Management of with Various Miticides and Insecticides and Their Toxicity to Predatory Mites Conserved for Biological Mite Control in Eastern U.S. Apple Orchards.

(Koch) (Acari: Tetranychidae), commonly known as European red mite, is a polyphagous pest of various tree and small fruit crops, including apples. A field study was conducted to evaluate different pesticide options available for the management of , and their impact on the population of non-target predatory mite species complex consisting of , , and in apple orchards. Pesticides were applied using a commercial airblast sprayer at the 3-5 mite/leaf recommended economic Integrated Pest Management (IPM) threshold or prophylactically in the spring ignoring IPM practices such as monitoring, reliance on biological control and economic thresholds. Effects on the motile and egg stages of were evaluated as were effects on the populations of predatory mites through frequent leaf counts during the season. We also recorded the subsequent overwintering eggs of from each pesticide treatment. The two prophylactic treatments containing a mixture of zeta-cypermethrin + avermectin B1 + 1% horticultural oil and abamectin + 1% horticultural oil provided effective control of population throughout the season without reducing predatory mite populations. In contrast, eight treatments applied at the recommended economic threshold of 3-5 mites/leaf were not effective in suppressing populations and most reduced predatory mites. Etoxazole had significantly higher number of overwintering eggs compared to all other treatments.