AVA stands for American Viticulture Area. The
BATF defines these areas at the request of wineries (followed by an opportunity for interested parties to comment) to define a geographical area which is entitled to carry the name of the AVA. Unlike most European
appellations, there are no additional requirements on which grapes may be grown, how they may be vinified, or how high the yield may be. As long as the wine meets the BATF's other requirements, it can be labeled with the AVA, assuming 85% or more of the wine in the bottle comes from the area defined by the AVA.
Politically defined areas such as California or Napa County are not AVAs, even though one frequently sees them used to identify the source of a wine. AVAs are reserved for situations where a geographically defined area has been using the name and it has come to be identified with that area. There are hundreds of AVAs, ranging in size from 26,000 square miles to less than a square mile.
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