Silver Oak's Return to Form

It's not often that a venerable 40-year-old winery suddenly makes one of its best wines, perhaps in decades. But that may be the case with Silver Oak and its 2010 Napa Valley Cabernet Sauvignon.

Silver Oak is often an easy wine to single out in a blind tasting. Its signature oak presence of dill, vanilla bean and coconut stands out. I felt pretty confident that the wine in the blind tasting flight of 2010s recently was Silver Oak, but something else struck me about the wine. It offered more richness, body and flavor than I usually find in Silver Oak Cabernet. It seemed like the winery had added a tier of complexity that wasn't present in prior vintages.

I asked winemaker Dan Baron about whether anything different had occurred with this wine and of course there is plenty, beginning in 2008 with a new winery, all new barrels, updated equipment such as temperature-controlled fermentors and a cleaner "microbiological plate," in Baron's words.

A year later the winery adopted modified berry sensory analysis. It is a berry-tasting protocol, said Baron, that rates various berry parameters on a scale of 1 (underripe) to 4 (ripe). "We added 5, just overripe, and 6, overripe, to account for California conditions," Baron said. "Essentially you pick on the ripeness of skins." This method emphasizes the importance of skin texture in the quality of red wine. "In the 2010 vintage, this approach to harvest decision-making resulted in fruit-forward wines with fine-grained mature tannins at relatively low alcohols," which is exactly what I found.

In 2009 Silver Oak brought in a master cooper and took full control of wood supply. It also upgraded equipment and began to work on a new barrel-toasting regime. "2010 was the first vintage where we used barrels under these new guidelines, so I believe oak character is more refined in the 2010 and continues to become more integrated in subsequent vintages," Baron said. It shows.

Moving forward, the winery began in 2011 focusing on more precise viticulture. Details include using plant-based measurements—sap flow, pre-dawn leaf water potential, shoot length elongation rates, mapping of trunk diameters and pruning weights—to decide when, where and how long to irrigate. "My perception is that the wines have more aromatic intensity, length and tannic maturity under this new farming regime," Baron said.

In 2012 the winery hired renowned Bordeaux enologist Jean-Claude Berrouet of Château Pétrus fame as winemaking consultant, primarily for Silver Oak's sister winery, Twomey, which makes Merlot. His presence, said Baron, has stimulated and focused the entire production team at Twomey and Silver Oak and imbued a sense of purpose and context for the team. In 2013 the winery renewed attention to vineyard and farming measures to make sure their aim of greater grape quality was being fulfilled.

Silver Oak also hired Nate Weis to be Baron's successor, purchased Sausal Winery and Vineyard in Alexander Valley, and became full owners of A&K Cooperage for barrel production. Next on the drawing board: a new winery in Alexander Valley, which is the largest source of Cabernet for Silver Oak, ahead of Napa.