Evaluation of Insecticides Against Cranberry Rootworm, 1995

Insecticides for the control of CRW were evaluated on a bed of ‘Ben Lear’ cranberries near Chatsworth, NJ. Soil type at this site was sandy loam with a pH of 4.0. Treatment plots were 6-ft by 6-ft arranged in a CRD. Each treatment was replicated 5 times. A buffer strip of cranberries at least 1-m wide was maintained around each plot. Diazinon 14G was applied by spreading the granules evenly by hand. Liquid formulations were sprayed targeting the ground with a CO2 pressurized Model T backpack sprayer (R & D sprayers) equipped with a single TeeJet nozzle (8002 VS). The sprayer was operated at 35 PSI and calibrated to deliver 300 gpa of finished spray. Treatments were applied once on 13 May. Plots were irrigated immediately following insecticide treatments with approximately 1 inch of water. Population density of CRW was assessed by examining 4 randomly selected 1-ft2 by 4-inch deep areas from each replicate for larval stages. Pre-treatment estimates were made 8-10 May and post-treatment counts 5-7 Jun.