In the triumvirate of North Coast counties, Sonoma stands out for its diversity of vineyard locations and grape varieties. Within the broad east-west expanse, bounded by the moderating Pacific Ocean and a range of low mountains, Sonoma County is a land of unlimited potential for grape growing and winemaking.
Long before vineyards covered much of the land, what we now know as Sonoma County was an inland sea. Violent tectonic upheavals of the coastal plates created present day Mayacamas Mountains that form the eastern boundary of the county. In sharp contrast are the southern rolling hills of Sonoma Carneros, once grazing land for sheep but now highly praised land for grape vines, and the slightly higher coastal hills that run the length of the county’s western edge.
Sonoma is the sleeping giant, offering a far more expansive and variety of wine types than any other California region. Though already believed to be amongst the finest, we believe Sonoma is still budding and will take its place amongst the most recognized premium regions in the world. Nowhere can you sip elegant Pinot Noirs of Russian River, smell the white pepper spice of Dry Creek Zins or stare into the depths of a ruby Alexander Valley Merlot or Cabernet Sauvignon…all within a 10 minute drive of each.
Pine Mountain-Cloverdale Peak
As part of the ancient Mayacamas Mountains, stretching from mid-Sonoma County north to the Mendocino border, Alexander Valley embodies all the unique quality aspects we look for in crafting a prestige wine. We were so impressed with this lesser-known region, we chose it to define the flagship wines of Ispiri.
Effective November 28, 2011, Pine Mountain-Cloverdale Peak became Sonoma County’s 14th AVA (American Viticultural Area). On the western slopes of the Mayacamas Mountain range, the AVA rises steeply over the Alexander Valley and Russian River and consists of 4,600 total acres—with only 5% of the slopes planted to vineyard. The vineyards on Pine Mountain are among the highest, if not the highest, in Northern California sitting above the fog line at 1,600 ft and climbing up to 3,000 ft. The boundaries of the appellation also encompass portions of both Sonoma and Mendocino Counties, another unusual feature.
Based on a rich history of viticulture, these small, high elevation vineyards are intensely farmed on red rock soils with mostly southwestern row orientations. The rugged terrain and steep hillsides require costly and extreme farming techniques, but the result is grapes which are highly sought by premium winemakers. The low vigor vines produce small sized, loosely packed clusters with tiny berries creating wines with unique textures and flavors from this distinct microclimate. Greater diurnal temperature fluctuations during the growing season, with extremely warm days and cool to cold nighttime temperatures, create bold and concentrated flavor profiles in grapes. Above the fog, and closer to the sun, with all its glory, Pine Mountain-Cloverdale Peak truly is a sleeping giant just waiting to be awakened.
Wine News—June/July 2004 Cover Story
Moving Up the Mayacamas Growing Mountain Cabernets of Stature and Distinction
“A certain mystique shrouds these lofty sites: Why are wines made from mountain-grown grapes so intense, flavorful and distinctive? The experts offer a variety of theories. Some think the soil is the main reason for the distinguishing attributes of the grapes. Others say it’s the elevation, which exposes the vines and grapes to the atmosphere in ways that better promote ripening, flavor intensity and balance. High enough up the mountain, increased levels of ultraviolet light exposure come into play which, some growers argue, increase the level of phenolics in the grapes (and therefore color) in the resulting red wines.
While enologists may debate infinite variations on these themes, the distinctions all come down to terroir—that total interaction of climate, soil and exposure that make up a specific site.
Despite the intangibles, more is known about mountain vineyards than that which remains unanswered: The soils are typically thinner, more acidic (as a consequence of higher rainfall) and shallower, resulting in a self-limiting environment that naturally moderates yield. Spring comes later, and the afternoons are cooler. The sun shines longer and with greater intensity. All of these factors combine to help produce a concentrated wine of distinctive character.”
The area that has been referred to as Rockpile since the 1850s was finally recognized as Sonoma County’s 12th AVA, effective April 2002. Located in Northern Sonoma County, at the northwest corner of Dry Creek Valley, the Rockpile AVA encompasses nearly 15,400 acres, of which less than 160 are planted to vineyard. This makes Rockpile one of the smallest AVAs in the United States in terms of acreage planted. Approximately 2,500 of the acres of the Rockpile AVA overlap the Dry Creek Valley viticulture area to the Southeast. Vineyards range in elevation from 800 feet to nearly 2,100 feet
The predominant geographic highlight is that all vineyards must be at 800 feet elevation and above to qualify. This elevation requirement also serves as the appellation boundary to the East as well as the North. Though it falls into the geographic category, it also greatly affects the geology and climate. There are certain aspects that are true of all elevation delineated AVAs; poor soils, steep slopes, little water retention and great sun and wind exposures. With Rockpile these aspects are exaggerated due to the lack of fog. The lack of fog increases the amount of sun exposure, but decreases the amount of moisture available to the vines. The lack of moisture leads to smaller berries, loose bunches, little to no bunch rot or botrytis, and over all outstanding fruit.
The Petaluma Gap, Sonoma Coast
The Petaluma Gap is the southern gateway to the Sonoma Coast region. Although, it is not yet an officially recognized appellation, the Petaluma Gap has a 150 year tradition of producing premium grapes that make the Sonoma Coast Appellation one of California’s best areas to grow primarily, Pinot Noir, Chardonnay and Syrah grapes. The wind and the fog are the Petaluma Gap's trademark. The “Gap” is actually a Wind Gap named after a coastal mountain opening that stretches from the Pacific-east through the town of Petaluma and then roars south to San Pablo Bay. This cooling “wind tunnel” effect results in smaller yields in the vineyards with later ripening grapes that posses wonderful flavors and fruit characteristics, while maintaining ideal levels of acidity. It’s the perfect recipe for intense but well-balanced wines.