PD/GWSS Assessment & Referendum

Pierce's Disease and Glassy-Winged Sharpshooter Assessment

Over 49.5 Million for Research Since 2001

In 2001, an annual, value-based assessment on winegrapes was established to fund PD/GWSS research and related activities. The PD/GWSS Board was also established at that time. The Board advises the California Department of Food and Agriculture on the best use of assessment funds, ensuring dollars are spent wisely and productively to find solutions to PD, GWSS, and other designated pests and diseases of winegrapes.

The Board has invested over $57.7 million since 2001 on research and outreach. The Board sets the annual assessment rate, with a maximum of $3.00 per $1,000 of value. The annual assessment rate has averaged $1.34 per $1,000 of value and remains steady at $1.25 for the 2024 harvest, for the third year in a row.

PD/GWSS Referendum Scheduled for Spring 2025

The PD/GWSS Referendum is conducted every five years by law, and will take place again in Spring 2025. Last conducted in 2020, the referendum passed with 78 percent approval of California winegrape growers, extending the PD/GWSS assessment through 2026.

Through the renewal of the assessment, growers’ continued commitment to the industry and government partnership, led by the statewide Pierce’s Disease Control Program, leverages funding for essential activities, including:

  • Research
  • Maintaining and monitoring GWSS traps
  • Conducting nursery stock shipment inspections
  • Overseeing nursery stock treatments
  • Controlling GWSS using area-wide management programs
  • Operating a biological control program to suppress GWSS populations

Voter Eligibility and Timeline

To establish the list of eligible grower voters for the 2025 vote, CDFA will request all wineries and winegrape processors to submit the names, mailing addresses, and assessment values of all producers who paid the assessment on grapes crushed during the 2024 harvest. Every entity that produced winegrapes in 2024 will receive a ballot in March or April 2025. Growers who operate multiple entities will receive a separate ballot for each entity. Each ballot should be voted and returned.

Passage Requirements

At least 40 percent of the eligible voting entities must cast ballots for the referendum to be valid. Passage of the referendum requires either:

  1. Of those who vote, 65 percent vote “yes,” and the “yes” voters must have paid the majority of the assessment that was paid by those who voted;
  2. Of those who vote, a majority vote “yes,” and the “yes” voters must have paid 65 percent or more of the assessment that was paid by those who voted.