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Napa Valley’s Oak Knoll District Celebrates Ten-Year Anniversary

Wine Country’s ‘Sweet Spot’ Going Strong

April 18, 2014

Napa, CA—Ten years ago on April 26, 2004 the Oak Knoll District of Napa Valley (OKD) received its official recognition as an American Viticultural Area (AVA) from the US Department of Treasury’s then-Bureau of Alcohol, Tobacco and Firearms. Though one of the very earliest winegrowing districts of the Napa Valley, what has been a place of historic success for the region’s wines today showcases innovative and progressive farm management that leads the industry and has earned the reputation as the valley’s “sweet spot.”

“Traditionally ten years is celebrated with gifts of tin or aluminum…we’re thinking wine. It’s time to pull some corks and raise a toast—and our growers and vintners will be doing just that throughout the remainder of the year,” said OKD Association Board President John Wilkinson of Wilkinson Family Vineyards. “This past decade has really brought the esteem of Oak Knoll District’s vineyards and wine front and center.”

The recognition of an AVA is based largely on its uniqueness of soils and geology, geography, climate and to a lesser degree its historical significance. The OKD is one of the oldest grape growing areas in Napa Valley beginning with Captain JW Osborne’s purchase of land three miles south of Yountville which he named Oak Knoll around 1850. His 1,600 acre farm was the first in the region to be planted with higher-quality classic vinifera varieties rather than the ubiquitous Mission varieties planted before. His fifty acre vineyard was the largest and arguably most prestigious in Napa Valley. The property was a model farm and ranked Best in California by the State Horticultural Society.

Historian Charles Sullivan writes that had he not been shot to death by a disgruntled former employee in 1863, Osborne might well have been known as the father of the Napa Valley fine wine industry. Later the district brought notice to Napa Valley as an ultra-premium wine region with its top-ranked wines at the 1888 state viticultural convention.

Defining Features of the OKD

The district’s soils are alluvial from the runoff of the Dry Creek drainage—the largest alluvial fan in the Napa Valley and the only one to drain from north to south. Its run begins near Oakville Grade, drains the canyon of Dry Creek from two very different bedrocks, the Great Valley formation and the Franciscan formation. This alluvium, along with sections of volcanic intrusion, creates some of the most complex soils in the region. Unlike Carneros to the south which is largely ancient sea floor, the soils range from gravelly to loam.

The climate is cooler than the upper valley, yet warmer than windswept Carneros. OKD has a very specific climate and has come to be known as the sweet spot for both Bordeaux varieties like Cabernet as well as cooler climate varieties like Pinot Noir and Chardonnay. Longer growing seasons than the rest of the valley are due to warmer, dryer winters and cooler growing seasons with more morning and evening fog that provide long fruit “hang time.” Winemakers prize this winning combination as it allows for bright fruit flavors with excellent, balanced acidity and structure.

The winning Chardonnays from the Judgment of Paris as well as the Gault Millau World Wine Olympics tastings were sourced from the OKD and these grapes have a long reputation for their elegant style. Year after year critically acclaimed Cabernet and Merlot are produced from OKD fruit.

Today in the OKD

Most of the district is contained within the Napa Valley Ag Preserve, America’s first ag land protection preserve that was established in 1968. OKD plays an integral role in ag preservation keeping the urban footprint of the City of Napa in check, curtailing sprawl. High-quality grapes for the area’s top wineries are the priority. Producers from Opus One, Caymus, Joseph Phelps, Beringer, Merryvale, Rombauer, Duckhorn, Whitehall Lane, HdV and scores more grow or buy grapes from the mostly small, family-owned growers. Wineries in the district include Trefethen Family, Monticello, Robert Biale, Blackbird, Matthiasson, Lewis, Laird, and Black Stallion among others.

The district leads in farming innovation with large tracts of land, some of the first enrolled, in the industry-leading Napa Green Certified Land Program. Today, the OKD is has more vineyard acreage than any other wholly-contained appellation of the Napa Valley. Of its 8,300 total acreage, nearly 4,200 are planted to wine grapes. There are more than 18 varieties planted making it one of the most diverse as well. Top varieties by acreage are Merlot (1,113 acres), Chardonnay (1108 acres), Cabernet Sauvignon (926 acres), Pinot Noir (291 acres), Syrah (166 acres), and Sauvignon Blanc (142 acres). Additionally, all the other classic Bordeaux-style red varieties are planted, as well as Riesling and Zinfandel.

The vintners and growers worked for many years to have the area recognized as the Oak Knoll District of Napa Valley after a lengthy challenge from an out-of-state winery named Oak Knoll. Here the 150-year history of the region played an important role in the eventual granting of the recognition. And so today, the OKD is a prestigious wine appellation true to its historical sense of place.

“I cannot believe how ten years have passed, or that it took nearly ten years previous to that to work through the challenges of keeping our historic place name intact, but here we are and I am delighted to see the district thriving.  The vineyards are better than ever, the wines are varied, distinctive and outstanding across the board.  It’s a great time to be in the OKD,” said Janet Trefethen of Trefethen Family Vineyards, founding OKD board member.

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