In the traditional dry farming system (Spanish: año y ves,
cultivo al tercio) in the semi-arid parts of Spain, arable land
lies fallow as bare fallow for up to two years, is ploughed
several times for complete infiltration of precipitation, and is
harrowed and rolled after rainfall in order to minimise evap-
oration loss. With the water stored in the ground wheat or barley
can be grown in the second or third year. The EU Commission
responded to the overproduction of agricultural products (in the
European Union) with set-aside programmes. Consequently,
since the beginning of the nineties in the semi-arid parts of
Spain the number of abandoned fields has increased constantly
supported by subsidies up to 45% of all rainfed land (Marzolff
et al., 2003)