Integrated Pest Management for Varroa Destructor in the Northeastern United States using Drone Brood Removal and Formic Acid

This bulletin focuses on the management of the parasitic honey bee mite Varroa destructor (V. destructor) in the northeastern U.S. It contains information that will allow a beekeeper to: 1) identify V. destructor, 2) recognize the symptoms of mite infestation, 3) determine pest densities, and 4) implement an effective IPM program for keeping mite populations below the economic injury level.

The western honey bee, Apis mellifera, was introduced to the U.S. from Europe in the 1600s. Today, the honey bee provides essential pollination services for over 45 commercial crops grown throughout the U.S., adding $14.6 billion to the value of the country's agricultural production each year. In addition, U.S. beekeepers produce between 170 and 220 million pounds of honey each year, more than 50% of total U.S. consumption. Hence, a sustainable supply of healthy and affordable honey bee colonies is a critical factor affecting farm productivity and the stability of farm incomes and food prices.

Geographic Adaptability: The methods discussed in this fact sheet were developed and evaluated in the northeastern United States. Drone brood removal will benefit beekeepers throughout the United States; however, formic acid and other miticides acting as fumigants work best in areas where colonies are broodless or nearly broodless for at least four weeks during the fall or winter. When a colony is rearing brood, most mites are present in brood cells where they are protected from the effects of fumigants. During broodless periods, mites are present on adult hosts and are susceptible to fumigants. Since fumigants have a relatively short treatment period (about three weeks) compared to other pesticides (about six weeks), it is critical that the majority of mites be present on adult hosts for fumigants to be effective.

Want more information? See the related SARE grant(s) LNE00-130, Integrating Natural Products & Genetic Resources for Control of Varroa Jacobsoni, a Parasitic Mite of the Honey Bee.