Trunk Neglect Is Too Common

riesling grapeTrunk or wood-canker diseases, including Botryosphaeria dieback, Esca, Eutypa dieback, and Phomopsis dieback, present a serious challenge to winegrape growers. Many vineyards in California are likely infected and yield losses in severely symptomatic vineyards can reach more than 90%. The overall economic impact of losses to Eutypa alone just in California has been estimated at 14% of gross producer value.

Trunk diseases take a long time to develop and often become symptomatic years after infection has already occurred, at which point management options are limited. While preventative management practices are available, grape growers may be hesitant to use them due to uncertainties about cost-effectiveness and future risk of infection.

Key Findings
Grape growers in the southern San Joaquin Valley, predominantly raisin growers in Fresno County, use both delayed pruning and pruning-wound protectants at relatively low levels for the prevention of trunk disease. For both practices, almost 40% of growers begin using the practice in vineyards older than 13 years. Growers rated pruning-wound protectants slightly more positively than delayed pruning for both maintaining yield and cost-effectiveness.

Methodology
We conducted a survey of attendees at the San Joaquin Valley Grape Symposium, organized and hosted by Matthew Fidelibus, University of California Cooperative Extension Specialist, held in Easton, CA, on Jan. 8. We used Turning Point, an electronic audience response system, to conduct the survey. UCCE Viticulture farm advisors and industry representatives helped design the survey. Up to 67 individuals responded to any given survey question.

Similar surveys are being conducted in other grape growing regions of California in the winter of 2013-2014. We are also conducting economic cost-benefit studies to better understand the long-term costs and benefits of different management practices in a range of scenarios. Combined, this research will provide us with a better understanding of the long-term efficacy of these management practices and the incentives motivating grower decision-making. We hope that this information will, in turn, provide growers and other managers a better understanding of how best to deal with trunk diseases.

trunk-neglect-figure-1-and-2Detailed Results
We asked raisin growers from the southern San Joaquin Valley about two practices known to be effective in preventing trunk diseases: delayed pruning and the application of pruning-wound protectants. We first asked growers how often they have used — or advised, for those in an advisory role — each of the practices in the last five years. As seen in Figure 1, growers use both delayed pruning and pruning-wound protectants at relatively low levels. Between 50-60% of growers never or rarely use these two practices.

We also asked growers what the typical age of a vineyard was when they first started using each (or advising) of the practices. Because these practices are most effective when used as preventative measures before infection occurs, the age of the vineyard at first use is an indication as to whether the practices are being used optimally. Symptoms typically become apparent in vineyards eight years or older, even when infection occurs much earlier. As seen in Figure 2, for both practices, about 40% of the growers reported typical first use to be in vineyards older than 13 years old. Thus a sizable minority of growers likely start to use these preventative practices after infection has already occurred.

trunk-neglect-figure-3Finally, we asked growers to evaluate the efficacy of each of the practices for two different criteria: maintaining adequate yield and cost-effectiveness. As seen in Figure 3, growers rated both practices mildly positively for both characteristics. Growers rated pruning-wound protectants slightly more positively than they did delayed pruning.

Topics: , , ,

Leave a Reply

Fruits Stories
Farm ManagementGenNext Growers Taking Marketing To The Next Level
July 7, 2015
In part two of our Marketing Tips From 14 GenNext Growers feature, we conclude with the remaining marketing and branding Read More
Agritainment
CitrusAgritourism Gaining Lots Of Ground In Sunshine State
July 6, 2015
Researchers report more farming operations are growing revenue by hosting festivals, tours, wine tastings, and more. Read More
Photo of New Guinea flatworm found near Coral Gables, FL
CitrusSouth Florida’s Newest Pest Has Significant Ooze Factor
July 2, 2015
The infamous New Guinea flatworm, one of the ‘world's worst invasive alien species,’ might have found a new home. Read More
Farm ManagementPMA Advocates For Improvements To Proposed FSMA Mandatory Food Recall Guidance
July 2, 2015
This week the Produce Marketing Association (PMA) submitted comments on behalf of its membership to FDA regarding the proposed Mandatory Read More
CitrusFlorida’s Young Farmers Working To Bridge Generation Gap
July 2, 2015
Leadership conference to give GenNext Growers tools to become better agvocates. Read More
Business PlanningTake Climate Change — Please [Opinion]
June 30, 2015
It’s a difficult issue because people tend to think of it in terms of something tangible — like the weather. Read More
FruitsHighlights From The Ohio Produce Growers And Marketers Summer Tour [Slideshow]
June 30, 2015
American Vegetable Grower magazine made its way to the Ohio Produce Growers and Marketers Association (OPGMA) Summer Tour & Field Read More
The Latest
FruitsStudy: Stink Bugs Track Favorite Fruits Through Growing…
July 7, 2015
The brown marmorated stink bug has a bad reputation. And for good reason: every summer, this pest attacks crops causing Read More
FruitsNew Research Shows Spotted Wing Drosophila Repellent Na…
July 7, 2015
Spotted wing drosophila, Drosophila suzukii, is a big pest for fruit growers. However, Christine Krause Pham and Anandasankar Ray, researchers Read More
CitrusNew York Representative Introduces Bill To Help Young G…
July 7, 2015
The Young Farmer Success Act of 2015 was recently introduced by U.S. Rep. Chris Gibson, R-NY, and  U.S. Rep. Joe Read More
Farm ManagementGenNext Growers Taking Marketing To The Next Level
July 7, 2015
In part two of our Marketing Tips From 14 GenNext Growers feature, we conclude with the remaining marketing and branding Read More
Agritainment
CitrusAgritourism Gaining Lots Of Ground In Sunshine State
July 6, 2015
Researchers report more farming operations are growing revenue by hosting festivals, tours, wine tastings, and more. Read More
Photo of New Guinea flatworm found near Coral Gables, FL
CitrusSouth Florida’s Newest Pest Has Significant Ooze Factor
July 2, 2015
The infamous New Guinea flatworm, one of the ‘world's worst invasive alien species,’ might have found a new home. Read More
Farm ManagementPMA Advocates For Improvements To Proposed FSMA Mandato…
July 2, 2015
This week the Produce Marketing Association (PMA) submitted comments on behalf of its membership to FDA regarding the proposed Mandatory Read More
CitrusFlorida’s Young Farmers Working To Bridge Generation Ga…
July 2, 2015
Leadership conference to give GenNext Growers tools to become better agvocates. Read More
Business PlanningTake Climate Change — Please [Opinion]
June 30, 2015
It’s a difficult issue because people tend to think of it in terms of something tangible — like the weather. Read More
FruitsHighlights From The Ohio Produce Growers And Marketers …
June 30, 2015
American Vegetable Grower magazine made its way to the Ohio Produce Growers and Marketers Association (OPGMA) Summer Tour & Field Read More
Apples & PearsWildfires Damage Washington Fruit Businesses
June 29, 2015
More than 1,000 people have been forced to evacuate as a fast-moving wildfire swept into Wenatchee, WA, on Sunday night Read More
Farm ManagementMarketing Tips From GenNext Growers
June 29, 2015
Whether your business is in its beginning stages of development or is already established and in need of increased visibility, Read More
USDA organic logo
Farm ManagementThe ROI On An Organic Checkoff [Opinion]
June 29, 2015
Organic agriculture is more profitable for farmers than conventional agriculture, according to a recent study published in the Proceedings of Read More
Crop ProtectionStay A Step Ahead Of Weeds
June 26, 2015
Weed control can be a tricky and costly task made all the more difficult by herbicide resistance and the push Read More
Fumigating strawberries
FruitsThere’s More Than One Way To Nix Nematodes
June 25, 2015
Compare and contrast these five nematicide products to find out what's the best fit for your farm. Read More
money down the drain
CitrusGovernor’s Budget Veto Likely To Shutter UF/IFAS …
June 25, 2015
A $180,000 increase, plus another $720,000 in funding for program gone in the stroke of a pen. Read More
FruitsHow To Make Social Media Work For You
June 25, 2015
I have a confession to make. I enter a lot of contests. I’ve won gift cards to local restaurants, locally Read More
Farm ManagementIndustry Experts Sound Off On Climate Change
June 24, 2015
Growers and stakeholders share their thoughts on what they see is happening in the environment, and what you might be dealing with in the future. Read More