Impact of applying vegetable oils into sweet corn silks on corn earworm damage and sap beetle population at harvest was evaluated in 2006 and 2007. Six vegetable oils used in this experiment were canola, corn, olive, peanut, sesame, and soybean oils. Two commercial plant-based oils (Sun-spray® and Neemix®) and water were used as controls for the experiment. Oil application was performed at two developmental stages (pre- and post-pollination) of the sweet corn plants. At pre-harvest, corn earworm damage ratings and sap beetle populations were recorded and compared. Ramification of this experiment would also be discussed.