VITICULTURAL AREA: Defines a legal grape-growing area distinguished by geographical features, climate, soil, elevation, history and other definable boundaries. Rules vary widely from region to region, and change often. In the United States, a wine must be 85 percent from grapes grown within the viticultural area to carry the appellation name. For varietal bottling, a minimum of 75 percent of that wine must be made from the designated grape variety. See also appellation d'origine.