Issue link: http://winesandvines.uberflip.com/i/789891
32 WINES&VINES March 2017 T he Lodi wine community has de- voted significant attention and en- ergy to implementing sustainable winegrowing practices since the early 1990s. The focus has been on all aspects of vineyard manage- ment, from soil quality, nutrient and irrigation management to canopy management, energy efficiency, social equity and pesticide risk. A great deal of effort has gone into measur- ing the level of implementation of specific prac- tices, particularly through the Lodi Winegrower's Workbook self-assessment program and the Lodi Rules for Sustainable Winegrowing certification program. However, much less has been done to measure the outcomes of implementing sustain- able farming practices, mainly because it is dif- ficult and expensive to carry out such measurements. The California Department of Pesticide Regulation (DPR) publishes annual reports (Pesticide Use Reporting, or PUR) that provide a unique opportunity to review the ap- plication of pesticides to Lodi vineyards. Since 1989, California growers have had to report the use of pesticides each month to their County Agriculture Commissioner's Office. For each application, they are required to report the pesticide used, how much was applied, the date it was applied and the crop to which it was ap- plied. DPR summarizes this information in an annual report that is available online. I decided to take advantage of this great resource and analyzed the trends in application of several groups of high-risk pesticides to find out if their use has changed in the Lodi region. The results were so dramatic I wanted to report them here be- cause I think it is a great compliment to all the hard work L o d i w i n e g r a p e growers have done to reduce pesticide risk in their vineyards. Pesticides, whether organically approved or conventional, are used to kill pests be- cause they are toxic to them in some way. Some of the newer pesticides stimulate the plant to produce chemicals that are deleteri- ous to pests. Because of these properties, they all have side effects on non-target or- ganisms and the environment. Adverse effects of pesticides are measured using two basic descriptors: hazard and risk. Hazard directly measures the toxicity of a pesticide on lab animals, usually mice. Pesti- cide risk, in contrast, is based on the toxicity of a pesticide as well as the probability of exposure to non-target organisms. Risk is a significant measure because a pesticide can be relatively toxic, but if used in a way that results in little or no exposure to non-target organisms or non-target sites, it is considered a low-risk pesticide. I prefer to focus on pesticide risk rather than hazard when discussing adverse effects, be- cause risk takes into account all the ways grow- ers apply pesticides to reduce the likelihood of exposure to non-target organisms and sites. In other words, it deals in real-world pesticide applications. Fortunately, most of the pesticides used in wine grape vineyards are not only low risk but also low hazard. This is particularly true for pesticides recently approved for use in wine grape vineyards. The California DPR has defined several groups of pesticides it considers high risk in order to help growers identify which ones to use less. Three of these groups contain pesti- cides that are used in vineyards. One group consists of pesticides that are on the Proposition 65 list of chemicals that research has shown to cause cancer in lab animals exposed to a high dose over time. These include Diuron, Manco- zeb, Surflan and Omite. Another group contains herbicides that have the potential to leach through soil and contaminate groundwater, particularly in soils with a high sand content. These include Diruon, Solicam and Simazine. A third group is comprised of pesticides re- search has indicated may act as reproductive toxins in humans exposed to high levels. These include Agrimec, Rally and Omite. I used data from the Pesticide Use Reports available online to analyze trends in these three groups of pesticides in Lodi vineyards. The Lodi Winegrape Commission boundaries are California Crush District 11, which strad- dles both San Joaquin and Sacramento coun- ties. Therefore, I summarized the PUR data from both counties. Pesticide use data is reported in pounds of pesticide active ingredient applied per year to wine grape vineyards. An active ingredient is Vineyard View n CLIFF OHMART Lodi Growers Reduce Pesticide Risk 140,000 120,000 100,000 80,000 60,000 40,000 20,000 0 POUNDS OF PROP. 65 ACTIVE INGREDIENTS APPLIED PER YEAR 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 Data for Sacramento County and San Joaquin County vineyards, according to Pesticide Use Reporting from the California Department of Pesticide Regulation. Pounds of Active Ingredient Year