Manual of techniques for sustainable mountain viticulture Josep Lluís Pérez Verdú

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The ground layout of the terraces follows the level lines that are generally curved. Polygonal layouts

are avoided, as they give the vineyard an artificial look that stands out from its surroundings. This

criterion makes the use of conventional, straight vine training difficult or means that shorter sec-

tions have to be used. However, this is not a problem if the vigour control techniques indicated in

Chapter 3 are applied. 

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The line of mountain peaks (where the gradient changes), especially if steep, and its plant life are

respected and terraces are started several metres downhill. 

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The rocky outcrops and older trees, uniqueness, landscape value or representativeness of the agri-

cultural past of the estate are preserved in the terraced area to break up the continuity of the vine-

yard (green islands) and to provide a shaded area where workers can rest. In larger vineyards,

autochthonous trees may have to be specifically planted. If a large tree is incompatible with the

implementation of the vineyard, it may be worth replanting it elsewhere. The huts and other buil-

dings with a cultural or tourist value are also respected. 

Terraces measuring a constant 1.3 m in width; note

the constant lengthways gradient 

The terraces follow the level curves with no polygo-

nal shapes

The plant life on the peak is respected 

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The plant life of any banks of the gulleys or streams running alongside the vineyard and the plant

life on the border of the vineyard are also respected, not only for their contribution to the landscape

but because they retain the soil, act as a visual reference and maintain agroforestry biodiversity. 

On all accounts, the conservation of these areas is planned in advanced before the earthworks are started. 

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The area around the access paths to the estates and the path itself are also worth attention. As well

as connecting the vineyards or the crop-growing land, providing access to the estates and enabling

agricultural machinery to get around, paths are a privileged platform for observing the countryside,

from where the uniqueness and details of the region that are imperceptible from more distance obser-

vatories can be appreciated. Wherever compatible with agricultural use, paths are open and accessi-

ble for public use in order to find a meeting point between the wine culture and its landscapes and

society and to help form part of the network of infrastructures supporting wine tourism.

New access paths to estates have been opened within the framework of the Life-Priorat project.

Certain design criteria are considered particularly important: 

- Widths over 5 m are avoided. Where necessary, small, wider sections are built for heavy vehicles

to be able to pass each other.

- Slopes and borders are finished and protected from erosion using appropriate plant life. 

- Lengthways and sideways slopes are ensured good runoff. 

- Where necessary, soft paving is used that blends in with the countryside.

- The use of urban-type signposting is avoided.

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Single trees and green islands in the vineyard 

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2.2.2 Prevention of erosion and controlled run-off of rainwater

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The terraces are built on a constant 3% lengthways slope and a 4-5% sideways slope towards the

mountain. As a result, the vertical distance between terraces remains constant throughout.

To strictly respect this criterion, excavation machinery equipped with a laser level is be used, as

shown later on in this section. This involves precise building work that requires a person with spe-

cific training in driving the machine (the machines must be adapted to the mountain and not vice

versa). 

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All of the terraces drain off to side drainage channels. The terraces change the hydrological system

of the mountain. Water no longer runs over the different natural slopes of the land until it reaches

the water courses but is channelled along well-built terraces to concentrate at its end points, incre-

asing its erosive force. As a result, it is extremely important to plan the safe channelling of this

water to natural watercourses where it can cause no damage. Hence, all terraces must drain into

drainage channels built for this purpose with the greatest guarantees of resistance and stability.

The optimum solution will depend on the morphology and resistance of the mountain formation on

which the vineyard is located.

Terraces with a constant lengthways gradient and

width 

Slope finishing with a constant height by laser levelling 

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According to the experiment carried out in the Priorat region, drainage channels should be loca-

ted on the versants of the mountain (“costers”) where the rock is erosion-resistant. The concave

areas of the mountain (“comellars”) are avoided, where sediments are accumulated and the risk of

erosion is maximum: the water would drag along sediments to leave them wherever its speed

decreases, causing an overflow that would destroy the drain and part of the terraces and aggra-

date watercourses and infrastructures. It is true, however, that the channel could be excavated and

reinforced with some kind of covering, although this would be a useless, unnecessary and artificial

expense. Furthermore, it would mean that more fertile soil, a scarce resource in the area, would

have to be removed and, as can be seen later on in this Manual, the Mas Martinet cultivation tech-

niques mean that its entire value can be used. Therefore, despite sounding contradictory, the drai-

nage must be built on the slopes of the mountain where only a few centimetres have to be dug for

an erosion-resistant channel. 

Under no circumstances does a terrace drain onto another terrace. As already indicated, this prac-

tice has been seen to generate ridges at the reception point, where water is accumulated until it

acquires enough force to break the obstacle, causing a release of mud that has destructive effects

on lower terraces. Where rainfall is moderate, this severe erosion problem will not be generated,

although sediment may be accumulated, making the passing of machinery difficult. 

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The terrace length between two drainage channels is limited to 200 m to avoid erosion on the terra-

ce itself. Half of the terrace (100 m) drains towards one channel and the other half towards the

opposite channel. 

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Watercourses such as gulleys or streams are strictly respected. Under no circumstances are these

watercourses filled to build terraces. Quite the opposite in fact. Terrace drainage ensures that these

watercourses are reached without obstacles. 

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On terraces, the length of the slopes (I) with a gradient of over 25% is limited to a maximum of 6

m. For greater lengths, water has been seen to acquire excessive kinetic energy and may erode

the slope and accumulate sediment on the lower terrace, thus generating water accumulation and

machinery movement problems. However, this limit may vary according to the type of soil and the

extent to which the slope is protected, e.g. by plant cover. 

On gentle slopes, the maximum length does not depend on the risk of erosion but on the limita-

tions of the machinery to work on this slope from the terrace (e.g. for the application of treatments

to prevent stock disease), although this should never exceed 10-11 m.

Terraces with sideways drainage in erosion-resistant

area

The length of the slope may be greater when the gra-

dient is gentle and planting takes place on the slope

itself 

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