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In response to cancellation of Omite (propargite) as the only short-term control for this pest mite on cranberries in 1996, we evaluated seven compounds to determine which warranted further field testing. Forty sweet pepperbush (Clethra alnifolia) leaves were ‘cleaned’ of existing debris using a paper towel wetted with distilled water. Each pepperbush leaf was then placed singly in a petri dish that contained three sheets of filter paper saturated with distilled water to prevent both mite escape and leaf desiccation. Each treatment and the check (water) had 5 replicates. Applications were made with a hand sprayer. Ten adult mites were placed on each pepperbush leaf and were sprayed with a test material to runoff. Covers were then placed on the petri dishes to reduce evaporation. The bioassay plates were placed in a growth chamber at 25& C, with 14:10 LD. Each treatment and check was evaluated for living and dead mites at 1, 3 or 4, and 7 days after treat-ment.

An established commercial cranberry bog in Taunton, MA, was treated with 4 materials under investigation as alternatives to propargite for Southern red mite control. Plots were 1 by lm in size, separated by 20-cm buffer strips, and arranged with five replicates per treatment in a Latin-square design. All treatments were made at 100 gallons per acre and 40 psi with a stainless steel backpack CO2 pressurized sprayer. All plots were treated on 20 Aug, following pre-treatment sample collections. All plots except pyridaben were retreated on 29 Aug. Check plots were sprayed with water only. Evaluations involved examination of 25 uprights per plot for all mite stages under a dissecting microscope, on 20 (pretreatment), 21, 29 (before 2nd treatment), and 30 Aug, 5 and 10 Sep, and on 16 and 30 Sep for untreated check and pyridaben plots only. The bog was flooded for harvest between 21 and 28 Sep.