Vineyard Views & Events
Latest information on viticulture, UC research and newly released UC publications.
|Monitoring and Detecting DMI Fungicide Resistance in Grape Powdery Mildew (343KB)||
Follow the link to the newsletter below for more information on the status of resistance testing for grape powdery mildew for the DMI (FRAC 3) fungicides.
|Inspecting green-growing vines for VMB (22,963KB)||
Vine mealybug has been found on recent nursery shipments of green-growing vines in the North Coast region.
Follow the newsletter link below to learn more. The newsletter can be used as training tool for crews inspecting vines as they are received.
In Napa County, staff of the Agricultural Commissioner inspect all incoming shipments of green-growing vines and nursery plants. If you are expecting a shipment, contact the Agricultural Commissioner's office: (707) 253-4357
|Potential benefits of powdery mildew resistant grapevines (201KB)||
Recent research from the UC Davis Department of Agricultural and Resource Economics evaluated the potential economic benefits to California of powdery mildew resistant grapevines. (See newsletter link below).
As a follow-up to this study, the research team is collecting information on grower preferences for specific traits. We would appreciate if you could take a few minutes to respond to their survey questions: https://okstatecasnr.az1.qualtrics.com/SE/?SID=SV_5AwMOELdrMZ9xJ3
|Walnut Twig Beetle and Thousand Cankers Disease (5,462KB)||
In early September 2015, the California Department of Food & Agriculture confirmed the presence of thousand cankers disease of walnut in Napa County.
Access the newsletter below for additional information on this fungal disease and the beetle that moves it from tree to tree.
|Monitoring Guide for Western Grapeleaf Skeletonizer (1,370KB)||
On June 24, 2015, staff of the Napa County Agricultural Commissioner found one male Western Grapeleaf Skeletonizer in a pheromone-baited trap in a vineyard on Tubbs Lane in Calistoga.
UCCE Advisors Lucia Varela and Monica Cooper developed a "Monitoring Guide for Western Grapeleaf Skeletonizer" so that vineyard owners, growers and workers could familiarize themselves with the pest's life stages and feeding habits.
Please use the newsletter link below to access the Monitoring Guide (English and Spanish versions).
If you find this pest or feeding damage in Napa County please contact the office of the Agricultural Commissioner: 707-253-4357, email@example.com OR contact UC Cooperative Extension: 707-253-4221, firstname.lastname@example.org
For additional information on biology and management of this pest, access the UC IPM Pest Management Guide for Western Grapeleaf Skeletonizer.
|Arboreal Camel Cricket (33,926KB)||
In April, we observed leaf symptoms in select vineyards consistent with feeding damage by arboreal camel crickets.
For photos and additional information, access the newsletter using the link provided below.
|Vine mealybug management and FAQs (10,329KB)||
The Napa County Wine grape Pest & Disease Control District sponsored a seminar on vine mealybug (VMB) on February 25. We discussed VMB detection, biology and management. As a follow-up, this article summarizes significant points from the day, focusing on issues that are of particular concern for management of VMB, and also addresses FAQs
|Grape Erineum Mite (5,526KB)||
The results of grape erineum mite trials in the North Coast region were recently published in the December edition of CAPCA Adviser.
The article includes a monitoring data collected during the fall migration of erineum mites, from galls in grape leaves to from grape leaves to overwintering sites beneath latent bud scales.
It also includes results of a preliminary trial evaluating the efficacy of post-harvest sulfur treatments for control of erineum mite populations, in an early-harvested variety (Sauvignon Blanc).
Follow the newsletter link below to access the erineum mite article.
|Water limiting (drought) conditions (23KB)||
Resources for water management of grapevines under drought conditions (courtesy of our colleagues in Australia) are available in the Irrigation section of the UC Cooperative Extension-Napa County website: http://cenapa.ucanr.edu/Napa_County_Programs/Viticulture/Irrigation/
Considerations for managing vine growth & yield under water-limiting conditions include:
1. Managing crop size through reductions in bud numbers and/or thinning after set. Adjust crop size to predicted water availability.
2. If possible, target supplementary irrigation to critical physiological periods: (a) budburst to flowering, (b) flowering to fruit set, (c) veraison to harvest, (d) harvest to leaf fall--hopefully will be raining by then!
3. Organic residues (from cover crops or weeds) and mulches may moderate soil surface temperatures.
|Virginia creeper leafhopper (1,847KB)||
Update on Virginia creeper leafhopper (VCLH) populations:
Populations of Virginia creeper leafhopper (VCLH) have been identified in Napa County, in Pope Valley.
Follow the newsletter link below for additional information on VCLH and variegated leafhopper populations in Napa, including photos and links to additional training tools. Early detection and identification can be critical to avoiding economic injury.