafroll is the most widespread and devastating viral disease of grapevine worldwide. It reduces yield, delays fruit ripening, increases titratable acidity, lowers sugar content in fruit juices, modifies aromatic profiles of wines and shortens the productive lifespan of vineyards. The economic cost of leafroll is estimated to range from $12,000 to $92,000 per acre of ‘Cabernet Sauvignon’ in California (Ricketts et al. 2015).

Grapevine leafroll-associated virus 3 (GLRaV 3) is the most dominant virus in leafroll-diseased vineyards. This virus is phloem-limited and transmitted by vegetative propagation and grafting as well as by several species of mealybugs. Mealybugs are sap-sucking insects and pests of grapes. At high densities, mealybugs can cause complete crop losses, rejection of fruit loads at wineries and death of spurs, although small infestations may not inflict significant direct damage. Several mealybug species feed on grapevines in California vineyards, including vine mealybug (Planococcus ficus), grape mealybug (Pseudococcus maritimus), obscure mealybug (Pseudococcus viburni) and longtailed mealybug (Pseudococcus longispinus) (Daane et al. 2012). Vine mealybug is an invasive species and the most damaging of the mealybugs that

occur in California vineyards. Unassisted, mealybugs have limited mobility, but immature instars (crawlers) can be dispersed over long distances by wind and other means.

GLRaV-3 is acquired within one hour or less when instar mealybugs feed on infected grapevines. The virus is transmitted in a similar short time to healthy grapevines (Tsai et al. 2008). Following inoculation of healthy grapevines, it takes at least three months for GLRaV-3 to be detected in inoculated grapevines using laboratory-based diagnostic assays and one year for inoculated vines to exhibit typical leafroll disease symptoms in the vineyard (Blaisdell et al. 2016). In most diseased vineyards, the dynamics of leafroll spread is influenced by virus incidence and mealybug population density (Arnold et al. 2017, Cooper et al. 2018). In addition, the two adjacent vines to an infected vine are more likely to become infected over time than their counterparts located across the row, suggesting a predominant within-row virus spread and a spatial dependence for secondary spread (Bell et al. 2018).

Current Management Options

There is no cure for leafroll in diseased vineyards. However, the disease can be managed by reducing the number

of infected vines and by controlling mealybug vector populations. For example, the elimination of diseased vines (a strategy known as roguing) and their replacement with clean vines derived from virus-tested nursery stocks that test negative for economically relevant viruses, including leafroll-associated viruses, reduce the incidence of GLRaV-3 and limit its secondary spread in vineyards (Bell et al. 2018, MacDonald et al. 2021).

Spatial Roguing, a New Response to Leafroll

Modelling leafroll disease spread in relation to economic factors predicted when roguing diseased vines, if disease prevalence is less than 25% (Ricketts et al. 2015) and two immediate within-row neighboring vines on each side, regardless of their disease status (for a total of five vines in the case of one infected vine), a strategy referred to as spatial roguing is more effective at reducing the level of virus inoculum in a diseased vineyard than roguing only diseased vines (Atallah et al. 2015). This strategy was inspired by the fact that 1) mealybug crawlers are more efficient vectors of leafroll viruses than adults; 2) crawlers are more likely to move along rows than between rows; 3) leafroll spread predominantly occurs at a short spatial

16 Grape & Wine Magazine May 2023
By MARC FUCHS | School of Integrative Plant Science, Cornell University Fruits of a healthy ‘Cabernet franc’ vine (all photos courtesy M. Fuchs.)

scale; 4) a healthy-looking vine that is adjacent to a diseased vine may be infected without exhibiting disease symptoms; and 5) disease symptoms are only apparent at least one year after inoculation by viruliferous mealybugs (Blaisdell et al. 2016). Predictive models suggested that spatial roguing targeting symptomatic vines and their four immediate neighbor vines, two on each side, would be of statistically significant greater economic value than spatial roguing targeting symptomatic vines and their two immediate neighbor vines, one on each side. Simulations further predicted that a nonspatial strategy targeting only diseased vines is less effective and more costly than spatial roguing (Atallah et al. 2015).

We applied spatial roguing in a ‘Cabernet franc’ vineyard with overall low leafroll virus prevalence (5%) and a low grape mealybug population density in New York and tested its effectiveness at reducing the incidence of leafroll disease and slowing virus spread (Hesler et al. 2022). Four treatments were applied to select vine panels from 2016 to 2021: (1) spatial roguing only, (2) spatial roguing in combination with insecticide applications targeting grape mealybugs, (3) insecticide applications only (no spatial roguing), and (4) no spatial roguing and no insecticide intervention (the untreated control). Results showed that virus incidence was reduced from 5% in 2016 to less than 1% in 2020 to 2021 in both spatial roguing treatments. Among vines in the insecticide-free, non-rogued control treatment, virus incidence increased from 5 to 16% from 2016 to 2021 (Hesler et al. 2022). Insecticides applied in 2016 to 2021 helped significantly reduce grape mealybug populations to near zero annually, while populations in the untreated control vines were 57- to 257fold higher during the same period (Hesler et al. 2022). This work validated spatial roguing as a leafroll disease manage-

ment response in a vineyard with low disease incidence and low grape mealybug abundance.

Spatial roguing adds to the overall cost of vineyard maintenance. Revenue losses directly related to spatial roguing were estimated in our study at $5,565 per acre over six years (Hesler et al. 2022). These estimates agreed with earlier predictions and underscored the economic value of spatial roguing, despite added costs relative to the costs of maintaining a healthy vineyard, particularly when considering a scenario of no intervention, for which $10,000 to $15,750 losses per acre were calculated over a 25-year lifespan of a ‘Cabernet franc’ vineyard in New York (Atallah et al. 2012). The cost/benefit analysis of roguing may need to be evaluated by individual vineyard owners who are willing to adopt this leafroll disease management strategy. Critical to the success of roguing is the health status of the replants. Replants should be sourced from nursery vine stocks (scions and rootstocks) that have been extensively tested for viruses, including leafroll viruses, and shown to be clean (Bolton 2020).

In the future, it would be interesting to test the effectiveness of spatial roguing in California vineyards where mealybug population densities are consistently higher than in New York

May 2023 17
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Fruits of a ‘Cabernet franc’ vine infected with GLRaV-3.

vineyards. Similarly, it would be interesting to compare the efficacy of spatial and nonspatial roguing approaches as a response to leafroll disease management. Of equal interest would be a study to test whether a sequential roguing strategy based first, for instance, on spatial roguing to drastically reduce sources of virus inoculum, and then on nonspatial roguing to limit secondary spread would be of value. If carried out in different vineyards with distinct disease prevalence, rate of spread and mealybug species and abundance, such research would inform the best approach for leafroll disease management both from a biological and economical perspective.

A six-year experiment in a commercial ‘Cabernet franc’ vineyard with low disease prevalence and low-density grape mealybug populations in New York showed that spatial roguing and the combination of spatial roguing and insecticides significantly reduced the percentage of infected vines. By comparison, virus incidence among vines in the untreated control vine panels where roguing was not implemented and no insecticides were applied increased from 5% to 16% during the same period. This study was the first to demonstrate the effectiveness of spatial roguing at reducing the incidence of leafroll disease and limiting its spread. It will be interesting to see whether our results on spatial roguing are reproducible in other vineyards of New York, and in vineyards of other grape growing regions of the world, including in California, where many more mealybug species, including the vine mealybug, are of concern and reside at higher populations.


Arnold K, Golino DA and McRoberts N. 2017. A synoptic analysis of the temporal and spatial aspects of grapevine leafroll disease in a historic Napa vineyard and experimental vine blocks. Plant Dis 107:418-426.

Atallah S, Gómez M, Fuchs M and Martinson T. 2012. Economic impact of grapevine leafroll disease on Vitis vinif-

era cv. Cabernet franc in Finger Lakes vineyards of New York. Am J Enol Vitic 63:73-79.

Atallah S, Gómez M, Conrad JM and Nyrop JP. 2015. A plant-level, spatial, bioeconomic model pf plant disease diffusion and control: grapevine leafroll disease. Am J Agri Econ 97:199-218.

Bell VA, Hedderley DI, Pietersen G and Lester PJ. 2018. Vineyard-wide control of grapevine leafroll-associated virus 3 requires an integrated response. J Plant Pathol 100:399-408.

Blaisdell GK, Cooper ML, Kuhn EJ, Taylor KA, Daane KM and Almeida RPP. 2016. Disease progression of vector-mediated Grapevine leafroll-associated virus 3 infection of mature plants under commercial vineyard conditions. Eur J Plant Pathol 146-105-116.

Bolton SL. 2020. What every winegrower should know: viruses. Lodi Winegrape Commission. pp. 138.

Cooper ML, Daugherty MP, Jeske DR, Almeida RPP and Daane KM. 2018. Incidence of grapevine leafroll disease: effects of grape mealybug abundance and pathogen supply. J Econ Ent 111:1542-1550.

Daane KM, Almeida RPP, Bell VA, Walker JTS, Botton M, Falladzadeh M, Mani M, Miano JL, Sforza R, Walton WM and Zaviezo T. 2012. Biology and management of mealybugs in vineyards. In Arthropod Management in Vine-

yards: Pests, Approaches, and Future Directions, N.J. Bostanian, ed. (Springer), pp. 271-307.

Hesler S, Cox R, Loeb G, Bhandari R, Martinson T and Fuchs, M. 2022. Spatial roguing reduces the incidence of leafroll disease and curtails its spread in a ‘Cabernet franc’ vineyard in the Finger Lakes region of New York. Am J Enol Vit 73:227-236.

MacDonald, SL, Schartel TE and Cooper ML. 2021. Exploring grower-sourced data to understand spatiotemporal trends in the occurrence of a vector, Pseudodoccus maritimus (Hemiptera: Pseudococcidae) and improve grapevine leafroll disease management. J

Ricketts KD, Gómez MI, Atallah SS, Fuchs MF, Martinson T, Smith RJ, Verdegaal PS, Cooper ML, Bettiga LJ and Battany MC. 2015. Reducing the economic impact of grapevine leafroll disease in California: identifying optimal management practices. Am J Enol Vit 66:138-147.

Tsai C-T, Chau J, Fernandez L, Bosco D, Daane KM and Almeida RPP. 2008. Transmission of grapevine leafroll-associated virus 3 by the vine mealybug (Planococcus ficus). Phytopathol 98:1093-1098.

Comments about this article? We want to hear from you. Feel free to email us at

18 Grape & Wine Magazine May 2023
A pair of grape mealybugs on the trunk of a ‘Cabernet franc’ vine.

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California is home to some of the most sought-after vineyards in the world, and for good reason. The combination of our unique climate, diverse geography and experienced growers makes it possible to produce world-class grapes that go into exceptional wines.

While the fickle whims of the weather continue to cause challenges, grape growers must also navigate the equally unpredictable terrain of the political climate, where policies and regulations can make or break their livelihoods.

Natural phenomena such as weather events are beyond our control, but the political climate can certainly be influenced through actions and advocacy. With this in mind, the California Association of Winegrape Growers (CAWG) was established in 1974 with the mission to promote the interests of California winegrape growers, giving them a unified voice in the policy-making process. Almost 50 years later, CAWG continues to represent the collective voice of growers at the state, federal and regulatory levels to advocate for policies and practices that support the sustainability and growth of the winegrape industry.

From Passion to Presidency

Growing up surrounded by the vibrant agricultural landscape of the San Joaquin Valley sparked my passion for the industry. Active involvement in organizations like 4-H and FFA further fueled my enthusiasm, leading me to pursue a degree in agricultural business from California State University, Chico and launch a career in agriculture.

In 2015, I joined CAWG as the director of member relations, leading our grower outreach, education and membership efforts. Following a brief period as interim president, I was officially appointed as president of the association in late 2022. I am thrilled to carry on the legacy of robust leadership, working collaboratively with our 27 elected grower board members and exceptional staff. With this shared dedication, CAWG will continue to serve as a powerful advocate for California winegrape growers.

State Sponsored Legislation

The year has kicked off with a flurry of activity as we delve into both state and federal matters. Lawmakers have introduced more than 2,600 bills this year, the highest number in over a decade. While we will take a stance on several bills that affect growers, we are also sponsoring and co-sponsoring the following legislation.

SB 659 – Groundwater Recharge

CAWG is sponsoring SB 659 (Ashby, D-Sacramento). The intent of this bill is to create the statutory framework and a statewide focus on the most impactful solution to address the water management challenges presented by climate change in California.

Unless there is a substantial shift in the approach to water supply, California’s water resources will eventually be depleted. This is an undeniable fact. According to Governor Newsom’s Water Supply Strategy released in August 2022, California is projected to lose around 7.5 million acre-feet

annually by 2040. However, it is worth clarifying that California is not running out of water. Recent storms have demonstrated the immense potential of collecting stormwater for groundwater replenishment. This indicates that we must adopt a new paradigm for water management. This is a critical juncture that necessitates prompt action.

By creating a goal of 10 million acre-feet of new groundwater annually by 2035, SB 659 moves past the

promise of a strategy, and we can begin the real work on groundwater recharge projects that are shovel-ready. By placing this requirement in law, that statutory goal would need to be a consideration in

rulemaking and funding decisions by all state agencies having authority over water.

AB 54 - Research Funding: Winegrape and Smoke Exposure

With the unprecedented losses growers and wineries suffered in 2020 due to wildfire smoke, CAWG and Wine Institute are co-sponsoring AB 54 (Aguiar-Curry, D-Winters). Under this bill, the California Department of Food and Agriculture (CDFA) would allocate funds toward smoke research. These research dollars would facilitate efforts to explore precise way of measuring smoke compounds, methods to mitigate the damage that can occur from exposure to smoke, and methods to prevent smoke damage to winegrapes and wine.

22 Grape & Wine Magazine May 2023

AB 54 would also require CDFA to establish an advisory committee of specified members to provide recommendations for funding research proposals submitted to the department under these provisions. The bill asks the legislature to set aside $5 million in the state budget for this research.

SB 375 – COVID-19 Tax Credit

CAWG is sponsoring SB 375 (Alvarado-Gil, D-Jackson) to provide employers with financial relief from the

cost of compliance with the new COVID-19 workplace safety standards that took effect on February 4.

SB 375 would provide an annual credit against state payroll taxes to reimburse employers for costs such as testing, masking, ventilation systems, exclusion from work and other pandemic-based regulatory compliance costs.

CAWG and our members appreciate the commonsense leadership displayed by Senator Alvarado-Gil in authoring this much-needed legislation. SB 375 will support California employers and growers throughout the state who are still recovering from the pandemic and alleviate the burden put onto employers

for a community-spread virus.

Autonomous Agricultural Equipment

CAWG is leading the push toward amending California regulations to allow for the full utilization of self-driving tractors, robotics and other autonomous farm equipment. This involves industry partners from all aspects of agriculture, academia and manufacturers. Our goal is to increase awareness of the advantages of precision viticulture for the en-

vironment, workforce and growers, and to apply that information and science to cleaning up California law which is based on technology developed 80 years go. That law severely restricts the full utilization of that equipment.

2023 Farm Bill Priorities

The Farm Bill is a comprehensive piece of federal legislation passed every five years by Congress. It covers a wide range of agricultural and rural develop-

May 2023 23
Following a brief period as interim president, Natalie Collins was officially appointed as president of the California Association of Winegrape Growers in late 2022 (all photos courtesy N. Collins.)

ment policies, including crop insurance, commodity programs, conservation, nutrition assistance, research and development, and rural development programs.

CAWG’s priorities in the 2023 Farm Bill include:

Mechanization and Automation Research: CAWG is advocating for the strengthening of research provisions geared towards new technologies, equipment and systems that alleviate concerns with labor availability and vineyard access.

Crop Insurance and Disaster Assistance: The 2020 wildfires dealt a severe blow to growers, underscoring the crucial role of crop insurance. Although there is room for improvement in the program, it remains an essential safeguard against devastating financial losses. CAWG is committed to advocating for ongo-

ing enhancements to the Federal crop insurance program while promoting disaster relief programs.

Pest and Disease Investment: Our growers appreciate the level of support and attention given to the Animal and Plant Health Inspection Service and pest and disease efforts in the previous Farm Bill. The allocated funds have been effective in addressing several critical issues that, without such support, could have had devastating consequences. Going forward, CAWG strongly advocates for continued emphasis on research and development, tools and strategic measures to protect the agricultural industry from invasive pests and diseases.

Wildfire Smoke Research: And finally, there are always new research priorities that arise. It is crucial for the Farm Bill research title to provide access to funding for the industry to address emerging issues like the impact of wildfire smoke

on winegrapes.

CAWG plays a critical role in the success and sustainability of the winegrape industry in California. Through advocacy and education, CAWG helps to ensure that winegrape growers have the support they need to thrive in an ever-changing industry and political climate.

The strength of the association lies in the support it receives from growers and industry partners. Joining CAWG can help you stay informed, connected, and competitive in the dynamic and rapidly changing California winegrape industry. If you are a grower or industry provider looking to improve your business, expand your network, and stay up to date on the latest industry trends, joining CAWG is a wise business investment.

Comments about this article? We want to hear from you. Feel free to email us at

24 Grape & Wine Magazine May 2023
The California Association of Winegrape Growers represent the collective voice of growers at the state, federal and regulatory levels to advocate for policies and practices that support the sustainability and growth of the winegrape industry.


Capturing Maximum Genetic Potential

David Haviland, UCCE entomologist in Kern County, said sugar-feeding ants interrupt vine mealybug control measures, protecting this invasive grapevine pest by killing or intimidating vine mealybug predators and parasitoids that exist in the vineyard.


Sugar-feeding ants are the monkey wrench in a vine mealybug (VMB) integrated pest management program.

Not only does their feeding on honeydew secreted by VMB promote sooty mold on grape clusters, ants know their next meal depends on VMB and actively protect this invasive pest from predator insects and parasitoids that provide biological control and are part of a vineyard integrated pest management program.

Vine mealybugs feed by sucking plant juices. They excrete honeydew which attracts sugar-feeding ants. Since the introduction and spread of VMB in California vineyards, the presence of sugar feeding ants in vineyards has become a much larger issue. Chemical and biological IPM strategies can work in controlling vine mealybug, but when sugar-feeding ants are present, biological control efficacy is impacted.

David Haviland, UCCE entomologist in Kern County, said sugar-feeding ants interrupt VMB control measures, protecting this invasive grapevine pest by killing or intimidating VMB predators and parasitoids that exist in the vineyard. Chemical controls for VMB are a

challenge as this mealybug species has numerous life stages that can be present at the same time. Adults or nymphs or eggs may be killed, but unaffected stages re-populate grapevines. Ants can also help VMB survive by moving them under bark to escape contact insecticides.

Presence of sugar-feeding ants in a vineyard minimizes impact of an inte-

grated pest management plan, Haviland confirmed.

There are different species of ants that cause the same problem for VMB control throughout all grape growing regions of California.

The sugar-feeding invasive Argentine ant is the most prevalent ant species in

26 Grape & Wine Magazine May 2023
Sugar-feeding ants are the monkey wrench in a vine mealybug integrated pest management program (all photos courtesy D. Haviland.)

coastal vineyards. It is about 3 millimeters in length, is uniformly deep brown to black and does not bite or sting. It has one hump between the thorax and abdomen. Worker ants forage during the day. Their populations peak in mid-summer and early fall. Ants nest usually within 2 inches of the soil surface.

In the San Joaquin and Coachella valleys, sugar-feeding native gray ants are most prevalent. These ants are 7.5 millimeters in length and, like the Argentine ant, have one hump. Gray ants nest in the topsoil or under rocks or vineyard debris. They move in an irregular, jerky motion and generally do not travel along trails or sting. Different sub species are found in the San Joaquin and Coachella Valley. The thief ant is the smallest sugar-feeding species and is found primarily in the Coachella Valley.

Other ant species may be found in vineyards, but they are primarily protein feeders.

Control Has Become Harder

Haviland said control of ants in vineyards has become problematic due to loss of the effective chlorpyrifos and increased demand by markets for use of sustainable farming practices. Integrated pest management fills that need, but without ant control is less effective.

Prior to the loss of the organophosphate insecticide Lorsban, it could be used to knock back ant populations in vineyards, Haviland said. An added emphasis on biological control methods in grape production has led growers to encourage native predator populations or to purchase parasitoids to distribute in vineyards.

To preserve the viability of these biological controls, a search began for innovative ant control measures.

Haviland, who spoke about innovations in ant control at the Southern San Joaquin Valley Grape Symposium, said the granular ant baits are more attractive to protein feeding ant species and fail to cut into sugar-feeding ant populations.

Varying environmental conditions in all California grape growing regions also pose difficulty for ant control measures. Liquid baits placed in bait stations are used in vineyards but have not been widely adopted, Haviland said, due to costs. The number of stations needed to be effective and the labor required to maintain them are challenges. High summer temperatures also cause the water portion of the bait to evaporate, and the concentrated bait left is no longer attractive to ants, compared to their diet of VMB honeydew.

Hydrogel Bait as a New Solution

In exploring other options for ant bait delivery, Haviland turned to hydrogels.

There is no shortage of hydrogel definitions in scientific publications, but the easiest to understand is that a hydrogel is mostly a mixture of porous, permeable solids at least 10% by weight or volume of interstitial fluid composed completely or mainly by water. Hydrogels have three-dimensional network structures which can absorb relatively large amounts of fluid (think diapers).

Haviland said sucrose absorbed by hydrogels makes “artificial honeydew.” Very small amounts of pesticide are added to the mix for ant control.

“The amount needed is 100 times lower than is used on foliage for pest control,” Haviland said. The concentration of pesticide is one-tenth of normal use of product. Trials have done applications at rates of 10 gallons of hydrogels per acre, and in some trials, it was effective at 5 gallons per acre.

There are a lot of different types of hydrogels, and Haviland said UC Riverside Entomologist Mark Hoddle’s research found polyacrylamide gels, which have a high level of degradability, are suited for carrying a pesticide mixture.

After hydrogels absorb the sucrose and pesticide mixture, they can be broadcast across a vineyard floor with a broadcast spreader. Haviland explained ants are attracted to this sugar source with a ‘Jello’ consistency that is wet on the outside.

Hydrogels have potential to control sugar-feeding ants in vineyards as the solution requires a fraction of chemical pesticide use compared to foliar applications.

This bait delivery system is experimental, Haviland stressed, but is showing promise in field trials. There is also an example of use of hydrogels to successfully eradicate Argentine ants. At Channel Islands National Park, Argentine ants were threatening populations of native birds. Hydrogel baits were used, and over time, ants were eradicated from Channel Islands.

Haviland said this technology is currently not registered for use as hydrogel delivery is not on any insecticide label. The process to supplement current insecticide labels for use in hydrogel delivery has started, he said. This would involve a 24-C petition to use a pesticide in a different manner than what is noted on the label.

When this ant bait delivery system is approved, Haviland said the window to apply in San Joaquin Valley vineyards would be March 15 to May 1. Honeydew isn’t being produced in large quantities before May, he said. The expected program would be two applications of hydrogels a month apart in valley locations. Timing would be adjusted for coastal or desert areas.

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May 2023 27

Raging Bull Vineyards and Winery: A Unique Blend from the Roots Up Orland Couple Learns the Trade from Scratch to Success

It’s one of only two of its kind nestled in the rolling foothills of Northern Sacramento Valley’s Glenn County. Raging Bull Vineyard and Winery is the home of Charlie Sullivan and Sharon Shipley, who in partnership with Winemaker Bryan Shaw produce grapes and wines from 20 acres of vineyards against a backdrop of the magnificent Mendocino Mountain Range.

Unlike most vineyards and wineries in the Northstate that have a view of the Mendocino range looking eastward, Raging Bull’s view is unique in that it is looking westward to jagged peaks that on any given evening can silhouette a burning sunset catching the clouds on fire.

90 minutes north of Sacramento and a few miles off Interstate 5, Raging Bull offers peace and quiet with nothing else around except a few mooing bovines grazing the grassy knolls.

“Raging Bull Vineyards and Winery is a small, boutique winery,” Shipley says. “Along with our wonderful wines, it’s the perfect spot for your wedding, reunion, anniversary party or just a get-together with friends.”

She is adamant that Sullivan is the mover and she’s the shaker behind Raging Bull, and together the two can make grapes and wine happen.

Raging Bull’s website states, “What started as a blank-canvas land purchase by Charlie has been morphed by their vision and efforts into what it is today.”

However, while it is Sullivan who owns everything, it is Shipley who puts the fine points and details to Raging Bull’s success.

Her contributions are obvious everywhere you go, from the decorations and

stone fire-pit to the custom half-tables in the bar, all done by Shipley, whose previous career was in human resources for 16 years at a copper mine before moving to Northern California. She can be found engaging in all aspects of the winery, from watering, to picking, to crushing,


A few years ago, about 2016, Shipley said, “Charlie decided what we could grow out here west of Orland to have a little extra spending money for retirement.”

A retired well-driller, previous owner of Sullivan Drilling in the Northstate, Sullivan decided to grow grapes to sell to other vineyards.

“And because of numerous other reasons,” Shipley added. “But the main one is that grapes don’t take a lot of water.”

The couple worked the first five acres of

28 Grape & Wine Magazine May 2023
Standing in front of Raging Bull Vineyards and Winery’s 1900 antique wood-carved bar that lends its tasting room a unique, one-of-a-kind atmosphere, is the owner of the Glenn County business, Charlie Sullivan (photo by J.R. Johnson.) Raging Bull Vineyards and Winery produces award-winning wines at the vineyard, tasting room and winery in Orland, Calif. (photo courtesy Raging Bull Vineyards and Winery.)

the vineyard, and by the end of that summer, they had about five acres of vines planted.

“We sure didn’t know a lot about growing grapes and we had to learn mighty fast,” Shipley said. “Thanks to many friends and lots of advice and reading on how to train, water, grow and whatever else we needed to get this crop growing, we got it done.”

A couple years after that first summer’s planting, Sullivan and Shipley had produced their first crop and had to find a way to get them harvested.

“So, we read on how to do that and gathered up all the help we could and got the first harvest completed, that was 2019, we harvested the crop, fermented them and made a 2019 blend wine,” Shipley said.

Not too long after, the couple hired a winemaker, Shaw.

“He told us, ‘Well, you didn’t ruin the

wine,’ and we looked at ourselves and said, ‘Really?’” Shipley added.

“Well, as of today, that blended red wine is our No. 1 selling wine, and it just keeps getting better and better.”

The couple agree they have come a very long way and know much more than they ever thought they would.

“And we just keep learning about something we love to know and learn more about,” Shipley said.

The operation sits on rolling, grassy hills, speckled with old oaks. The tasting room and winery sit next to a large, fish- and croc-infested (fake of course, I hope) pond where guests can paddle around in canoes. The tasting room extends into an outdoor gazebo overlooking the pond with a view of the vineyard and mountain range.

Inside the 4,560-square-foot barn that houses the tasting room and winery

It is the fine points and details at Raging Bull Vineyards and Winery that can be attributed to Sharon Shipley, pictured, whose contributions are obvious everywhere at the facility, from the decorations and stone fire-pit to the custom half-tables in the bar (photo courtesy Raging Bull Vineyards and Winery.)

heralds a beautiful carved wood 1900 antique bar that came from Sacramento. The ornate bar is what gives the room its unique atmosphere along with the Texas longhorns mounted above.

May 2023 29
Contact us to see how we can help! (559)584-7695 or visit us as Serving California since 1983 ContinuedonPage30

“One of only a handful remaining, it’s a beautiful piece of turn-of-the-century craftsmanship unseen in modern building,” Sullivan said.

“This is a perfect place for having a seat and sampling the end result of the production happening all around you,” Shipley said.

With the grapes sitting at the front of the property, Raging Bull boasts an additional 200 acres of land, great for stretching legs, running your dogs, enjoying wildlife and getting a first-hand, up-close view of the vineyard.

Built in 2019, the barn and extended pad behind it serve as most of the grape processing, fermenting and racking space. Two office spaces are on one side and on the other are dual ADA-compliant, four-stall bathrooms. The winery also has three ADA-compliant shower stalls with tiled walls and pebbled floors.

Unique Setting

“We chose to grow grapes in our climate because it is a very consistent climate that is dry,” Shipley said. “The vines tolerate

the heat, volcanic rock soil with hillside drainage, and we have plenty of water.”

Sullivan says the uniqueness of the vineyard is that everything is grown and bottled onsite whereas many wineries nowadays either buy their grapes or wine from other wineries that specifically sell and grow the grapes.

“We are also a vineyard that offers guests to come out and watch our process, help if they choose, watch us bottle or harvest, take a tour around the vineyard in our eight-man golf cart and try the grapes that our wines are made from,” Shipley added.

There is only one other winery in Glenn County, and it sets on the east side of the valley.

Wines and Winemaker

“Prefer certain varietals of wine? This vineyard is sure to have something to your tastes,” Sullivan said. Currently planted are Cabernet, Malbec, Syrah, Sauvignon Blanc, Merlot and Grenache Noir.

“When we have guests, we love to tell the story of how we started this and how our wines have evolved to award-winning wines that have even been featured in Sunset Magazine, The Critics Challenge in San Diego and the San Joaquin Valley Wine Challenge,” Shipley said.

The vineyard and winery feature some of the finest equipment for an operation the size of Raging Bull.

“Our wines are made in the mind of old school technology with the most modern equipment,” Sullivan said. “We use the finest yeast and plant-based additives to make the wines and varieties our customers are sure to enjoy.”

Providing water to the vineyard are two 16-inch agriculture wells along with two domestic wells. All four were drilled by Sullivan, who has been drilling water wells for nearly 40 years.

Winemaker Bryan Shaw started with Raging Bull in June 2021.

He was educated in the viticulture and enology winemaking program at UC Davis and has won multiple silver and gold medal awards for his past vintages of wines at previous wineries.

His knowledge in many winemaking styles and fermentation techniques have been incremental to Raging Bull.

“We chose Bryan Shaw, our winemaker, because he has a variety of expertise, knowledge and education that simply makes a good wine,” Shipley said.

Shaw has worked along some of the best winemakers in the country and is very thorough and focused on how to make an award-winning wine, Sullivan added.

“He loves to chat with the customers and entice them with his knowledge on winemaking and will even go so far as to do barrel tasting with them,” Shipley says.

Sullivan adds that the process of winemaking is up to the winemaker and what he wants to achieve with the grapes.

“We use stainless steel tanks and numerous kinds of oak barrels in our processing,” he said. “We go through a fermenting, destemming and crushing process before the wines get into the barrels and tanks.”

The winery bottles twice a year by appointment with a mobile wine-bottling service as is customary these days.

To date, the winery’s award-winning wines are Syrah, earning three gold medals, 2020 Cabernet Sauvignon with three silver medals and 2020 Merlot with one bronze.

Comments about this article? We want to hear from you. Feel free to email us at

30 Grape & Wine Magazine May 2023
Raging Bull Vineyards and Winery is located in Glenn County a few miles west of Interstate 5 and is surrounded by rolling, grassy hills with a backdrop of the Mendocino Mountain Range (photo by J.R. Johnson.) Winemaker Bryan Shaw started with Raging Bull in June 2021. He was educated in the viticulture and enology winemaking program at UC Davis and has won multiple silver and gold medal awards for his past vintages of wines at previous wineries (photo by J.R. Johnson.)
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Know Your Enemy

The Importance of Modern Research in the Grapevine Trunk Diseases Context

SAMUELE MORETTI |Ph.D., Laboratoire Vigne, Biotechnologieset Environnement, Université de Haute-Alsace, Colmar, France

CHRISTOPHE BERTSCH |Professor, Laboratoire Vigne, Biotechnologieset Environnement, Université de Haute-Alsace, Colmar, France and SIBYLLE FARINE |Ph.D., Laboratoire Vigne, Biotechnologieset Environnement, Université de Haute-Alsace, Colmar, France

There are historical sources describing at least one trunk disease in grapevine in ancient Roman and Greek civilizations as well as in the Mediterranean Middle Ages, with some authors suggesting that it may be as old as viticulture itself (Mugnai et al. 1999). Nowadays, Grapevine trunk diseases (GTDs) are present in every grapevine-growing country. This designation refers to a group of wood diseases that affect the woody structures of grapevine plants, causing different symptoms in wood, leaves, twigs and berries, and eventually sudden or progressive decline of the affected plants, therefore reducing drastically the life of a vineyard (Bertsch et al. 2013; Kenfaoui et al. 2022). Their impacts are significant on many levels; they damage the viticultural landscape, cause reduction in grape yield, wine production and quality, and have a significant impact on the wine market and winegrowing economies generally. Particularly over the last two decades, GTDs’ incidence rose to alarming levels in most grapevine growing regions (especially in the Mediterranean basin), rendering a large percentage of affected vineyards unproductive (Guérin-Dubrana et al., 2019). In countries where the wine market is extremely important like France, loss in production is estimated at around a billion U.S. dollars per year, and numbers from California and Australia are on the order of millions and billions of dollars per year, respectively (Siebert 2001)(Fontaine et al. 2016). Learning to combat them more effectively is essential.

Solutions for Combatting GTDs

Various curative and preventative solutions have been proposed over the course of time. Early strategies likely consisted of simply removing the affected plants. The twentieth century saw the widespread use of chemical pesticides like sodium arsenite against the Esca complex of diseases. While effective, over the last 30 years, most chemicals have been banned for environmental and toxicity concerns. Physical interventions, such as trunk renewal, trunk surgery (curettage) and good pruning techniques, are the most efficient, while the use of biocontrol agents has also proven effective to an extent (Mondello et al. 2018; Pacetti et al. 2021; SICAVAC 2022). However, for several reasons, some of these techniques are not always viable either financially or practically. There is a clear need for alternative sustainable and environmentally friendly strategies.

In the quest for alternative solutions, fundamental research on the pathogens and their mechanisms of action and interaction with grapevine plants is crucial. Indeed, these diseases are mostly associated with fungal pathogens, entering the plants mainly through pruning wounds, causing lesions and necrosis formation in wood as well as unique leaf symptom patterns.

The Esca Complex of Diseases

The Esca complex remains one of the most catastrophic GTDs, nowadays regrouping four different syndromes: Petri disease, brown wood streaking, grapevine leaf stripe disease (GLSD) and white rot (Surico 2009). The fungi behind each disease belong to two different groups: Ascomycetes and Basidiomycetes fungi (the two ascomycetes historically associated with the complex of diseases are Phaeomoniella chlamydospora (Pch) (Crows and Grams 2000) and Phaeoacremonium minimum (Pmin) (Gramaje et al. 2015.)) They cause multiple types of necrosis in the trunk of the vines while also often leading to “tiger stripe leaves”, the foliar manifestation of GLSD (Figures 1 and 2, see page 32 and 33).

32 Grape & Wine Magazine May 2023
Figure 1. Images of wood necrosis retrieved in grapevine plants affected by the Esca complex of diseases.In the upper left image, brown wood streaking is shown; in the upper right, a mix of types of wood necrosis; and in the lower image, detail of the white rot syndrome is shown (top left and right photos by C. Bertsch, bottom photo by S. Moretti.)

The main fungus responsible for the white rot syndrome is usually a Basidiomycete fungus, most often a Fomitiporia species, that usually varies according to geographical region (Fischer 2006). In Europe, Fomitiporia mediterranea (Fmed ) (Fischer 2002) is the main fungus responsible for white rot. The syndrome causes the complete degradation of the wood attacked, reducing it to a spongy-yellowish residue, therefore irreversibly compromising the physical structure of the plants and the water transport. In old vineyards, the situation in which both white rot and GLSD are present is more often observed, raising a series of question marks on possible links between Fomitiporia species and the tiger stripe leaf patterns, historically associated with Ascomycetes fungi species (these two diseases manifesting together are sometimes referred to as ‘Esca proper’ (Surico 2009.) Considering all these interactions, it is easy to understand the devastating impact caused by this complex of diseases.

Mechanisms of Action

Understanding the mechanisms behind the pathogens’ activity in the Esca complex is crucial for predicting their behavior, and preventing or counteracting the damage they can cause. Past research efforts in this context have mostly focused on two main fronts: firstly, attempts to identify compounds (either released by the fungi or by the degrading wood) possibly responsible for the typical foliar symptoms, potentially being transported to the vines’ leaves via the sap (never fully demonstrated); and secondly, the study of wood necrosis and lesions formation and wood degradation, the latter mainly attributed to enzymes secreted by the fungi to decompose lignin and cellulose, the main wood constituents (Sparapano et al. 2001; Claverie et al. 2020; Pacetti et al. 2022). Moreover, most likely because of the historical conviction that Basidiomycetes species can only arrive once the terrain has been prepared by other fungi, research has mostly focused on Ascomycetes fungi, leaving the role of Basidiomycetes species quite unexplored in the Esca complex. However, a recent observation coming from trunk surgery confirmed what some researchers had suspected: the complete removal of white rot drastically reduced the foliar symptoms (Pacetti et al.

2021; Lecomte et al. 2022). This suggests that Basidiomycetes (such as Fmed ) are not mere secondary pathogens degrading wood but might actually have a larger role in the Esca complex of diseases, fueling interest in studying their role in the disease, recently highlighted by other researchers (Brown et al. 2020).

Recent Research on Fomitiporia mediterranea

In our laboratory, we made Fmed a main research topic, taking innovative approaches to study the pathogenesis mechanisms of the fungus in collaboration with two other research groups, one led by Laura Mugnai (University of Florence, Italy) and the other led by Barry Goodell (University of Massachusetts, USA), world-renowned experts in Esca complex and wood decay mechanisms, respectively. Fungal wood degradation has always been theorized in the framework of a binary division between white rot in which the main process involves enzymes, and brown rot in which the main process involves chemical compounds and their interaction with iron present in

the wood cells, generating free radicals (a non-enzymatic process) (Blanchette 1991; Goodell 2020).

Our approach was motivated in large part by recent genomic studies calling into question the white rot versus brown rot paradigm (Riley et al. 2014). We analyzed the possibility for Fmed, a white rot fungus, to adopt a series of chemical reactions of a non-enzymatic nature that ultimately produces free radicals (namely hydroxyl radicals) to start wood degradation. It is in fact well demonstrated that in intact wood cell walls, micropores are too small to allow enzymes to pass through and digest wood (Flournoy et al. 1991; Kleman-Leyer et al. 1992). These mechanisms have been recently proven possible for the other two Ascomycetes fungi involved in the Esca complex as well as for Eutypa lata, mainly involved in Eutypa dieback, another GTD (Perez-Gonzalez et al. 2022). Our in vitro research demonstrates that the non-enzy-

May 2023 33
Figure 2. A series of foliar and canopy symptoms of grapevine plants affected by the Esca complex of diseases. On the upper left and right images, the typical “tiger stripe leaf” symptoms can be seen. In the lower image, plant apoplexy is shown (photos by C. Bertsch.)

matic mechanisms producing free radicals are possible for Fmed too (Moretti et al. 2023), further confirming that decay mechanisms can be much more nuanced than a reductive binary classification while also offering new possibilities for disease control.

Future Perspectives

Indeed, what may seem a mere technical distinction does in fact have significant implications for real-world applications. Understanding that every main fungus involved in the Esca complex can employ some non-enzymatic mechanisms to produce free radicals immediately points to a possible new research approach to controlling and fighting the disease: antioxidants and chelators, which are substances that bind free radicals and iron, respectively. Targeted use of antioxidants and/or iron chelator could therefore in theory reduce this non-enzymatic degradation process, by rendering free radicals inactive or iron unavailable for the non-enzymatic processes. In vitro results on other GTD fungi are encouraging as it appears that free radical production is reduced or completely blocked in the presence of antioxidants/chelators (Sebestyen et al. 2022). Their impact on free radical production by Fmed needs to be tested with research conducted in plants and in the field that tests various application methods for any resulting reduction in wood necrosis and degradation. If antioxidants/chelators prove to be an effective potential way to control symptoms of the Esca complex, research should identify sustainable and environmentally friendly sources. This research approach could also be extended to other GTDs and respective pathogens.


Bertsch, C., Ramírez-Suero, M., Magnin-Robert, M., Larignon, P., Chong, J., Abou-Mansour, E., Spagnolo, A., Clément, C., Fontaine, F. (2013). Grapevine trunk diseases: Complex and still poorly understood. Plant Pathol. 62, 243–265. doi:10.1111/j.1365-3059.2012.02674.x.

Blanchette, R. A. (1991). Delignification by wood-decay fungi. Annu. Rev. Phytopathol. 29, 381–398. doi:10.1146/annurev. py.29.090191.002121.

Brown, A. A. A., Lawrence, D. P. P., Baumgartner, K. (2020). Role of basidiomycete fungi in the grapevine trunk disease esca. Plant Pathol. 69, 205–220. doi: 10.1111/ppa.13116.

Claverie, M., Notaro, M., Fontaine, F., Wéry, J. (2020). Current knowledge on Grapevine Trunk Diseases with complex etiology: a systemic approach. Phytopathol. Mediterr. 59, 29–53. doi:10.14601/Phyto-11150.

Crous, P. W., Gams, W. (2000). Phaeomoniella chlamydospora gen. et comb. nov., a causal organism of Petri grapevine decline and esca. Phytopathol. Mediterr. 39, 112–118. doi:10.14601/Phytopathol_Mediterr-1530.

Fischer, M. (2002). A new wood-decaying basidiomycete species associated with esca of grapevine: Fomitiporia mediterranea (Hymenochaetales). Mycol. Prog. 1, 315–324. doi:10.1007/s11557-006-0029-4.

Fischer, M. (2006). Biodiversity and geographic distribution of basidiomycetes causing esca-associated white rot in grapevine: A worldwide perspective. Phytopathol. Mediterr. 45, 30–42. doi:10.14601/Phytopathol_Mediterr-1846.

Flournoy, D.S., Kirk, T.K., Highley, T.L. (1991). Wood decay by brown-rot fungi: changes in pore structure and cell wall volume. Holzforschung 45, 383–388. doi:10.1515/hfsg.1991.45.5.383.

Fontaine, F., Gramaje, D., Armengol, J., Smart, R., Nagy, Z.A., Borgo, M., Rego, C.,Corio-Costet, M.F. Grapevine Trunk Diseases A Review. OIV Publications: Paris, France, 2016; p. 25. Goodell, B. (2020). Fungi Involved in the Biodeterioration and Bioconversion of Lignocellulose Substrates. In The Mycota.(A Comprehensive Treatise on Fungi as Experimental Systems for Basic and Applied Research) vol 2. Genetics and Biotechnology; Benz, J.P., Schip-827 per, K., Eds.; Springer Cham: Switzerland; Vol. 2, pp. 369–397, doi: 10.1007/978-3030-49924-2_15.

Gramaje, D., Mostert, L., Groenewald, J. Z., Crous, P. W. (2015). Phaeoacremonium: From esca disease to phaeohyphomycosis. Fungal Biol. 119, 759–783. doi:10.1016/j.funbio.2015.06.004.

Guérin-Dubrana, L., Fontaine, F., Mugnai, L. (2019). Grapevine trunk disease in European and Mediterranean vineyards: occurrence, distribution and associated disease-affecting cultural factors. Phytopathol. Mediterr. 58, 49–71. doi:10.14601/ Phytopathol_Mediterr-25153.

Kenfaoui, J., Radouane, N., Mennani, M., Tahiri, A., El Ghadraoui, L., Belabess, Z., Fontaine, F., El Hamss, H., Amiri, S., Lahlali, R., Barka EA.(2022). A Panoramic View on Grapevine Trunk Diseases Threats: Case of Eutypa Dieback, Botryosphaeria Dieback, and Esca Disease. J. Fungi, 8, 595. doi: 10.3390/jof8060595.

Kleman-Leyer K., Agosin E., Conner A.H., Kirk T.K. (1992) Changes in molecular size distribution of cellulose during attack by white rot and brown rot fungi. Appl. Environ. Microbiol 58,1266–1270. doi: 10.1128/aem.58.4.1266-1270.1992.

Lecomte, C., Cholet, C., Bruez, E., Martignon, T., Giudici, M., Simonit, M., Alonso Ugaglia, A., Forget, D., Miramon, J., Arroyo, M., Dubourdieu, D., Geny-Denis, L., Rey, P. (2022). Recovery after curettage of grapevines with esca leaf symptoms. Phytopathol. Mediterr. 61, 473-488. doi: 10.36253/ phyto-13357.

Mondello, V., Songy, A., Battiston, E., Pinto, C., Coppin, C., Trotel-Aziz, P., Clément, C., Mugnai, L., Fontaine, F. (2018). Grapevine trunk diseases: A review of fifteen years of trials for their control with chemicals and biocontrol agents. Plant Dis. 102, 1189–1217. doi:10.1094/PDIS-08-17-1181-FE.

Moretti, S., Goddard, M.-L., Puca, A., Lalevée, J., Di Marco, S., Mugnai, L., Gelhaye, E., Goodell, B., Bertsch, C., Farine, S. (2023). First Description of Non-Enzymatic Radical-Generating Mechanisms Adopted by Fomitiporia mediterranea: An Unexplored Pathway of the White Rot Agent of the Esca Complex of Diseases. J. Fungi 9, 498. jof9040498

Mugnai, L., Graniti, A., Surico, G. (1999). Esca (black measles) and brown wood-streaking: two old and elusive diseases of grapevines. Plant Dis. 83, 404–418. doi: 10.1094/ PDIS.1999.83.5.404

Pacetti, A., Moretti, S., Pinto, C., Compant, S., Farine, S., Bertsch, C., Mugnai, L. (2021). Trunk Surgery as a Tool to Reduce Foliar Symptoms in Diseases of the Esca Complex and Its Influence on Vine Wood Microbiota. J. Fungi 7, 1–26. doi: jof7070521.

Pacetti, A., Moretti, S., Perrin, C., Gelhaye, E., Bieler, E., Kassemeyer, H.-H., Mugnai, L., Farine, S., Bertsch, C. (2022). Grapevine Wood Degrading Activity of Fomitiporia mediterranea M. Fisch.: A Focus on the Enzymatic Pathway Regulation. Front. Microbiol. 804, 13, 844264, doi:10.3389/ fmicb.2022.844264.

Perez-Gonzalez, G., Sebestyen, D., Petit, E., Jellison, J., Mugnai, L., Gelhaye, E., Lee, N., Farine, S., Bertsch, C., Goodell, B. (2022) Oxygen Radical-Generating Metabolites Secreted by Eutypa and Esca Fungal Consortia: Understanding the Mechanisms Behind Grapevine Wood Deterioration and Pathogenesis. Front. Plant Sci. 13:921961. doi: 10.3389/ fpls.2022.921961

Riley, R., Salamov, A. A., Brown, D. W., Nagy, L. G., Floudas, D., Held, B. W., Levasseur, A., Lombardf V., Morin, E., Otillar, R., Lindquist, E. A., Sun, H., LaButti, K. M., Schmutz, J., Jabbour, D., Luo, H., Baker, S. E., Pisabarro, A. G., Walton, J. D., Blanchette, R. A., Henrissat, B., Martin, F., Cullen, D., Hibbett, D. S., Grigoriev, I. V. (2014). Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/ brown-rot paradigm for wood decay fungi. Proc. Natl. Acad. Sci. 111, 9923–9928. doi:10.1073/pnas.1400592111.

Sebestyen, D., Perez-Gonzalez, G., Goodell, B. (2022). Antioxidants and iron chelators inhibit oxygen radical generation in fungal cultures of plant pathogenic fungi. Fungal Biol. 126: 480-487. doi: 10.1016/j.funbio.2022.04.002.

SICAVAC, (2022). Bonnes Pratiques de Taille et Techniques Curatives Contre les Maladies du Bois, SICAVAC & B.IV.C., Imprimerie Paquereau, Angers, France, 138 pp. ISBN 978-29584692-0-7.

Sparapano, L., Bruno, G., Graniti, A. (2001). Three year observation of grapevines cross-inoculated with esca associated fungi. Phytopathol. Mediterr. 40, S376–S386. doi: 10.14601/ Phytopathol_Mediterr-1643

Surico, G. (2009). Towards a redefinition of the diseases within the esca complex of grapevine. Phytopathol. Mediterr. 48, 5–10. doi:10.14601/Phytopathol_Mediterr-2870.

Siebert, J.B. (2001). Eutypa: The economic toll on vineyards.

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