The viscosity of vegetable oil-pesticide mixtures is much higher than that of water-pesticide mixtures, especially at low temperatures. Flow rates of soybean oil through regular flat fan nozzles are similar to those of water, while flow rates through flooding nozzles decreased dramatically when soybean oil was sprayed. Soybean oil increased the flow rate through hollow cone nozzles as compared to water with a decreased flow as temperature increased from 25 to 40°C for the TX4 and TX6 nozzles. In field applications grass control decreased as oil was added to water as a carrier, especially at the 50% concentration. There was very little difference in weed control when using either water or soybean oil as the carrier for low-volume application of foliar herbicides. Trends indicate improved grass control and decreased broadleaved weed control when using soybean oil as a carrier as compared to water.