Statewide Crop Load Project: A Researcher-Industry Partnership to Understand the Yield-Quality Relationship in Cool Climate Pinot noir and Chardonnay Production

The Statewide Crop Load project was conducted in 13 vineyard sites in 2016, including 12 Pinot noir vineyards and 1 Chardonnay vineyard. Results of the Pinot noir vineyards are reported here for data obtained as of this reporting and data are still pending from the Chardonnay vineyard. Yields during 2016 were down from 2014 and 2015, the highest yielding years of the project and were similar to yields obtained in 2013. Average yield across all crop thinning treatments and sites was 0.85 lb/ft in 2016 compared to the 5-year mean of 0.89 lb/ft. Heat units (GDD50) in 2016 were also lower than in 2014 and 2015, but harvest was earlier than the past four years with all harvest completed by the end of September. Fruit composition data indicates advanced ripening with total soluble solids ranging from 24.3 – 25.6° Brix for 2016. Analysis of fruit composition data across all sites in 2016 revealed that vineyard site, not crop level, led to differences in fruit composition. Treatment effects were tested within each vineyard site, and results show that the majority of sites (82%) had some treatment effect on fruit composition; however, the effects varied by site. No one fruit composition parameter was affected by crop level at all sites, and the most common differences found by treatment were for pH, titratable adidity, tartaric acid, and tannin in 2016. However, this effect was found at approximately one-third of vineyard sites. Furthermore, few crop level effects were found for anthocyanin content in 2016 while 15-28% of sites from 2013-2015 had higher anthocyanin with lower crop levels. Further data analysis of vine growth, fruit composition and wine sensory is underway. Sensory evaluation has been expanded to include new in-house wine evaluation methods that were developed in 2016 for implementation in 2017. To capture industry-collaborator observations from the study to be used to enhance data interpretation and to develop yield management metrics, survey and interview tools were developed in 2016 and will be conducted in 2017. Updates on this project will be provided in future grant reports and outreach to the industry.