The COTMAN system suggests that insecticide treatments after NAWF=5 plus 350 heat units are no longer protecting bolls that likely contribute to harvestable yield and hence are uneconomical. This paper reports on efforts to test this hypothesis. Mean yields were statistically different in only 3 of 32 cases. The number of applications saved by terminating based on the COTMAN recommendations averaged 1.66 reducing insect control cost by $19.33 /acre