I am going to give you a report on cottonseed oil as a carrier for pesticides in the Rio Grande Valley. We are going to take a look at a boll weevil study, herbicide studies, and oil formulations. We are going to make a comparison of droplet sizes, deposition, the drift complaint generated by the TDA for the past three years, and the yield of the last two years versus the yield of the past twenty years. We will also compare the number of applications needed for insect control using oil versus water.

Joe Martinez with Mobay Chemical set up a weevil study this past year in the Rio Grande Valley with replicated plots using cottonseed oil as a carrier versus water as a carrier. He used one pint Guthion 2L in both treatments. Joe sprayed all treatments the same at four day intervals with a total of seven applications. Counts were made three days after each application. The following numbers are an accumulation of the percent of punctured squares for the season on all the reps: In the water treatment 17.7% had punctured squares, in the oil treatment 6% had punctured squares. He also ran a live weevil count on the third day after each application. In this count, the water treatment averaged two live weevils per rep and the oil treatment averaged 0.16 live weevil per rep. After the fourth application Joe gave me a call and said he had made a rather good observation and he wanted me to take a look at the plots. We drove out to the plots and from the back end of the pickup we could identify the individual reps of oil treatments by the number of blooms on the cotton. There were many more blooms on the oil treated cotton. Later after the tests had been concluded, Joe told me if he runs the test another year he will use oil to trigger the spray rather than running the four day interval for the water. He thinks had he used longer intervals that the difference between water and oil would have been even greater than what he reported.