Nine districts. One Quilt

Oak Knoll District is located in the southern end of central Napa Valley, California and was officially designated an American Viticultural Area in 2004. Known for its relatively cooler climate and long growing season, the Oak Knoll District is one of Napa Valley’s more renowned sub-appellations. Oak Knoll is one of Napa Valley’s flatter appellations and it enjoys primarily deep loam soils. Its location to the north of Napa city places it right in the path of the daily fog that creeps up from the Bay, making it one of the cooler AVAs. Because of this, many white grapes can be found here, along with pockets of Merlot, Cabernet Sauvignon and some old vine Zinfandel.

The center of the appellation is dominated by rich fluvial soils, which are deposited over time by the rivers meandering path and regular flooding. These deep fertile soils make for fruity and charming wines (no strict mountain tannins here!). Things get slightly more complicated in the west, where a small alluvial fan sits at the base of Mount Veeder; here the soil is more gravelly and the terrain slightly undulating. From a climatic perspective, the regular fog keeps the temperatures down, which means the wines tend to be among the more elegant and understated in Napa Valley.

Atlas Peak is located in Napa Valley, California, on the western slopes of the Vaca Range that separates Napa Valley and the Sacramento Valley. Atlas Peak is the most prominent peak in the area at 2663 feet elevation.

Atlas Peak is the most southern link in Napa Valley’s Vaca chain and it is one of the more austere looking mountains in the region. Though it is closer to the San Pablo Bay and therefore slightly cooler, it receives some of the lowest rainfall in Napa Valley, which is evident in its parched landscape. Viticulture has a long history here but remains a minority presence. Despite large vineyards such as Antica and Stagecoach, Atlas Peak is primarily dedicated to cattle and other agricultural pursuits.

The westward orientation of most vineyards on the Vaca Mountains also extends the amount of direct sunlight on the grapes. The soil of this AVA is volcanic and very porous which allows it to cool down quickly despite the increased sunlight. The area has a fairly significant diurnal temperature variation upwards of 30 °F (17 °C) between daytime and night. This contributes to the balance of acidity that grapes from Atlas Peak vineyards are known to have.

Oakville is located in the heart of Napa Valley. This means it experiences both the heat of the northern reaches and the cooling influence of the Bay’s fog and breezes. Because of this, of the Cabernet-centric valley floor appellations (St. Helena, Rutherford, Oakville), its wines, while ripe and powerful, tend to exhibit remarkable finesse and energy. Furthermore, in the western hillsides where the vines are sheltered from the afternoon sun, the wines tend to be more brooding and mineral rich, while those on the volcanic eastern hills that bask in the afternoon sun are dusty, sanguine, with dried fruit tones.

Oakville’s soils vary considerably. In the east they are rust-red and iron-rich with abundant volcanic material mixed into the gravel and loam. In the center of the valley, the soils are deeper, darker in hue and primarily loam-based. The western edge features the famous gravelly fans that include Martha’s Vineyard and To Kalon. Just above this bench, estates such as Harlan are perched on a mix of sedimentary and volcanic rocks and soils.

St. Helena’s northern location on the valley floor means that it experiences only occasional morning fogs; this makes for a fairly hot appellation and indeed sometimes St. Helena can be hotter than Calistoga. Because of this, Cabernet Sauvignon from St. Helena tends to be quite decadent, with higher alcohols due to the warmer temperatures of the region. One exception is the western benchland where some producers such as Spottswoode, Anomaly and Corison are able to make wines in a more elegant style due to the protection afforded by the nearby Mayacamas against the hot afternoon sun.

This AVA has an unusual shape, like an hourglass, as it encompasses the narrowest part of the valley. The northern half of the appellation is similar in feel and temperature to Calistoga, while the southern half is kin with Rutherford. The soils vary from gravelly loam in the west to volcanic in the east. The appellation is also unique in that it contains alluvial fans on both sides of the valley.

The Chiles Valley AVA is a sub-appellation of the Napa Valley AVA, located in the north central region of Napa County. It was originally recognized as an American Viticultural Appellation in 1999 following the petition filed by Mr. Volker Eisele, owner of Volker Eisele Vineyard and Winery.

Chiles Valley is located on the eastern side of the Vaca mountain range, far from what many would consider to be Napa Valley “proper.” It is a long, skinny, high-elevation valley that boasts more vineyards than wineries and enjoys primarily volcanic soils.

The valley of Chiles Valley is completely ringed by mountains so, while the elevation plays a cooling role, the valley’s architecture can sometimes act like an oven, trapping the hot air. And while it is hard to define the taste of Chiles Valley wines since much of the fruit is blended into larger Napa Valley cuvees, the few wines that do hail exclusively from Chiles Valley tend to be fully-flavored but with a notable elegance, due to the prolonged growing season created by the elevation.

The Calistoga AVA is the most northerly of the “valley floor” appellations and also the hottest. It is surrounded by mountains on three sides, except where it borders St. Helena to the south. Here the valley floor is higher than in the south, so the lowest elevation is around 300 feet (91m). The soils are primarily volcanic in origin and volcanic activity still abounds in the region – Calistoga first became famous for its mineral-rich hot springs. Indeed, it’s very name hearkens to this, Calistoga standing for “California Saratoga.”

Calistoga’s orientation – ringed by mountains and far away from the cooling influence of the San Pablo Bay, creates a hot environment that makes for some ripe, rich reds that are dark in color and deep in flavor. That said, there are cooler micro- climates where elegance is achieved, such as in the northeast canyons where alpine drafts flow down from the mountain, delaying ripening and helping to retain acidity. The Chalk Hill Gap to the west is also an important feature, as it allows some Pacific influence to penetrate.

Calistoga is located at the top of the Napa Valley and is one of the most geologically uniform of all the Napa Valley AVAs, featuring primarily volcanic soil. All of the Calistoga AVA lies above 300 feet above sea level and vineyards are planted as high as 1200 feet above sea level. Typically higher elevation corresponds with cooler night time temperatures allowing for more acid retention and more balanced wines.

“Overlooking the town of Saint Helena, CA, Howell Mountain AVA is a sub-appellation of the Napa Valley AVA and is located in the northeast side of Napa Valley near the town of Angwin. Howell Mountain AVA was established as an American Viticultural Area in 1983 and was the first sub-appellation within the greater Napa Valley AVA.

owell Mountain was the first mountainous nested appellation to be drawn and declared. It is also unique in that, unlike the other mountains which run down to connect with the valley floor appellations, the AVA’s southern boundary is 1,400 feet (427m) above sea level. This boundary was selected by the AVA’s founders because that was the elevation at which the fog crested. The thinking was that vines grown above this elevation would be dramatically dis- tinct from those grown beneath.

Tucked into the foothills of the Vaca Mountains, the Coombsville AVA is a Napa Valley Appellation known for its temperate climate directly east of the City of Napa and was officially designated as a Napa Valley sub-appelation 2011. Coombsville is Napa Valley’s newest nested appellation and remains one of the least visited. This is because it is composed primarily of vineyards with only the occasional winery. Coombsville spreads out to the west of the town of Napa and up the slopes of Mt. George. The vast majority of vineyards spread across a west-facing concave bowl formed through millenia of landslides. The soil is primarily volcanic in origin and proximity to the Bay keeps the area awash in fog and sea breezes. Historically, the region was associated with Pinot Noir and especially Chardonnay plantings but many admire the backbone of the region’s Cabernet Sauvignons.

Because of its proximity to the San Pablo Bay, Coombsville experiences cooler temperatures compared to AVAs further north, allowing winemakers to harvest grapes later and at more developed phenolic ripeness. Therefore, many wines from Coombsville show generous soft tannins and notes of dark black fruits such as blackberry and blackcurrant while retaining moderate alcohol and refreshing acidity.

Shaped like a horseshoe, the combination of unique landforms and large elevation differences gives the Coombsville Viticultural Area a fog-protected partial basin with high surrounding ridges which create climatically unique features, including precipitation and heat summation.

Los Carneros AVA is a American Viticultural Area that spans across parts of Napa Valley and Sonoma. Los Carneros is known for its relatively cooler temperatures due to the marine fog and breezes coming in off the San Pablo Bay. Carneros is unique among American appellations in that it spans both Napa and Sonoma counties; because of this, it is not technically a “nested” AVA of Napa Valley and the Napa part of the area is referred to as “Los Carneros.”

Carneros is composed of a series of low rolling hills that sit above the San Pablo Bay and beneath Mount Veeder. The soils are predominately sandy loam over clay. Because of the cooling influence of the Bay and regular fog and ocean breezes, Carneros is widely considered to be “Napa’s Burgundy,” as Pinot Noir and Chardonnay thrive here. That said, it might be more accurate to call it, “Napa’s Champagne” because multiple sparkling houses have set up shop here and produce truly world-class sparkling wine. Carneros has also been gaining attention recently for its Merlot, which loves the clay soils and excels in the warmer pockets of the region.

The relatively cooler climate of Los Carneros makes it suitable for varietals such as Chardonnay and Pinot Noir. Carneros may be cooler than Napa Valley proper but it is considerably warmer than the Sonoma Coast, so the Pinot Noirs tends to be comparatively ripe, round and rich with an intense core of cherry fruit. The Chardonnays can be both powerful and bright with pronounced minerality. Los Carneros AVA was officially recognized as an American Viticultural Area in 1983 and was the first AVA to be purely defined by climate characteristics instead of geographical characteristics.