Black truffle (Tuber melanosporum Vitt.) obtention in a mycorrhized oak orchard of a traditional irrigated land The background, features and farming methodology to set up a Tuber melanosporum Vitt. mycorrhized oak orchard in order to harvest black truffle in Zaragoza (Ebro Valley, Spain), are described in this paper. Although truffle cropping is a common activity of diversification in mountain depressed areas the establishment on irrigated and calcareous soils could be considered in the same way as a fruit orchard. A first black truffle was obtained in an experimental plot of Agrifood Research and Technology Centre of Aragon, located in Zaragoza. This new event in this field supports this assertion in contrast with the orthodoxy of the current trends in truffle farming.