Colorado Potato Beetle Control with Traditional Insecticides, 1991

Superior' potatoes were planted 1 Mar, near Nixonton, NC, on 42 inch centers. Thimet 15 G (3.0 lb [AI]/acre) was applied in furrow at planting. Plots consisted of single rows, 10 ft long, replicated 4 times in a randomized complete block design. Alleys of 5 ft were used between replicates. Treatments were applied with a CO2 pressurized backpack sprayer with a single hollow cone nozzle (18 × ) . Application rate was 80 gal/acre delivered at 50 psi. Applications were made 2 May (all materials) and 9 May (2 rates of Trigard and Thiodan). Counts of insects on 3 hills/plot and visual damage ratings were made 9 and 14 May. Small larvae were assumed to be first and second instars, and large, third and fourth. Potatoes were harvested and yields recorded 10 Jun.