The Chalk Hill 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 winery, wineries and consumers. Winemakers frequently want their consumers to know abo ...

(AVA) located in

Sonoma County Sonoma County () is a county (United States), county located in the U.S. state of California. As of the 2020 United States Census, its population was 488,863. Its county seat and largest city is Santa Rosa, California, Santa Rosa. It is to the n ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. The boundaries of the wine

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 boun ...

cover the northeast corner of the

Russian River Valley AVA The Russian River Valley AVA is an American Viticultural Area (AVA) in Sonoma County, California. Centered on the Russian River, the Russian River Valley AVA accounts for about one-sixth of the total planted vineyard acreage in Sonoma County. Th ...

. The majority of vineyards are located to the east of

U.S. Route 101 U.S. Route 101, or U.S. Highway 101 (US 101), is a north–south United States Numbered Highway that runs through the states of California, Oregon, and Washington, on the West Coast of the United States. It is also known as (The Royal Roa ...

, near the town of

Windsor Windsor may refer to: Places Australia * Windsor, New South Wales ** Municipality of Windsor, a former local government area * Windsor, Queensland, a suburb of Brisbane, Queensland **Shire of Windsor, a former local government authority around Wi ...

. The name Chalk Hill comes from the unique

volcanic soil The soil composition of vineyards is one of the most important viticultural considerations when planting grape vines. The soil supports the root structure of the vine and influences the drainage levels and amount of minerals and nutrients that the ...

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Chalk ...

y white

ash Ash or ashes are the solid remnants of fires. Specifically, ''ash'' refers to all non-aqueous, non- gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash ...

which has shown itself to perform well with planting of white wine

varietal A varietal wine is a wine made primarily from a single named grape variety, and which typically displays the name of that variety on the wine label.The American Heritage Dictionary of the English Language, Fourth Edition, 2000.winepros.com.au. ...

s like

Chardonnay Chardonnay (, , ) is a green-skinned grape variety used in the production of white wine. The variety originated in the Burgundy wine region of eastern French wine, France, but is now grown wherever wine is produced, from English wine, Englan ...

and

Sauvignon blanc is a green-skinned grape variety that originates from the Bordeaux region of France. The grape most likely gets its name from the French words ''sauvage'' ("wild") and ''blanc'' ("white") due to its early origins as an indigenous grape in ...

. The majority of the region's wineries are located on the western slopes of the

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 ...

Geography and climate

The boundaries of the Chalk Hill AVA cover of land within the northeast corner of Russian River AVA. Many of the region's of planted vineyard land is located along the western slopes of the Mayacamas Mountain reaching up to

altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...

s of 200–1300 feet (60–400 meters). Compared to the rest of the

Russian River Valley The Russian River (Southern Pomo language, Southern Pomo: ''Ashokawna'', es, Río Ruso) is a southward-flowing river that drains of Sonoma County, California, Sonoma and Mendocino County, California, Mendocino counties in Northern California. ...

, the Chalk Hill region is relatively warm due to the influence of a thermal belt that runs through the area.

Harvest time Harvesting is the process of gathering a ripe crop from the field (agriculture), fields. Reaping is the cutting of grain or pulse (legume), pulse for harvest, typically using a scythe, sickle, or reaper. On smaller farms with minimal mechaniz ...

often takes place in September while harvest in the surrounding regions usually takes place in October.T. Stevenson, ed. ''The Sotheby's Wine Encyclopedia (4th Edition)'' pg 482 Dorling Kindersley 2005 The area takes its name from the "chalky" white soils of the region. However the soils themselves do not contain any chalk but rather are composed of a mixture of

quartzite Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tect ...

abundant volcanic ash,

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...

and

silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel when ...

loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–sil ...

. The volcanic was emitted into the area by Mount St. Helena over a course of centuries, creating

vineyard soils The soil composition of vineyards is one of the most important viticultural considerations when planting grape vines. The soil supports the root structure of the vine and influences the drainage levels and amount of minerals and nutrients that the ...

that are not very

fertile Fertility is the capability to produce offspring through reproduction following the onset of sexual maturity. The fertility rate is the average number of children born by a female during her lifetime and is quantified demographically. Fertilit ...

and are able to restrain vigor in the vines.

References

External links

Sonoma County Winegrape Commission appellation maps
{{Coord, 38.56, -122.77, scale:10000_region:US-CA_type:adm3rd, display=title American Viticultural Areas American Viticultural Areas of California American Viticultural Areas of the San Francisco Bay Area Geography of Sonoma County, California 1983 establishments in California