Further into Pandora’s Box

For many years, I knew of this great geologist working her way through Burgundy. I saw her work for the first time when I received a disc, via Wasserman and Co., that Bruno Clair sent to help me with a Côte de Nuits educational seminar I was putting on. The disc, a dossier commissioned by the town of Marsannay, contains geological research submitted with the town’s request that certain lieu dit sites be elevated from village-level to the rank of premier cru. Her work is an extraordinary geological survey of Marsannay. The research goes as deep as you could imagine; any deeper and you’d be digging a hole with no end.

Today, the most welcome guest, in any cellar in Burgundy, would likely be the resident geologist, Françoise Vannier. Every vigneron wants her in their cellar so that she can help to literally unearth answers to their questions about the soils relationship with their historical terroirs and its influence on the resulting wine. She admits that it is challenging to be able to identify a soil through the taste of its wine, but she gives it her best shot. I suppose that many vignerons expect that her findings will provide them with a more clear understanding of their wines. I’m sure that they are disappointed to hear answers that only lead them to more questions and further into Pandora’s Box.

On this day, it was our turn, and we were ready to be taken further in. The Wassermans knew that I wanted to visit with Françoise and graciously arranged a rendezvous.  We met her in a parking lot in Beaune and jumped into Paul’s car and set the course Southbound towards Volnay and Pommard. She sat in the back next to Helen, our good friend and wine buyer for a number of restaurants in Los Angeles. I was glad that Paul was behind the wheel because I would not have been able to focus on the road with Françoise in the car and the vineyards of Burgundy all around. We all had a twinkle in our eyes as we had been looking forward to this for a long time. Of course, we realized that many questions can take an eternity to answer and usually only lead to more questions – such is life.

I knew it was going to be a special day. We all broke out our cell phones and started to record the conversation because we knew we were about to be treated to some of the most memorable – and mind-bending – hours of our lives. Some people want to know why we are on this planet and how we got here. I am the guy who prefers to know more about what I smell, taste and feel in wine. For me, learning about wine is more interesting, and definitely more rewarding, than debating deep and unanswerable questions.

Françoise sat in the backseat of the car, enthusiastically waiting, like a puma ready to pounce on any question we had. As we drove down the road towards one of my favorite, but least understood, vineyard areas within Burgundy, someone had to break the ice. But where do you start when you have a guru in your backseat? I threw it out there, “Can you give us an overview of the differences between the Cote de Nuits and the Cote de Beaune?” I bet she gets this question every time, and I’m sure she loves the response she gives. “Let’s talk about the similarities first because there are a lot more of those than differences.” I thought, “Damn it! Now I’ve misrepresented myself as a glass half empty guy, and she’s a glass half full person.” Regardless, I knew she was better than me; I could tell the moment I met her.

She went through the well-written history of Burgundy by talking about how the region, as we know it, began as a lagoon a couple of hundred million years ago. Then the story started to get more interesting. Between that time and a few million years ago, the Cote de Nuits and Cote de Beaune went through the same geological changes. Many books on Burgundy provide a much more in-depth account of this time, and I would suggest that you look into it as I will not attempt to explain that era. If you managed to stay awake while you read these well-written books on Burgundy, this piece of writing will make a little bit more sense. If you have not, I hope that you will find my account interesting. Françoise quickly moved to what occurred about 2.5 million years ago. She explained that after the tropical zones vanished, the area went through six Ice Ages. At this time, the soil was deeply frozen (permafrost) all year long. During spring and summer, temperatures sometimes rose above zero, but the water could not penetrate the frozen soils. This is how the small dry ravines called “combes” were formed throughout the Cote. They were not created by glaciation, but rather by this heavy water runoff. The combes cleave the hills into distinctive geological zones as well as creating a series of different soil components in the alluvial fans below.

As we arrived in the appellation of Volnay, we stopped the car. She got out and pulled out from the trunk a series of geological maps that a Burgundy lover would kill for. Of course, we were not going to kill to get the maps because we didn’t know how to decipher them…yet. In addition, her gentleness, passion and intelligence left us in awe and admiration. She is one of the most warming people I’ve ever met; in her presence, we were melting like beurre d’echire over freshly toasted bread. Now equipped with the maps, we jumped into the differences. She explained that the main difference between the Cote de Nuits and Cote de Beaune is that “you are not looking at the same stair steps.” The stair steps refer to the way the limestone slabs broke apart through faulting. She continued, “The important thing (between the Cote de Nuits and the Cote de Beaune) is that the rock is not exactly the same. Because the rocks of the Cote de Beaune are younger, they are richer in the soft marls, clays and shales. Therefore, erosion is easier than in the Cote de Nuits where you find much harder limestones. Because the substrata in the Cote de Beaune is easier to erode, the reliefs are not the same. What is also important is not the age, but the nature of the soils.” Yes, that’s it –what matters the most is how the soil performs in relation to erosion, water capacity, and nutrition. Can you even start to consider the complexity of the ground in Burgundy? Within five feet, things can dramatically change. We always attempt to use generalizations in order to get a better grasp; however, because the soil can change from one vine to the next, the variables are infinite and hard to identify on the surface. This was our first big step into Pandora’s box.

As we moved in front of an old quarry at the top of the Volnay-Santenots vineyard, just below the RN73 (yes, there’s an RN73, but no restaurant yet…), she began the next lesson.

Françoise Vannier

Françoise Vannier

For authenticity’s sake, you have to imagine Françoise orating with a strong French accent, “Between the villages of Dijon and Nuits-Saint-Georges, the hillside is North to South oriented, but in the Cote de Beaune the orientation is more Northeast to Southwest –here, you cross the faults. When you are in the Cote de Nuits, you are more parallel with the faults. It’s not the same lithology. … In the Cote de Nuits, because there is a lot of limestone, the erosion you have creates a more smooth hillside and a homogenous hill shape than in the Cote de Beaune.” She added that in the Cote de Nuits, the limestone (which are more resistant to erosion), create slopes that are of a concave shape (one notable exception would be the great 1er cru, Les Amoureuses). The topography of the Cote de Beaune, on the other hand, is more convex because you have layers of limestone mixed with layers of marl that are more prone to erosion. The soils are also lighter in color in the Cote de Beaune. “Since the faults were active around 25-30 million years ago, the erosional process has smoothened the landscape since then.” In other words, what you see above is hardly what you see below. Most of us have a reasonably good grip on this concept, but it’s nice to hear it from the world’s leading Burgundy geologist!

When you visit Burgundy for the first time, after reading books about faulting and fissuring, and you see a big limestone cliff in the middle of a vineyard, you may have the reaction I had, “wow, that’s some serious faulting!” Françoise explained, “When you have a landscape inside the cote that has what appears to be an open fault, they are likely a result of human activity, usually a quarry of some sort.” Yeah, I know what you’re thinking now, “how is it possible that any human can carve off a huge chunk of Bonnes Mares, or Chambertin and corrupt some of the greatest vineyards in the world?! That’s ridiculous!” Well, that’s what happened. Believe me, before the invention of dump trucks, it would have been a lot easier to build your house in Morey with the rocks from Bonnes Mares than to carry them by horse cart from the nearest non-vineyard quarry, a couple of kilometers away. Humans love to move rocks, and they indulged in this practice more than you would expect, even in Burgundy. Françoise added, “whenever you see piles of stones, you can also be sure that there is a limestone layer just below the topsoil in the vineyard next to it.”

“Can you explain active limestone?” Did I have to ask her this question? Of course I did. As we walked away from this former quarry, I saw a shiny white rock that sparked the question. The rock looked so solid that it seemed impossible for the soil to absorb anything from it. Her response: “If you have a piece of carbonate, with the arrival rain water (that is saturated with CO2), it will be easier to erode (the rock) because Calcium Carbonate is CO3 (on one side) and Calcium(Ca) on the other side. With bigger chunks of stone, however, it is more difficult to get more active calcium (because the surface area is smaller compared to the same big rock broken into tiny fragments).

Little rocks

The calcium and the carbonate circulate in the water close to the roots, where you have an intense chemical activity. At the end of the root system, you have an extremely acidic zone, which facilitates the dissolution of the rock.” Simply put, she explained that the “active” calcium carbonate is the measure of calcium and carbonate available to the plant. Amongst many other things, having the right amount of calcium is very useful as it helps to develop cell wall strength, enzyme activity, nitrogen uptake, decreased soil salinity and improves water absorption for the vine. On the flip side, the large quantity of active carbonate deposit may create a “casing” that surrounds the root system and may prevent huge elements, like iron, to be absorbed by the roots. For example, the leaves require iron to photosynthesize –this process makes the leaves turn bright yellow. This phenomenon is known in French as “chlorose ferrique”, which we call Chlorosis. She also mentioned that too much calcium carbonate in soils prevents roots from digging deeper. We limestone junkies celebrate its merits around every turn; however, it is important to realize that higher calcium content does not always mean better wine. Of all professions, we in the wine business should know that too much of any good thing can be toxic.

The rock I picked off the ground was a piece of hard, white Comblanchien limestone. I was convinced that this rock was physically too hard to give up anything. I was wrong again. Françoise explained that Comblanchien limestone is one of the most active limestones. “During the lagoon phase of sedimentation, the calcium carbonate particles precipitated and eventually under the pressure of the accumulation of this sedimentation, the water was ‘pressed’ out eventually creating almost a pure, hard stone of calcium carbonate. The stone is almost completely white because it is almost solely carbonate crystals –there are no fossils or other formations in it.” She explained that it is 99% calcium carbonate. It is the purest limestone of the bunch. By contrast, other stones in the Cote have 80%, or less of calcium, which is still a high quantity, and the rest is shale. Comblancien is basically a pure mud compaction. She further explained its purity, “Comblancien limestone is very hard to erode, but it is very rich in calcium carbonate. When you erode one meter of Comblanchien stone, you just get 1cm of soil because there is very little shale and clay in the Comblancien limestone.” If you can imagine those proportions: upon full erosion, only 1% of this hard stone’s volume remains.

Françoise grabbed her hammer and busted open another piece of limestone inside the Santenots vineyard. We could see all of the small shiny particles of shells broken into pieces by what she called “the action of waves.” It made me pause to conceive that the last time these shells were exposed to air was over 160 million years ago. 160 million years is a staggering number of years to get your head around… Françoise told us about how she used to think that, through taste, she would be able to find a correlation between the rocks and their resulting wines. As she said this, I looked over at Helen who was discretely licking the inside of one of these freshly smashed rocks. I smiled, and she turned a little red, “What?!” she burst out with a laugh. Then Paul started licking another piece of rock. Then I did. How ridiculous we would’ve looked to someone watching from afar… It was fun. We were like a bunch kids in a very savory rock-candy store… As Françoise watched us licking the rocks, she said with a smile, “I found out quite rapidly that this was not the case.” It was fun watching her aggressively smash rocks as she discussed each rock’s history. She explained, “Geologists always break the rocks to see a fresh break. Inside you can see different types of shells, mosses, lichens, oxides and all things that are hiding the true aspect of the rock.”

At this point, I want the reader to know that the next three paragraphs are about intensely geeky geological things. There are several interesting stories beyond these dense paragraphs, including one that will likely be a bit of a blasphemous surprise to us Burgundy puritans. If you are interested in geology and its relevance to wine, they are worth a read. I will attempt to explain two central points, as they were explained to us that day, that are crucial when digging into the geological side of Burgundy. You now have my disclaimer: Reader beware…

A couple of years ago, when I visited Pierre Morey for the first time, he claimed (as we stood in his section of Batard-Montrachet) that the quality of the clay is one of the most important considerations when discussing terroir in Burgundy. I asked Françoise what she thought about that. She said, “It is very important because it’s where most of the water and nutrients will be stored.” She reiterated, “It’s very important… You have very different types of clay depending on the distance between two sheets. The chemical composition of each sheet will not be able to store as many types of nutrients as other clays. In Burgundy, there are many types of clay, and it’s the blend of clays that make it unique, not any particular type of clay.” I want to clarify, briefly, what she means by “sheets”: Under a microscope, clay often looks like loose, torn sheets of papers spreading in all directions. When you move clay around in your hand, those microscopic “sheets” slide around like a stack of laminated papers.

An example of clay under a microscope

A type of clay under microscope

This is why wet clay is slippery when you move it around between your fingers. Clay is immensely rich in nutrients, but the trick is to get the nutrients out of this maze of microscopic sheets. Those sheets make it hard for nutrients and minerals to be available for plants. The reality is that most of the biological activity lies within Burgundy’s clay-rich topsoils, not deep into the stones below. Franz Weninger, one of Austria’s great biodynamic minds, once explained in a seminar that the water-sourcing roots are the ones that plunge the deepest into the earth’s dirt. They are not the principal root systems of the plant that gather the bulk of the nutritional components. Those roots are mostly located in the upper sections, closer to the base of the vine.

Then there is the shale, which I mentioned a few times in previous paragraphs. I would have been fine with sweeping this one under the carpet. It’s still a difficult concept for me; because it is relevant, I cannot pass this one over. As we drove down through “Caillerets”, one of Volnay’s top vineyards, Françoise attempted to enlighten us on what shale is. She said that geologists talk about shale more than clay. They often use both terms in the same sentence, which makes it seem like these two words refer to the same thing. They do not. She explained, “shale refers to the stone itself, and clay is the mineral.” She opened the box a little wider, “shales are the composition of the rock. Shale is a silicate (to name a few – quartz, feldspar, mica) that is not subject to weathering by the rain and that is not made of decomposed components.” She looked at me with an apologetic pain on her face. She knew I was a bit lost –probably like you right now. She apologized for the complexity of the subject. Paul asked me if that was a good enough answer. I said it was, but it still wasn’t clicking with me, and I sensed that the rest of the crew felt the same way. We started to slowly roll down the hill again, and I needed to get this straight. I was thinking, “If I can’t understand it with Françoise explaining it to me, I will likely never understand it by reading about it in some book.” Thirty seconds further down the hill, I had to ask, “Can we talk about this shale thing again?” She smiled and tried to make it more manageable for my pea-sized brain. “Shale is not a calcium stone.” That helped me breakthrough my limestone barrier. “It is made up of silica, aluminum and oxygen. Like clay, they are made up of sheets and are able to store between the sheets a lot of minerals, water and nutrients. It is a soft stone, and the clay is a component of it.” At this point, I felt like I had just watched the first third of the Christopher Nolan movie “Inception”: It was mind-bending, but I was slowly starting to catch on. The following information helped a lot too: “If you just have clay, you will have some shale (in the soil). If you have a little bit of clay and a lot of calcium carbonate, you’ll have a limestone. If you have more or less, half clay and half calcium carbonate, you’ll have a marl.”  Ok, halfway there…  As I was conducting some research to help me write this piece, I learned that the term shale is a general term for all kinds of clay-rich sedimentary rocks. However, I was left hanging as we drove back up the slope towards the center of Volnay. Later in the day, I brought it up again. I felt the mood in the car drop as everyone probably thought, “here he goes with that shale stuff again…” She explained that the more shale there is in the soil, the more “sticky” the soil is. Ok, that’s something tangible for my brain. “Wait a second. I’ve always thought of shale as a stone. So, are you telling me that this is the starting point on the way to becoming a stone, or the decomposition of the stone?” “Both” she said with a smile, “shale can be both soil and rock.” Got it. Done.

As we stood in front of D’Angerville’s most famous vineyard, the Clos des Ducs, Françoise spoke of the “two sides” of Volnay. Most people speak of four, but because we want to keep it simple, we’ll stick to two: The Pommard side and the Meursault side. “(In Burgundy) Geologically speaking you have some small valleys cutting the hillsides; and that represents the different geological environments.” She continued, “There is a bigger (geological) difference between the northern part of Pommard and the southern part of Pommard than there is between the southern part of Pommard and the northern part of Volnay. (Got that?) The limits are between one valley and the other, not the appellation lines.” This distinction is crucial when looking at maps of Burgundy. Almost all maps feature appellation lines rather than geological demarcations. Because she has not yet published the geological maps of Pommard or Volnay, I will use Marsannay as an example. If you look at the geological map of Marsannay below that Françoise created, you will see how the combes cut through the hillsides and how geologically different the sections of Marsannay are.  Marsannay-3D-geology-copyIn order to experience some of the differences, all you have to do is taste the range of Marsannays from Joseph Roty, Sylvain Pataille, Cyril Audoin or Bruno Clair. Like all of Burgundy, Marsannay is a wonderful subject of geological study – especially once it is poured in the glass – and Françoise’s geological map should illustrate that pretty clearly.

We eventually found our way through Volnay and into Pommard where we stopped at one of the village’s greatest crus (maybe the greatest), Les Rugiens. Fortunately, Françoise was already familiar with Pommard as its syndicate hired her to conduct a thorough geological study. When we arrived, she broke out a diagram of the lithological succession of Pommard and began to tell us about the limestone structures. With an enthusiastic smile, she pulled out a geological map of Pommard. She told us that the first time she came to the village, the vignerons expected her to take out her hammer, start breaking rocks, and explain everything on the spot. What she discovered there surprised everyone in the appellation. To demonstrate this discovery, she grabbed her hammer in front of us and smashed a piece of rock until it broke into a couple of pieces. She showed us the inside of this rock, and confessed that it took her three days to figure out what this type of rock was.

She explained that after the fracturing of the limestone – some 30 million years ago – there had been water very rich in magnesium circulating in this specific area. The magnesium is able to combine with the carbonate to create a different type of limestone-like rock, called dolomite.

The dolomite rock she demonstrated with

The dolomite rock

Today, this is the only known location in the Cote d’Or that has this type of stone. So, what is so special about this stone? This discovery gives Pommard, as Françoise says, “a clear specificity.” In addition, the vineyards are rich in magnesium, which greatly contributes to the formation of chlorophyll and photosynthesis for the vine. The vignerons of the appellation confirmed that they are never short of magnesium supply in their vineyards, and now they know why. Pommard has always been one of the most intriguing and complex appellations; this finding makes the appellation unique and special within the Cote d’Or. As we stood next to Les Rugiens, she also mentioned that it is easy to see that Les Rugiens Hauts is influenced by slope wash with whiter stones overlying the dolomite stone, whereas the Les Rugiens Bas has more reddish soil and less dolomite. Paul confirmed that they generate two very different wines. Time to spend some money on Pommard…

Then there was the Romanée-Conti story. Towards the end of the day, Françoise told us a story that would make any Burgundy lover cringe. In the southeast corner of the Romanée-Conti vineyard, there is a hollow in the substratta. In her opinion, it was likely a former rock quarry within the vineyard. She said that there are manuscripts from the mid-1700’s(1) that mentioned “carts of earth being brought into the Romanée-Conti.”  The soil in this particular part of the Romanée-Conti is a mixture of both soil in place and an external input, as in so many other plots in Burgundy. Yes, you are reading this right… the greatest vineyard, producing the most expensive wine made in Burgundy (or the world for that matter) has a good chunk of soil that was not formed in its present position.  Further into Pandora’s box…

As interesting as this discovery is, it is not one Francoise is excited to share. Like us all (who have made it this far in this story), she is a Burgundy lover, and this finding, to some degree, may take away a little of the romance that defines this region. She told us that some soils from the Cote d’Or show clear evidence that bringing earth from elsewhere was a common practice before the rules of the AOC system were in place, not just in Burgundy, but everywhere. Françoise suggested that when some Burgundy producers had a loss of soil from erosion, rather than buying earth from their neighbors at a high price, they would often go somewhere else to get some cheaper earth. This leads me to the next subject, terroir.

Many vignerons believe that man is a part of the terroir.  In my mind, Françoise made a very convincing argument in favor of that perspective.  With her strong and stern French accent, Françoise continued, “At the beginning of the 20th century, we imagined that, centuries ago, the monks just came in and put away the bushes, put in the vines and everything has been created and natural and has never been transformed by human activity.” There was a slight pause, and then she said, “It’s wrong.” She continued, “Human beings have been here a long time. They needed to go from one place to the other. They created roads and built houses and walls by taking stones from the vineyards. Now, it’s a monoculture, but up to the end of the 19th century, you had d’autres cultures, like vegetables, and fruit trees. There were a lot of trees where vineyards are today, but today it looks like a green ocean. If you look at an aerial photograph of Burgundy just after the Second World War, you will also see many quarries where vineyards are today.” As we stood in the most northern part of the vineyards of Pommard, she pointed across the hill, “that part of the Clos de Mouches was a quarry, not a vineyard. It’s hard to imagine at this present time that the landscape has not always been the one we’ve got in front of us.”

When we started our day with Françoise, I was excited to bring up a number of concepts that remained somewhat unclear to me. To be honest, I’m sure that most, if not all, of this is in a book somewhere, but most of the things I shared in this article were pretty new to me. Our visit with Françoise was the greatest visit I’ve ever had in Burgundy, and we didn’t even taste a single wine. I guess you could say that she is Burgundy’s rock star, and that was enough. Despite her status, she explores her subject of study with a high level of respect and humility, qualities that are often rare in the “non-vigneron” side of our business. Because she is a thoughtful and open-minded scientist, she explores thoroughly her discipline while keeping in mind that geology is only one of many factors giving wine its expression. I also love seeking out correlations between the taste and smell of wine and their rocks, but I realize that this practice only casts light on one piece of an extensive and extremely complex puzzle.

I thought that my day with Francoise would give me a more clear view of Burgundy and wine as a whole. As usual, I was wrong. It only served to spark more questions, more thoughts, and more feelings, not just about wine but about everything that I think I have a decent grasp on. Every day I realize more clearly that reality and my perception of it are not quite the same thing. My visit with Françoise convinced the committed terroirist in me that the role of man in transmitting terroir is as substantial as the role of nature itself. After all, the vines aren’t putting the wine into the bottle themselves… This day with Françoise also encouraged me to engage in a deeper and more philosophical relationship with the nature of nature. Because nature has no ego or insecurity, the more time I spend with her, the more distant I find myself from mine. If a better understanding of wine does not humble the person acquiring it, then their engagement was never really about the wine. Wine is a good reminder that no matter how much we think we know, there is still so much we don’t know.


(1) Garcia J.P., 2011, La construction géo-historique des climats de Bourgogne, p. 103, note 5, in « Les Climats du vignoble de Bourgogne comme patrimoine mondial de l’humanité », sous la direction de J.P. Garcia, pp. 97-122.