Understanding the Yield-Quality relationship in Cool Climate Pinot Noir and Chardonnay

The long-term crop load study continued during 2018 for the seventh season of the project. Ten companies conducted research in 12 vineyards during 2018, including 11 Pinot noir vineyards and one Chardonnay vineyard. The report focuses on the results of the Pinot noir sites. The Pinot noir yields in 2018 were high, similar to 2015 and 2017, all high-yielding years for western Oregon. Average yield across all crop thinning treatments and sites was 1.16 lb/ft, which is higher than the 7-year mean of 1.02 lb/ft. The 2018 season was warm and dry and led to lower pruning weights and a higher yield to pruning weight ratio than in prior years of the study. Despite the higher yields and higher crop load, the 2018 season had fewer sites showing differences in fruit composition at harvest than in the six years prior with only 55% of sites having some crop level effect on fruit composition at harvest. The most common differences by crop level were higher total soluble solids and total anthocyanin concentration with lower crop level; however, the differences were not always consistent across the years or vineyards. Wine sensory results of past vintages indicate no consistent differences in sensory perception by crop level. However, in-house evaluations of wines by collaborators indicate that there are differences but it is difficult to identify a clear preference by crop level. Industry collaborators shared their observations about the study through interviews, reporting that higher crop levels have not affected vine health, and they report that fruit and wine quality is not as different as they expected it to be. Collaborators are starting to evaluate their target yield each year, rather than using the same target yield every year. Many reported that the study gave them confidence in increasing crop levels by 10-25% and helped them evaluate their farming practices with more data collection and interpretation. They want to encourage others in industry to learn from their experiences from this study and to think “smarter” about yield management.