Abstract: | Amounts of spray drifting downwind from a field sprayer applying picloram or paraquat were determined and compared with the damage done to bean and barley plants. Measurements downwind of a stationary spray-boom showed that drift increases rapidly with both wind speed and boom height. It was concluded that it is possible to set a safe distance downwind for the application of a herbicide which affects plants only in the wetted areas but with a sensitive crop and many growth-regulating materials this will be very difficult. |