After 1976, when a chunky Napa cab from Stag's Leap Wine Cellars beat out Bordeaux wines in a French tasting, California producers went even richer in style. Vintners flooded the region, including a few French ones: Mouton-Roths-child partnered with American winemaker Robert Mondavi to open Opus One in 1979, and Chateau Petrus's Christian Moueix launched Dominus in 1983. A few years later, the discovery of phylloxera, a vine-killing root louse, prompted many wineries to plant resistant new rootstock, which allowed winemakers to produce grapes with massive amounts of sugar. Wines with high alcohol, huge fruit, and lots of oak became the norm. Bottle prices rose and the cult wine—Harlan, Screaming Eagle—was born.