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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).
Valle
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
Aosta
station
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.
Valtellina
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.
Conclusions
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.
Acknowledgments:
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
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