The Cool Night Index The Cool Night Index was created to study nocturnal conditions of grapes ripening according to the different wine-making regions (Tonietto, 1999 ; Tonietto et Carbonneau, 2004). By convention, this index is also called nycthermal index and is equivalent in the North Hemisphere to the minimum temperature […]

This discussion is a follow up with our last blog on the 2017 maturation What is the situation end of september? A general disorder in sugar accumulation is observed in northern California. The trend is widespread and shows sluggish sugar accumulation rate across many different vineyards. The extend of the phenomenon indicates […]

Leaving more growing nodes per vine at pruning (to increase vine productivity)  and applying  deficit irrigation strategies (to increase fruit and wine quality) are are widely used  practices, particularly in high yielding vineyards under  warm climate. However one may ask how those practices impact vineyard longevity and sustainability ? To […]

How can a winegrower harness vineyard spatial variability to make better wines?   Numerous studies carried out since 2000, on irrigated and non-irrigated vineyards have shown that vineyards exhibit great spatial variability for many factors such as yield or berry quality components (Santesteban et al, 2013). This spatial variability can […]

The use of NDVI in agriculture is no longer a new idea. As a result of numerous publications demonstrating the capacity of this measure to assist vintners in their technical decision-making, the number of NDVI maps  providers has increased considerably in recent years. Given the many choices available, winegrowers may […]

NDVI is an English acronym meaning Normalized Difference Vegetation Index, which could be translated as a Normalized Vegetation Index. This index reflects the quantity of so-called “photosynthetically active” biomass. It is calculated according to the formula: Where R and PIR are respectively reflectances measured in the red and near infrared […]

Phenolics within the grape play an important role in a wine’s sensorial properties, such as color, astringency, mouthfeel, and bitterness. For example, increasing the size of tannin molecules will increase astringency, or a higher level of epicatechin-3-O-gallate (ECG) will lead to more chalky dryness and a lower coarseness.  Thus, vineyard […]