La zonazione della valle d’Illasi (Verona)

In the bottom of Val d’Illasi (Verona province), one of the major valleys which passes through the Lessini mountains, viticulture is widely extended. In the territory belonging to Illasi and Tregnago villages, which includes ca. 1100 ha of vineyards, devoted to produce Soave and Valpolicella DOC wines, an experimental survey was conducted on a network of twenty five reference vineyards. The area was characterized for soils, climate, viticulture and enological properties. The pedagogical survey carried out in the vineyards allowed to produce a soil map on a scale of 1:20.000 composed by 18 soil map units. In all the reference vineyards for three years (’93- ’95) grapevine phenology, yield, and vegetative growth were detected; during ripening maturation curves were monitored by juice composition. At vintage a sample of grape adequate for microvinification was collected. Wines were evaluated by sensorial analysis. The statistical data processing allowed to define 6 Land Suitability Units (2 for Soave and 4 for Valpolicella DOC), where vineyards resulted different in the vegetative and productive behavior, in the maturation patterns and in sensory properties of the wines. A satisfactory correlation among soil type x altitude interaction on phenology, vine potential yield and vegetative growth, grape and wine quality was able to explain the results, which were summarized in a Land Suitability map. Moreover, land characteristics and evaluation allowed to produce some Land Viticultural maps.