The property lies within the larger Napa Valley AVA, American Viticultural Area, or appellation. The Napa Valley AVA encompasses the entire 300,000 acres of Napa County. Approximately ten percent of this land is utilized as vineyards. Within the Napa Valley Viticultural Area and its 240 wineries, the microclimates are distinctive and dramatic. Due to these differences, the Napa Valley AVA has been further subdivided into fourteen sub-appellations. Under this refined classification scheme, this property is located within the Chiles Valley sub-appellation. For labeling purposes, wines produced from at least 85% of grapes grown in this AVA can print the Napa Valley or the Chiles Valley appellation name on their labels.

Located 800 to 1000 feet above sea level, the Chiles Valley appellation runs northwest to southeast, creating an open funnel for northwesternly winds. This fairly constant northwesternly flow produces substantial cooling during the day and, in combination with the altitude, relatively dry air. The afternoon breeze that comes off the slope of the mountain minimizes the threat of mold and mildew to the grapes. During the night, this drier air leads to more rapid cooling than most areas of Napa Valley. In addition, the narrow valley is surrounded by hills up to 2200 feet which concentrate the cooler air flowing down the hillsides toward the valley floor where the vineyards are located. Also the relative distance from San Pablo Bay and the Pacific Ocean allows summer fog to move in much later than in the main Napa Valley, thereby causing much lower temperatures during the night. Late fog ceiling, combined with low minimums, cause a slow heat buildup during the day, again producing relatively cooler temperatures than those found in many places in the Napa Valley, creating an optimal environment for high quality grapes.

For additional information on the Chiles Valley appellation please refer to www.wineinstitute.org/industry/ava/reference/fr/htm/chiles_valley_final.htm.