Vine Mealybug Season Tips: When to apply mealybug treatment?

Want advice on when to deploy mating disruption for vine mealybug and which of our platforms is best for you? Our technical team has several season tips that can help you optimize mating disruption in your IPM program.

Deploying Mating Disruption in vineyards

Growers typically deploy pheromone mating disruption for vine mealybug in the spring. Depending on local practices and availability of labor, deployment can be done before the first flight (April), or just before the second flight (late May). Grower experience shows both strategies can be effective.

Suterra offers CheckMate® VMB-F, a liquid sprayable formulation, and CheckMate® VMB-XL dispensers. The biggest consideration for VMB-XL dispenser deployment is usually availability and cost of labor. 

CheckMate ® VMB-F can be tank-mixed with most foliar-applied spray applications throughout the season as long as the timing is correct to cover critical VMB flight timings. For more information about tank-mix compatibility, contact your local Suterra representative or download the Compatibility Guide.

Field scouts both in the Central Valley and Central Coast areas have reported movement of VMB up the trunk and cordon but not much seen on canes, leaves or buds yet. Mostly seen are young adults and second instar larvae on the trunk, under the bark. A few adult females are forming egg masses. It is time now to plan deployment of pheromone mating disruption for VMB.

VMB overwinters on the lower part of the grapevine under the bark, close to or under the soil surface where it can reside unseen for many months. Growers who are affected by this pest for the first time are often unaware of this and can be caught by surprise as temperatures increase and VMB becomes more active.

Compared to other mealybugs, vine mealybugs are aggressively prolific and can have up to eight overlapping generations and are much more likely to be found on the upper leaves during the growing season than the other mealybugs. During summer when vine mealybugs are in the canopy, they can be located well above the fruit zone and will lay eggs on the leaves, while Pseudococcus mealybugs do not.

Both coastal and inland grape-growing regions of CA have autumn VMB flights after harvest season. These end-of-season flights can set the foundation for a large overwintering population of crawlers, so growers are increasingly seeing a benefit to using mating disruption into October/November to help decrease the number of overwintering VMB which can lower the pressure the following spring.

Which Platform Is Best for My Farm?

CheckMate® VMB-XL dispensers should be deployed at 250 dispensers per acre. The dispenser hanging pattern will depend on vine spacing and the number of vines per acre. Generally, the 250 dispensers should be evenly spread over each acre. Any extra dispensers should be added to known hot spots or field edges.

Frequently Asked Questions

Q: Is there a risk of going over the DO NOT EXCEED level (150g ai/ac per year) with multiple applications of VMB-F or combinations of VMB-XL and VMB-F?

A: No, there is no risk. VMB-F applied monthly from April through October (seven applications at 5 grams of active ingredient per acre) would only reach 35g ai/ac. Combining VMB-XL and VMB-F would still only reach 72.5g ai/ac.

Q: In an ultra-low volume application, can ants eat it or carry it away?

A: No, ants will not take the microcapsules away from the branches.

Q: Where on the vine should CheckMate VMB-XL dispensers be hung?

A: Close to the trunk at cordon height, avoiding direct sun exposure as much as possible. It's preferable to deploy on the north side of the vine.

Q: If a grower has two extra buckets of dispensers, will they still be effective next season?

A: The shelf life for unopened buckets is the season starting two years from the manufacturing date printed on bucket. This means they must be deployed within two years of their manufacturing date. Opened buckets should be used within the season they were unsealed.