Developing accurate estimates of crop yield and canopy size is a challenging, critical task for grapegrowers. Regardless of how you develop your estimates, crop weight and canopy estimates impact a variety of business decisions, including how to optimize fruit quality and manage the logistics at harvest. With accurate estimates, you […]
Historical context Why measuring sap flow leads to understanding nutrient uptake? All vine organs are connected via the sap. Thanks to the flow of sap, nutrients are distributed to plant organs. For the last 10 years sap flow technogies have given new insights into how much water flows from vine […]
Update on Napa 2016 vintage, First half of the 2016 season illustrates the effects of warmer temperatures in a context of low water deficit due to high rain supply earlier from El Niño. The 2016 vintage is a unique opportunity to tease apart the effect of warm temperatures alone while […]
After harvest ended in Bordeaux for whites and reds, comments and articles about the 2015 vintage were all over the web : it seemed like another great vintage. At first, during the summer, 2015 was expected to mimic 2003 due to the extreme heat and drought in July. Now that […]
Several definitions exist to characterize grape berry maturity: technological, aromatic, polyphenolic, and enological: Technological maturity is the time point beyond which berries do not accumulate more sugar and do not lose any more acidity. Phenolic maturity takes into account the quantitative and qualitative evolution of the berry polyphenols in the skin (anthocyanin […]
As season goes by and the first berries enter veraison, 2015 promises to be a very hot and dry vintage. Despite a late bud break early April, the 2015 season is now turning into a very early vintage, catching up with 2011. This catch up is explained by temperatures in […]
Thanks to a grant received from the Water Metropolitan District of Southern California, we set up an experiment last year with the help of 6 independent wineries, under contrasted California climates. The goal of the experiment was to evaluate how much irrigation water could be saved and how was affecting yield and maturation compared to […]
As we enter veraison, we observe that the window during which berries are changing color is stretching due to the weather cooling off. What does this mean for the uniformity of ripening? Traditionally it is assumed that the rate of ripening is uniform between berries. Consequently, when a berry turns […]
Predicting the onset of budbreak, bloom, and other phenological stages, is a very active topic of research. Recently, new results regarding the effect of winter temperature at hastening the onset of budbreak have been reported. Parker et al (2013) have suggested that the effect of heat accumulation on vine phenology […]
California is experiencing its fourth consecutive year of drought. So far 2015 vintage is even earlier than last year, which is logical considering the faster heat accumulation recorded during the first four months of the year. Consequently dates of budbreak and bloom are on average 2 weeks earlier than 2014. […]
