The Diamond Mountain District AVA is an

American Viticultural Area An American Viticultural Area (AVA) is a designated wine grape-growing region in the United States, providing an official appellation for the mutual benefit of wineries and consumers. Winemakers frequently want their consumers to know about t ...

located in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

Mayacamas Mountains The Mayacamas Mountains are located in northwestern California in the United States. The mountain range is part of the Northern Inner Coast Ranges, of the California Coast Ranges System. Geography The Mayacamas Mountains are located south of the ...

in the northwest portion of the

Napa Valley AVA Napa Valley is an American Viticultural Area (AVA) located in Napa County in California's Wine Country. It was established by the Bureau of Alcohol, Tobacco and Firearms (ATF) on January 27, 1981. Napa Valley is considered one of the premier ...

. The

appellation An appellation is a legally defined and protected geographical indication primarily used to identify where the grapes for a wine were grown, although other types of food often have appellations as well. Restrictions other than geographical bo ...

sits at a higher elevation than most of

Napa Valley Napa Valley is an American Viticultural Area (AVA) located in Napa County in California's Wine Country. It was established by the Bureau of Alcohol, Tobacco and Firearms (ATF) on January 27, 1981. Napa Valley is considered one of the premier ...

's wine region, resulting in less cool fog coming in from

San Pablo Bay San Pablo Bay is a tidal estuary that forms the northern extension of San Francisco Bay in the East Bay and North Bay regions of the San Francisco Bay Area in northern California. Most of the Bay is shallow; however, there is a deep wate ...

, and more direct exposure to

sunlight Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when ...

. The soil of this AVA is

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plat ...

and very

porous Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure ...

which allows it to cool down quickly despite the increased sunlight.

Geography and climate

The entire AVA is over above sea level, which helps to cool it compared to the nearby valley floor appellations. The soil of the Diamond Mountain District is volcanic, including the small bits of

volcanic glass Volcanic glass is the amorphous (uncrystallized) product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the closely packed, highly ordered array of a crystal and the highly disordered array of ...

that give the area its name. The AVA is defined by the Napa- Sonoma county line on the west, Petrified Forest Road on the north, the 400 foot line of altitude running parallel to Route 29 on the east, and the Spring Mountain District to the south. This puts the southern part of the city of

Calistoga, California Calistoga (Wappo: ''Nilektsonoma'') is a city in Napa County, in the Wine Country of California. Located in the North Bay region of the Bay Area, the city had a population of 5,228 as of the 2020 census. Calistoga was founded in 1868 when th ...

in the appellation, with the northern part being in the

Calistoga AVA The Calistoga AVA is an American Viticultural Area located in the northern portion of California's Napa Valley AVA. The appellation is distinguished by its volcanic soil, high temperatures up to during the day, and cool nights during the grow ...

since 2010.

History

Diamond Mountain District's history as a winegrowing region dates back to 1868, when the first vines were planted by Jacob Schram on a tract of land he purchased on the Napa side of the mountain. By 1892, his holdings had expanded to 100 acres, including underground cellars for aging and storing wine. His name has continued in the property, now known as

Schramsberg Vineyards Schramsberg Vineyards is a winery located in Calistoga, California in the Napa Valley region. The vineyard, which was founded in 1862 by the German immigrant Jacob Schram, produces a series of sparkling wines using the same method as champagne. ...

Controversy

When the AVA was proposed in 1999, a request for public comments was published in the Federal Register. One winery, Diamond Mountain Vineyards, objected to the western border ending on the Napa-Sonoma county line, as it would split their property in half. Their objections extended the public comment period by several months. Ultimately, the decision was to keep the boundary on the Napa-Sonoma line. Additionally, as originally proposed, the AVA would have been called the "Diamond Mountain AVA," but since the bulk of Diamond Mountain, and indeed, its peak, are in Sonoma County, the AVA was renamed.

References

External links

{{Coord missing, Napa County, California American Viticultural Areas of the San Francisco Bay Area Geography of Napa County, California American Viticultural Areas 2001 establishments in California