Supplemental label issued for Verdepryn to control blueberry stem gall wasp
Michigan growers have an additional tool for controlling this pest.
The new insecticide Verdepryn is a diamide insecticide based on the active ingredient cyclaniliprole. This is already labeled for use in blueberry against cutworms, fruitworms, Japanese beetle, blueberry maggot and other insect pests. The company marketing Verdepryn in the U.S., SummitAgro, has now released an expanded recommendation for this insecticide under FIFRA Section 2ee to control blueberry stem gall wasp. It recommends 8.2-11 ounces per acre, applied twice post-bloom, applied in high gallonage with a penetrating adjuvant.
In 2019, we tested this insecticide against gall wasp in a field of Jersey variety where the bushes were 5-6 feet high, and with about 50 galls per bush in the untreated plots. The plots treated with Verdepryn (two applications at 11 ounces per acre at post-bloom and reapplied seven days later) had none of the large galls and we measured very low emergence from the galls that were formed. This resulted in over 95% reduction in the number of wasps emerging from bushes that were treated with the two applications of Verdepryn.
In 2020, we plan to compare a single post-bloom application, which will also help control fruitworms, to two applications as indicated on the label to see if that is still effective. We are also hoping to gain experience at farms where growers use this product in bushes with larger canopies and on larger scales across their fields.
The 2ee label for Verdepryn must be in possession of the grower if applying it for gall wasp control.