CAMPAGNA FINANZIATA AI SENSI DEL REGOLAMENTO CE N. 1308/13
CAMPAIGN FINANCED ACCORDING TO (EC) REG. N. 1308/13
This vintage was warm and it seemed to confirm the global warming trend. This is visible from the graphic of the GDD -growing degree days- (fig. 1), i.e. the summation of the temperatures higher than 10°C recorded during the vegetative period, from April to October. This parameter indicates the heat (energy) the plants can use.
Fig. 1: GDD (Source: R.A.M. Regione Piemonte, hotspot in Barbaresco)
The 2015’s GDD is around 200°C/day higher than the latest 5 vintages. This is also confirmed by the analysis of the maximum temperatures (Fig. 2) where we can also observe a consistent and constant rise of the temperatures: about +3°C during the Spring and up to +5°C in July. Exactly in July recorded daily temperatures were between 35° and 40°C.
The warm climate influenced clearly the growth of the sprouts: speeding it up at first and then slowing it down. This is because too-high temperatures limit the photosynthesis and thus stop the production of sugar. 40°C is the threshold temperature, but from 32°C the photosynthetic activity is considerably slowed down already.
Fig. 2: Monthly average of maximum temperatures (Source: R.A.M. Regione Piemonte, hotspot in Barbaresco)
In 2015 rainfall reached 700mm, i.e. a bit less than the average. As illustrated by the graph (fig. 3) Spring rains were concentrated in February and March (respectively 155 mm and 175 mm rainfall). Thus most part of the Spring was particularly dry (40 mm rainfall, instead of the 80 mm in March and April on average). The consequences of the warm climate were amplified by scarce rainfall during the Summer period (July), thus showing symptoms of drought on the vines, like the drying of cirrus and tendrils (phylloptosis).
Fig. 3: yearly rainfall (Source: R.A.M. Regione Piemonte, hotspot in Barbaresco)
The climatic trend, warm and humid during the beginning of the Spring (February, March) fostered the early opening of the buds, while the high temperatures during the following months determined their fast growth, quickly causing blossoming.
From the phytosanitary point of view, the vintage didn’t cause problems of mildew (Plasmopora viticola), while, on the other hand, powdery mildew (Oidium Tuckeri) took advantage of these climatic conditions being highly infective.
The Summer period has been the most difficult one: the excessive dry heat caused the symptoms of the drought, especially in the youngest and most-exposed-to-the-sun vineyards. To achieve proper phenological maturity, adapting green pruning operations to the climatic conditions according with the features of the vineyard and the amount of the row hit during the warmest hours of the day, has been a crucial factor.
From the physiological point of view, the vines, slowing down of the photosynthesis, also slowed down the ripening of the grapes. This phenomenon was apparent especially for late-ripening black-berry varietals. The harvest of the Chardonnay and Moscato started between the end of August and the beginning of September. Immediately after, Arneis and Dolcetto, were harvested during the first ten days of September. The Barbera and Nebbiolo varietals took benefit from the lowering of the temperatures, becoming ripe around the first ten days of October.
The results achieved so far in the cellar are promising: the vintage gave us full-bodied wines, which are, at the same time, gentle and round.
Roberto Prandi, Sergio Belmonte