The black truffle and summer truffle growing areas have limestone soils, generally of a poor quality. These areas are used for crops associated with low agricultural performance. These farms depend on financial aid for their survival. Truffle growers do not have to depend on subsidies any more, as they can triple the income earned from traditional crops in these areas, and the value of farming land may even increase in truffle growing regions.
Spain, where it is estimated that some 10,000 families are involved in truffle growing and truffle gathering, accounts for 30-50% of world black truffle production. Very few people now work exclusively as truffle hunters. Most combine truffle hunting with other work and/or do it at the weekend, or try to match their holidays with the gathering season. A truffle hunter working a full day currently collects between 3-5 kg of wild black truffle a week, very far from the 8-12 kg a day remembered by old truffle hunters.
The price of black truffles in Spain varies greatly depending on whether the season is good (with plenty of truffles) or not. Truffle prices conform to traditional models, where higher production means lower prices. Truffle gatherers are paid between €200 and €850 per kg for the black truffle,197 and, generally, just under half this amount for winter truffles in the same season. The price paid to gatherers for the summer truffle in Spain is between €35 and €80 per kg.