Pierce's disease is caused by Xylella fastidiosa bacteria, which can be spread by a variety of sharpshooter insects. The outbreak in Napa and Sonoma counties is associated with blue-green sharpshooters.
There's been a “huge increase in traditional (Pierce's disease) hotspots and in sites not normally affected,” said Rhonda Smith, UC ANR Cooperative Extension viticulture advisor in Sonoma County. Smith said the worst problems seem to be in areas with the warmest winters. The Russian River Valley and Dry Creek areas have been the hardest hit.
In Napa County, a similar patchwork of vineyards were impacted by Pierce's disease last year, said Monica Cooper, the UC ANR CE viticulture advisor in Napa County. She said there has been a "marked increase" in areas where the disease is normally seen. In areas along riverbanks where habitat restoration has taken place, the problem is diminished. In the past, non-native plants along riverbanks have acted as reservoirs for X. fastidiosa, keeping the bacteria in the area even after infected vines have been destroyed.
UC ANR CE advisor at the Central Coast, Larry Bettiga, said the area hasn't seen a corresponding increase in Pierce's disease.
"The more lush river system in Napa and Sonoma counties has plenty of areas to serve as reservoirs for both the bacteria that causes Pierce's and its vectors," Bettiga said. “We don't have blue-green sharpshooters in Monterey County.
For more information on Pierce's disease, see the UC Integrated Pest Management page on the topic.
The lengthy article was written in honor of UC Cooperative Extension's 100th anniversary. The organization was formed on May 8, 1914, when President Woodrow Wilson signed the Smith-Lever Act into law.
For the story, Franson interviewed Barbara Allen-Diaz, vice president of UC Agriculture and Natural Resources, and several UCCE advisors who work in Northern California viticulture. Allen-Diaz noted agriculture's wide scope in the Golden State.
“We farm 400 commodities in California with a value of $45 billion,” Allen-Diaz said. UC Ag and Natural Resources focuses on healthy food systems, healthy environments, healthy communities and healthy Californians.
Rhonda Smith, a UCCE advisor in Sonoma County, said she has seen many changes since she started in 1986.
"In early days, most growers were small, independent farmers," Now most of the people Smith works with are employees of large corporations, many multinational.
In the early days, farm advisors dealt with multiple crops, and the viticultural work and research was primarily focused on improving the culture of vines. Things soon changed. “Increasingly, the trials were associated with grapevine pests, especially exotic pests,” Smith said.
Monica Cooper, UCCE viticulture advisor since April 2009, walked into a big problem when she took her job: the European grapevine moth. She also conducts research with mealybugs and leafroll virus and believes red botch virus and water issues to be important concerns for winegrape growers in the near future.
Glenn McGourty, UCCE advisor in Mendocino County, agrees.
“I’ve been telling growers that they need to learn to farm without irrigation,” McGourty said.
“We recognize that the current population of farmers is aging, and that we need to get our younger farmers prepared and ranching,” said Stephanie Larson, UC Cooperative Extension advisor in Sonoma County and director of the new training program. “We’re really hoping to not only get more farmers and ranchers trained, but to increase food access and food production in Sonoma County, and also to teach more people about where their food comes from.”
Students in the program will split their time between classwork with ag teachers, field work with local farmers and business plan development with small business experts. The program will expand to include the broader farming community, connecting students with restaurants and grocers that buy local produce and the slew of farmers’ markets around the county.
“Programs like this strengthen the parts we already have and bring farmers together,” Larson said. “We used to work mainly in silos, but we’ve been breaking those silos down, and finding it works much better together than separately.”
Another blessing for Napa
Paul Franson, Napa Valley Register
On top of wine, food, arts and culture that some large cities might envy, Napa Valley has an invaluable, little-recognized asset: an uncommonly cooperative and educated wine industry.
Responding to Napa County's higher-than-average interest in healthy foods, sustainable principles and wellness lifestyle, the board of supervisors last year created a Local Food Advisory Council. Now the council is looking for citizen input to pursue new initiatives, according to a blog on the Napa County Register website.
Monica Cooper, director of the Napa County University of California Cooperative Extension, is an ex-officio member of the council. Cooper is the county’s viticulture farm advisor and a big champion of expanding local food production, according to a previous article in the newspaper.
“It’s important to have more crop diversity,” Cooper was quoted in the story, and she sees that in small plots, not wide swaths of the county.
Napa's Local Food Advisory Council has identified three priority areas and is seeking volunteers to serve on subcommittees for:
- Education and Outreach: Help design communications networks to encourage public involvement and information sharing, such as advocacy programs, printed materials, events, website, social media, etc.
- Local Food Production and Distribution: Help develop mutually beneficial food supply systems linking local farmers to community kitchens, markets and residents;
- Food Policy: Help influence and communicate county rules, regulations and fees for growing, selling and/or donating food products by both home and commercial producers.
Cooper took the post two years ago, following the untimely death of her predecessor Ed Weber.
“Monica could not have arrived at a more important time for Napa’s winegrape industry,” the story quoted Jennifer Putnam, executive director of the Napa Valley Grapegrowers Association. “We were incredibly fortunate to have such an accomplished entomologist in the role just as the European grapevine moth infestation was being discovered. She, along with our ag commissioner and others, quickly developed and acted on a plan to control the spread of this devastating pest. Her sense of urgency and expertise were critical in our ability to get a handle on that outbreak.”
Cooper has a doctorate degree in plant medicine from the University of Florida, where she also studied entomology, plant pathology, weed and soil science, agronomy and horticulture, the article said.
“I think Monica has (been) a tremendous asset for the valley,” Whitmer was quoted. “I feel bad that right out of the gate she had to deal with the European grapevine month, but she’s been a tremendous help in providing the science to help fight it.”
A former Peace Corps volunteer, Cooper got her start at UC in the Berkeley laboratory of biological control specialist Kent Daane.
Cooper told reporter Paul Franson she is happy with her job in Napa.
"I love working in an agricultural county,” Cooper was quoted. “The variety of work is most interesting, too. You never know what will happen and I could never sit in an office all day. I love working with growers. They’re always thirsty for information.”