Issue link: http://winesandvines.uberflip.com/i/528936
30 WINES&VINES July 2015 GROUNDED GRAPEGROWING populated and dusty. Instead, there are well-planted, lush and attractive suburbs and freeways, golf courses and irrigated turf cov- ering many square miles. Agriculture is also extraordi- nary in this mostly irrigated state. California produces more than half of the nation's fruits, nuts and vegetables, with nearly 25% com- ing from eight counties in the Central Valley. The combination of a great climate, fertile soils, capital for investment, infrastruc- ture and skilled, knowledgeable, hard-working men and women have made this abundant food supply possible. Add to that the attention paid to careful pest management and safe food handling, and there are few other food supplies on the planet that are as depend- ably affordable, healthy and nutritious. While people may question the large amounts of water used by agriculture, it is important to remember that this was a well-supported governmental policy to create adequate water supplies so that agriculture could thrive in our state. Practical solutions Obviously water conservation will play an im- portant role in efforts to improve recharging groundwater levels. Vineyards already are managed frugally with water, since they don't require much irrigation compared to many other crops (almonds, alfalfa, rice, etc.) Most irrigated vineyards are fitted with drip systems that are highly uniform and efficient at deliver- ing water accurately to the vines. Many grow- ers are already practicing regulated deficit irrigation, which uses water strategically in limited amounts to produce high-quality fruit without causing excessive vegetative growth. Future vineyards will most likely use rootstocks capable of absorbing water from lower in the soil profile as a water stress-avoidance strategy. New technologies that can provide data in real time by wireless means (such as surface renewal and soil moisture sensors) will become more com- mon to assist irrigation scheduling as water becomes more scarce or pumping is more regulated. As California's traditional irri- gation source paradigm of snow/ reservoir/groundwater is chang- ing, new ways of thinking about water will have to occur. Recy- cling and repurposing water is one of the obvious ways of in- creasing water supplies. Tertiary treated wastewater can be used directly for irrigation or to re- charge groundwater. Research has shown that winery wastewa- ter can be reused multiple times with the proper cleaning agents and wastewater treat- ment processes. Creating new water sources will be more difficult. Building large new reservoirs is ex- pensive, environmentally challenging and not likely to happen. Already, many vineyards im- pound water by diverting it during high-surface water flows into their own small reservoirs. These could be expanded in places like the North Coast and Foothill regions, where rain- fall is still somewhat dependable and plentiful. It will require running through a gauntlet of regulations and environmental reviews. Barley and mustard didn't grow between these vine rows due to drought. NAPA VALLEY GRAPEGROWERS SUPPORT RESEARCH & WINE INDUSTRY NEEDS THROUGH THE A M E R I C A N V I N E YA R D FO U N D AT I O N P.O. Box 5779, Napa, CA, 94581 • T: (707) 252-6911 Visit our Web site at www.avf.org for information on funding and current research projects T E C H NO L O GY TO I M P R OV E I R R I G AT I O N E F F I C I E NC Y Dr. Andrew McElrone's research defines improvements in the Surface Renewal technique to more clearly evaluate the relationship between real vineyard evapotranspiration and traditional water status indicators such as midday leaf water potential. This valuable information will assist in the development of more efficient vine irrigation strategies and potentially reduce labor costs. For more information visit AVF.org or contact Dr. McElrone at ajmcelrone@ucdavis.edu. For a wealth of useful viticulture and enology research and information, visit AVF.org, ngr.ucdavis.edu, asev.org, iv.ucdavis.edu or ngwi.org Finding Solutions Through Research