Category: Archived Articles

By: Judit Monis, Ph.D. – Vineyard and Plant Health Consultant

Grapevine trunk diseases occur worldwide and are caused by bacterial, fungal pathogens, or a combination of both. Important trunk disease fungal pathogens are airborne and not only affect grapevines.  Many, also cause disease in landscape and fruit trees and can be found colonizing the orchard or vineyard soil.   Grapevine stock can be infected with important pathogens which makes it important to screen nursery material for their presence prior to planting.

  In a recent article, I covered the bacterial trunk disease caused by Agrobacterium vitis.  This article will focus on grapevine trunk diseases caused fungal pathogens.  As with viruses and bacteria, fungal pathogens can be found in mixed infections exacerbating the problem in a vineyard.

Petri Disease, Young Vine Decline, Esca:  The disease in young vines, known as young vine decline, is caused by Cadophora, Phaeoacremonium, and Phaeomoniella species.  In older vines, the same fungal pathogens are associated with Esca disease.  The disease is chronic when vines express a gradual decline of symptoms over time, or acute when the vines decline and die within a few days.  These acute symptoms are known as the apoplectic stage of the disease. It is not uncommon during the apoplectic stage of the disease to see dead vines carrying mummified grape bunches.

Canker Diseases:  Various pathogens can cause canker symptoms, large discolored areas in trunk and canes (Photo #1), in the vineyard. Bot-canker or dead arm disease is caused by different species in the Botryosphaeriaceae family.   The most severe Bot-canker species is Lasidiplodia theobromae, while weaker symptoms are caused by Diplodia species.   Eutypa dieback is caused by different species in the Diatrypaceae family.  The best characterized and known species is Eutypa lata, but species of Criptovalsa, Diatrypella, and Eutypella can also cause canker disease in grapevines.  In my lab we characterized Seimatosporium species as a fungal pathogen that causes decline and cankers in grapevines, but within the same fungal group others have reported Pestalotoipsis and Truncatella to cause disease in grapevines.  Another canker pathogen includes Diaporthe (also known as Phomopsis).  The canker symptoms observed in the sections of affected cordons or trunks in grapevines may appear to be similar but caused by unrelated fungal species, however, the life cycles and mode of infection may be different.

Black Foot Disease:  Species of Campylocarpon, Cylindrocladiella, Dactylonectria, and Ilyonectria (previously known as Cylindrocarpon spp.) are the causal agents of this complex disease.   These fungi are soil-born and most active on compact soils with poor drainage.  Symptoms above ground can be indistinguishable from young vine/ Esca disease described above.  Additionally, the decline symptoms can be confused with Pierce’s disease, caused by Xylella fastidiosa, a bacterial pathogen.

Sudden Vine Collapse Syndrome (previously known as Grapevine Mystery Disease):  Some years ago, Lodi growers in California reported a syndrome in which their vines collapse and die within a short period of time.  In 2011, while working at STA, we tested vines with similar symptoms, not just from Lodi, but from California’s Central Valley, and Central Coast vineyards (see photo #2).  We detected a combination of fungal pathogens (not always the same usual suspects) and viruses, namely Grapevine leafroll associated -3 (GLRaV-3) and Grapevine virus A and F (Vitiviruses). 

  Researchers at the University of California at Davis with fungal expertise (Dr. Akif Eskalen) and viral expertise (Dr. Maher Al Rwahnih) have continued to work on vines expressing the sudden vine collapse syndrome.  Samples from symptomatic vines were subjected to high throughput sequencing to look for viruses in Al Rwahnih’s laboratory.  Concurrently, fungal culture work was performed in the Eskalen laboratory.  Interestingly, the results were similar to those found in my laboratory: various fungal pathogens (not consistent in every sample), GLRaV-3, and Vitiviruses were detected in the collapsed vines. This year, these researchers concluded (Eskalen’s presentation at the 12th International Workshop on Grapevine Trunk Diseases) that the syndrome is not caused by one single organism but a combination of viral and fungal pathogens.

Other diseases:  Species of Armillaria mellea (Oak root fungus), Phytophthora, and Verticillium are soil-born fungal species capable of causing decline and rots in the vineyard.  Just as described above for black foot disease, these pathogens strive in compact soils with poor drainage.

Disease Prevention and Management:  The best disease management and control measure recommended is to prevent the introduction of pathogens in the vineyard.  None of the US-certification programs exclude trunk disease pathogens.  Therefore, propagation material is most likely infected with various fungal pathogens. 

  The implementation of appropriate sanitation measures at the nursery is most needed to produce high quality planting grapevine material.  It is known that one infected vine can produce between 100 -200 vines each year, potentially producing a significant number of infected grafted plants.  The use of hot water treatment (HWT) for 30 minutes at 50C (122F) at the nursery has shown a reduction of fungal pathogens in propagated vines.  However, there are mix reports on the effect of the HWT on bud mortality.  Reports in warmer winegrowing regions (e.g., Spain) have shown a lower effect on bud mortality compared to HWT in cool climate regions (e.g., Australia).   Because fungal pathogens cannot be eliminated in the vineyard once introduced, it is important to learn and apply the best management practices available. 

  When planting a new vineyard, it is important to inspect the quality of the planting material (graft union integrity, lack of galling, absence of streaking or pitting).  High quality planting material must be planted in well prepared and drained soil, at the correct season.  The best practices in the vineyard must be applied (i.e., enough water, nutrients, etc.).  Many of the fungal pathogens that cause disease in grapevines are endophytic, meaning that these can live in the vine without causing disease.  However, these same fungi can become pathogenic during stress situations (lack of water, heat wave, etc.).

  It is known that the effect of grapevine fungal pathogens increases as the vineyard ages (the fungal population continues to multiply seasonally).  Therefore, growers must adopt management and control measurements as soon as the vines are planted in order to prevent and minimize the propagation and dispersal of fungal pathogens.

  Management at the vineyard should include expertly trained personnel for pruning activities.  In California where the rainy season coincides with the pruning season it is recommended to prune as late as possible in the spring prior to bud break. Since the vine is active in the spring, the wound healing will occur faster.  Another reason for late pruning is that most fungal trunk disease pathogens release spores during the rainy season.  Therefore, in areas with predominantly winter precipitations, the proportion of spores available to start an infection would have been reduced to a minimum.   If the vineyard is large, the double pruning method is recommended. This consists of the mechanical pre-pruning of vines in the start of dormancy, leaving canes of 1-2 feet long.  In the spring or late winter, the pruning is completed by leaving the desired final number of buds per spur. The freshly produced wounds should be protected using fungicides or a sealant such as VitiSeal.  During pruning it is important to avoid producing large wounds, cutting near the trunk, pruning after long periods of rain, and leaving vine residues in the vineyard floor.

  Economic studies performed by Dr. Kendra Baumgartner and colleagues (USDA in UC Davis, California) has shown that preventative methods (late pruning, double pruning, and pruning wound protectants) are sustainable only if applied before symptoms appear in the vineyard.  Adopting these methods in vines that are 10 years old or older will not recover the cost of investment.

  A more drastic disease management practice includes vine re-training also known as remedial surgery.  The procedure consists of training a new shoot from the base of the trunk to replace the old decayed vine trunk or cordons.  The technique can help gain some years of production but will not cure the vines from the disease as likely the pathogens are systemically established in the vine.  Keep in mind that the pathogenic fungi are systemic in the vine, and as mentioned earlier this method can buy some time before the vine declines and dies.  When replacing vines, the grower must understand that fungal pathogens are able to survive in dead portions of the roots, therefore new vines that are planted (even if free of bacterial or fungal pathogens) can become infected over time if vine roots are not completely removed from the vineyard.

  Other methods that have been reported for the management of fungal diseases include planting mustard (Sinapsis alba) plants as cover crops that act as a biofumigant and biological control agents such as Trichoderma species, and mycorrhizal fungi. This year, at the 12th International Workshop on Grapevine Trunk Diseases, Josep Armengol and collaborators (Universidad Politecnica de Valencia) reported a decrease in spore dispersal in grass and cover crop plots relative to the bare soil plots.

  New and more sensitive pathogen detection methods that apply next generation sequencing (also known as high throughput sequencing) are now available commercially for the detection at the species level of microorganisms in plants and soil.  It is expected that the application of early and efficient diagnoses will help reduce the infection levels of planting material and consequently avoid disease onset in the vineyards.

  Judit Monis, Ph.D. is a California-based plant health consultant, provides specialized services to help growers, vineyard managers, and nursery personnel avoid the propagation and transmission of disease caused by bacteria, fungi, and viruses in their vineyard blocks.   Judit is fluent in Spanish and is available to consult in other important wine grape growing regions of the word.   Please visit juditmonis.com for information or contact juditmonis@yahoo.com to request a consulting session.

By: Becky Garrison

Losses in soil structure, erosion, and overall soil health continue to be a hot topic amongst farmers, including grape growers. A virtual session on soil health was held at the Oregon Wine Symposium in February 2022 and moderated by Patty Skinkis, a viticultural specialist and professor at OSU.

Defining Soil Health

  Dr. Shannon Cappellazzi, the director of research at Grassland Oregon, defined soil health as “the continued capacity of the soil to function as a vital living ecosystem that sustains life.” Soil is needed to move, filter and store the water needed to sustain plants, as well as serve as the medium for nutrients such as dead and decaying animal material, manure and plant matter to get recycled and taken up by plants and other soil biota.

  In addition, soil is the modifier of the atmosphere. According to Cappellazzi, there’s about three times as much carbon in the soil as there is in the atmosphere. “The balance of the amount of carbon that is coming out of the soil on a daily basis naturally as it’s supposed to be, and the amount of carbon that’s going back into the soil is really critical to those atmospheric levels of carbon dioxide.” Also, soil is a habitat for organisms, such as insects and other kinds of arthropods, microorganisms, fungi and a host of other organisms.

Role of Plants in Soil Health

  Cappellazzi observed how there’s a growing realization that biology controls so much of what’s going on underground and about plants’ role in maintaining soil health. First, plants help prevent erosion from the elements by holding the soil in place, regulating temperature and moisture and helping moderate pests and diseases. In particular, the roots create pathways for the water, invertebrates, some mammals and gases to move in and around the soil. Along those lines, when the mycorrhizae fungi grow with plants, they increase the root surface area and create enzymes that break nutrients down, thus enabling the soil to get more nutrients.

  Also, microbes help form the glue that holds the soil together. When sand, silt and clay-sized particles get stuck together in these aggregates, they start to create pore spaces that allow for water and air movement in the soil. But if it just flows overland or goes downhill, the soil picks up whatever kind of contaminants are on the surface and brings that to the waterway.

  While one of the best ways to keep the soil covered is with living plants, Cappellazzi suggests that mulches can help armor the soil so that rain does not hit directly onto a mineral surface. Also, she recommends minimizing soil disturbance by reducing tillage.

How to Conduct a Qualitative Evaluation of Soil Health

  Dr. Jennifer Moore, a research soil scientist for the USDA’s Forage Seed and Cereal Research Unit in Corvallis, Oregon, shared information about the in-field soil health assessment utilized by the Natural Resources Conservation Service (NRCS). This assessment aims to identify if there is a soil health resource concern and then design a conservation plan if needed. In her estimation, conducting an initial assessment helps farmers establish a baseline to monitor when assessing soil health in their vineyard after making management changes.

  Before starting a soil health evaluation, Moore suggests that growers compile a list of past, present and future management goals. They must also consider the prior land use and different soil types. Moore notes that doing the necessary homework and taking notes can help growers track their progress over time. To help with this evaluation, NRCS has a suite of questions they typically ask the landowner to assess soil health: 

•    What is the current crop rotation/cover crop used in inter-rows? 

•    What is the tillage system?

•    How frequently is the implement used, and at what depth?

•    How long have you been in this management system?

•    Are you considering any changes?

•    How many months per year is the surface covered with at least 75 percent of living vegetation, decaying residues or mulches?

•    If the land is grazed, what type of animals and cover crops are on this land? Are these animals and crops a consistent part of the system, and if so, how many years have they been in place?

•    What’s the method and timing of planting and termination periods for the cover crops? 

•    Are there any issues on the field, such as too little water? 

  Ideally, this evaluation should be conducted on moist soils close to field capacity, such as a few days after a saturating rain once the soil has drained appropriately.

  To get an accurate long-term assessment of the soil, farmers should sample soils multiple times during the first year or two to get an idea of how sampling time, moisture, and temperature impact results. Also, the growth stages of the grapevines and the cover crops being evaluated offer insights into how management practices impact soil results. When conducting soil assessments, farmers must be mindful of extenuating circumstances, such as fires, heat waves and floods that can harm the soil. 

Vineyard Soil Health Trials

  Dr. Miguel Garcia, a sustainable agriculture program manager at Napa Natural Resource Conservation District (NRCD), and Cappellazi summarized data from vineyard trials in the California North Coast and the Willamette Valley, respectively. 

  Garcia conducts research with the North Coast Soil Hub, which is a collective of NRCDs from Napa, Sonoma, Mendocino and Humboldt counties. His project involves 500 soil samples from 70 different vineyards throughout these counties. The goal was to develop a tool to showcase how different management practices affect soil health. As these trials were only collected once, they only provide a snapshot of what’s happening with the soil. In order to truly understand how different soil management practices affect soil health over time, longer-term monitoring is necessary.

  The first trial described by Garcia was the long-term project at Huichica Creek Sustainable Demonstration Vineyard, which is owned and operated by the Napa Resource Conservation District and used for educational purposes. Since 1992, half the rows have been tilled, and the remaining rows left undisturbed. For this experiment, they applied a combination of compost and biochar as a soil amendment to select plots that consisted of tilled and no-till rows. A control plot had nothing applied. Over a three-year span, they observed less water pounding and better cover crop growth in those plots that received compost and biochar. Also, they measured an increase in organic carbon and total nitrogen in the no-till and compost plots.

  The second trial was at Gamble Ranch, a no-till vineyard located in the Yountville AVA that is owned by Treasury Wine Estates. Here, they applied compost only. In one section, they experimented by having some of the rows tilled lightly. While this trial continued for several years, preliminary results indicate that the aggregates from the no-till plots remained intact and were better at holding water than tilled plots. Also, they found that no-till with compost produced higher levels of total nitrogen and phosphorus.

  Shannon Cappellazzi reported on trials conducted in the Willamette Valley. The research points to a practical difference between tillage and no-till, although there is often a lot of overlap in the data.   When testing different cover crop treatments, winter annual cereal grains had the highest average water-stable aggregates. However, as Cappellazzi remarked, “It’s hard to get a really significant difference since there’s so much variability because of these differences in apparent features. I would really encourage people to think about comparing soils within a similar climate, texture and slope.”

  When performing this research, Cappellazzi points to the need to assess the difference by slope, as vineyards are typically on hillsides in the Willamette Valley. “When you are comparing two soils to each other, pair them with a similar type of slope and way that that hill faces. That’s going to allow you to actually determine whether or not the management practices that you’re making are making a difference.”

  Cappellazzi likes to use carbon mineralization or CO2 burst tests to assess soil health. “That carbon is the total amount of food that’s available. You need to know whether or not these microbes are using that food. Then the aggregate stability tells you what they are doing with that food. Are they building those structures and allowing that space for the plants and the roots and the water and the microbes to move around there?”

How Growers Can Perform Their Own Soil Tests

  According to Moore, an in-field assessment can be done with tools that many growers have on hand, though one may want to add a penetrometer, a device that measures soil compaction. Also, Moore recommends carrying around a notebook to jot down notes and taking pictures to illustrate soil status.

  In order to evaluate the soil accurately, one must dig holes in multiple places across the land that’s being evaluated. Soil compaction can be evaluated anywhere with a penetrometer or using a wire test flag to depth. If a wire flag can go into the soil to about 10 inches with relative ease, it is assumed that compaction is not a concern. This evaluation should be conducted on moist soils close to field capacity, such as a few days after a saturating rain once the soil has drained appropriately.

  Using dry soil, one can evaluate soil aggregate stability by doing a slake or a slump test. This can provide a quick snapshot of the soil’s overall health. This can be done with simple tools, including a cup and strainer. Get the soil clod wet, and then flip it over. The more the soil retains its shape, the better the aggregate stability and, typically, the more organic matter the soil has.

  One of Cappellazzi’s favorite infield tests is the infiltration rate test which uses a six-inch piece of PVC placed one inch into the soil. Simply filling the column with water allows growers to see how long it takes to get into the soil. If it pools or takes a long time, there may be less soil structure and more compactness, indicating a less healthy soil condition.

The Till Versus No-Till Debate

  Garcia avoids making broad generalizations, citing that an analysis has to be site-specific. “The management practices that you implement, the type of tillage, the kinds of organic matter, the soil and slope of the vineyard, the climate and other factors are driving the change,” he said. “That’s why I like to see soil samples from an individual site.”

  When asked about till versus no-till, Garcia suggested staying away from extremes. “It’s a little bit problematic because tillage could be a valuable tool, assuming that there’s a good reason for doing it and you’re aware consequences to what you’re doing,” he said.  For example, he supported a light pass less than three inches depth in those instances where a grower needs to grow a cover crop on difficult soil. He cites recent evidence that growers can accomplish their objectives with strategic tilling. “When you have high compaction and tried everything you could do to counteract that, then sometimes a light till might be a lifesaver. I think the problem is when we abuse these kinds of techniques and overdo it.”

By: Annie Klodd, University of Minnesota Extension

As the viticulture industry grows in the northern US, beginning growers should be aware of special considerations when pruning in cold climates. Between the risk of cold injury and the trial and error of managing new varieties, growers in this region have adopted a more nuanced approach to pruning.

  Dormant pruning is not only a necessary management step in the northern US – it is also an opportunity to cut out winter damaged wood and make way for more productive cordons.

  In the northern US, pruning takes place between late December to early April, with most growers pruning between February-March. Waiting to prune until February allows you to evaluate winter injury before deciding how aggressively to prune. Crews can also prune more efficiently and effectively in slightly warmer temperatures.

  Pruning in January may be uncomfortable, temperature-wise. On the other hand, it gives the pruning wounds time to dry and close before spring, helping them resist grapevine trunk disease infection.

Reasons We Prune

  Without pruning, grapevines would produce a huge amount of foliage, but low quality, underripe fruit. Pruning limits the amount of foliage and fruit clusters on the vine. This promotes high quality fruit that ripens evenly.

  Grape berries also need some, but not too much, direct sunlight to ripen. Limiting the number of canes on the vine helps sunlight reach the grapes so that they ripen correctly. Pruning also increases airflow through the vines. This helps them dry off after rain, reducing disease problems.

  In the first two to three years after planting a vineyard, growers in cold climates must evaluate winter damage to young canes and train them onto the trellis system as they become strong enough. 

  Foliar, fruit, and trunk diseases infect all grapevines in northern climates with regular summer rainfall. We also tend to see plenty of trunk disease in this region, as winter injury-induced cracking serves as one entry point for grapevine trunk disease.

  However, grapevine trunk diseases can also enter the vines at pruning wounds, and are active once temperatures rise above freezing. Pruning in the winter during freezing temperatures has been shown to reduce the spread of trunk diseases.

Basic Steps to Pruning Cold Climate Vineyards

1.  In the first 2 years after planting grapevines, prune canes back to living, pencil-thick wood. Secure wood to the posts and trellis wire to create trunks and cordons

2.  Remove dead cordons and dead trunks

3.  Replace dead cordon wood with healthy one-year old canes

4.  Remove excess canes completely – each fruiting spur should have just one extension each year

5.  Cut each remaining one-year-old cane down to just 1-4 buds, depending on winter bud injury

6.  Remove suckers unless using them to establish a new trunk

Pruning and Training New Grapevines

  Training the grapevine refers to the process of forming the trunk and cordons of the vine, and securing them to the trellis poles and wire with tape.

  The training step takes place in the first 1-2 years of the vineyard. Slow-growing vines in drought or poor soil conditions, or those that were severely winter-injured after the planting years may take up to 3 years to train.

  First, choose whether you want one or two trunks. In cold climates, some growers choose to train two trunks, in case one succumbs to winter injury. A handful of northern growers even use a 4-trunk system, although this should only be done if deemed necessary after getting to know how your varieties perform in your vineyard.

  Next, choose the strongest 1-4 suckers and tie or tape them snuggly to the bamboo or rebar pole. Cut the selected canes at the point where the wood becomes thinner than a pencil. If no canes are thicker than a pencil, cut each cane back to 2-3 buds. Wait for new shoots to grow back stronger the next summer.

  The next step is to establish cordons. In a northern climate, a couple of different scenarios may play out when establishing cordons.

  If the suckers you used for the trunk are still at least pencil-thick past the top of the post, you may choose to bend the top of the canes downward and tie them to the wire in either direction. These becomes the new cordons. Make a cut where the wood becomes thinner than a pencil. The next season, another shoot should form from a bud near the top of the trunk. Bend it down along the wire in the second direction, to become the second cordon.

  Alternatively, cut the trunk at the top of the post (at or near the level of the wire). The next season, shoots will grow from buds near the top. Choose two of them, and tie one in each direction along the wire, forming the cordons. Make a cut about 12 buds down the cane, or when the cordon becomes thinner than a pencil. If the cordon did not reach its full length, finish it the follow season by tying down a cane toward the end of the cordon.

Remove Dead or Dying Cordons & Trunks

  In cold climates, even the hardiest grape varieties can be injured by extreme temperature drops. Injuries are more common following droughts or early freezes the previous fall. Cold injury is also more common in wet, low-lying areas, so it is not advisable to grow grapevines in those areas.

Cold-injured grapevines may exhibit dead cordons and trunks. However, it is very common for the cordons to remain partially alive but have areas with dead buds and spurs.

Remove and replace cordons that have blind wood for more than one linear foot. Replace the cordon by selecting a strong, healthy one-year old cane from the base of the cordon (or near the top of the trunk) and bending it down to the wire. Tie or tape it to the wire, establishing a new cordon.

  When pruning in very cold temperatures, bending down a vertical cane may tear it. If so, wait to tie it down until temperatures rise above freezing, when it is more flexible. If most of the grapevine has stopped producing fruit and new canes, or if the cordons are dead, it is best to remove the entire trunk. Let suckers grow up from the ground and re-train the entire vine, or dig up the roots and plant a new vine.

Fruiting Spurs

  The cordons of cold climate hybrid grapes have fruiting spurs every 3-5 linear inches. The fruiting spurs are formed from the stubs of removed canes. Each year during pruning, we add a small amount of length to each fruiting spur, until they are removed and replaced.

  The year after cordons are established on a young vine, canes will grow from buds along the cordons. During the following dormant season, cut each cane back to the bottom 2-3 buds. The stub left behind is now a fruiting spur. The next growing season, new shoots and fruit clusters will grow from the remaining buds.  Each growing season, one cane grows from each bud on the fruiting spur. During the dormant season, remove all but one of those canes, and prune the remaining cane back to about 2 buds. This stub becomes part of the fruiting spur, making it a bit longer. If the fruiting spur gets too long, opportunities exist to shorten or replace it. Read on for more information.

Removing Excess Canes & Spurring Back Canes

  Typically, each spur will have at least 2 canes growing from it. Select one cane to keep and remove the others. The cane that you keep will then need to be “spurred back” (it will be trimmed back to become part of the spur).

  Keep the strongest cane, indicated by thickness and color. If both canes are equally healthy, keep the cane that is closer to the bottom of the spur. This helps keep the spur short. With the cane that you have selected to keep, make a cut after the first 1-4 buds. Leaving 2 buds per spur is typical. If you suspect winter injury, leave 3 or 4 buds per spur to account for potential bud losses.

Removing Suckers

  Suckers are the canes that grow from the ground at the base of the vine. With own-rooted cold climate hybrid grapevines, the suckers have the same genetics as the rest of the vine. Therefore, growers using own-rooted, ungrafted hybrid grapevines can use suckers to train up new trunks if the vine needs replacement.

  If no suckers are needed, simply cut them off as close to the ground as possible. This is a good task for older kids; it gets them involved in pruning and is easier than the other steps.

Example Timeline for Pruning New Grapevines

Spring-Summer 2022: Plant grapevines, let the canes grow

Winter 2023: Prune back canes to healthy wood

Summer 2023: Grow and train the best canes to form trunks and cordons

Winter 2024: Trim back cordons to healthy wood

Summer 2024: New canes grow from buds along cordons

Winter 2025: Prune canes back to 2-bud spurs

By: Cheryl Gray

Science, by design, is innovation in constant motion.  Such is the focus of an industry driven by the science behind biopesticides that alter what Mother Nature originally intended, redirecting naturally occurring processes to protect wineries and their vineyards.

  Among the companies with this expertise is family-owned BioSafe Systems, headquartered in Connecticut. For the wine industry, BioSafe specializes in solutions from vineyard crop protection to winery sanitation. A branded leader in research, manufacturing and applications of sustainable chemistries for the agriculture industry, BioSafe Systems has spent the past quarter century finding new, innovative ways that offer sustainable means of protecting its customers’ investments.

  Dr. Jodi Creasap Gee of BioSafe Systems has an intensive educational and industry background in the field. She describes her journey through the science of biologicals and organics protecting wineries from the vineyards to production evolved.

  “My dissertation focused on the mechanism of biological control of crown gall in grapes by a non-pathogenic strain of Agrobacterium vitis. After a brief post-doc studying Erwinia amylovora, I spent five years as the viticulture extension educator for a Cornell Cooperative Extension regional program in Western New York. There, I worked primarily with juice grape growers to improve efficiency, vine health and yield (quantity and quality). From there, I led the Kent State University – Ashtabula Wine Degrees Program as the program director, which also was a dual role with the Viticulture and Enology Science and Technology Alliance as the Ohio representative. Adding in my time spent working at my grandfather’s vineyard when I was a teenager, most of my life has been spent thinking about and working with grapevines.”

  Dr. Gee dually serves as BioSafe Systems’ field research and development project manager and agriculture technical sales representative for the Northeastern United States. She describes some of the company’s products, their applications and how biologicals and organics play a key role in making wine.

  “We work every day in research and development to find new, innovative ways that offer sustainable means of protecting our customers’ investments. Our viticulture and enology customers range from small to large operations using OxiDate 5.0 in the vineyard and SaniDate 5.0 in the winery. Many eastern (U.S.) vineyards regularly use OxiDate 5.0 to control bunch rot later in the season and to control and clean up powdery mildew infections on leaves. Using a broad-spectrum fungicide/surface disinfestant like OxiDate 5.0 in the vineyard reduces a large swath of fungal pathogens and their isolates on leaves and clusters, thereby reducing the likelihood of fungicide resistance. Additionally, biologicals deliver another mode of action for disease management in the vineyard and prevent fungicide resistance.

  Two of our materials fit especially well into a viticulture spray program: OxiDate 5.0 and PerCarb. OxiDate 5.0 can be tank-mixed with many conventional, and biological pesticides, and PerCarb is an excellent rotation partner. Together, these two materials can clean and protect grapevines and clusters, leading to higher quality fruit for excellent wines.”

  For BioSafe products that are designed for use inside wineries, Dr. Gee adds that the company has several solutions for problems that can easily threaten wine production and its preservation.

  “The winery is where the magic happens, and the winery is where high quality fruit can potentially be ruined by spoilage microorganisms, such as Brettanomyces and acetic acid bacteria. Our GreenClean alkaline cleaner used with our BioFoamer foaming agent gets into the nooks and crannies around the winery. For hard surfaces and non-porous sanitizing, SaniDate 5.0 is an excellent option for keeping tanks, floors, walls and lines clean. Finally, in the tasting room, because chlorine is the enemy of good wine, BioSafe Systems carries SaniDate sanitizing wipes for cleaning bars and tables, as well as our SaniDate RTU for end-of-day cleaning.”

  On the West Coast is Pacific Biocontrol Corporation, headquartered in Vancouver, Washington. The company, in business for 35 years, considers itself one of the original pheromone companies and a global player in the science of manipulating naturally occurring pheromones. 

  Pheromones are chemicals emitted by organisms that allow them to communicate among the same species. These chemicals serve many functions, including finding food sources, detecting potential dangers and locating a potential mate. It is the latter that most interests Pacific Biocontrol, according to Jeannine Lowrimore, the company’s technical sales representative for Northern California.

  “PBC’s mission is to increase the use of its mating disruption formulations by developing efficacious products and educating growers on how a pheromone program can impact production. We work with academia, industry and growers to establish regional pest management programs where pheromone mating disruption benefits entire communities. Our fruit and nut customers range from small family ranches to large production farms mainly throughout the Western United States.”

  Lowrimore, with a B.S. degree in entomology from UC Davis and over 20 years of pheromone experience, joined Pacific Biocontrol in 2014. Her expertise in the science of mating disruption through manipulating pheromones includes 15 years as a research assistant for a UCCE Walnut farm advisor, where she worked to effectively develop codling moth mating disruption in walnut orchards.

  Lowrimore says that Pacific Biocontrol provides multiple products for wineries using the same kind of science. Among those products is ISOMATE® VMB, which is used to manage insect pests by interrupting their mating behaviors. Lowrimore explains the process along with the research and development behind the product.

  “Mating disruption works by saturating the field with a synthetic pheromone formulation which keeps the males from finding the females and thus reducing mating and egg laying. The ultimate goal of a mating disruption program is the long-term population decline of that pest. This, in turn, brings an economic benefit to the grower by having to treat less for that pest.

  ISOMATE® VMB was registered in California in May 2021 after several years of extensive research in the Lodi and Napa regions. We also collaborated with Dr. Kent Daane of UC Berkeley in table grape trials in the central San Joaquin Valley. As VMB (vine mealybug) has become a critical pest in California vineyards, giving growers another tool in the battle was extremely welcomed. For organic growers, this challenge is greater without conventional chemistries to lean on. The honeydew and sooty mold caused by VMB infestations contaminate fruit and can impact quality. VMB activity can be detected from early spring months all through the fall and more so in warmer climates. For this reason, ISOMATE VMB was developed to release all through this extremely long season.

  One of the most crucial and largest flights of VMB occurs late October-November when growers are wrapping up harvest activities and not thinking about pest management. Our dispenser has proven longevity to disrupt this flight which then aids in reducing the population going into the following season. For the Lodi and Napa regions, where evenings are cooler, dispensers easily release pheromones for over 200 days. These dispensers quickly twist onto a cordon or trellis wire, are discrete in color and stay secure through mechanical harvesting. We want dispensers to stay in the vines for the remainder of the season and not end up in the fruit.”

  Lowrimore adds that ISOMATE VMB is OMRI (Organic Materials Review Institute) listed and CCOF (California Certified Organic Farmers) approved.

  “Products are non-toxic and environmentally safe and when used in integrated pest management (IPM) programs, ISOMATE® can suppress pest populations while conserving beneficial species. This approach can reduce the need for conventional pesticides and limit the development of pest resistance. More ISOMATE® results in less pesticide residues.”

 Lowrimore says that Pacific Biocontrol Corporation has a diverse pheromone product portfolio targeting the pests of vineyards and fruit and nut orchards. The company, she adds, sells its products through agricultural chemical distributors and dealers worldwide, with customer service a top priority. That means helping clients understand the science and expertise behind the products.

  “We realize educating growers and consultants on the benefits of mating disruption helps reassure them of the investment they’ve made. We also pride ourselves on excellent science in the development of products that are efficacious and economical for growers. Understanding insect pest behavior is crucial for mating disruption programs to have the strongest impact on populations. 

  Our staff is predominantly composed of technically trained and experienced entomologists with advanced degrees, who have worked in academic or government-related pheromone research prior to joining PBC.” 

  Another company among the best in helping wineries protect their grapes using is Suterra.

In business for more than 30 years, the Oregon-based company produces hundreds of products that are used in agricultural regions across the globe, including more than 400,000 acres in California.

  Suterra manufactures its CheckMate® VMB-XL, a membrane dispenser, and CheckMate® VMB-F, a sprayable microencapsulated formula. The products target vine mealybug (VMB), a highly efficient vector of Grapevine Leafroll Associated Viruses. The active ingredient in both products is synthetic replicas of the vine mealybug’s sexual reproduction pheromone. These products limit reproductive capacity, lowers populations and reduce direct crop damage caused by the pest. 

  The use of biologicals and organics in protecting wineries, their fruit and their products is a plan of defense built exclusively around science. Innovation in this industry is as perpetual as the threat of existing microorganisms, as well as those yet to come. Leaders in the industry know this, which is why their expertise is essential, and the depth of their experience in research and development is key.

By: Gerald Dlubala  

It’s not only wine drinkers that look forward to tasting your offerings. Vineyard pests are consistently looking for a handout, and although they are reliable, repeat consumers, they are not your ideal customer. Problematic pests will attack your grapes using any and all available pathways. Professionals agree that whether they arrive at your vineyard by land or air, the best way to control or limit the damaging effects of predatory pests in your vineyard is by adopting proactive methods to effectively stop their intrusion before it begins. Preventative pest deterrent systems implemented on a consistent schedule always have the highest success rates. Luckily, effective pest deterrence methods to thwart the most common offenders can be easy on you without affecting the quality, taste, texture or fermentation abilities of your grapes.

  While trying to halt the invasion of ground-traveling threats like foraging deer, a quality fence system successfully keeps them on the outside while your vineyard thrives on the inside. To protect your vineyards from ground predators, contact a professional to discover what type of fencing solution is best for your vineyard and landscape configuration.

Quality Fencing Keeps Your Vineyard Safe from Hungry Predators: Trident Enterprises

  “Trident Fence specializes in deer and wildlife fencing solutions for numerous applications, including vineyards and wineries,” said Mark Dayhoff, Chief Operating Officer for Trident Enterprises. “Our fencing materials are constructed of heavy-grade polypropylene or PVC-coated metal and are available in six-to-eight-foot heights. We also carry the more traditional fixed knot/field fence options for those that prefer that style. When focusing on deer for vineyards and orchards, we recommend the fencing to be seven and a half to eight feet tall for maximum effectiveness. However, some clients install fencing as high as 10 feet for added protection and peace of mind.”

  Vineyard owners or managers will always want to get a custom quote for their wildlife exclusion fencing, including their preferred height requirements. The fencing choices available from Trident include polypropylene options, 14-gauge PVC-coated welded wire, 20-gauge steel hex and 12.5-gauge field fencing. In addition, all fencing materials can be attached to matching posts provided by Trident or wooden posts under certain circumstances.

  Dayhoff tells The Grapevine Magazine that while they do not do in-person consultations with their clients, they treat each winery and vineyard uniquely, going over the different options in detail with winery personnel to come up with the best choice for success.

  “Frequently, we receive plots or detailed landscape drawings from the wineries,” said Dayhoff. “Using that information, we work up an itemized quote based on the unique needs of the vineyard owner, along with our recommendation for the best choice. Additionally, we’ll use video chat to meet with the client and get a real-time look at the area of the proposed fence installation to see the landscape and any trouble spots or specific areas that need additional discussion or planning. We can also video chat for any issues that come up along the way.”

  Dayhoff says that Trident’s fencing is designed to be installed without needing a separate installer, saving the vineyard owner money. In addition, no specialized tools are required for the polypropylene, steel hex or welded wire fencing systems. Most installations are completed using standard tools, like sledgehammers, drills and wrenches. The only exception is Trident’s fixed knot fence, which is a bit more complex to install. Installation for a fixed knot fence may require the use of tensioners, tractors or miscellaneous heavy equipment to complete the installation. Expected lifespans range from 15 years for their polypropylene options to 30 years for metal fencing, depending on the thickness of the wire chosen by the customer.

  “The thing to remember is that it’s important to act early for maximum success with deer fencing,” said Dayhoff. “Our fencing works best when installed before you have a deer problem, so when the deer initially encounter the fence, they won’t attempt or think about jumping over or going through it. Instead, they’ll walk the perimeter of the fence and head off searching for the next, more accessible food option. If the deer are already accustomed to coming into the vineyard, you’ll have to correct their feeding habits to get them to look elsewhere. That will take a little longer, and a few may initially still get in during the process. Consistently checking and inspecting the fence line for breaches or breach attempts by wildlife will show the areas that need strengthening and reinforcing to keep the deer from getting through. Over time, the deer will establish a new trail outside the fence line in search of a different food source. It’s always easier to keep them out from the start rather than training them to go elsewhere for their food source.”

  As expected, pricing for deer fence systems varies based on the vineyard’s size, landscape and needs, along with the vineyard owner’s choice of fencing material and unique configuration needs, including gates, corners and ends. The overall cost is different for every application and situation, so Dayhoff suggests that it is always beneficial for the vineyard owner or manager to call to obtain a definitive and accurate quote rather than relying on estimates and hypothetical situations. One size never fits all.

  “We have all the parts and accessories a vineyard owner or manager needs to create an effective wildlife exclusion fence to keep deer and other crop-damaging wildlife out of their vineyard,” said Dayhoff. “We will provide the proper materials, including the fencing, posts, corner, ends and necessary gates needed for complete and effective installation. Along with fencing, we can also supply the vineyard with options in full lines of bird and trellis netting to help and aid in other areas of vineyard and winery pest control.”

Bird Is the Word: Avian Enterprises

  Now that you have the land-based wildlife held at bay, you must also consider the air attack that can destroy and decimate your vineyard. Bird problems can get out of hand quickly. With abundant food and cover, there’s no better place than a vineyard for nesting birds to call home. Like fencing installations, getting an early jump on a potential bird problem in your vineyard is critical before it becomes a legitimate, more significant problem.

  “You always want to be proactive and start weekly applications before you have a full-blown problem,” said Jon Stone, president of Avian Enterprises LLC, which offers simple solutions to bird problems across many industries. “For best results, we recommend early applications of Avian Control® for Crops before the scout birds can come in and set up residence.”

  Avian Control® for Crops is a biological pesticide that protects your crops from bird damage by reducing or eliminating bird nesting in your vineyard and surrounding property, thereby reducing or eliminating harmful bird droppings on the plants along with the loss of crops from birds feeding on them. Avian Control® repels only birds. There is no effect on humans or domestic animals. It’s proven effective at significantly reducing bird predation on both wine and table grapes, as well as many other crops.

  “Avian Control® is a Methyl anthranilate (MA)-based repellent that negatively stimulates the trigeminal nerve located in the bird’s head. This unpleasant or uncomfortable sensation subsequently urges the bird to go elsewhere for nesting purposes,” said Dan Kramer, technical director of Avian Enterprises LLC. “Methyl anthranilate is a naturally occurring ingredient found in bergamot, black locust, gardenia, jasmine, lemon, mandarin oranges and strawberries, and it features a chemical formula comprised of carbon, hydrogen, nitrogen and oxygen, all essential life elements. It, along with all the ingredients in Avian Control®, is completely biodegradable and widely used in foods designed for human consumption. All ingredients formulated in Avian Control® are food-grade and generally recognized as safe (GRAS) within the food industry while providing growers with affordable, easy-to-apply repellents that reduce or eliminate the need for additional netting, noisemakers and inflatables. Additionally, when MA biodegrades, it breaks down into the simple elements of carbon, hydrogen, nitrogen and oxygen, all found naturally in grapes and produced in small quantities in several V. vinifera cultivars, including pinot noir, riesling and silvaner.”

  The current Avian Control® repellant is a third-generation product designed to repel birds for up to 14 days without affecting the treated grapes’ appearance, taste or fermentation abilities as some other bird-repellent products are known to do. The patented formula provides a strong effect without harming the birds that come into contact with it. Additionally, the birds cannot acclimate or become immune to it, so with the regular use of Avian Control®, the birds are effectively being trained to stay away.

  “The best results occur when Avian Control® is mixed with water of pH7 or higher,” said Stone. “Avian Control® can be used all over a winery’s property and is easily and effectively applied through equipment that the vineyard likely has on hand, including air blast, boom and handheld sprayers or through shoulder mount foggers. Along with the vineyards themselves, it’s also beneficial to use Avian Control® in nearby barns, pavilions, sheds or any place where birds tend to congregate. You want to get in those places and fog rafters at least once a week or more frequently for the first two weeks to get ahead of the scouting birds. Consistency is the key to success, so after the initial application, we recommend a weekly schedule to keep things fresh and most effective. The recommended application schedules can change with weather conditions, particularly in rainy conditions, where the application may have to be reapplied more frequently to remain effective.”

  “Avian Control® Bird Repellent provides the vigneron with a bird control technology that repels feathered pests, is easy to apply and economical, is not phytotoxic and has no impact on the fine wines produced from treated grapes,” said Kramer.

  An application of Avian Control® can cost a vineyard as low as $12.50 an acre and last up to two weeks in normal conditions. The length of effectiveness is even longer when used in indoor structures.

“I can’t stress enough that proactive, consistent application at strong enough rates is key,” said Stone. “Use this approach, and you will succeed in keeping birds away from your vineyard.”