Manual of techniques for sustainable mountain viticulture Josep Lluís Pérez Verdú

The landscape and hydrological conditioning factors mean that mountain soil is a scarce resource

that must be used productively. As can be seen later on in the Manual (Section 4.1), the techni-

ques developed in Life Priorat provide the same grape production as with conventional techniques,

but using a much smaller area of land. 

2.1.2 Vineyard operation problems

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Occupational risk

In some plantations, the roads to the terraces are too steep because they are laid out perpendicu-

lar to the level lines. This involves a labour-related risk with regards to machinery traffic. The risk

is maximised on the bends accessing the terraces, particularly when driving a tractor and a trailer. 

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Reduced labour productivity

The natural slope of the land is often variable along the level lines. A solution sometimes applied

to prevent terraces with steep slopes from being built, which would make work difficult and wor-

sen erosion problems, involves increasing the width of the terrace. A variable width must be used

by planting a higher number of rows of stock, which leads to unproductive routes and complica-

ted manoeuvres to access all the vines. 

Another solution applied to avoid this problem is to build intermediate terraces that end up drai-

ning off into other terraces, generating the erosion problems already indicated. 

Moreover, work cannot be comfortable carried out behind the inner row of stock (e.g. for slope

maintenance work) that also tend to aggradate to some extent due to slope erosion. 

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Heterogeneous soil fertility

When the land is built using the conventional technique of cutting the top of the mountain and

filling the bottom part, the inner row of stock is planted directly on a compact substrate without

the top layer of soil, whereas the outer row (valley side) is planted on turned over soil. This means

that fertility cannot be homogeneous. 

Occupational risk: perpendicular accesses to

level lines with an excessively steep gradient 

Difficult to optimise cultivation work due to the

varying width of the terraces 

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2.2. Sustainable terracing techniques

The experiment carried out by Mas Martinet shows that the environmental and operative problems of

conventional terraces can be overcome through the application of appropriate design criteria. This

section describes the main criteria developed that have given good results in the Priorat region. 

Figure 2.2 shows the different variables involved in the design of terraces:

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For a given normal slope (α), the terrace is defined by establishing any two of the remaining para-

meters. For example, if the width of the terrace (a) is established, on decreasing the slope (β) gra-

dient, the height between terraces (h) increases. However, if the width of the terrace (a) is reduced,

the slope (β) gradient can be decreased without increasing its height (h).

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The slope gradient (β) is always greater than the natural gradient of the hillside (α).

Manual of techniques for sustainable mountain viticultur

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p

l

h

a

β

α

α

: natural slope gradient (% or º)

β

: slope gradient (% or º)

a: terrace width (m)

h: slope height (height between terraces) (m)

l: slope length (m)

p: horizontal slope ledge (m)

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2.2.1 Blending of terraces into the countryside

The basic design criterion is for the terrace-vineyard as a whole to adapt as much as possible to the

natural morphology of the land, minimising land movements and introducing no artificial forms that

could grossly stand out from their surroundings. 

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In general, the height of the slopes (h) is limited to 1.5 m.

This criterion is basic so that aggradation does not disturb the harmony of the landscape. For grea-

ter slope heights, terracing becomes extremely visible and stands out from its surroundings, giving

the vineyard the aspect of a quarry and the greater the high of the slope, the more noticeable it

becomes. 

In any terracing, the stock can be plated on the terrace or on the slope. When the vine is planted

on the slope, the limitation of its height may be somewhat more flexible, as the plant life will help

the slope blend into the surroundings. However, it is wise not to exceed slope heights of 2 m in

any case.

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The width of the terraces (a) must be limited according to the natural gradient of the land, so that

the above criterion is respected at all times, i.e. the slope height does not exceed 1.5 m.

Where small modern machinery is used, the terrace width may be as little as only 1.3 m. This is

the terrace width preferred by Mas Martinet and the only one used currently in its plantations (the

may reach 1.5 m in width in some cases). It only allows for one row of stock to be planted per terra-

ce and requires the building of a greater number of terraces than those used were the width to

accept two or more rows of stock, making the work more expensive. To compensate for this, the

height of the slope is lower and the area can be adapted much more easily to the mountain mor-

phology. A single row of stock on the outer part of the terrace also has advantages regarding the

landscape, given that the eye of a distant observer follows the ends of the stock in a straight line,

without it being broken by other rows of stock located on the inner part of the terrace. This also

makes access to the slope easier for maintenance purposes. 

Both this and the previous criterion are completely incompatible with the construction of large leve-

lled areas for the reproduction of flat-land vines, particularly on steep natural slopes. 

Natural land with a gradient of over 60%. The slo-

pes do not exceed 2 m in height; slope plantation 

Centre left is a plantation on a terrace, with slopes

measuring over 1.5 m in height. The appearance

of the lower three terraces improves as the slope

height decreases. On the right of the photo is a

plantation on a slope that blend in very well with

the landscape, as terracing is almost impercepti-

ble

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