Fruit Quality
Erratic weather like deluge rain, longer falls, and patches of drought disrupt vinifera’s adaptation to long-sustained winters. Jason Londo (Cornell AgriTech) is working to identify the right grape for the right climate.
Ecosystem Science combines biology, chemistry, and physics to model and predict responses like wine grape yield forecasting, water management, and disease vector mapping. Joshua Fisher from Chapman University explains how high-resolution data from space helps farmers plan for climate change.
High temperatures and extreme weather events can have numerous impacts on wine grapes and ultimately wine quality. Dr. Andreea Botezatu at Texas A&M University is experimenting with verjus aka "green wine" to balance acidity and pH.
Sunburn with the associated severe water stress have resulted in significant yield loss and poor berry quality at harvest. Berry sugar, organic acids, anthocyanins, and phenolics all can be impacted by extreme daily temperature.
Sunlight into Wine sets out the principles of canopy management to improve winegrape yield and quality. It brings together for the first time the findings of viticultural research and advances in commercial grapegrowing practice over the last decade or so.
Amid extreme weather events, many grape growers ask themselves what they can do to adapt their vineyard for climate change. Chris Chen, Integrated Vineyard Systems Advisor in Sonoma, Mendocino, and Lake Counties at the University of California Cooperative Extension is exploring solutions to this question.
The study of whole vine physiology does not isolate one variable in grape growing. It looks at many factors at once including data collection in the plant, in the environment and the in fruit. In her research, Patty Skinkis, Viticulture Extension Specialist and Professor in the Horticulture Department at Oregon State University helps growers improve their farming practices by evaluating the plant growth stage, shoot growth, pruning weights, yield, cluster weight, berry size, and fruit chemistry.
As a vineyard advisor across the United States, Fritz Westover, Viticulturist at Westover Vineyard Advising and host of the Virtual Viticulture Academy, has the opportunity to see a lot of different vineyards, varieties, diseases and climates. Fritz discusses a variety of practices that impact the long-term sustainability of a vineyard including leaching salts, why irrigation systems are important in wet climates, and the number one way to manage disease.
Grape growing regions are facing constant warming of the growing season temperature as well as limitations on ground water pumping used for irrigating to overcome water deficits. Trellis systems are utilized to optimize grapevine production, physiology, and berry chemistry. This study aimed to compare 6 trellis systems with 3 levels of applied water amounts based on different replacements of crop evapotranspiration in two consecutive seasons.
Arbuscular Mycorrhizal Fungi, known as AMF, has an interesting an important relationship with plants, grapevines included. AMF helps vines take up mineral nutrients, creates a layer of protection from pathogens by occupying plant cells, and seems to improve soil structure and water movement. In turn, grapevines supply carbohydrates to the fungus. Scientists believe the pant calculates the value of giving carbon in exchange for nutrients provided by the AMF.
As researchers were creating a training procedure to identify smoke-tainted wines, they made a breakthrough discovery that links a class of sulfur-containing compounds called thiophenols to the undesirable ashy flavors found in impacted grapes. Elizabeth Tomasino, Associate Professor, Department of Food Science and Technology at Oregon State University shares what this breaking news means for the future of smoke-tainted wines.
Worried about smoke taint? Anita Oberholster, Professor Cooperative Extension Enology in the Department of Viticulture and Enology at the University of California, Davis talk about varieties that can mask smoke flavors, how our senses detect ashy flavors, barrier spray research and gives her number one tip for growers.
There are three levels of cold hardiness in grapes and understanding these can help growers select and manage the best varieties for their region. Imed Dami, Professor of Viticulture in the Department of Horticulture and Crop Science at The Ohio State University, explains cold tolerance and new information about the role of abscisic acid in ripening.
What, bury charcoal in the vineyard? Biochar is a specialized form of charcoal made from waste woody biomass at high temperature in the absence of oxygen. Doug Beck, Science Officer at Monterey Pacific in Monterey California, shares how biochar and compost amendments improve nutrient efficiency, improve water holding capacity, and positively impact yields.
Once a vineyard manger has found disease there is often not much to be done, they are merely mitigating loss. The Lab at Cornell has launched several projects utilizing imaging spectroscopy (also known as hyperspectral imaging) deployed at all scales, from autonomous rovers to spacecraft with the goal to detect disease earlier when management is going to be both minimal and successful.
Second generation owner of the Original Wine of the Month Club and host of the podcast Wine Talks, Paul K. knows you need to taste a wine to know if it is good. Decades in the industry have taught Paul that a sustainable business means being able to go to market through different routes so consumers can buy at varying price points. Paul reflects on shipping challenges from reporting to taxes; misconceptions about the quality of wine coming from the bulk market; and the slow road to pivot from on premise sales to online post COVID.
The Spotted Lanternfly (SLF) is the newest agricultural invasive species in the United States. Originally from Asia, this insect feeds on plant sap from a broad range of hosts. Dr. Heather Leach, Extension Associate at the Department of Entomology at Penn State University is focused on researching this insect and educating the public on how to manage the pest. Although it appears that SLF has been in the United States for some years, growers are now seeing adverse effects and report extreme vine decline and death.
Leading expert Dr. Andrew Landers of Cornell University discusses his more than thirty years of research and development on pesticide sprayer technology to reduce pesticide use through accurate, efficient delivery of the product to the plant.
A recent study examined the potential of hemp terpene drift from hemp crops planted in close proximity to vineyards in Sonoma County, California. George Sellu, Program Coordinator and Instructor in the Agribusiness department at Santa Rosa Junior College explains the nuances of hemp production from how volatile aroma profiles vary by variety, the lack of studies to show volatiles impact grapes, wind influence on volatile organic compound movement, and smoke taint.
Bruce Reisch, Professor of Grapevine Breeding and Genetics at Cornell University, specialized in the development of new wine and table grape varieties, as well as new grape breeding techniques. Of the more than 60 grape species available, most of the grapes we are familiar with come from European vitis vinifera. Unfortunately, this species offers little disease resistance, but other species have better sources.
Sustainability and certification are viewed as a “quality enhancement”. In the currently overly supplied market, sustainability is an advantage. A premium can be getting $200 to $300 more per ton of grapes in a good market or it can mean selling grapes when no one else can in a weak market. Gregg Hibbits, General Manager at Mesa Vineyard Management explains how their dedication to sustainability for over 30 years has drawn like-minded customers to their organization.
Wayne Wilcox, Professor Emeritus of Plant Pathology and Plant-Microbe Biology at Cornell University, spent his career on the applied biology and integrated management of grapevine fungal diseases. His applied research sought to discover what makes a “disease tick” and use that knowledge to learn how to better target the disease.
One decade ago, amidst a limited labor supply and growing New Zealand wine industry, Klima co-founders Marcus Wichkam and Nigel George set out to solve their own labor issues with mechanization. By developing a highly efficient vineyard pruning system they have removed the physically demanding portion of the job opening the opportunity to employ fewer, more highly skilled tradesworkers to perform cane selection.
California has seen another challenging and sometimes devastating year of fires. Smoke from these events can cause unwanted flavors in wine. Eric Herve of ETS Laboratories and Matt Brain of Chamisal Vineyards, discuss how winemakers can screen grapes for the risk of smoke impact and work to mitigate its effects.
Gerhard (Gerry) Pietersen is a plant virologist with an interest in solving problems in South African agriculture related to plant viruses. In this interview Gerry discusses the severe plant health and economic impacts seen in South Africa from Grapevine leafroll disease, the importance of regional buy in to establish a control program including a very successful collaboration of 50 adjoining farms in New Zealand, and new techniques to detect the virus including loop-mediated isothermal amplification (LAMP) and grafting sensitive red cultivars on white cultivars to use the shoot as an indicator.
Dr. Michelle Moyer of Washington State discusses recent research on integrated pest management for grapevine powdery mildew, how short term weather patterns impacts farming decisions, why clean plants may have made red blotch virus more detectable, controlling wine quality with water stress and “Farming by Excel” – how fewer people working in the field has increased growers reliance on data and technology.
Gregory V. Jones, Director of the Evenstad Center for Wine Education, at Linfield College in Oregon discusses climate structure and suitability for viticulture, how climate variability and change influence grapevine growth, wine production and quality, why we plant only a few hundred of the of the more than 24,000 varieties, how warm climate winegrowing regions have hedged against climate risk by growing multiple varieties, factors beyond fossil fuels that affect climate change, and our biggest challenges ahead.
Dan Rodrigues, Owner of VinaQuest, talks about how the loss of materials impacts farming; disease management for mildew, sour rot, and weeds; the effects of a wet winter; and what trends he sees for the future.
Audra Cooper, Broker/Partner at Turrentine Brokerage talks about what wine and grape brokering is, the factors that affect grape pricing, the 2018 grape market, how sustainable certification can help set grapes apart in a crowded market, and the quality of the 2019 crop.
Heat waves with extreme daily temperatures are becoming more and more common in the San Joaquin Valley. Sunburn with the associated severe water stress have resulted in significant yield loss and poor berry quality at harvest...
Dr. Stephanie Bolton, Sustainable Winegrowing Director, Lodi Winegrape Commission, talks about sustainable farming in the Lodi winegrowing region.
Jeff Newton President & CEO, Costal Vineyard Care Associates discusses his career and the history and future of the Santa Ynez American Viticultural Area.
Fritz Westover, viticulturist with Westover Vineyard Advising and Virtual Viticulture Academy describes growing conditions and challenges in multiple states in the Southeastern United States.
Results from four harvest-years showed a higher productivity, up to 66% with no significant differenceswere observed in grape quality parameters. The observed increase in productivity was inversely correlated with rainfall in the vegetative period. These findings support the feasibility of a biochar-based strategy as an effective adaptation measure to reduce the impact of water stress periods with no negative effects on grape quality.
Mark Greenspan, Ph.D., President and Viticulturist, Advanced Viticulture, Inc. shares his insights on irrigation scheduling, technology in the vineyard, and more.
Diurnal changes in berry size pre- and post-veraison.
A study of how water flows into to and out of grape berries pre- and post-veraison.
Sometimes a series of short irrigations are better than one long irrigation.
Mark Chien shares highlights from his career helping grapegrowers in some of the most difficult growing regions in the world. From his years as a vineyard manager to Penn State viticulture extension agent, and now Program Coordinator for the Oregon Wine Research Institute.
Kris Beal, M.S., Executive Director of Vineyard Team, recounts some of the history of the organization, it’s current activities and what the future holds in store.
Dr. Kari Arnold talks about Grapevine Leaf Roll-associated Virus 3, its vector the vine mealybug, and how growers can manage the spread of viruses both within and between vineyards.
Dr. Kari Arnold talks about Grapevine Leaf Roll-associated Virus 3, its vector the vine mealybug, and how growers can manage the spread of viruses both within and between vineyards.
Dr. Michael McCarthy, Principal Scientist-Viticulture, South Australia Research and Development Institute, PIRSA, describes viticultural research in Australia.
Vineyard Team Technical Program Manager Dr. Craig Macmillan discusses the theory and assumptions behind crop estimation.
Recommendations for control of stinkwort.
Description of the weed stinkwort (Dittrichia graveolens), its rapid spread through California, and its life cycle.
Two articles on the spread, biology, and control of stinkwort (Dittrichia graveolens).
Ashley Poupart explores why sustain practices are important to the wine and winegrape industries followed by an overview and comparison of the major sustainability certifications available to vineyards.
Bart Haycraft, Vineyard Manager for Jackson Family Wines Los Alamos, walks through all of the vineyard operations he has mechanized on his ranches including weed control, canopy management and efficient harvesting. Q&A for this session is found here: https://youtu.be/nC1gSjtU1QM
Dr. Kaan Kurtural, Assistant Cooperative Extension Specialist with UC Cooperative Extension describes the benefits of mechanizing viticultural operations. Q&A for this session is here: https://youtu.be/JUF1FaEUudE
Bart Haycraft, Vineyard Manager for Jackson Family Wines Los Alamos, answers questions about the vineyard operations he has mechanized on his ranches including weed control, canopy management and efficient harvesting. The full session is found here: https://youtu.be/ItFu_50H0og
Dr. Kaan Kurtural, Assistant Cooperative Extension Specialist with UC Cooperative Extension answers questions about the benefits of mechanizing viticultural operations. The main talk is found here: https://youtu.be/V6gQ-KJ_XFM
Check out some favorite episodes Here are ten episodes of the Sustainable Winegrowing podcast you don’t want to miss.
Jackie Dresser, Viticulture Extension Support Specialist at the Lake Erie Regional Grape Program talks about her work on improving the accuracy of vineyard yield estimates.
Jackie Dresser, Viticulture Extension Support Specialist at the Lake Erie Regional Grape Program talks about her work on improving the accuracy of vineyard yield estimates.
Multiple crop estimation methods are described including the use of Growing Degree Days to predict final yield.
Capturing images of grapes under bright light at night is used to estimate final vineyard yield.
A vision system mounted on a vehicle automatically and accurately estimates final vineyard yield.
An automated system was used during three growing seasons to monitor the change in tension in the load-bearing wire of a trellis to estimate yield in vineyards.
A survey of automated image processing methods for estimating final vineyard yield from images.
Improving Yield Estimates: You can improve the accuracy of your estimates when you think about the assumptions behind how and how much to sample. Slides from Dr. Craig Macmillan's talk at the Crop Estimation Tailgate-3/15/18
A brief summary of the key points made by Dr. Tim Miles during his talk at the February 23, 2018 Fungicide Resistance Tailgate.
Peter Work - Owner, Winemaker, and Vineyard Manager of Ampelos Cellars - recounts how becoming a certified organic vineyard led to becoming Demeter® biodynamic certified and eventually Sip Certified®.
Reflections, insights, and advice on the 2017 powdery mildew season by Dr. Walt Mahaffee, Research Plant Pathologist, USDA-ARS Horticulture Crops Research Unit . Topics include timing, coverage, vine microclimate, canopy management and more.
These excerpts from the 2017 edition of this UCIPM text describe and explain fungicide resistance and include tables listing fungicides registered for grapes with their known efficacy against various diseases and their resistance risk as of 2017.
This article from WSU Extension provides an overview of yield estimation methods meant to improve the accuracy of your crop estimates.
How to Collect and Use Pruning Weights
A field study was conducted in north-central San Joaquin Valley of California to deduce the interactive effects of irrigation and mechanical canopy management on the phenolic composition of grape and wine, and volatile compounds of the wines produced from Syrah.
Chandra Krintz, Ph.D., Professor of Computer Science, University of California Santa Barbara explains how scientists and engineers are working on a computer system that will help farmers make better decisions using data analytics.
The develop of fungal diseases on grapes is a progression from powdery mildew in the spring to Botrytis in the late summer.
Justine Vanden Heuvel explains how computer algorithms can tell growers where to sample in the vineyard by analyzing digital images saving time and money.
The research of Megan Hall and others has advanced our knowledge of the etiology, epidemiology, and management of sour rot from what we knew four years ago. Her research sheds light on the role of fruit flies in this disease complex.
The crop looks good and canopy growth is strong.
What is smoke taint, when is the window of susceptibility, and is there anything you can do?
Sustainability rests on the principle that we must meet the needs of the present without compromising the ability of future generations to meet their own needs.
Doug Beck, Science Advisor for Monterey Pacific Inc., talks about the different types of technology used in the vineyard.
A grower panel discussion on preventative and management practices for grapevine trunk diseases and Red Blotch Virus management.
Smoke taint is one or more off-aromas or flavors in wine or juice that are the result of the grapes being exposed to smoke.