Growers are all too familiar with the significant threat posed to vineyards by Pierce’s Disease (PD)
SACRAMENTO — This week, Assemblywoman Dawn Addis, (D-Morro Bay) introduced AB 1861 to extend a vital program within the California Department of Food and Agriculture (CDFA) that protects California’s picturesque vineyards and our iconic wine industry from deadly disease. This legislation is sponsored by the California Association of Winegrape Growers and Wine Institute.
“The wine industry is integral to the economic success of the Central Coast and all of California,” said Addis. “I’m proud to author AB 1861 that extends a crucial line of defense for our wine industry against invasive disease. We have a track record of collaboration among State, local, federal government and the industry itself when it comes to battling Pierce’s Disease and the Glassy Winged Sharp Shooter. I’m proud to extend this collaboration and to be part of the on-going success of California’s wine regions.”
“Over the last 23 years, the Pierce’s Disease Control Program has been fundamental in addressing the challenges posed by Pierce’s Disease and other pests and diseases,” said Natalie Collins, President of the California Association of Winegrape Growers. “We thank Assemblymember Addis for her leadership in authoring this important legislation.”
“Our collaboration with California’s Department of Food and Agriculture continues to protect our vineyards against Pierce’s Disease and the Glassy-Winged Sharpshooter,” said Robert P. Koch, President and CEO of Wine Institute. “AB 1861 will extend critical research, innovation, and mitigation and prevention efforts to safeguard the health and vitality of our winegrapes against this invasive species. We are grateful for the support of Assemblymember Addis and the California legislature.”
California’s wine industry stands as a formidable economic force, contributing significantly to the state’s prosperity. California leads the nation in wine production, producing 80 percent of all U.S. wine and generating a staggering $170.5 billion in annual economic activity. With 615,000 acres of winegrapes producing 3.6 million tons, California’s commitment to sustainability shines through, with eighty percent of its wine produced in certified sustainable wineries.
Growers are all too familiar with the significant threat posed to vineyards by Pierce’s Disease (PD), carried between plants by an insect called the glassy-winged sharpshooter (GWSS). Since the 1990s, GWSS has been one of the most invasive and deadly pests for vineyards. When a vine develops PD, its ability to draw in moisture is hindered and the plant will either die or become unproductive. PD has caused millions of dollars in damage throughout the state.
To safeguard California’s wine industry and support ongoing research, inspection, and control measures for PD, AB 1861 will extend the Pierce’s Disease Control Program (program) and the PD/GWSS Board from 2026 to 2031. This extension is subject to approval of growers through a referendum that would be conducted in 2025. The last PD/GWSS referendum, conducted in 2020, passed with 78 percent approval of California winegrape growers.
California’s first indication of a severe threat posed by this disease occurred in Temecula in August of 1999, when more than 300 acres of vineyards were infected with PD and had to be destroyed. In response, the Legislature enacted a legislative package that year creating the advisory task force. In 2001, the program was created to fight the spread and find solutions for PD and GWSS.
The program has demonstrated success in controlling the spread of PD and GWSS due to the collaborative efforts involving federal, state, and local agencies, along with grower-funded research. The program is funded through a combination of federal and industry funds, as well as grape grower assessments. These assessment funds are used for research, outreach, and related activities on PD, GWSS, and other designated pests and diseases of winegrapes.
The research overseen by the PD/GWSS Board is critical to advancing knowledge, improving practices, and guaranteeing the longevity of the California winegrape industry. The focus of current research projects ranges from investigating pests and diseases to evaluating existing control methods to exploring new promising control strategies.