Chalk Hill AVA
Encyclopedia
The Chalk Hill AVA is an American Viticultural Area
(AVA) located in Sonoma County, California. The boundaries of the wine appellation
cover the northeast corner of the Russian River Valley AVA
. The majority of vineyards are located to the east of U.S. Route 101, near the town of Windsor
. The name Chalk Hill comes from the unique volcanic soil of chalk
y white ash
which has shown itself to perform well with planting of white wine varietal
s like Chardonnay
and Sauvignon Blanc
. The majority of the region's wineries are located on the western slopes of the Mayacamas Mountains.
s of 200-1300 feet (60-400 meters). Compared to the rest of the Russian River Valley, the Chalk Hill region is relatively warm due to the influence of a thermal belt that runs through the area. Harvest time often takes place in September while harvest in the surrounding regions usually takes place in October.
The area takes it 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
abundant volcanic ash, sand
and silt
y loam
. The volcanic was emitted into the area by Mount St. Helena over a course of centuries, creating vineyard soils that are not very fertile
and are able to restrain vigor in the vines.
American Viticultural Area
An American Viticultural Area is a designated wine grape-growing region in the United States distinguishable by geographic features, with boundaries defined by the Alcohol and Tobacco Tax and Trade Bureau , United States Department of the Treasury....
(AVA) located in Sonoma County, California. The boundaries of the wine appellation
Appellation
An appellation is a legally defined and protected geographical indication used to identify where the grapes for a wine were grown; other types of food often have appellations as well...
cover the northeast corner of the Russian River Valley AVA
Russian River Valley AVA
The Russian River Valley AVA is an American Viticultural Area in Sonoma County, California. Centered around the Russian River, the Russian River Valley AVA accounts for about one-sixth of the total planted vineyard acreage in Sonoma County. The appellation was granted AVA status in 1983 and...
. The majority of vineyards are located to the east of U.S. Route 101, near the town of Windsor
Windsor, California
Windsor is an incorporated town in Sonoma County, California, United States. The population was 26,801 as of the 2010 census.-Geography:Windsor is located on U.S. Route 101 in the Russian River valley, about southeast of Healdsburg, California....
. The name Chalk Hill comes from the unique volcanic soil of chalk
Chalk
Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....
y white ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...
which has shown itself to perform well with planting of white wine varietal
Varietal
"Varietal" describes wines made primarily from a single named grape variety, and which typically displays the name of that variety on the wine label. Examples of grape varieties commonly used in varietal wines are Cabernet Sauvignon, Chardonnay and Merlot...
s like Chardonnay
Chardonnay
Chardonnay is a green-skinned grape variety used to make white wine. It is originated from the Burgundy wine region of eastern France but is now grown wherever wine is produced, from England to New Zealand...
and Sauvignon Blanc
Sauvignon blanc
Sauvignon Blanc is a green-skinned grape variety which originates from the Bordeaux region of France. The grape most likely gets its name from the French word sauvage and blanc due to its early origins as an indigenous grape in South West France., a possible descendant of savagnin...
. The majority of the region's wineries are located on the western slopes of the Mayacamas Mountains.
Geography and climate
The boundaries of the Chalk Hill AVA cover 33 square miles (85.5 km²) of land within the northeast corner of Russian River AVA. Many of the region's 1600 acres (647.5 ha) of planted vineyard land is located along the western slopes of the Mayacamas Mountain reaching up to altitudeAltitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
s of 200-1300 feet (60-400 meters). Compared to the rest of the Russian River Valley, the Chalk Hill region is relatively warm due to the influence of a thermal belt that runs through the area. Harvest time often takes place in September while harvest in the surrounding regions usually takes place in October.
The area takes it 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
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...
abundant volcanic ash, sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
and silt
Silt
Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...
y loam
Loam
Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...
. The volcanic was emitted into the area by Mount St. Helena over a course of centuries, creating vineyard soils that are not very fertile
Fertile
The term fertile describes a condition whereby organisms are able to produce physically healthy offspring.Fertile may also refer to:...
and are able to restrain vigor in the vines.