Who is Pedro Parra?
A French-educated Chilean, who looks at the definition of terroir through the use of modern scientific techniques. The Old World has many hundreds of years to experiment, but in the New World, we do not have luxury. From my interview at the Vancouver International Wine Festival, find out how Pedro determines terroir and the best grapes to grow for wineries around the world, and here in the BC Okanagan.
My Interview With Pedro Parra, Terroir Hunter
What drew you to wine?
That is a very difficult question. I wanted to escape from Chile so I went to France to study at Montpellier University (Masters in precision agriculture). I was French educated in Chile through Alliance Française and Universidad de Concepción (Forestry) for 15 years. I received a grant to study in Montpellier in the south of France. I was working on soil and then when I started my thesis, I was invited to do it in Paris, Institut National Agronomique Paris-Grignon. There was a terroir research program there and because everyone was into terroir, I started to hang out with the researchers for fun, and the interest grew. I went back to Chile and later decided I wanted to apply for a PhD from Institut National Agronomique Paris-Grignon. They said ok, but only if you do it on terroir.
What are the most important components of terroir to you?
It will depend on where you are. I think every place has a very important primary component, but it is not the same everywhere. For me in Burgundy it is how the limestone fractures. Here so far in Canada it is the amount of limestone. The most important component in Cornas is how fractured is the granite?. These components are always related to air and stone. You want to have air in the soil so you have good drainage and space for roots. I also want the stones to feed the deeper roots, and not upper part of soil.
You do trenching and mapping, but briefly explain how you evaluate a new vineyard site.
It took me years to find my own technique. On my first visit of 1-2 days is to figure out the geology of the area. When I have an idea, my next step is to figure out if there is one or more geologies at the site. It can be tricky to determine. When I have the geology figured out, I bring the parameters together that I think are important for that geology. If it is a granite-based soil, I only think about granite parameters.
To figure out the geology, do you dig trenches?
You walk the vineyard and look at soil colour. You look at the topography. You get a first idea and then you dig a few strategic pits. 5-10 pits, done quickly. When I know the geology, then i know the geological structure I will work with. Many times as a consultant, you find a geological structure that is very difficult for grapes, there is a huge possibility that the land produce average grapes. That is hard when you have a passionate vineyard owner that wants to make the best wine, but there is no good geology.
How do you know when the geology near the surface or the rocks deeper in the ground will make better wine?
It depends. When the rock is very superficial and the soil is shallow the soil fertility will be medium to poor. As such, the vigor of the vines will be medium to low. If the region is sunny then the grapes will get sun burn. You can bring up the vigor to using fertilizer or watering, but this is not natural; its like using cocaine. Once this external application is removed, the vines will crash. If you have the same soil situation in a cloudy place, where the grapes do not sun burn, the situation will be different. So shallow soil will be better in some places and a problem in other places. Weather, root-stock, and the skill of the viticulturist all affect grape-vine vigor.
I teach and use Geographic Information Systems (GIS). How to you use GIS for vineyard mapping?
I need to really know what I call the spacing problem. It is not enough to know that I have 2-4 terroirs within a vineyard site; I want to know the exact boundaries. One way to do this is to dig lots of pits. One client made 600 pits in their vineyard. But that was in the past. Now we use GIS combined with high accuracy GPS info, and soil electric resistivity. The amount of electric resistivity in the soil is related to clay content. I want to know where I have more/less clay. If there is less clay and I know the geology, I know that low resistivity may be caused by stony or sandy soil below. Stony soil is better terroir than sandy. But with resistivity mapping we do not know without digging if we have stone or sand. So we dig. I use the GIS to create the electric resistivity maps, then I overlay a regular grid of posts across the vineyard that are labelled. I try to make a map in the GIS combining vine vigor with electric resistivity and any dug pits. I use GIS alot, in particular I use the QGIS software.
Do you use a spectrometer to measure leaf vigor?
I use NDVI images from aerial images to measure leaf vigor. You can have a drone with a camera to image the canopy in the infrared and red light, or you can use the same camera but hold it and image the canopy from the side to create the infrared and red light images. Alternately, you can have a person walking the posts and have them manually classify the vigor on paper, then enter it into the GIS database.
I use QGIS daily when I am working. I can create my maps so I know more about the soil, geology, vigor, topographic surface, etc. In my opinion, every viticulturist should know about GIS.
When you finish evaluating a site do you give the owner all the data and show them how to use QGIS?
I cannot teach them because that takes too long. Normally when I work for a winery, I am there for 6 days per year. My time must be focused so I cannot spend time teaching GIS. I advise them to hire someone with GIS knowledge (like Karl @mywinepal). I think you cannot grow the best grapes if you do not know the most about your soil and terroir. It needs to be quantitative knowledge.
Today in Chile and Argentina, everyone is using GIS, electric conductivity, and vigor maps. It is good if it will happen here. So far I think Haywire is the only winery using this technology in BC. Location of vines is important. In Burgundy it is all about location. They have many hundred years of history to rely on; we do not have history but we have GIS.
You need to know that a vineyard is made of micro-terroirs and then where we have to put the boundaries. It cannot be a guess to within 3-4 m of position. We need to be more accurate, but it will take time.
With global warming would you say some New World areas are getting better terroir, and other Old World regions are having their terroir degraded?
Yes, definitely. I go all around the world and see it every day. Places that had a balanced terroir are now a little warm. Places where the balance and root-stock were perfect are now not perfect. In places that were rainy, there is less now, and are now becoming interesting for grapes.
Has BC planted the “right” grapes in your opinion?
I would say that in the places where I work, BC needs to learn more. It is too young. If you want to see what they planted, they planted everything from Riesling to Cab Sauvignon. The weather is different in the Okanagan. Some places are warmer and others are cooler, but overall cool (warm-cool and cool-cool areas). You need at least one generation to understand which grapes do well at a vineyard. You can have a feeling about which grapes will do the best, but you need time and you need to taste alot. You also need to taste with people who are not from here. If you taste with people from here only, you are too familiar with the wines. You need an outside opinion. Their opinion will be different and will open up your mind. For sure so far, the white wines in the Okanagan are great. There is a huge potential for white. The reds currently have medium potential. Cabernet Franc can be done very well here.
Grapes like Riesling, Pinot Blanc, and Pinot Gris do very well. Grapes like Sauvignon Blanc do well to very well. I have not yet tasted a Chardonnay at the same level as other grapes in BC. For reds, I think that Pinot Noir is in general very interesting. I like it very much, but we are not yet in the top quality division (like Burgundy). I think there is the potential for top quality division but not yet because the vines are too young, and the viticulture is not focused on Pinot Noir.
1% of terroir of Burgundy is Grand Cru. 7% is Premier Cru. In the Okanagan we need to find the 1% and the 7%. To do it, you need to spend time and effort to investigate. You will never do it in 5 years.
Some say Cab Franc can be our signature red grape for the Okanagan.
I would say that this is credible, but you need to go to Saumur-Champigny in France and taste a lot of Cab Franc as the terroir is similar to here. The Cab Franc there is fantastic. If I had time and money I would invest here in the Okanagan. I would look for stony limestone soil and grow Riesling, Pinot Gris, Cab Franc and Pinot Noir.
What makes BC Pinot Gris unique? Fruit, mouth-feel?
First it is mouth feel. The combination of the particular soils and how it creates tension, minerality and freshness in the mouth. Plus these wines have elegant flavours.
I keep telling people that Pinot Gris has good potential.
More than good. Very high potential.
Thank you and Gracias to Pedro for spending time to talk to me about BC wine, terroir and GIS at the Vancouver International Wine Festival.
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