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can be seen rapidly with dinotefuran and thiamethoxam, but will take more time when applying imidacloprid. Single applications in the spring and in the fall will most likely protect plants through most of the year. Curative Treatments: See the figure below for effective systemic treatments that will work curatively. Applied as a drench, dinotefuran, thiamethoxam, and the combination product with imidacloprid plus bifenthrin worked very well in controlling infestations. In addition, we have noted significant recovery of the plants two months following applications. Results from a Recent Trial: We were able to conduct a trial on a lengthy stretch of Myoporum laetum at the Del Mar Fairgrounds in San Diego County. We divided the stretch of myoporum into 20foot sections (about 5 mature plants each) and randomly assigned treatments to the plots. There were five replicates per treatment. We took 5 terminals from each plot and counted immature and adult thrips. Two months after application, all treatments except abamectin were significantly different than the control (Figure 2). Note that it took an extra month for imidacloprid treatments to take effect, but as a drench and a spray, they were effective at suppressing populations. In addition, the combo product of imidacloprid plus bifenthrin was very effective. The combo product of imidacloprid plus bifenthrin and the trunk application of dinotefuran eliminated the thrips two months after application. Treated plants began to show recovery from the damage beginning three months after treatment application. Plants in the control treatments were severely damaged (Figure 3). Plants treated with a drench application of thiamethoxam were recovering nicely with little deformed leaves or terminals (Figure 4). 

40  December 2010

December CAPCA Adviser  

December CAPCA Adviser

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