Any vineyard owner will tell you that certain areas of their vineyard make better tasting grapes than other areas. Why some areas of vineyards and vineyard districts deliver better grapes and hence better wine is the subject of terroir studies. The Europeans and particularly the French are very interested in this topic. They extend the meaning of the word which we can roughly say is the flavour effects that come from the vineyard location to include cultural ideas which unite man with the soil.
‘Terroir’ tries to draw together all of nature’s contributions that can affect the taste of wine with a strong emphasis on rocks and their weathered product soil. The type site is of course Burgundy and the detail here is excellent. A series of cross sections over the great vineyards produced from shallow surface seismic work gives great insight into the soil profiles. Never have I understood better the relationship of Chevalier Montachet to Montrachet to Batard Montrachet than by seeing the cross section diagram. A strong control on grape quality is of course the climate but these vineyards are so close together that other explanations are needed to explain the differences in taste and it becomes apparent from this detail that the slope angle, soil mix and depth of soil and water retention are key factors.
Chablis also becomes clearer and while it may not be Wilson’s conclusion the Grand Cru vineyards are great because of the perfectly angled slope that captures more of the climate versus nearby vineyards with the same geology which are not as well exposed, particularly to the sun.
Alsace like Burgundy is controlled by major faulting and they create the river valleys of the Rhine and the Soane. Alsace is much more complex in the way this faulting has shaped the land surface and has created a diverse range of soil and mixed soil and rubble surfaces. Numerous rock types are bought to the surface in an intricate and fascinating manner creating an oblong, chess board look. The 50 or so Grand Cru vineyards are spread along 96 kilometres. Some growers maintain that each vineyard is exactly fitted to the correct grape variety. There is no doubt that some vineyards make superior wine and thus no reason to doubt for example that pinot gris or gewürztraminer show enhanced floral aromas and flavours in certain vineyards. Still the wide variety of aspects and soils shows that great wines from the same variety can be made in many different surface locations in this region.
Of interest is that winemakers from Chablis and Alsace who have spoken in Australia over the last few years are the most ardent supporters of being able to taste the flavours of the location in their wines and may even say they can taste the influence of the vineyard rock type.
The descriptions of the geology and soils of Bordeaux are also excellent and these are tied very closely to the best vineyards, especially on the south bank. The explanation of the setting of Chateaux Margaux, finally makes it clear to me why this wine has always tasted differently to the other first growths such as Chateau Latour and Chateau Lafite.
There are many interesting conclusions that can be drawn from this book some of which can be applied to Australia. Though it must be remembered that Australia becomes the old world as the soils, the weathered rock, and the land surface, are so different. Post glacial soil development in France may be under 10,000 years whereas this is very young for Australia. Parts of the Barossa Valley weathered surface, which is under the soil surface, could be 20 to 50 million years old. Our youngest vineyard surfaces are at places like Mount Benson, South of Robe S.A. which are only tens of thousands of years old.
Those who have travelled in France and Germany know how important the vineyard slope is to maximize sunlight exposure; though with our constant sunlight it has less bearing unless the vineyard is in Tasmania or some of the marginal climatic mainland vineyards. Slope is also important for drainage, for exposure to cooling breezes and to catch rainfall and this is maximized with absorbent soils. ‘Terroir’ makes it apparent that weathered rock that has a variety of sources builds up a better soil profile for the vine. The long section describing the soils of Champagne and how the older calcareous weathered rocks are best when mixed with particles from younger lignitic rocks (a low grade of coal) is very convincing. This mixing is also explained in the Alsace region and is an important insight.
Perhaps most of this was known but the detailed manner in which it is set out is authoritative. Sections like that detailing the soil profiles across the best of Burgundy are valuable new information. Also so many of the vineyards in France are related to the weathering of limestone that you must conclude it is the favoured rock of the vine. We have some limestone such as along the Limestone Coast but it is not common elsewhere. Also there are many references to red wines liking limestone soils but its better when it is mixed with silts and clays or to use an imprecise term, reds like heavier soils than whites. Reference is also made to the depth of root penetration and it would seem the more physical and chemical variability of soil layers for roots to grow across the better.
This book received little attention on release and while it is specialised and perhaps not for the general wine enthusiast the comments made by a few of the major wine reviewers came as a surprise. I recall a review in the influential American wine magazine ‘Wine Spectator’ by Harvey Steiman. In a short review he said the following; ‘unfortunately he too often fails to link the geology to the character of specific wines’. At the end of the review mention was made of how he could now picture the soils and slopes of French vineyards but, ‘I just wish he had applied as much diligence to correlating all of that to the individual wines’. I find this a very harsh judgement. James Halliday, said in the Australian Gourmet Traveller, April/May, 2002; in a brief reference to the book; ‘and utterly failed to show a convincing connection between geology and the wines of any of those regions’.
The geology of any area covers the rock types, the weathered rock and soils and the formation of the landscape. That’s it. It cannot relate any facet of these elements back to the taste of a wine. ‘Terroir’ gives many plausible examples of why vineyards close together produce wines of different flavours and it does confirm how that relates to the geology. This type of information is specific to each area because geology is so variable, meaning the information gleaned is also not directly transferable. Geology sets the scene but it cannot suggest that this wine tastes like slate or tastes of specific minerals in a way that can be related back to the rock geology. Naturally these explanations come well after each area was planted and it is doubtful if detailed ‘geological’ surveys would be of much use in a continent that had not seen vines. Better to find where the grape likes to grow by trial and error. The geologist in this case came along well after the event when the different tastes had already been worked out. What is does do is give us a better understanding and confirms why areas are different. In the new world this is still not decided and these sorts of studies may have much more use.
Wilson’s book is interesting in another way as well because it shows how rapidly wine commentary is evolving. On reflection it is now obvious that the Hugh Johnson wine atlas published in 1971 altered the way we imagine wine and this book continues the trend. The third edition of ‘Alsace its Wine Garden, Cellars and Cuisine’ by S.F. Hallgarten published in 1978 has less to say about Alsace than this book, confirming that a map tells a thousand words.
It has though left me with one query. Since aspect is so important for European vineyards why is it that the great vineyards of Burgundy and Alsace must face East but the lonely area in between, Chablis, has its best vineyards facing South West?