62 Port anD the Douro
The ‘A’ grade vineyards are almost all located deep in the Douro valley and its tributaries
upstream from Covelinhas, with properties rated ‘B’ to be found at slightly higher altitudes.
Many of the ‘C’ grade vineyards are situated around Régua or on the high ground north
and south of the river. Vineyards categorised as ‘D’ and below are either in the westernmost
part of the region downstream from Régua or on the planaltos around Vila Real, Murça,
Meda and Lamego.
the BeneFíCio
The vineyard classification is the basis for the benefício or licensing system that determines
the amount of Port that may be produced in any one year. Taking into account the previous
year’s sales and stocks of Port held by the trade, the Oporto-based Instituto dos Vinhos do
Porto e do Douro (Port and Douro Wine Institute or IVDP) regulates the total amount of
grape must that may be fortified to make Port. The total amount of benefício (measured in
pipes of grape must of 550 litres) from 2001 to 2011 is shown in Appendix II.
Since 2003, the task of apportioning the benefício between the 34,000 growers has been
undertaken by the IVDP. With its head office in Oporto and a branch in Régua, the IVDP
is a public body representing growers, wine producers and shippers. Amongst its many
functions, the IVDP has now assumed overall responsibility for regulating the benefício via
the communicado da vindima or vintage communiqué, which is issued to growers in August
before each harvest. Using the cadastro or register compiled by the Casa do Douro, the
benefício is awarded to growers on the basis of their vineyard classifi cation (above). For
example, in 2011 an A-grade vineyard was authorised to produce 1,560 litres per hectare of
must for fortification, whereas an F-grade vineyard could fortify 523 litres per hectare. Any
vineyard with a classification below F had no entitlement to produce Port.
Further information on the responsibilities of the official bodies that regulate and
promote Port can be found in Appendix I.
vineyarD layout
Planning and planting a new mechanised vineyard in the Douro is as intricate as building a
new town. Access, gradients, drainage and density all have to be considered in detail if the
property is to function efficiently over a commercial life of fifty or more years. Over the past
four centuries, the slopes of the Douro have been sculptured into various shapes and forms
according to economic circumstances. The feature that all these methods of cultivation have
in common is the initial deep ploughing or ripping of the earth to create a coarse topsoil
roughly 1 to 1.3 metres in depth.
The earliest commercial vineyards in the Douro were planted on narrow, step-like terraces
supported by retaining dry-stone walls built to a height of between one and two metres (see
figure 1a). On the steepest slopes (with gradients of up to 70 per cent) these traditional
terraces, known as socalcos, support no more than a single row of vines planted at a density