Mountain vineyards in Europe
A mountain and a steep slope viticulture have existed in Europe within living memory. Mountain people have always utilized the capacity of vines to live on poor and pebbly soils; therefore they planted vines on the slopes with the best exposure, slopes that were sometimes inaccessible event to cattle. In the mountains there are, of course, strong limitations to viticulture, due to the surroundings. First of all the altitude that causes the cooling of the climate which is affected by latitude. Actually, while in the North of Argentina, at a low latitude, there are vineyards up to 2500 metres of height (Donald Hess, owner of the Colomé Estate, just planted a vine more than 3000 mt. high, aiming at winning the world title...), in Europe most mountain vineyards can be found between the 40th and the 46th parallels and not over 1000 meters of altitude.
Viticulture in the Alps
The southern slope of the Alps is entirely in the Italian territory, and in this slope the highest vineyards can be found. Here, most valleys are oriented from North to South, but mountain viticulture has been more successful in the few valleys oriented from East to West, in the Northern orographic slope, exposed to the South, and protected from the North winds.
In these valleys the rainfall is scanty, above all in summer (see further data), the brigthness and the sun radiation are strong and the termic range between day and night is high. The thermic difference between summer and winter is considerable, but lower than in Eastern Europe, or in the centre of Asian or North American continents, at the same latitude, due to the mitigating effect that the Mediterranean sea, which is a warm sea, has on the Alps region. This effect is stronger in the Western Alps (Val d’Aosta) than in the centre of the chain (Valtellina), as one can see from the data further reported. A character of all the mountain climates is the strong variability between different spots, even at a short distance: the altitude, the exposure to the sun, the direction of the prevailing winds, in a situation of low relative humidity rate of the air, have, in the valleys, dramatic effects. So the choice of the place where to plant a vine, and the choice of the variety, is extremely important to have a good ripening and avoid frost damage.
Aosta Valley (Valle d’Aosta)
In the high Aosta Valley, North West of Italy, there is a small “enclave” of viticulture at the foot of Monte Bianco (White Mountain), the highest peak in the continent (4880 mt.), where vineyards are cultivated up to 1200 metres thanks to a particular mesoclimate. This climate is due to a paleoglacial small valley (Valdigne), that is a heat trap, and to a grape with a very short vegetative cycle: the Blanc de Morgex (or Prié blanc). From these vineyards, mostly overhead trellised to escape spring frost, one can enjoy a close, almost unbelievable view of some of the biggest and more majestic glaciers in the Alps. The white wine, obtained from these grapes, (Blanc de Morgex) has, ususallly, about 11 degrees of alcohol, a remarkable acidity, a delicate scent of honey and hawthorn flowers. In the best vintages it can age in bottle for some years, acquiring a clear mineral hint. To conclude, it isn’t only an oenological curiosity, but a truly interesting wine.
At a lower altitude other autoctonous grapes are grown, they have black fruit and and higher thermic requirements, with differences among them, but usually higher than the Pinot Noir, which is one of the international varieties most spread in the Valley. Some of these grapes are widespread, like the Petit Rouge, others are now rare, but becoming more and more interesting for their potential quality, that is still little known. We are mean grapes such us Fumin, Mayolet, Cornalin (French pronounciation). These names sound French, because Aosta valley is a frontier Region, where people speak an old French-Provençal language, Patois. Lower in the valley, and in a Piemonte area bordering on Aosta Valley (Carema) they cultivate also Nebbiolo, named here Picotener. Actually this famous Italian variety is well grown in some Alpine zones, where the climate is particularly mild. Yet the best “mountain Nebbiolo” is to be found in Lombardia and exactly in Valtellina (see further).
alle d’Aosta, some climatic data
Different stations, average of several years
Winkler DD index 1000-1900
Huglin index 1500-2400
Global radiation 4300-4500 MJ/m2 year
Annual rainfall 500-700 mm
Mean year temperature 10,4, °C
Mean July temperature 20,5 °C
Mean January temperature - 0,3 °C
Continentality (Jackson) 19,2
Susa Valley and Chisone Valley
In Piemonte, these two Alpine valleys (which will host the winter Olympic games in 2006), are more western zones on the border between Italy and France. Here viticulture has almost disappeared as people abandoned the mountains in the XX century. If compared with Aosta Valley, these valleys are narrower and less suitable for agriculture owing to their orographic structure. But there are some affinities that are worth being considered. A common root for the dialect and for the traditional heritage of the bordering mountains, the presence of old communication ways, across Alpine passes between the Italian peninsula and continental Europe, the presence of rare autoctonous grapes, some of which are very interesting, like Chatus and Becouet. One could say that these bordering regions have preserved an extraordinary reserve of biodiversity that nowadays is the object of important studies for ampelographers. The secret probably lies in two factors: the exchange of seeds and cuttings between the ancient travellers of the two slopes of the Alps and the fact that, in these zones, viticulture is often practised for hobby and not for income, and therefore, as it always happens in these cases, it has a strong conservative character.
The “School of Torino”
Where the Susa valley spreads into the Padanian flat there is the city of Torino (Turin). The famous hill viticultural areas of Langhe (the home of Barolo and Barbaresco) and Monferrato (the home of the best Barbera wines) are less than one hour driving to South and East, while the Alp range is West and North of this old town, which was founded by the ancient Romans and was the first capital of Italy after the national unification in 1860. Torino is the seat of a University of Agriculture with a strong focus on viticulture and oenology, and the seat of the Grape Vine Centre (now a section of the Institute of Plant Virology) of the CNR (Consiglio Nazionale delle Ricerche). The contribution of this institute, and, in particular, of Anna Schneider and Franco Mannini to the ampelographic knowledge and to the selection of new clones is remarkable all over the world.
The stone terrace
On the Italian Alps and in other European zones, such as the Mosel valley in Germany and the high Douro valley in Portugal, mountaneers invented, centuries ago, a particular method of cultivation: the stone terrace. This method requires a high expenditure of energies, both for its carrying out and for its maintenance, and high skill, but minimizes the two main limitations due to the nature of the ground: the steep slopes and the scarse soil’s depth. It is necessary to build stone walls, without any cementation, that run along the level curves. To build them, mountaneers generally gather the local stones from the same slopes, or from near quarries. Between terraces, they obtain a strip of land, a kind of pocket full of earth, that increases the layer at disposal of the roots and limits the erosion. There are different ways to plant the rows between the terraces: one wall for each row, one wall for more rows, or, like in many old vineyards, short, top-to bottom oriented rows between the terraces. The surplus water drains away through the clefts in the stone walls and is collected into small canals, that are sometimes coated with stones too. The height of the walls and the distance from one another depend on the slant: the bigger the slant, the shorter the distance between the walls, and the higher the walls. In Valtellina only, we reckon the walls built in the past centuries, and still utilized, have a linear winding of about 2500 kilometres. If we could calculate the lenght of these terraces built all over Europe, we would obtain a value much higher than the lenght of the Great Chinese Wall!
The stone walls convey the heat of the sun, in summer days, to the upward ground: this effect is added to the one of the slant to speed up the vegetative cycle of the vine. In fact it has been estimated that, for instance, a southoward slant of 58% (which is possible in the Alpine viticulture) increases the sun radiation of more than 30 % if compared to a level land.
One of the most spectacular examples of “terrace viticulture” is the Mediterranean zone of “Cinque Terre”, in Liguria (N-W of the Italian peninsula), where terraces reach the cliffs, and the cliffs hang over small, old villages of fishermen and peasants, and a cobalt-blue sea. These vineyards are listed in the patrimony of humanity by UNESCO.
Terraces steal considerable surfaces from farming. A Valtellina wine-grower, Domenico Triacca, invented a trellis system that makes it possible a better exploiting of the light on the terraced slant. This method was later studied and better set up in Switzerland, at the experimental station of Changins, by Murisier and collaborators. It consists in a vertically divided canopy, as it is done in the Scott Henry and in the Smart-Dyson, where the slanting part of the foliage leans against a wire bracket and hangs over the stone wall. By this device, it is possible to obtain a significant increase in the production in the yeald per land surface, without worsening, and sometimes increasing its quality. Yet the transpiration increases for more leaves exposure, therefore the water supply may become a problem, without any irrigation. Mountain soils are usually shallow, pebby and strongly draining, also as a consequence of the slant. In many zones of Austria, Switzerland and Slovenia the summer rainfall is generally sufficient to avoid stress, but this doesn’t always happen on the Italian slope of the Alps. But on the Alps there is often a good availability of water all through the summer, owing to the melting of the snow at a high altitude.
North of the River
In Aosta Valley the river Dora Baltea, a tributary of the river Po, flows from East to West; in Valtellina the river Adda flows from West to East. On the northern slopes of these valley vines are largely grown, because the mesoclimate there is excellent. A someway similar situation is to be found in another famous “terroir” in Europe: the Rheingau (Germany). At lower altitude, but higher latitude, the river Rhine, flowing down from the Alps to the North Sea, traces a wide loop from East to West. In this case, the river flow is such as to influence the climate, as it happens with lakes and the sea, though in a less significant way. On the steep slants, on the right of the river, some of the most famous Riesling in the world are produced and there are some mythic places of European wines, like Schlöss Johannisberg and the Cistercian Abbey of Kloster Eberbach. In these territories, the rows of vines are generally planted along the direction of the slant, fron the top to the bottom of the valley.
Nebbiolo, one of the most famous Italian grapes, is very demanding: it gives the best enological results only in some surroundings. Sythetically, it needs a rather long summer, that allows a late ripening, it needs much light and a good thermic range between day and night in the period of its ripening. In Australia, a place like this is Margaret River, mostly the Southern part of the peninsula (in the summer: but the winter in M.R. is very different from that of the North of Italy!). Actually I tasted a very good Nebbiolo produced by Erl Happ from a vineyard in Karrydale. In Italy, one of the most suitable surroundings for Nebbiolo is an Alpine valley, Valtellina. The viticulture spreads on about 900 hectares, most between 300 and 500 mt., and as far as 650 metres of altitude. The soils are acid, with pH 4,5 to 5,5. This valley is nearly at the thermic limit for this grape, and this fact has two consequences. The first: a strong incidence of the effect of the year. The second: in the best vintages the wine reaches a great balance between strength and freshness. Here, for centuries, the vine growers have learned to produce mellower and more concentrated wines using a mild or strong withering of the grapes. By means of a partial drying of the grapes they produce the “Valtellina Superiore”, by means of total dried grapes the “Valtellina Sfursàt”.
According to the traditional method, grapes are withered in the shade, on straw hurdles, in garrets with big side openings, that let in the autumn cool breezes coming down in the night from the mountains to the bottom of the valley. Therefore for a “big vintage” it is necessary a very good climate, both in summer and in autumn: at least if the work is carried out in the traditional way, that is now more and more often integrated by a system of forced ventilation to limit the risk of undesired moulds.
The best grapes are obtained in the years when the month before the vintage is little rainy and with rather cold nights. The two parameters are connected because the thermic range is higher when the sky is cloudless. The oenologist Claudio Introini (Sertoli Salis winery) has proposed a bioclimatic index that he tested on different vintages and found a good correspondence with the quality of the wine. This index is calculated by subtracting the sum of the rain fallen in the thirty days before harvest (in mm) from the sum of the daily thermic ranges. It is a rather empiric method, but in Valtellina it has proved functional. The “five stars” vintages occur when this number is higher than 350 (1997, 2001, 2002): the poor vintages when it is less than 100 (‘92, ‘93, 2000). Few exceptions to this rule happened in the last 15 years, and I think this index can work also for other regions and grapes, with different numbers. Maybe the number of rainy days would be considered too.
Valtellina, some climatic data
Station of Sondrio, average of 13 years (1990-2003)
Annual rainfall 1023 mm
Mean year temperature 11,87 °C
Mean August temperature 22,66 °C (July 22,44)
Mean January temperature - 0,75 °C
Continentality (Jackson) 23,41
What the mountain wines taste like?
I don’t know if we can speak of a particular organoleptic character of mountain wines. Generally, these are the characters of the wines from a cool climate: then we speak of red wines with their freshness, their floral character and red fruits, like raspberry and strawberry, that prevail on the character of body, structure, concentration of colour, noble tannins and alcohol, typical of warmer climates. These wines may be far from some “international standard”, but are much appreciated in Europe and not only here. I recently took part in a tasting in Davis, California, and a red wine from Aosta Valley pleasantly surprised all the tasters. In the mountain, the strong radiation helps the vines to produce good quantities of stylbens and reveratrol, with the well known benefits for the health as they are protectors of arteries.
The cases I spoke about are only a few examples of the viticulture in the European mountains. The cultivated areas are small, and the production is moderate in comparison with the total European wine. The European mountains are nowadays much less inhabited and cultivated than in the past, though they have preserved some of their best vineyards. All over the continent, from Portugal in the West, to Georgia in the East (the latter is considerd the cradle of wine) viticulture has represented in history a difficult and noble challenge for mountain people, who, almost always, were poor people, for whom wine was a precious source of energy, and precious as well for its religious meaning: a privilege granted to those who had plots of land facing South, not too high and protected from frosty winds.
Luigi Mariani, Osvaldo Failla, University of Milan (climatic data of Valle d’Aosta)
Martino Salvetti, Fondazione Fojanini di Studi Superiori, Sondrio (climatic data of Valtellina)
Claudio Introini, Azienda vitivinicola Sertoli Salis, Tirano
Consorzio Tutela Vini Valtellina