Roots

The vine gives out a tap-root from seeds, i.e., a main root which descends deeply into the ground and sends out branches at different heights. Nevertheless, according to vine-growing practices, use is not made of the germination of seeds, as the vine reproduces by means of "estacas" or cuttings which are rooted in nurseries and transplanted to the vineyard. In this case, the root develops in stages from the bottom end of the cutting, although, after some years roots also come out of higher parts of the cutting.

The dimensions of the root system of vines, as in the case of other arborescent or shrub-like plants, depend on the characteristics of the soil in which they are planted, on the planting density, on the type of stock, on the characteristics of the variety and the cultivation method (ploughing, working, fertilization, etc.).

The type of soil is highly important for the shape and dimension of the root system of the vine. For a "royal frame" of 2 x 2 metres and a 20-year-old vine, we have found the following dimensions:

Soil type	Max. depth (metre)	Max.extension (radius in metres)	Max absorption (at depth)
Marl	1,15	1,87	0,45
Ferrous clay	1,29	1,42	0,66
Alluvial soils	1,97	0,87	0,87

The dimensions in alluvial soil refer to soils where the limestone crust has been broken, as is the case with present planting techniques. Formerly, the maximum depth of this soil would only be about 60 centimetres.

The planting density and frame have influence on the development of the root system. When the density is high, i.e., when there are other vines very near, the vine tends to send its roots very deep. On the other hand, when they are widely separated, after some years the roots spread and do not go very deep.

In marl soils, the roots can easily penetrate the cracks in sandstone-limestone and develop in a very irregular way, both in shape and depth. It is interesting to note that there are vines planted in rocks by means of a drill which perforates the soft rock as far as the stratum of loose soil. In this way, the vine seems to grow on the rock, but this only covers the non-absorbent part of the root. Underneath, the roots extend easily.