Viticulture and Enology Extension News Washington State University SPRING 2014 CONTENTS NOTE FROM THE EDITOR Spring is finally here! Irrigation is set for full allotment this summer, buds are swelling, vines are bleeding, and the inevitable vineyard-tripping-due-to-badger-holes has com- VITICULTURE menced. It is good to shake off that winter dormancy. Quarantines ........................ Page 2 This issue of VEEN is an eclectic mix of rules and research, theory and practice. Washing- ton’s grape quarantines are explained, and a highlight of how the Clean Plant Center - Fruit-Zone Leaf Removal ...... Page 3 Northwest is keeping our Foundation Grapes clean is presented. Canopy management and mite resistance management research by two recent graduates are discussed, as 2013 Weather Review .......... Page 6 well as ground-breaking information on how “native” yeasts can be put to good use in the vineyard. Weather from 2013 is explained, and questions on irrigating different Indigenous Yeasts ............ Page 7 soils are answered. We also have part one of a two-part series on fruit and wine acidity. Mites ............................. Page 8 Click print, or download to your smart device and begin reading---just watch out for Virus Detection ............... Page 9 those badger holes! Irrigation Mgmt .............. Page 11 Michelle Moyer Viticulture Extension Specialist WSU-IAREC ENOLOGY High pH / High TA ............... Page 12 OTHER NEWS FIND US ON THE WEB: Extension Publications ..... Page 14 www.wine.wsu.edu/research-extension Calendar of Events ........... Page 14 Information when you need it. That is the power of the internet! Visit the WSU Viticulture and Enology Research and Extension website for valuable information regarding research programs at WSU, timely news releases on topics that are important to your business, as well as information regarding upcoming workshops EDITOR and meetings. Michelle M. Moyer, PhD It is also a valuable site for downloading our most recent Extension publications, in addition to archived articles and newsletters you can print on demand. Find quick WSU Extension programs and em- links to AgWeatherNet, the Viticulture and Enology Degree and Certificate programs, ployment are available to all without as well as to other Viticulture and Enology related resources. discrimination. Evidence of noncompli- Find us on Facebook ance may be reported through your local WSU Extension office. Go to: www.facebook.com/WSU.Vit.Enol.Ext and “Like” the page! 1 Understanding WA Grapevine Quarantines By Michelle Moyer, WSU-IAREC Washington has several unique factors that truly make it the perfect climate Quarantine Information for wine. Low rainfall east of the Cascades allows growers to control Information on plant quarantines can be found at the Washington State De- water; variable growing season lengths partment of Agriculture’s website : and heat accumulation across the state allow for the production of nearly every http://agr.wa.gov/PlantsInsects/PlantQuarantines/PlantQuarantines.aspx kind of variety and wine style. One of the biggest advantages to commercial grape production in Washington, these quarantines is simple: don’t bring a Washington-recognized certification however, is the relatively low disease in infested or diseased plant material program. The “certified” stamp and pest pressure. from out of the state/country. indicates that the original source plant material came from a grape Foundation Lack of established phylloxera Specifically, Washington has twoProgram (has been “cleaned up” of populations allows Washington quarantines in place for grapes. The potential diseases) and was propagated producers to grow Vitis vinifera on its first quarantine (WAC-16-481) is and grown at a certified nursery that own roots; a substantial advantage in directed at reducing the introduction met strict standards in routine testing regions where cold damage is a threat. of insect pests, specifically phylloxera of the plant material and vineyard The lack of native grape species reduces (Daktulosphaira vitifoliae) and vine maintenance to maintain the disease- the likelihood of field-infection of the mealybug (Planococcus ficus). The free status of the plant materials. Crown Gall bacterium (Agrobacterium second quarantine (WAC-16-483) is Washington currently only recognizes vitis). The warm, dry growing season directed at reducing the introduction certification programs from California, conditions in eastern Washington of three different virus diseases: Oregon, Canada, and of course, itself. make it the envy of other regions; Fanleaf, Leafroll, and Corky Bark. Interestingly, the nursery certification these conditions allow for substantially These quarantines require grapevine program in Washington tests for and reduced spray programs for powdery materials from outside of the state to excludes the viruses that cause Stem mildew and Botrytis bunch rot. Due show proof that they are free of these Pitting and Red Blotch diseases; the to these reduced pesticide inputs, pests and diseases before being allowed California certification program does Washington producers are able to into the state. This proof is typically a not. What this means is that certified sustain high populations of beneficial “phytosanitary certificate” issued by plant material from California that meet insects, which keep pest insects (mites, the state of origin’s plant regulatory Washington quarantine regulations, leafhoppers) at manageable levels. agency. may harbor these viruses since they are not specified in the Washington The best defense, however, in Under the insect quarantine, both quarantines. Washington’s pest and disease vineyard equipment and grapevine management routine is the relative materials are regulated. Equipment All out-of-state materials are subject to isolation of the state due to the originating from out of the state both quarantines. It is the purchaser’s bordering mountain ranges and ocean, must be thoroughly cleaned of soil responsibility to make sure all proper and lack of exposure to, and build up and debris before entering the state. notifications are made to the WSDA. of, other diseases due to the relatively Plant materials, however, must either: Most reputable, certified nurseries will young age of the industry. These (1) Be grown in an area that is free either do this documentation for you, factors have protected Washington of phylloxera and vine mealybug; (2) or help you with the process. This producers from a range of pests and Be grown in sterile media and pass a translates to: the only way to legally diseases that threaten the grape visual inspection that they are free of bring in grape material from outside industries around the world. The big the quarantine pests (if the shipment of Washington is if it is “certified” from question is, with the world becoming is small, <500 cuttings, the visual California, Oregon or Canada, and it an increasingly smaller place, how can inspection is the only requirement comes with a phytosanitary certificate Washington keep this “isolation” while needed), if they are from an area that showing it is pest free. expanding the industry? The answer: is not free of the quarantined pests; plant quarantines. or (3) Be subjected to one of two Think “clean” plants. Never plant different treatments that reduce or material from out of state, unless it In order to protect its large agricultural eliminate the quarantine pests. The was certified; it’s the law. Those vine industry, Washington has very strict different treatments that are approved cuttings collected while on a recent out- laws on what kinds of plant materials are: Dormant hot water treatment of of-state trip? They are illegal to bring can come into the state. These laws are cuttings or methyl bromide fumigation in, plant, or distribute in Washington. designed to prevent the introduction of dormant cuttings. Knowledge and experience from other of unwanted pests and diseases that regions can help continue to propel the could result in collapse of any one of Under the virus quarantine, the only Washington grape and wine industries our major crop systems. From a grape legal way grape materials can enter the forward, but not all legacies are worth standpoint, the general idea behind state is if they are “certified” through sharing. 2 Early Fruit-Zone Leaf Removal in Washington By Brittany Komm, Graduate Student, and Michelle Moyer, WSU-IAREC Early fruit-zone leaf removal (FZLR), the the canopy. The same ex- act of removing all or varying degrees perimental design was car- of all, the leaves within the fruiting zone ried out in 2012 and 2013; in winegrape canopies, has gained re- that is, the vines received search interest in recent years. Studies the same leaf removal done around the globe have focused treatments in both years. on how the timing and severity of FZLR impact vine growth and development, Impacts of FZLR on Vine and fruit quality. Many of these stud- Development and Yield. In ies have demonstrated that early FZLR 2013, total leaf area (TLA) can reduce fruit set, which is beneficial that was removed during in some situations where yields need to each FZLR treatment was be controlled but laws prohibit vine- evaluated. In Riesling, pre- yard activities. bloom, bloom and 4 weeks post-bloom FZLR resulted Figure 1- Water-sensitive cards post-chemical application Eastern WA’s unique climate offers in 60%, 50% and 22% during bloom in Riesling.’Cards were placed directly in the growers opportunities to optimize TLA removed, respectively. fruit-zone. At the time of assessment, only the pre-bloom and bloom treatments had undergone fruit-zone leaf re- both horticulture and pathology goals In Sauvignon blanc, pre- moval. Average coverage for both cultivars are indicated in in vineyard management. Can early bloom, bloom and 4 weeks the image. Photo by Brittany Komm. FZLR be implemented as a part of these post-bloom FZLR resulted goals in our climate? This question has in 53%, 35% and 18% TLA Clusters per shoot, was influenced by been investigated over two growing removed, respectively. early FZLR. Pre-bloom and bloom FZLR seasons (2012 and 2013) in commer- resulted in significantly more clusters cial blocks of V.