The Geology of Calistoga Wine

Geologist David Howell lectures on the importance of geology to vineyard growers in the Jericho Canyon Vineyard.

Geologist David Howell (right) explains plate tectonics in the Jericho Canyon Vineyard. (BG)

A lot of factors go into the creation of an American Viticultural Area, better known as an AVA. An afternoon at Calistoga’s Jericho Canyon Vineyard with professor David Howell demonstrated the importance of geology in establishing terroir.

Designated in 2010 as a sub-AVA to the greater Napa Valley AVA, Calistoga is unique even within the California wine region. “Calistoga is self-contained,” said Howell, who is co-author of “The Winemaker’s Dance: Exploring Terroir in the Napa Valley” (Directors Circle Books). “It is a highly uniform, big bowl of volcanic soil.”

Howell elucidated for more than an hour. As I am neither a scientist, a winemaker nor a college student, I was overwhelmed by too much information. But I did learn a few things.

Although volcanism is more typically ascribed to areas east and north, such as the Cascade Range of the Pacific Northwest, it has a long and active history here as well. A range of volcanic peaks rose west of the Sierra Nevada beginning about 150 million years ago, Howell explained. It gave rise 3.6 million years ago to Mount St. Helena, which marks the north end of Calistoga.

As the Vaca Mountains (to the east) and Mayacamas Mountains (west) were squeezed by the San Andreas Fault, the V-shaped Calistoga valley — which opens to the southwest, at the very head of the Napa Valley — was formed less than a million years ago.

Unique terroir

What makes Calistoga special to wine producers?

With an average elevation of more than 500 feet, Calistoga is higher than other Napa districts. It has substantial rainfall: 37 inches annually at Jericho Canyon, nearly twice as much as the 20 inches received mid-valley at Yountville. Rain recharges aquifers and assures good water flow in volcanic rock.

Two kinds of fog — a valley fog and a moderating Pacific fog that flows in from Sonoma — help to mitigate Napa’s extremes of temperature fluctuation between day and night.

Perhaps most significantly, Calistoga is the only Napa AVA with 100 percent volcanic soil. Residual basaltic soil is mainly silica (including rhyolite), along with iron, magnesium and calcium. Alluvial soil fanned into the valley from historical floods as the Mayacamas was building up. These soils yield more nutrients, allow for better drainage, and concentrate flavor within berries instead of green growth.

Because there is great variation in aspect and slope within the AVA, the orientation of vineyards is key, Howell said. Some considerations: Is their gradient steep or gradual? Do vineyards face the morning or afternoon sun?

Cabernet sauvignons from Calistoga vineyards and wineries.

Cabernet sauvignons from Calistoga vineyards and wineries are universally outstanding. (JGA)

Cabernet sauvignon

The Calistoga AVA contains nearly 60 wineries. They are spread across 12,713 acres, of which only 602 acres are planted with vines. During my recent visit, courtesy of the Calistoga Wine Growers, I had occasion to enjoy tastes (and, in many cases, full bottles) from more than a dozen wineries.

2014 Bennett Lane cabernet sauvignon

2014 Bennett Lane cab sauv

Cabernet sauvignon was, by far, the most highlighted varietal.

The 2014 Napa Valley cabernet ($62) from Bennett Lane is elegant and structured, aged in 30% new French oak. You’ll likely pick up aromas of crème de cassis and raspberry on the nose, followed by cherry and chocolate on the palate. Alcohol by volume (ABV) is a heady 15.3%.

Davis Estates' 2014 cabernet sauvignon

Davis Estates’ 2014 cab sauv

The 2011 and 2012 cabernets (both $68) from Château de Vie, whose vineyards are side-by-side with those of Bennett Lane at the north end of the valley, are lighter and fruiter by comparison. I thought the 2011 is just now ready to drink, with flavors of blueberry, vanilla and fig to complement a rich cut of filet, while the 2012 could benefit from another year of aging. ABV 15.0%.

Davis Estates’ 2014 cabernet NV ($85), blended with 5% each merlot and petit verdot, balances aromas of currant, blackberry and cedar with flavors of berry and toasted oak. It’s a moderately tannic wine that will go well with red meats. ABV 14.6%.

Two cabernets came from the cave at Fairwinds Estate, deep in a hillside off the Silverado Trail. The 2013 estate cabernet ($75) has hints of cranberry with a touch of pepper and a lingering, sour cherry finish. ABV 14.5%. The 2012 Valley Floor cabernet ($95), from a premium mountain-flanked vineyard, has dense plum-and-licorice character and sweet tannins. ABV 14.1%.

More cabernets
2013 Tom Eddy cabernet sauvignon, Stagecoach Vineyard

2013 Tom Eddy Stagecoach cab

The Grade takes its name from “The Silverado Squatters” by Robert Louis Stevenson, in which the author describes a steep wagon route climbing Mount St. Helena, where he and his bride summered. Its 2013 Winfield Vineyard cabernet sauvignon ($99) shows floral, bell pepper and white pepper to balance intense blackberry and currant flavors. ABV 14.5%.

The 2014 Chris’s Cuvee cabernet ($65) from Kenefick Ranch earned 93 points from Wine Advocate. Aged 18 months in new French oak, then bottled unfiltered, it is rich with chocolate and

2012 von Strasser cabernet sauvignon from Vineyard 2131

2012 von Strasser V-2131 cab

blackberry flavors. Retired neurosurgeon Tom Kenefick has nurtured his vineyards for three decades. ABV 14.9%.

I’m a particular fan of the family-owned Tom Eddy Winery and its reserve cabernets. The 2012 Kerry’s Vineyard cabernet ($175) has a beguiling floral bouquet that overlays aromas of cedar and vanilla, followed by velvety soft tannins. ABV 14.4%. The 2013 Stagecoach Vineyard cabernet ($195) is a more masculine mountain wine showing hints of clove and pipe tobacco with bold tannins. ABV 14.7%.

The Von Strasser Family of Wines specializes in making only cabernet sauvignons and blends thereof. “I’m a big fan of blending because I think the wines become more interesting,” Rudy von Strasser told me. His 2012 Vineyard 2131 cabernet ($80), from a 3-acre bench on Diamond Mountain, incorporates a small amount of malbec to add to its depth of color, aroma and richness. ABV 14.2%.

Other Reds
The 2014 Canard Vineyard Adam's Blend, dominated by cabernet franc

Canard Vineyard’s 2014 Adam’s Blend

The Canard Vineyard, which produces eight separate estate varietals, also likes to blend its reds. The 2014 Adam’s Blend ($75) is 91% cabernet franc grapes, with 5% merlot and 4% cabernet sauvignon. Aged in French oak, this medium-bodied vintage has notes of strawberry jam and cocoa. ABV 14.8%. The Rescuer ($75), also 2014, is built of 90% merlot grapes, 8% cabernet sauvignon and just 2% cabernet franc. This elegant wine shows star anise and dried sage on the nose, cinnamon and black berries on the smooth finish. ABV 14.9%.

I found Bennett Lane’s 2012 Maximus Red Feasting Wine ($48) to have great character and excellent value. A blend of 74% cabernet sauvignon and 18% syrah with 4% petite sirah, 2% malbec and 2% merlot, it earned a 90-point rating from Wine Enthusiast. Aromas of blueberry and cassis are followed by a blackberry and mocha palate, with an elegant, tannin-driven finish. ABV 14.5%.

Coquerel Family Wine Estates focuses on non-traditional wines that are more accessible price-wise, including tempranillo and petite sirah, sauvignon blanc and Verdelho. The 2014 tempranillo ($42), from the estate’s Walnut Wash Vineyard, is dark and earthy. Enhanced by malolactic fermentation, it has a soft finish that goes well with pastas and spicy food. ABV 14.5%.

White wines

Coquerel’s flagship wine is its 2016 Le Petit Coquerel Sauvignon Blanc ($22), aged eight months in stainless steel with a weekly

Coquerel Vineyard's 2016 Le Petit Coquerel sauvignon blanc

2016 Le Petit Coquerel sauv blanc

stirring of lees. Crisp and fresh, its subtle traces of kiwi, guava and grapefruit suggest a New Zealand style balanced by typical California grassiness. ABV 13.5%.

Kenefick Ranch also makes an outstanding 2016 Sauvignon Blanc ($24). Six-month barrel fermentation in neutral French oak gives it a character very different than Coquerel. You’ll find tropical fruit on the nose, citrus on the palate and a creamy finish. ABV 14.1%.

Because Rudy von Strasser specializes in cabernets, he purchased the subsidiary Lava Vine Winery in 2015 to focus on a dozen other varietals. I’m fond not only of the refreshing 2016 Gruner Veltliner ($30), but also the excellent 2016 Verdelho ($30), a pucker-worthy Portuguese grape and a perfect complement to spicy Asian foods. ABV 13.4%.

No one in Calistoga is better known for its chardonnays that Chateau Montelena (see accompanying story), but Davis Estates is giving the Barretts a run for their money. Davis’ 2015 Chardonnay ($45) is a beautiful pale-gold color, with aromas of green apple and cantaloupe that blend with a toasted oak palate. It’s barrel-aged 10 months in 50% new French oak. ABV 14.8%.

By the glass

These were wines that I only had an opportunity to taste by the glass:

There are only two small-production Bragg Vineyards, Mario’s and Padre’s. I enjoyed the smooth, full-bodied 2012 Padre’s Vineyard cabernet sauvignon ($75), barrel-aged in oak for three years.

Barlow Vineyards’ 2012 Barrouge blend ($55) has 76% cabernet sauvignon along with 11% merlot, 9% petit verdot and 4% cabernet franc. Dark berry flavors blend with hints of vanilla and cocoa.

Jericho Canyon, where Howell walked me through the vineyard, has its own family proprietary blend. Chimera ($110) is a made up of four Bordeaux varietals — cabernet sauvignon, merlot, cabernet franc and petit verdot. An outstanding and complex wine, it shows black currant, plum and anise on the nose, but earth and floral tones on the palate.

Also see: Calistoga Wines Hold Napa’s Winning Hand


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