Evaluation of Insecticides Against Lepidopterous Pests in Cranberries, 1995

This trial was conducted on a bed of ‘Earlyblacks’ at the Rutgers Blueberry and Cranberry Research Center, Chatsworth, NJ. Treatment plots were arranged in a RCB design with 5 replications. Plots were 4-m by 4-m, separated by buffers of 1-m strips of cranberries within each block and 3-m between blocks. GM larval populations in each plot were augmented on 7 May by placing 4 eggmasses, obtained from USDA-APHJS facility at Otis Air Base in Cape Cod, MA. All GM eggmasses completed hatching by 10 May and larvae were well distributed in each plot at the time of insecticide application. Treatments were applied once on 20 May with a CO2 pressurized Model T backpack sprayer (R & D sprayers) equipped with a single TeeJet nozzle (8002VS). The sprayer was operated at 35 PSI and calibrated to deliver 250 GPA finished spray. Most larvae of SFW and BHFW were third and fourth instar at the time of insecticide application. Larval population was assessed by examining all uprights in 4 randomly selected 1 -ft2 areas per replicate. Pre-treatment estimates were made 15-16 May and post-treatment counts on 31 May. GM larval counts were not taken before the application of insecticides. Larval counts of BHFW and SFW were pooled because of low pest pressure.