Abstract 'Russet Burbank' potatoes were planted Mar 30 in Ritzville silt loam soil {Mesic Colciorthidic Haploxerolls) with a pH of 6.2 and 1.6% organic matter at Yakima, WA. On Jun 6, the foliar insecticides were applied in 40 gal of spray/acre with a 2-row portable boom CO2 hand sprayer. The plants were 12-14 in. high and each plot was 2-rows wide (5.6 ft) and 25-ft long. Each treatment was replicated 3 times in a randomized complete block design. The number of aphids/20 compound potato leaves per plot was determined at 3, 6, 9, and 14 days after treatment (Jun 9, 12, 15 and 20). Also, the number of dead and live Colorado potato beetle adults and larvae on 3 m2 of soil surface (3 m long × 1 m wide) between the rows of each plot was counted on Jun 7 (24 h after treatment); and the number of adults and larvae on 2 m2 of potato plant area of each plot was on Jul 7 (31 days after treatment). The aphid and Colorado potato beetle data were subjected to analysis of variance with Duncan's MRT. The percent mortality for Colorado potato beetle one day after treatment was calculated for each plot and analyzed.