Vine Mealy Bug Update Dan Curtin Agricultural Biologist Sonoma County Agricultural Commissioners Office
How to Differentiate Between Mealybugs? Vine Grape Shape: Oblong Rectangular Edge filaments short & wide Edge filaments long & thin Short tails Long tails Photo: Jack K. Clark
Grape Mealybug: long tails grape mealybug Photo: Jack K. Clark 2 generations per year moderate honeydew production native to North America vine mealybug Photo: Kent Daane Vine Mealybug: short tails waxy filaments short and thicker 3-5 generations per year stages overlap throughout year excessive honeydew production feeds throughout the canopy, above fruit zone in the summer lays eggs on the leaves introduced exotic pest
Treatment Thresholds and Treatment Timing Differ: Grape and vine mealybug have different life cycles, which means chemical control timing is different. Grape mealybug is better controlled by its natural enemies, thus chemical control measures are not always needed. Need to avoid the spread of vine mealybug. Early detection is crucial, and if found treatment is recommended.
Vine Mealybug is Spreading Aug 2003
Vine Mealybug is Spreading Oct 2003
Vine mealybug is spreading Prevailing winds Aug 2004 No shared equipment
How does the VMB spread? Natural Spread Wind, Birds. Assisted Spread Field Workers, Equipment, Birds. Important that you do not allow infestations in the canopy as it increases the probability of spread. Follow the UCCE Best Management Practices.
Walt Bentley Kent Daane Natural Spread Mark Battany Avoid infestations in the canopy
crawlers Immatures Adult females
Assisted Spread of VMB
1994: Vine mealybug identified in Riverside County
1998: Kern County
1999: Fresno County
2000: Santa Barbara County
2001: San Luis Obispo County
2002: Monterey, Sonoma, Napa, Sacramento, Yolo, Madera, Stanislaus, El Dorado Counties
2003: San Joaquin, Contra Costa, Alameda, Santa Clara Counties
2004: Tulare, San Benito, Merced, Lake Counties
To Detect New Infestations Monitor Vineyards for VMB Males Photo: Kent Daane
Trapping for VMB When? Start in June you catch low numbers (even in infested vineyards) but can take action well before harvest. Numbers increase from August to November, be aware most chemicals have close to a 30 day PHI. How many? One per 30 acres. Use more traps to zero-in on infestation. How long? Stop in October if traps do not catch VMB. Continue trapping through December (until rainfall &/or cold) if traps catch VMB but infestation has not been found.
If you catch males in your traps Photo: Kent Daane Compare counts with your neighbors
Recognize Signs of Mealybug Infested Vines: Train your employees to: Follow the ants and watch where they go If ants are not present, then look for wet trunks Photo: Rhonda Smith Recognize mealybug life stages on trunks and leaves Look for honeydew and sooty mold Photo: Rhonda Smith
Sanitation practices Power wash machinery Harvest infested field last
Sanitation: Thoroughly rinse inside and outside Macro bins are commonly shared among vineyards and wineries
Compost Standards CA Integrated Waste Management Board 131ºF, 15 days (3 days for static piles)
Promise New biological controls are being researched. Mating disruption pheremone is being researched and produced (pushing for registration). New ant baits are being researched. Awareness is increasing.
Biological control Mealybug egg mass Mealybug destroyer (Cryptolaemus montrouzieri) Mealybug destroyer 1st instar larvae Adult Larvae Photos: Jack K. Clark
Biological control Parasitic wasps Anagyrus spp. prefers larger VMB stages Photos: Kent Daane
UCCE Best Management Practices You should read and follow the Best Management Practices for VMB. Can be accessed at: University of California Cooperative Extension http://cesonoma.ucdavis.edu/viticulture717/mealybugs.htm (The above website also has information for retail sources of VMB Traps and Lure and resources for having your traps read). Sonoma County Agricultural Commissioners Office http://www.sonoma-county.org/agcomm/pest_management.htm
More Information on the Web UCCE Sonoma County http://www.cesonoma.ucdavis.edu UC Pest Management Guidelines http://www.ipm.ucdavis.edu UC VMB website - Kent Daane & Walt Bentley http://vinemealybug.uckac.edu Vine Mealy Bug Workgroup http://www.vinemealybugworkgroup.com/
Vine mealybug What you do not want to see! Mid winter Photos Courtesy of Mark Battany Harvest
In Conclusion: Trap your vineyard. Learn to read your traps, or have someone read them for you. Talk to your neighbors, synchronize applications. Treat early to keep populations low. Know which mealybug you are dealing with. Grape mealybug may not need a postharvest treatment, natural predators are at their highest population. Stay informed.
Dan how are you so knowledgeable about VMB? (Who really constructed this presentation?) Lucia G. Varela University of California Cooperative Extension & Statewide IPM Program Rhonda Smith Viticulture Farm Advisor, University of California Agricultural and Natural Resources, UCCE Sonoma County. Mark Battany Farm Advisor, University of California Agricultural and Natural Resources, San Luis Obispo and Santa Barbara Counties. Division of Agriculture and Natural Resources