An appellation is a geographical area recognized for a distinctive combination of soil, climate, and identifiable regional wine character. The word appellation comes from the French Appellation d'Origine Controlee laws, which are laws meant to ensure quality within specific regions of France. These same principles have been used to create American Viticultural Areas (AVA) in the United States.

Appellations

Calistoga Appellation (AVA)

Calistoga Climate: Warm to hot, depending upon time of year; lower humidity; summer temperatures peak to 90°F (32.2°C) and fall to low 50s°F (11°C), the result of marine air from the northwest; cool afternoon and evening breezes

Elevation: 300 to 1200 ft (92 to 370m)

Rainfall: 38 to 60 inches (96.5 to 150cm) annually

Soils: Almost completely of volcanic origin, soils range from rocky, stony loam on the hillsides, to gravelly or cobbly loams on the alluvial fans, to heavier clay-silt soils in the valley center areas  More Info.