Guenoc Valley AVA Semillon, Sauvignon blanc and Chardonnay, as well as Malbec and Petite Sirah from the estate vineyards. Petite Sirah is the leading red grape in the appellation, followed by Cabernet Sauvignon, Merlot, Petit Verdot, Carmenère, Cabernet Franc and Malbec. Among whites, Langtry grows Chardonnay, Sauvignon blanc, Semillon, Marsanne and Viognier. Langtry also has the distinction of having some of the oldest vines in California, as a couple of Syrah vines dating back to the 1850s still grow at the Tephra Ridge Vineyard. Guenoc Valley AVA The Guenoc Valley AVA is an American Viticultural Area in Lake County, California, United States, about
Peloursin Rif" (later Durif) by ampelographer Victor Pulliat in 1868. Durif later made its way to California where it was eventually named Petite Sirah. In the late 20th century University of California, Davis researchers led by Dr. Carole Meredith discovered that some of the California plantings of Petite Sirah were, in fact Peloursin, and that Peloursin had a parent-offspring relationship with Durif that likely sprung from a crossing with Syrah. Peloursin is a vigorous grapevine capable of producing high yields and excessive foliage if not kept in check with winter pruning and summertime leaf pulling. The variety tends to be a