Innovations in the Vineyard
A postwar spirit of experimentation and innovation infused and shaped the development of the California wine industry. Instead of returning to pre-Prohibition methods and varieties, grape growers and winemakers turned to science to find out what grapes to grow and where to plant them. The University of California at Davis was at the forefront of this new viticulture and enological research.
Scientists undertook climate studies to determine the best places to grow different types of grapes, and developed optimal designs for new vineyards, including spacing of plants and trellising systems. Other studies determined best vineyard practices, including crop irrigation, canopy management, fertilization, and pest control, and developed disease-resistant rootstock. Davis scientists urged the new winemakers to plant French varietals such as Cabernet Sauvignon, Merlot, Pinot Noir, and Chardonnay.
Before there can be any wine, there must be suitable grapes. Before there can be suitable grapes, there must be a climate they will find congenial. California illustrates these statements.
—Maynard A. Amerine
In the 1940s, University of California scientists Maynard Amerine and A. J. Winkler studied the wine-producing regions of California. They recorded the “degree days,” the number of degrees above 50°F per day between April 1 and October 31, the growing season for most grapes. This research established the effects of climate and grape variety on the quality of wine and became the basis for recommending specific grape varieties for each region.
This advice was put into practice in the 1960s, when new investments enabled growers to replant. The methodology was adapted by growers in other parts of the country and around the world.
Harold P. Olmo developed disease-resistant rootstock and established the California vine-certification program for supplying strong, disease-free plants to the state’s growers. Olmo researched the genetic type (clone) of Chardonnay grown in California, which had low yield and little flavor. His work led to better plant clones that vastly improved the quality of California Chardonnay. By the end of the 1900s, Chardonnay was the most widely planted white-wine grape in the state.
Mechanizing the harvest
As the wine industry expanded in the 1960s, so did the need for labor to harvest the grapes. The need was great in the large vineyards of the Central Valley, which has always produced the majority of the grapes used to make California wine. While the government-sponsored Bracero Program supplied labor in the form of Mexican guest workers until 1964, growers were already looking for ways to mechanize the harvest.
The impact of harvesting machines on labor was significant; by the 1970s, most of the Central Valley vineyards were machine-harvested. California’s smaller estate wineries never adopted mechanical harvesters, but continued to hire crews to hand-harvest grapes.
At the time I put my vineyard in  the University at Davis was encouraging the ranchers to put in the better varieties like Chardonnay and White Riesling and Cabernet and Pinot Noir . . . I didn’t know anything about viticulture and enology. . . . All I did was to do what the experts were telling me to do and it worked out very well.
Nathan Fay was among the grape growers who heeded the advice of Davis scientists on the best varieties for California’s climate regions. He bought a ranch in the Napa Valley in 1953 and in 1961 he planted the first Cabernet Sauvignon vines in what became the Stags Leap District of the valley. At the time there were only 800 acres of Cabernet in the entire country and Fay’s seventy acres represented a major increase in U.S. production of the classic French varietal. Since Fay’s first planting, Cabernet Sauvignon has become the premier red varietal in the various appellations in the Napa Valley, including Stags Leap and Oakville.
I tasted that wine and it began . . .
In 1969, winemaker Warren Winiarski asked grape rancher Nathan Fay for advice on irrigation machinery. During that discussion, Fay poured a glass of his homemade Cabernet, and Winiarski was hooked. Learning that the thirty-five acres of land next to Fay’s ranch were for sale, he bought them to grow his own Cabernet. He replanted that land, naming it SLV for Stag’s Leap Vineyard.