Lodi Grape Day originated in 1952 and was created by a Lodi Chamber of Commerce Agribusiness Chairman, Calvin Mettler, and UC Davis Extension agent Gordon F. Mitchell to provide the latest information and thinking around grape culture to harvest.

Lodi Grape Day topics vary from year to year. In previous years, topics have included:

        • Integrated pest and disease management
        • New technologies and mechanization
        • Weed management
        • Nutrient and water management
        • Market information

This year’s Lodi Grape Day was held on Tuesday, February 2nd, and the University of California Cooperative Extension (UCCE) and The Lodi Chamber of Commerce’s Agribusiness Committee hosted this event for the first time virtually.

A video recording of all presentations is now available along with closed captioning. To turn on closed captioning: once the video is open, you will see at the bottom of the video on the right-hand side that there are tools you can select. Select the second icon that says CC. To watch the video, click below:


The day was wonderful with a packed agenda and a fantastic lineup of speakers. The agenda included a nice mix of viticulture and enology topics, as follows:

          • Glassy-winged Sharpshooter Area-wide Programs in the San Joaquin Valley, Beth Stone-Smith, PhD, California Assistant State Plant Health Director, USDA APHIS PPQ
          • The Vineyard of the Present and the Future, S. Kaan Kurtural, PhD, Associate Specialist in Cooperative Extension in Viticulture, UC Davis
          • Aspects of Vineyard Weed Management, Anil Shrestha, PhD, Professor of Weed Science, Fresno State University
          • Grape Smoke Exposure Risk and Mitigation, Anita Oberholster, PhD, Associate Specialist in Cooperative Extension in Enology, UC Davis
          • LWC Viticulture Research, IPM Updates, and Closing Remarks, Stephanie Bolton, PhD, Research & Education Director, Lodi Winegrape Commission

Rebecca Towell, the current Lodi Chamber of Commerce Agribusiness Committee Chair, welcomed everyone to Lodi Grape Day. She thanked all the individuals in the Agribusiness Committee who were responsible for organizing the event. The Committee includes Dr. Stephanie L. Bolton with the Lodi Winegrape Commission (LWC), Bree Hunt with Constellation, Jerry and Bruce Fry with Mohr-Fry Ranches, Joe Valente with Kautz Farms, Sarah Meidinger with Bank of Stockton, Mickey Nuss with F&M Bank, Amy Blagg with Lodi District Grape Growers Association (LDDGA), and Larry Whitted, a local PCA and the LWC Research, Education, and Communication Committee Chair.

Dr. Kari Arnold, the Stanislaus Country Farm Advisor for the University of California Cooperative Extension (UCCE), moderated the beginning of the session. She covers many crops such as grapes, walnuts, apricots, and cherries. Dr. Arnold introduced the first speaker, Beth Stone-Smith, PhD.

Beth Stone-Smith works with the United States Department of Agriculture (USDA) and focuses on the glassy-wing sharpshooter and Pierce’s Disease. She discussed the statewide program, Pierce’s Disease Control Program, and how as a community we can help. This program was formed at the state level by the California Department of Food and Agriculture (CDFA), receives funding every year from the USDA, and works with counties and the industry. The program’s main goal is to try and reduce Pierce’s Disease in California and to try and contain the glassy-winged sharpshooter. One component of the Pierce’s Disease Control Program that Beth focused on was the area-wide initiatives. The focus of these programs is to suppress the glassy-winged sharpshooter over large agricultural areas, targeting overwintering crops such as citrus, buy time for research, and ultimately slowing the spread. Beth hit home when she mentioned that as a community we need to stay vigilant, informed, and engaged.

The next speaker of Lodi Grape Day, Dr. Kaan Kurtural with UC Davis, then began his presentation on the vineyard of the present and future. He began by explaining that for a grower, business is changing rapidly. A willing labor force is decreasing while the cost of labor is increasing. Also, land availability and costs have increased, and in regards to water, access to water has become a problem since SGMA has come into play. He discussed the evolution of the vineyard and other advances to the mechanization of vineyards and vineyard management. Dr. Kurtural concluded that mechanical pruning, mechanized canopy management, and mechanized harvesting will be common. Repetitive tasks will also most likely move to co-robots and unmanned vehicles; examples include spraying and tillage. Finally, sensor-driven decision-making for water status, irrigation design, and irrigation delivery will also become more commonplace in the vineyard of the future.

Dr. Kamyar Aram, the UCCE East Bay Specialty Crops Advisor, moderated the second half of the agenda. Along with most crops, he covers many areas such as plant production, plant protection, endemic and invasive pests and diseases, water quality, quantity, and security, and sustainable food systems. Dr. Kamyar Aram introduced the third speaker, Dr. Anil Shrestha.

Dr. Anil Shrestha with Fresno State began his presentation by highlighting different aspects of vineyard weed management. He first discussed the introductory basics of issues with weeds. Then, he explained that weeds are hosts for diseases and pests. Integrated Weed Management was first discussed in 1981 and continues today. Dr. Shresthra explained why the need for the discussion exists: because of herbicide resistance. There are currently 515 resistant biotypes and 263 species (152 dicots and 111 monocots) that are resistant to at least one herbicide. There is no new mode of action – the cause of this resistance is the repeated use of the same herbicide, selective pressure, and the creation of a selective population. He explained that to maximize herbicide efficacy, whether you are working with pre-emergence or post-emergence, there are important actions and steps to take. He concluded with some takeaway points: start clean, manage the weeds along field edges too, and use cover crops.

Then Dr. Anita Oberholster from UC Davis started her presentation about grape smoke exposure risk and mitigation for the vineyard and winery. She began with facts and statistics from last year’s devastating wildfire season and the economic effects it had on the wine industry. The characteristics of smoke taint and smoke tainted wines were discussed. Dr. Oberholster dove in scientifically on the chemistry of the grape and how it becomes tainted. She then explained mitigation practices for the vineyard and winery, what that looks like, and current studies. To conclude, she explained that smoke does not equal smoke taint, that smoke taint marker analysis is still a limited predictive measure, that there is no known mitigation in the vineyard, and finally that mitigation in the winery is limited.

To conclude the day, Dr. Stephanie Bolton with the Lodi Winegrape Commission closed with information about the Commission, what the REC Committee is and does, the Research Focus Groups, and the Commission’s viticulture research efforts.

Have something interesting to say? Consider writing a guest blog article!

To subscribe to the Coffee Shop Blog, send an email to with the subject “blog subscribe.”

To join the Lodi Growers email list, send an email to with the subject “grower email subscribe.”

To receive Lodi Grower news and event promotions by mail, send your contact information to or call 209.367.4727.

For more information on the wines of Lodi, visit the Lodi Winegrape Commission’s consumer website,

For more information on the LODI RULES Sustainable Winegrowing Program, visit or