•
If wines are to be produced for ageing (vintage), small berries have a larger specific skin area con-
taining polyphenols, tannins, aromas and all the substances that, in sufficient concentrations, ena-
ble the wine to evolve.
It is clear that, if grape berries are separate and have a larger specific surface (surface per unit of volu-
me), they receive more solar radiation and ripen more evenly, expressing all the aspects of the variety
and the land harmoniously in the wine, making it different to other wines. And this is the basic aim.
Vigour, plantation framework and root soil volume of a stock
The vigour of a plant is the strength of its vegetative activity. Technically, Mas Martinet defines the
vigour of a stock as “the weight of the word in the form of shoots that adult stock is capable of
producing during one vegetative cycle”. Vigour is expressed in grams. For example, stock may
have a vigour of 300 g or 1,400 g.
The vigour of dependent stock depends primarily on the variety of the vine, the fertility of the soil
and the climate.
The plantation framework (PF) is the area defined by the space between rows of stock forming
the service passageway or middle width and the distance between stock on the same row.
The root soil volume (RSV) is that available for the growth of stock roots without touching neigh-
bouring stock. The RSV is determined by the plantation framework and the depth at which the
roots are active, which may be 1 m.
c=1.2m
h=2.5m
PF
h (distance between rows of stock) = 2.5 m
c (distance between 2 consecutive stock on 1 row) = 1.2 m
PF (plantation framework) = hxc = 3 m
2
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It was also observed that the autochthonous varieties of Cariñena and Grenache on young vines plan-
ted in fertile land produced extremely compact bunches with very large berries that, once collected,
had a deficient level of even ripeness (berries still green with others over-ripe).
Moreover, old vines are known to produce a quality grape for two reasons:
•
The traumatic damage to the stock caused by yearly pruning prevents sap from passing and redu-
ces its vigour, thus leading to grapes with small, loose berries.
•
Plantations on steep slopes without terracing (“costers”) also reduce the vigour of the plant, given
that any fertile soil is dragged away by the rain. In this case, erosion is the case of lower, yet hig-
her quality production.
The problem is as follows: in new terraced plantations with fertile soil with no erosion and water reten-
tion for penetration, the stock expresses all its vigour and tends to produce very large, compact gra-
pes. Its berries no longer ripen at the same time and, as a result, the vine loses quality.
To date, the conventional solution given to this problem of quality consisted of “making the plant suffer”
to reduce its vigour: no irrigation, no tilling, less fertilisation, etc. In other words, vigour is dealt with
like a defect that must be corrected to obtain lower products of a higher quality, similar to that of old
vines.
However, the basis of the Mas Martinet technique is to consider vigour as a virtue of the plant - sho-
wing its good condition - not as a defect and trying to redirect it towards quality fertility. A large part
of the experiments carried out by Mas Martinet since 1997 have focused on optimising vigour mana-
gement of the autochthonous varieties in the new terraced plantations.
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3.2. Plant architecture
3.2.1 Shoot diameter
Mas Martinet therefore knew what the grapes should be like, although it was unaware how to obtain
these on young vines planted on terraces. Initial experiments based on leaving fewer bunches on the
stock or on reducing the distance between stock did not give the expected results: the grapes remai-
ned large and compact.
Finally, the hypothesis that experiments have proven to be true was posed: the morphology of the
grape is related to the diameter of its shoot. It was seen that shoots exceeding 10 mm in diameter pro-
duce compact grapes, but if the diameter is between 6 and 8 mm, the grape berries are small and
loose (Figure 3.2).
To ensure that the shoots were thin enough, a larger number of shoots were left on the stock so that
competition between them would lead to the required reduction in size. Where the vigour of the plant,
which is inherent to its characteristics and growing conditions, is distributed among few shoots, these
would be thick and long. However, where the same vigour or amount of wood is to be distributed
among a larger number of shoots, these will be thinner and shorter (Figure 3.3).
Figure 3.3 Competition among shoots
for the same vigour
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Figure 3.2 The morphology of the
grape is related to the diameter of
its shoot
Few shoots that are
thicker and longer
A lot of shoots that are thinner and shorter
SAME VIGOUR = SAME
WOOD QUANTITY
Compact Grenache grape
Loose Grenache grape
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Experiments at Mas Martinet estimated that the optimum shoot was between 6 and 8 mm in diame-
ter, around 1.2 m long and between 45 and 55 g. in weight.
3.2.2. Vine training
In “T” or “cordón royat” vine training with a distance between stock of 1.2 m, between 10 and 14 shoots
are normally left with an average distance of 8-10 cm between them. It is also necessary to leave a larger
number of shoots for the same plant vigour and, therefore, the production branch must be lengthened
without varying the plantation framework. To do so, Mas Martinet has developed two new forms of vine
training:
•
Vine training with double production branch or “double training”
Whereas the length of the production branch in cordon royat vine training is equal to the distance
between stock, in double vine training the length is doubled without modifying the distance bet-
ween stock. This vine training consists of tightened wires between two metal frames located every
5 or 6 vines, which means that it can only be used when the terrace area is basically straight.
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