CONTROL OF TWOSPOTTED SPIDER MITES ON TART CHERRY, 2010

This study was set up to evaluate the efficacy of miticides for control of TSSM in tart cherries. The trial was conducted at the Northwest Michigan Horticulture Research Station in Traverse City. One-tree plots were established in a mature block of well-pruned Montmorency tart cherry trees, and treatments then assigned in a RCB design with 4 replications. Test materials were applied at “A” First Cover (26 May) and “B” threshold (4 Aug). All applications were made with an FMC 1229 airblast sprayer calibrated to deliver 60 gpa at 3 mph. A pre count was made on 2 Aug. Post-application evaluations were made on 12 Aug (8 DAA) “Days After Application” 18 Aug (14 DAA), 26 Aug (22 DAA) and 7 Sep (34 DAA). On each date, 25 randomly selected leaves were picked from each replicate, brought back to the lab, and passed through a mite-brushing machine. Motile forms of TSSM and AF were then counted with the aid of a stereo microscope. All mite data are reported as the mean number of mites per leaf. Transformed treatment means were analyzed using ANOVA and means separation by Duncan’s New MRT at P = 0.05.