I’ve discovered the research done by The Association Cellule Terroirs Viticole few months ago in the middle of my Wset studies. Honestly, I have never seen such a detailed study, which analyzes soil in different wine regions. If you take a look at the website Techniloire.com and select e-terroir, you will find a map of Loire Valley divided into its sub regions.You can easily select a plot of soil and the analysis will show you: the age of the soil, the composition, the depth, information about drainage, sensitivity to erosion and much more… The detailed information amazed me, especially in a wine region known with its diverse wine style. I shortly contacted Etienne Goulet, the director of the studies. He kindly answered my questions and explained that terroir studies started in the middle of the 90’s, with the initiative of Rene Morlat, a researcher scientist at INRA (French National Institutue Agricultural Research) and with the help of local wine professionals. ‘Nobody spoke about the terroir’ says Etienne Goulet, ‘it was a real innovation to work on explaining how vine functions and how the quality is effected by environmental factors like soil, climate, geology…’ Apparently the interest of wine professionals and local scientists brought the knowledge of terroir to this point. The association ‘Cellule Terroirs Viticole’ conducts the studies and it is founded by ‘InterLoire’ (Interprofession of Loire Valley wines) and IFV (French Vine and Wine Institute).
There are similar studies around the world, such as McLaren Vale’s Scarce Earth project or Barossa Grounds Initiative. However, none of them are as detailed as it is in Loire Valley. The main goal was to give applicable guidance to winemakers. The results are accessible to all vine growers through the maps of terroir units, cartographic atlases and advisory maps. As Etienne Goulet point out ‘In order to make the results usable at plot scale, one had to go on the field, to study the profile of the soil with a hand auger. (Two or three hand auger profile by hectares at least) Also, one needs several samples for a certain area. For instance, if only one sample is taken for 10 hectares, it doesn’t bring healthy results.’ It is apparent that the process is costly as it requires meticulous work and time.
I wondered how many wine producers started using this application. According to several surveys, large number of producers knows about the study and about one quarter of the grape growers have really been influenced by the practices of terroir studies. (Goulet and Morlat, 2011) Etienne Goulet also gives examples of various applications:
Adaptation of crop management: One third of the growers adapted their crop management in relation to information provided by advisory maps in the atlas. This corresponds to 43% of the total vineyard area of wine farms that were surveyed. (643/1479.5 ha)
Changes in agro-viticultural practices: Almost 40% of the growers told that they had changed their agro-viticultural practices. Some growers did it in relation to the recommendations given in the atlases.
I was also curious if they were planning to expand their study out of Loire Valley. Apparently they are already working with companies like Sogrape Vinhos in Portugal, and other companies in France. However, they do not have a study in collective scale (for a specific AOC for example). It seems like some regions already contacted the Cellule Terroirs Viticoles, but Etienne Goulet says not all of them have the patience and determination that the Loire Valley has
Special Thanks to Etienne Goulet for the interview…