North Coast - Sonoma County Flashcards
How many AVA’s and Winerys
18 AVA
425+ Winerys
An hour north of San Francisco and wedged between the Napa Valley and the Pacific Ocean, Sonoma County is one of America’s most important and highest quality wine regions, a place of great diversity, dynamism and resiliency. Famous for growing a wide range of grapes, from old-vine Zinfandel to Pinot Noir, it is blessed with a wide array of microclimates, soils and growing conditions, and as an agricultural region that also sustains other types of crops, is at the forefront of coping and adapting to issues around climate change.
CLIMATE
Dry, Mediterranean with coastal influence
Sonoma County represents an ideal climate for winegrapes, in addition to other types of agriculture from dairy to apples. Average temperatures during the May through September growing season range from the 70s to low 90s Fahrenheit (21° to 32° Celsius) during the day, with cool nighttime temperatures in the low 40s and 50s Fahrenheit (4° to 10° Celsius), allowing for enviable acid retention in the wines. As the grapes grow, morning coastal fog is common; frost and rainfall are rare.
Fog is among Sonoma County’s most defining features. The Russian River draws fog from the Pacific Ocean inland toward Healdsburg and the warmer Alexander Valley, impacting the 15,000 acres/6,070 hectares of vineyard within the Russian River Valley itself. Cool air also travels through the Petaluma Gap and San Pablo Bay to the south.
KEY VARIETIES
Chardonnay (27%),
Pinot Noir (23%),
Cabernet Sauvignon (22%),
Zinfandel (8%), and
Merlot (7%)
KEY SOIL TYPES
Eleven formation types; 31 different soil series including alluvial, volcanic, Goldridge, Franciscan and clay loam
Sub AVA’s
Alexander Valley
Bennett Valley
Chalk Hill
Dry Creek Valley
Fort Ross-Seaview
Fountaingrove District
Green Valley
Knights Valley
Los Carneros
Moon Mountain
Petaluma Gap
Pine Mountain-Cloverdale Peak
Rockpile
Russian River Valley
Sonoma Coast
Sonoma Mountain
Sonoma Valley
Alexander Valley
Topography/Elevation/Water Sources/Geographic Features
Elevations range from 100 to 2,572 feet/30 to 784 meters. High elevation sites receive more sunlight as coastal fog burns off earlier in the day. The valley rises on the east into benchland slopes where 80% of vineyards are located, clustered in the middle of the valley at the base of the Mayacamas Mountains. The mountains border the appellation to the east; the Russian River runs through it.
Geology/Soil Composition
Benchland soils are rocky and less fertile than the valley floor and well-drained, typically contributing lower yields. The soils are diverse, thanks to the area’s history of plate movements, featuring volcanic and sedimentary rock and rich in calcium, gravel, sand and clay content. Benchland soils are gravelly, sandy loam, primarily Yolo and Cortina, and well-drained due to slope and have calcium magnesium ratio for Cabernet Sauvignon.
Climate
Largely Mediterranean with wet, cool winters and warm, arid summers. Cooled from south to north by marine air that travels along the Russian River.
Main Grape Varieties
Cabernet Sauvignon, Chardonnay, Zinfandel
Chalk Hill
Topography/Elevation/Water Sources/Geographic Features
A meandering region that travels through hills and valleys, it reaches as high as 1,600 feet/488 meters in elevation.
Geology/Soil Composition
Mildly fertile, chalky white volcanic ash.
Climate
Warmer than the rest of the Russian River Valley as it is farther from the ocean’s cooling influence and largely above the fog.
Main Grape Varieties
Chardonnay, Cabernet Sauvignon
Dry Creek Valley
Topography/Elevation/Water Sources/Geographic Features
Fairly flat, Dry Creek is also marked by benchlands and hillsides along both sides of its fertile valley floor. Lake Sonoma lies at the northern tip of the AVA. The Russian River travels to the west of the region and heads south below Healdsburg, where it meets the Dry Creek.
Geology/Soil Composition
Created by the uplift and subsidence along earthquake faults and the deposit of alluvial material, Dry Creek’s valley soils are gravelly and sandy loam, deep, well-drained and fertile. Soils on the benches and hills are gravelly clay loam, rocky and red in color, draining exceptionally well.
Climate
On the northern edge of fog intrusion from the ocean, both coastal and inland influences exist here, with the coastal range to the west keeping cool marine temperatures at bay during long, warm days while serving as a conduit for coastal cold air and fog at night.
Main Grape Varieties
Zinfandel, Cabernet Sauvignon, Sauvignon Blanc
Green Valley
Topography/Elevation/Water Sources/Geographic Features
Fairly flat and heavily influenced by the Pacific Ocean, the Russian River travels just north of the town of Forestville on its way to meeting the ocean at Jenner.
Geology/Soil Composition
Once covered by shallow inland sea, Goldridge soils dominate here, a fine, sandy loam over fractured sandstone with excellent drainage and low fertility. Also, rocky Franciscan soils.
Climate
Exceptionally foggy, with lengthy cold temperatures. First place fog comes in and last place fog goes out. Coastal climate with narrow temperature swings. Lowest average summer temperature in Sonoma County.
Main Grape Varieties
Pinot Noir, Chardonnay
Fort Ross-Seaview
Topography/Elevation/Water Sources/Geographic Features
Buffeted by the ocean by Black Mountain to the west, this AVA is defined by steep elevation, lying largely above the fog line, from 920 to 1,800 feet/280 to 549 meters elevation. That height allows it to enjoy plenty of sunlight and heat during the growing season, despite its proximity to the coast. The area is rugged, widely sloped and forested.
Geology/Soil Composition
Defined by the San Andreas Fault and Pacific Ocean, the soils are diverse and derived from sedimentary rocks and deposits. Well-drained gravelly loam soils derived from sandstone and shale are common.
Climate
Heavy winter rainfall, moderate conditions during the growing season, with drier, warmer temperatures than many of the valley AVAs that sit in summertime fog.
Main Grape Varieties
Pinot Noir, Chardonnay
Knights Valley
Topography/Elevation/Water Sources/Geographic Features
The Mayacamas Mountains to the east and high-elevation Mount St. Helena protect the area from coastal influence, keeping it warm and dry.
Geology/Soil Composition
Rich, well-drained soils influenced by volcanic activity. Shallow, alluvial and gravelly, with volcanic ash and rock.
Climate
Warm afternoon and cool evenings are the norm, with the daytime temperatures during the growing season among the highest in Sonoma County.
Main Grape Varieties
Cabernet Sauvignon
Petaluma Gap
Topography/Elevation/Water Sources/Geographic Features
Mostly flat, there are a few high-elevation sites of note, including 1,400 feet/2,253 meters’ elevation Sun Chase and Gap’s Crown vineyards. Most sites are western-facing and sloped. The Sonoma Mountains buffer it to the east. The Petaluma River travels along Lakeville Highway to San Pablo Bay.
Geology/Soil Composition
Ashy tufa-like volcanic soils. Mineral-rich clay loam and sandy loam soils have gravelly river cobbles.
Climate
Heavy morning fog during the growing season and cooling wind in the afternoon. Temperatures consistently swing 40 to 50 degrees F (4 to 10 degrees C) in a day, with fog returning at night.
Main Grape Varieties
Pinot Noir, Chardonnay, Syrah
Russian River Valley
Topography/Elevation/Water Sources/Geographic Features
The Russian River brings in fog and coastal breezes, as does the Petaluma Gap in the coastal mountains. Most of the area is a low-lying plain with benchlands and hillsides scattered throughout.
Geology/Soil Composition
Goldridge loam predominantly, with volcanic, alluvial and sedimentary.
Climate
Huge diurnal swings of 30 to 40-degree F (4 to 10 degrees C) are not unusual during the growing season, marked by warm afternoons with cooler mornings and evening temperatures. The ocean plays a big role, cooling with morning and evening fog that in some parts of the AVA can sit all day long.
Main Grape Varieties
Pinot Noir, Chardonnay, Zinfandel
Sonoma Coast
Topography/Elevation/Water Sources/Geographic Features
Largely flat and near the Pacific Ocean, it is hugely influenced by the cooling winds and temperatures of the fog and wind that result. Some rolling hillsides and high elevations in inland ridges above the fog, where warmer temperatures and ample sunlight are more typical. The San Andreas Fault runs through much of the appellation.
Geology/Soil Composition
Highly diverse, from marine deposits to Goldridge.
Climate
Cold and windy with extended periods of fog during the growing season. Higher-elevation sites enjoy more sun exposure within a still cool-climate environment. Twice the annual rainfall of interior Sonoma.
Main Grape Varieties
Pinot Noir, Chardonnay
Zone 3 warm which AVA
Dry Creek Valley,
Alexandre Valley,
Knight’s Valley