San Joaquin Valley grape growers reduce fungicide sprays
Grape leaves at a vineyard weather station are examined by Steve Vasquez (right) and UCCE advisor emeritus George Leavitt.
What Has ANR Done?The UC Cooperative Extension viticulture advisor met regularly with San Joaquin Valley grape growers, focusing on powdery mildew disease. Using local weather data from the Fresno-Madera Weather Network, the advisor has shown growers how to implement and organize the PMI to develop spray programs using fungicides of their choice.
Growers save time and money, and help improve air qualityOnce growers see the exceptional results enabled by the PMI, they often commit entire vineyards to the new program. On 40-acre plots, growers can reduce costs, per eliminated application, of $149 when using dusting sulfur, $282 when using wettable sulfur, and $689 when using a sterol inhibitor such as fenarimol. Many growers have eliminated three sprays when conditions were right.
Clientele TestimonialThe Fresno-Madera weather network is one of the single most important Cooperative Extension services for California’s raisin growers. It has saved us substantial amounts of time and money, while reducing pesticide applications.
-Peter Miroyan, Fresno raisin grower
Supporting Unit:Fresno County Fresno County, Madera County and Integrated Pest Management
Stephen Vasquez, former viticulture advisor, UCCE Fresno County