The application speed is directly proportional to the flow rate of the nozzle. If the flow rate increases by 10%, the application rate increases by 10%. Changes in operating pressure will change the flow rate of the nozzle. In summary, the four factors are wind speed, height of the plume, distance to susceptible vegetation and size of aerosol particles.
Three basic things affect the number of gallons applied per acre. If you run the tractor twice as fast, you will apply half the rate, if nothing else changes. If there are variations in the field, several areas of speed control may be needed. Remember that the time needed to cover the distance traveled will indicate the speed of the sprayer, so the distance and time measured must be exact.
In general, a small change in nozzle flow can be achieved by increasing or decreasing pressure within the nozzle pressure limits. Compare the flow rate of each nozzle you have determined at a given spray pressure with the flow rate listed in the nozzle catalog for that nozzle at the same pressure.