Wine-making in South Tyrol is particularly intense: it often involves manual work, on steep terraces, with techniques that respect the environment. Thanks to the so-called "integrated viticulture", South Tyrolean farmers strengthen the natural defenses of the vineyards, protecting beneficial insects and supporting their spread. Strict yield limits and the constant conversion of the classic pergola into the modern wire structure (Guyot) have improved the quality of the grapes. 58% of South Tyrolean wines are produced with white grapes: Pinot Grigio, Gewürztraminer, Pinot Bianco and Chardonnay are the most common. In addition, Sauvignon, Müller Thurgau, Sylvaner, Kerner, Riesling and Veltliner are produced. As for the red grapes, in Alto Adige together with the two indigenous varieties of Schiava and Lagrein, all the other classic vines have been produced for over a hundred years: Pinot Noir, Merlot, Cabernet Sauvignon and Cabernet Franc. Almost 42% of the vineyard area is cultivated with red wine varieties.