Crucifer flea beetle, Phyllotreta cruciferae (Goeze), is an economic pest of seedling canola. Canola is an important crop of North Dakota agriculture and it is becoming expensive to produce due to high input costs of pesticides, seed and fertilizer. Efficacy and agronomic performance of using reduced proportions of insecticide-treated canola seed was compared using commercially available seed treatments at their low and high rates. Four different proportions of treated seed were evaluated: 0%, 33%, 67%, and 100% treated seed. Results from six site years indicate that flea beetle feeding injury to seedling canola is inversely related to proportion of treated seed. The 100, 67, 33, and 0% treated seed treatments had an average injury rating of 3.2, 3.6, 4.0, and 5.0. respectively, across site years. Yield was generally higher for 100% treated seed and decreased proportionally as percentage of treated seed declined regardless of seed treatment. This research indicates that proportion of treated seed at high or low rates of insecticide seed treatment can influence flea beetle control, and agronomic performance of canola.